Psittaciformes Flashcards
What was the effect of a 4.7 mg deslorelin implant in cockatiels?
None of the deslorelin-implanted birds laid eggs within 180 days after implantation, and only 5 of 13 deslorelin-implanted birds laid an egg during the study period (first egg laid between 192 and 230 days after implantation)
Source: Am J Vet Res. 2017;78:745–751. Evaluation of the effects of a 4.7-mg deslorelin acetate implant on egg laying in cockatiels (Nymphicus hollandicus)
GnRH agonists have been used for chronic egg laying and chronic hypersexuality, anecdotally for ovarian cysts and ovarian neoplasia
GnRH mechanism:
Step 1- pituitary gland is stimulated which increased FSH and LH = initial increase sex hormones.
Step 2- continuous stimulation of pituitary → desensitization → to decrease FSH, LH, and sex hormones
Leuprolide acetate- synthetic GnRH agonist
Has a 1-2 week delay in onset of step 2
Deslorelin acetate
Japanese quail: 4.7mg implant last ~70 d, 2 x 4.7 implants lasted ~100 d, 9.4mg implant lasted ~182 d
Pigeons 4.7mg lasts 49 days
Chickens 4.7 mg lasts 180 days; 9.4mg lasts 319 days
Mallards 4.7mg implants lasts 6 weeks
Budgies 4.7mg implants lasts 9 months
Key Points:
4.7 m deslorelin implant prevented egg laying for 180 days in paired cockatiels
Side effects: transient skin erythema at implantation sit
What is the duration of action of butorphanol in parrots?
How can this be increased?
1-3 hours in Hispaniolan amazons.
Mixed with a poloxamer 407 hydrogel, butorphanol can have an extended release leading to 4-8 hours of analgesia.
Source: AJVR 2017 78(6):688–694. Pharmacokinetics of butorphanol tartrate in a longacting poloxamer 407 gel formulation administered to Hispaniolan Amazon parrots (Amazona ventralis)
How does the minimum alveolar concentration of isoflurane in white eyed parakeets differ from other birds?
How is that affected by tramadol?
What is the mechanism of action of tramadol?
Higher (2.5%) than other birds (1-1.5%).
Tramadol did not affect MAC. It also did not affect time to extubation.
Tramadol is a synthetic opioid that enhances release of serotonin & NE and inhibits their reuptake.
Source: JZWM 48(2): 380–387, 2017. EFFECTS OF TRAMADOL ON THE MINIMUM ANESTHETIC CONCENTRATION OF ISOFLURANE IN WHITE-EYED PARAKEETS (PSITTACARA LEUCOPHTHALMUS)
What is a teratoma?
How are they classified histologically?
Where do they occur most often in birds?
- neoplasm that originates in germ cells and is formed by the inclusion of cells or tissues from two or more embryonic layers, endoderm, mesoderm, and ectoderm
- classified histologically - mature vs immature
- mature - well-differentiated tissues, typically benign
- immature - poorly differentiated tissues, may be malignant
- originate mainly from gonadal tissues - in the coelomic cavity
- may originate from ovary, Meckel’s diverticulum, kidneys, or adrenal gland
JZWM 48(2) : 559-562. 2017. COELOMIC TERATOMA IN A BLUE-AND-YELLOW MACAW (ARA ARARAUNA)
What are the defining anatomic features of the family Cacatuidae?
Presence of a gallbladder
Superficial position of left carotid artery
ossified orbiatl ring in the skull
abscense of blue and green plumage
movable feathered crest
Fowler 8 Psittacines
What foot pattern do parrots have?
Zygodactyl
2,3 forward - 1,4 backward
What unique features do lories & lorikeets have to help them feed on nectar & pollen?
What is the main source of protein in the diet?
Erectile dermal papillae on the tongue
Pollen main source of protein
- Muscular tongue has brush tip
- Distal esophagus has fewer mucin glands (no need to lubricate food)
- Proventriculus has compound glands in rows with gland free space to allow expansion (pollen digestion)
- Longer intermediate zone lacks koilin (pollen storage)
- Decreased mass of muscular ventriculus (except rainbow lorikeets with generalized diet)
- Proventricular/pyloric openings lie in median plan, allowing rapid passage of ingesta
- Shorter intestinal tract (except in 1 study), underdeveloped cecae
- Rapid ingesta transit time, forceful expulsion of feces to avoid dirty feathers with very moist droppings
Fowler 8 Ch 21
What psittacines lack a uropygial gland?
Parrots - amazons & anodorhynchus (Hyacinth) - Fowler 8 Ch 21
What unique features of the parrot bill facilitates an increased gape adn shock absorption (for cracking nuts)?
Articulation of the upper mandible in the cranium at the naso-frontal hinge
ZPP Ch 32
What is strange about the appearnce of the gonads of some parrot species on necropsy or surgery?
The are pigments (dark green to black) in cockatoos & some macaws.
ZPP Ch. 32
What are the three psittacine superfamilies?
What groups do they contain?
Strigopoidea
- Nestoridae (kea & kaka)
- Strigopidae (kakapo)
Cacatuiodea
- Cacatuidae - the cockatiels & cockatoos
Psittacoidea
- Psittacidae
- Psittacinae - Greys & Poicephaus
- Arinae - Macaws, Amazons, Caiques, Parakeets
- Psittaculidae
- Platycercinae - ground parrots, broad-tailed parrots
- Lorinae - lories, lorikeets, budgies, fig parrots
- Psittaculinae - pygmy par
What is the scientific name of the Kakapo?
What is unique about this bird anatomically and behaviorally?
Strigops habroptilus; Family Strigopida, Subfamily Srigopina
Critically endangered – New Zealand
- Habitat loss and predation
- Introduced rats and carnivores, esp. stoats (Mustela ermine)
- Survives only on predator-free off-shore islands
- NZ DOC reports 123 birds as of March 2010
Unique and Unusual Features:
- Flightless and nocturnal
- Biggest body mass and most extreme sexual dimorphism of any parrot
- Males 1.6 to 3.6 kg (mean 2.11 kg)
- Females 0.9 to 1.9 kg (mean 1.45 kg)
- Average seasonal wt gain 25%, but can fluctulate by 100% over the year
- Herbivorous
- Unusually large crop
- Markedly reduced keel and pectoral muscle mass
- Simple gut, thin-walled gizzard, no caecum
Behavior and Reproduction
- Lek mating system
- Male constructs a track and bowl system on an elevated site
- Male stands in bowl and emits a series of low-frequency booms
- Heard up to 5km
- Claims territory and attracts females
- Female lays clutch of 2-4 eggs in natural holes or cavities at ground level
- Male takes no part in incubation or rearing of the altricial chicks
- 30 day incubation
Fowler 6
Describe the appropriate husbandry for psittacine enclosures.
Housing (F8)
- Metal enclosures best due to strong beaks
- New galvanized wire should be washed in a vinegar solution and rinsed with water to remove zinc deposits
- Most need warmer temperatures
- Daily access to fresh air and sunlight are recommended for well-being and to promote good bone density and feather quality
- Enrichment and chewing items
What are some of the more commonly encountered issues with psittacine nutrition?
What does the ideal diet look like?
What is unique about the diet of lories and lorikeets?
Feeding (F8)
- Malnutrition is very common
- High fat, low Ca:P ratio, low sodium, zinc, iron, lysine, and vitamin A are common issues in diets
- Formulated pelleted diets provide the best available option w 25% low energy density fruits and vegetables
- Lories and lorikeets should ideally have a liquid diet
Describe a preventative medicine program for psittacine speices including routine testing, quarantine testing, and vaccination strategies.
Preventative Medicine (F8)
- Routine fecal, cbc/chem
- Chlamydia, herpesvirus, bornavirus, polyomavirus, and BFDV testing when entering a flock
- Polyoma vaccination may be considered in birds that are considered for breeding or are exposed to a large collection and to outdoor birds
- WNV causes little disease in most parrots and vaccination may not provide protection
Name three common nutritional diseases in Psittacine Birds.
What are common lesions with these diseases and are their any predisposing factors?
- Nutritional
- Hypovitaminosis A
- Epithelia squamous metaplasia = hyperkeratosis in multiple locations
- Common in seed diets
- Goiter
- 3 mechanisms: iodine (± selenium) deficiency, ingestion of goiterogens (Brassica and Crucuferae plants), and hereditary biosynthetic defects.
- Leads to hypothyroidism
- Thyroid control is different in birds than mammals.
- T4 levels are approx. 10% the concentrations found in mammals
- TRH (hypothalamus) stimulates growth hormone (pituitary, not TSH)
- GH turns T4 to T3. Then T3 stimulates T4.
- Pressure of goiter can produce respiratory clicks
- Hemorrhagic diathesis – bloody intestines as a result of anorexia. Common in small birds. Not the same as hemorrhagic enteritis.
- Hypovitaminosis A
Terio
Describe the filtration of uric acid
- Gout – Uric acid is primary nitrogenous waste compound
- 90% uric acid secreted by proximaly tubules, 10% filtered by glomerulus.
- Any condition leading to sever dehydration, damage to prox tubule, urine outflow obstruction, congenital kidney issues.
Terio
What is the toxic principle of teflon?
What gross findings on necropsy
- Polytetrafluoroethylene (PTFE or Teflon) – inhaled toxic (when overheated)
- Direct damage to type I pneumocytes and capillary endothelial cells
- Many other airborne toxins, self-cleaning ovens
- Looks for congested, red, wet lungs. Pulmonary edema.
- TEM after PTFE toxicity = tracheal mucosal and tertiary bronchiolar epithelium degeneration and ulceration with necrosis of air capillary membranes.
Terio
What is the toxic principle of avocado?
What lesions does it cause in pscittacine birds?
- Avocado – persin is toxic substance. SQ edema and hydropericardium.
- Histopath = myofiber degeneration, inflammation is uncommon.
- Lung congestion. Diagnose = history, lesions, find in GI tract
Terio
What genera of parrots most commonly are affected by atherosclerosis?
What lesions are present on gross and histo?
How is the heart affected?
- Atherosclerosis – SUPER COMMON In middle age and older birds
- Reported most often in three genera: Psittacus, Nymphicus, and Amazona
- Vascular intimal thickening and mural lipid accumulation
- Aorta, brachiocephalic trunks, pectoral and carotid arteries are common sites
- Coronary artery involvement is rare
- Gross = thickened arterial wall with yellow intimal plaques
- Histo = vacuolated smooth muscle and macrophages within intima
- Mural mineralization is less common in birds than mammals.
- Heart = LV dilation, dilation of LA, right heart dilation, and right heart failure.
- Neuro signs possible = cerebral anoxia due to narrowed carotid arteries.
- Turkey: abdominal aorta is muscular and more susceptible to atherosclerosis than the thoracic portion. Lesions in sciatic arteries. Overall have different distribution than other birds, and may have associated aneurismal dilation.
Terio
An older Amazon parrot presents with a history of exercise tolerance and respiratory difficulty.
What is a unique differential for this group of birds.
What changes may be seen on clin path or on gross?
- Chronic Pulmonary Interstitial Fibrosis (CPIF)
- Older Amazona. Presents as exercise intolerance. History of resp disease
- More described in Europe, but seen in N. America too
- Secondary cardiomyopathy - right ventricular hypertrophy or dilation.
- Severe cases may develop increased PCV and erythrocyte size – compensatory for reduced O2 exchange
Terio
Is egg yolk coelomitis associated with what chronic conditions?
Are any bacteria commonly isolated?
Any psittacine species overrepresented?
- Egg Yolk Coelomitis – chronic repro tract disease (neoplasia, salpingitis), rupture, ectopic
- Egg yolk with (E. coli, Staph) or with out bacteria causes severe inflammation
- Common in cockatiels. Present in respiratory distress with fluid distended coelom.
- Retrograde yolk inhalation may occur leading to embolic pneumonia.
Terio
Describe the compositition of xanthomas
What psittacine species are commonly represented?
Is there a dietary component?
What histologic changes are present?
- Xanthomas
- Nonneoplastic, local depositions of yellowish cholesterol-rich material.
- Common in older budgies and cockatiels.
- Diet cause possible – high fat, cholesterol, genetic or trauma
- Dietary improvement with vitamin A has been curative in less advanced cases.
- Histology – Foamy (fat) macrophages, free lipid, cholesterol clefts
Terio
Both Amazon and African grey parrots have some unique dermatologic presentations.
Describe each of them.
- Wing web dermatitis – Prepatagium and axilla of African greys and love birds
- Etiology unknown. Hypersensitivity, self-induced or hormonal feather loss, or excessive moisture may initiate.
- Chronic scarring may lead to contracture
- Amazon foot skin necrosis
- Delayed hypersensitivity suspected
- Syndrome of foot skin erythema and necrosis with automutilation seen primarily the yellow-naped Amazons
Terio
What is the most common neoplasm of the psittacine GI tract? Describe its behavior.
What species are commonly represented?
What anatomic site is the tumor predisposed to?
- Gastric carcinomas and adenocarcinomas
- Common in budgies, gray-cheeked parakeets, lovebirds, cockatiels, conures, and Amazons
- Tumors often at the proventricular–ventricular junction.
- Wall is thick and irregular, inflamed, hemorrhage and necrotic.
- If cells extend to serosa – peritonitis, adhesions
- Mets uncommon, but can occur
Terio
What is the most common neoplasm of the oral cavity and cloaca of New World Psittacines?
Describe the lesions.
What infectious disease is this neoplasm linked to?
- Papillomatosis
- Most common neoplasm of the oral cavity and cloaca in New World psittacines.
- Oral lesions more common in macaws – choana, base of tongue, glottis
- Cauliflower appearance, may be obstructive.
- Cloacal lesions have cobblestone appearance. May prolapse, ulcerate.
- Linked to infection with psittacid herpesvirus (PsHV) genotypes 1, 2, and 3
Terio
Neoplasia in budgerigars is common. What are the two most commonly reported neoplasms? Describe the clinical signs and gross changes on necropsy.
- Testicular tumors – best described in budgies.
- Seminomas and Sertoli cell tumors are the most common
- Seminomas = tumors of immature germ cells and grossly soft, yellow-red, and cause enlargement of the testis.
- Sertoli cell tumors = tumors of the gonadal-stroma. Generally firm, gray-white, nodular neoplasms.
- Some are functional, resulting in feminization
- Change in cere color in budgies and feather changes in a Nyasa lovebird
- Renal tumors
- Young middle aged male budgies
- Unilateral lameness or paresis
- due to compression of ischiatic nerve it passes through the kidney or from tumor growth into and adjacent to the synsacrum and ilium.
- Nephromas, (adeno)carcinomas do not appear to compromise renal function.
- (Adeno)carcinomas are irregular, nodular, occasionally cystic masses that fill most of the coelomic cavity.
- Adenomas rarely cause gross lesions – diagnosed histologically
- Nephroblastomas (embryonal nephromas)
- Typically large unilateral multilobular masses.
- Budgies presents similar adenocarcinoma, but paresis is uncommon.
Terio
What is the etiologic agent of psittacine beak and feather disease?
Describe the lesions associated with PBFD.
Which group of psittacines is more affected?
- Psittacine beak and feather disease virus (PBFDV) = circovirus (PsCV)
- More common Old World psittacines
- Acute fatal disease nestling cockatoos. Chronic disease in older birds.
- Viral proliferation in germinal cells in feather follicles and the rhamphotheca and results in feather and beak deformities.
- Inclusions are intracytoplasmic, basophilic.
- Also causes necrosis and lymphoid depletion of the bursa of Fabricius, thymus and circulating cells = immunosuppression and opportunistic infections.
- Examine the bursa for lesions
Terio
What are the clinical signs associated with psittacine beak and feather disease?
Are there differences in age groups?
Are there species specific presentations?
- Nestlings typically die within 2 weeks.
- Affects all growing feathers. Flight feathers take longer to develop
- Only the flight feathers may be affected in older nestlings.
- Examine the bursa for lesions
- Older birds – signs at first molt
- Dystrophic feathers replace normal ones.
- The feathers have thick sheaths, hemorrhage within shafts, and pinch off at the base.
- Cockatoos – powder feather affected = shiny beak
- Classically present with generalized feather dystrophy, delayed molt, beak elongation, and fracture (white cockatoos)
- Lovebirds and eclectus – 2 presentations.
- Peracute – pneumonia, enteritis, feather deformities, death
- Chronic – feather degeneration, beak deformity
- Possible that the majority of infected lovebirds infected have no signs
- African greys
- Significant immunosuppression. Feather issues are rarely seen.
- Secondary infections, sepsis, pneumonia, enteritis, death
- Severe leukopenia, anemia from infected bone marrow.
How is psittacine beak and feather disease transmitted?
How long is the incubation period?
How is this disease diagnosed?
- Virus shed in the feces, crop secretions, and feather dust.
- Minimum incubation period is 21–25 days, maximum up to several years.
- Diagnose with PCR or histopath
Terio
How did restructuring the social dynamic of a flock of golden conures assist with reduction of feather damaging behaviors?
SUCCESSFUL REDUCTION OF FEATHER-DAMAGING BEHAVIOR BY SOCIAL RESTRUCTURING IN A GROUP OF GOLDEN CONURES (GUARUBA GUAROUBA)
Dislich M, Neumann U, Crosta L.
Journal of Zoo and Wildlife Medicine. 2017 Sep;48(3):859-67.
Background:
FDB is multifactorial in nature and can include stress/boredom/sexual frustration
Can be secondary to inadequate husbandry regarding enrichment and social structure).
Reduce with enriched environment, places to hide, good nutrition/husbandry, not overcrowded.
Key Points:
Flock of golden conures 🡪 FDB began w. secondary feathers bilaterally then extended to covert and tail feathers.
All birds (affected + non-affected) had higher H:L ratio when compared to published RR
Removing the most severely affected birds and restructured group to M:F ratio 1:1 (higher bird density) caused:
Normal H:L ratio
Recovering feathers
5x increase in number of hatched chicked
Normal H:L ratio + either fully recovered or recovering feathers.
Conclusions: Golden conure flock had reduced FDB, increased fecundity, and normal H:L ratio when male to female ratio was decreased to 1:1.
What is the primary avian glococorticoid?
What CBC changes occurred within 1 hr of an expirimental stressor in HAPs?
EFFECT OF ROUTINE HANDLING AND TRANSPORTATION ON BLOOD LEUKOCYTE CONCENTRATIONS AND PLASMA CORTICOSTERONE IN CAPTIVE HISPANIOLAN AMAZON PARROTS (AMAZONA VENTRALIS)
McRee AE, Tully TN Jr, Nevarez JG, Beaufrere H, Ammersbach M, Gaunt SD, Fuller RG, Romero LM.
J Zoo Wildl Med. 2018 Jun;49(2):396-403.
Background:
- Corticosterone (the primary avian glucocorticoid) can increase with stress in just a few minutes in birds
- In birds, heterophilia and lymphopenia (and increased H:L ratio) have been commonly reported in stress.
- Although, extreme stress in chickens can cause heteropenia and basophilia
Key Points:
- Treatment group had a higher mean corticosterone concentration than control by 60%
- Mean corticosterone levels increased in both groups by 20 minutes and then plateaued
- Total white blood cells in the treatment group were higher than the control group by 40 minutes
- Heterophil to lymphocyte (H:L) ratio was higher in the treatment group after 60 minutes
- There was not a significant lymphopenia, though it has been documented in other avian species
Conclusions: Changes to the avian leukogram (increased heterophils and H:L) can occur within 1 hour of a stress, and corticosterone levels can indicate acute stress in psittacines.
What behaviors increased in response to manual restraint in cockatiels?
Establishing Stress Behaviors in Response to Manual Restraint in Cockatiels (Nymphicus hollandicus)
Turpen KK, Welle KR, Trail JL, Patel SD, Allender MC.
Journal of avian medicine and surgery. 2019 Mar;33(1):38-45.
Physical exam → stress response + behavior changes
Increased: Reactionary behaviors, resting, corticosterone
Decreased: Locomotion, feeding, interaction with the environment, displays of aggression
Change in quality but not amount of maintenance behaviors (preening, defecating, etc.)
Conclusions: Cockatiels have changes in behavior and higher corticosterone after physical exam.
What were the effects of fluorescent lighting vs sunlight on Ca, Mg, Vit D, and feather destruction in HAPs?
Effects of Fluorescent Lighting Versus Sunlight Exposure on Calcium, Magnesium, Vitamin D, and Feather Destructive Behavior in Hispaniolan Amazon Parrots (Amazona ventralis)
Jennifer A. West et al.
Journal of Avian Medicine and Surgery 33(3):235–244, 2019Authors
Housing Amazon parrots outdoors had:
Improved serum vitamin D (calcifediol)
Improved feather quality
Both outdoors and indoors could maintain calcium and magnesium
Indoor group could not maintain vitamin D levels
Conclusions: Outdoor housing improved vitamin D status and feather quality of Hispaniolan Amazon parrots.
Describe clinical signs, dx, tx of iron storage disorder in psittacines.
Difference between hemosiderosis and hemochromatosis?
IRON STORAGE DISEASE IN AFRICAN GREY PARROTS (PSITTACUS ERITHACUS) EXPOSED TO A CARNIVOROUS DIET
O’Connor MR, Garner MM.
J Zoo Wildl Med. 2018 Mar;49(1):172-177.
Key Points:
Iron storage disease (ISD) is caused by elevated serum iron that is stored in the liver as hemosiderin
Encountered commonly in frugivorous or nectivorous birds (increased ascorbic acid increases iron absorption)
Clinical signs of ISD: ascites, hepatomegaly, cardiomegaly, dyspnea, abdominal distension, depression, death
Diagnosis: Liver biopsies are the gold standard
Treatment: low-iron diet, increased tannins/phytates, repeated phlebotomy, chelation therapy
Phlebotomy removes circulating iron-storing ferritin bound to transferrin → replenished with iron stores
Hemosiderosis: iron overload without toxic damage
Hemochromatosis: iron overload where organ damage occurs
Conclusions: Exposure to a carnivorous diet likely caused iron storage disease in three African grey parrots.
Describe anesthesia-related mortality rate in birds vs mammals and whether or not risk factors have been identified for bird deaths?
Outcome following inhalation anesthesia in birds at a veterinary referral hospital: 352 cases (2004–2014)
Seamon AB, Hofmeister EH, Divers SJ.
Journal of the American Veterinary Medical Association. 2017 Oct 1;251(7):814-7.
Outcomes of birds anesthetized with inhalants: survived (86%) >>>> euthanized > died in ICU > anesthetic death
No factors were associated with likelihood of survival
Birds are less tolerant of apnea due to limited functional residual lung volume
Conclusions: Anesthesia-related mortality rate in birds is higher than mammals but no clear risk factors.
Describe isoflurane vs alfaxalone 10 mg/kg IM vs manual restraint in budgies - differences in time to onset of recumbency, lactate, resp rate?
Evaluation of the anesthetic and cardiorespiratory effects of intramuscular alfaxalone administration and isoflurane in budgerigars (Melopsittacus undulatus) and comparison with manual restraint
Balko JA, Lindemann DM, Allender MC, Chinnadurai SK.
J Am Vet Med Assoc. 2019 Jun 15;254(12):1427-1435.
Alfaxalone 5 mg/kg vs. 10 mg/kg IM
10 mg/kg IM produced reliable, safe sedation without adverse effects
5 mg/kg IM only produced mild sedation
Some excitability was noted
Isoflurane vs. alfaxalone 10 mg/kg IM vs. manual restraint
Isoflurane produced recumbency (1 min) quicker than alfaxalone (2.5 min)
Lactate was higher in manually restrained birds
Respiratory rate was lower than baseline for all anesthetized birds, and isoflurane more bradypneic than either group
Conclusions: Intramuscular alfaxalone administration produced effective and dose-dependent sedation in healthy budgerigars and provided a viable alternative to isoflurane anesthesia.
What adverse effect was observed with high doses of alfaxalone in budgies (25 mg/kg)?
Sedative, Cardiorespiratory, And Thermoregulatory Effects Of Alfaxalone On Budgerigars (Melopsittacus undulatus)
Romano J, Hasse K, Johnston M.
Journal of Zoo and Wildlife Medicine. 2020 Mar;51(1):96-101.
Both doses of alfaxalone (15 and 20 mg/kg) in budgies caused:
Safe and effective sedation
Decrease in respiratory rate
At 15 mg/kg alfaxalone, budgie had transient decrease in HR right after injection
At 20 mg/kg alfaxalone, budgies lost glottal tone
At 25 mg/kg alfaxalone, budgies had seizures
Conclusions: Alfaxalone at 15 and 20 mg/kg IM in budgies provided good sedation and a decrease in respiratory rate.
Describe differences between low dose alfxalone IM vs high dose alfaxalone IM vs low dose alfaxalone + midazolam in Quakers?
The Use of Alfaxalone in Quaker Parrots (Myiopsitta monachus)
Whitehead MC, Hoppes SM, Musser JM, Perkins JL, Lepiz ML.
Journal of avian medicine and surgery. 2019 Dec;33(4):340-8.
Key Points:
Lower dose alfaxalone (10 mg/kg) had (compared to other groups):
Slower induction
More response to noxious stimuli (compared to high-dose alfaxalone only)
Shorter recovery
Lower respiratory rate
Biggests decline in heart rate
Respiratory rates increased in alfaxalone-midazolam and high dose alfaxalone groups
Hyperexcitation and muscle tremors were seen in all groups but subjectively smoother in alfaxalone-midazolam
50 mg/kg alfaxalone IM caused respiratory arrest
Heart rate changes with alfaxalone:
Increased: swans (IV), bullfrogs, dogs, calves
Decreased: flamingos (IV), Bengalese finance (with midaz SC), iguanas (IM), red-eared sliders (IM), crocodiles (IV), tortoises (IV), terrapins (IV)
Yellow-legged gulls also had excitatory effects after alfaxalone
Conclusions: Alfaxalone at high doses (25 mg/kg) and alfaxalone (10 mg/kg) with midazolam had increased respiratory rate.
What was observed with alfaxalone 15 mg/kg in budgies vs midaz-butorphanol?
Comparison of the Sedative Effects of Alfaxalone and Butorphanol-Midazolam Administered Intramuscularly in Budgerigars (Melopsittacus undulatus)
Escalante GC, Balko JA, Chinnadurai SK.
Journal of avian medicine and surgery. 2018 Dec;32(4):279-85.
Background:
- Amazon parrots have increased respiratory rate and body temperature when handled
- Intranasal midazolam improved body temperature and decreased corticosterone
- Midazolam-butorphanol decreases isoflurane MAC and improve induction quality
- Alfaxalone had shorter induction times than isoflurane in rose flamingos
Key Points:
- Alfaxalone 15 mg/kg in budgies (compared to midazolam-butorphanol 2.5-2.5 mg/kg) had:
– Faster induction and peak effect
– More success in obtaining radiographs
– Shorter recovery
- Bradycardia (n=2)
Both protocols:
- Provided sedation
- No effect on RR or lactic acid
- Did not stop response to noxious stimuli
Conclusions: Alfaxalone has a faster onset of action and shorter duration of effect when compared to non-reversal of midazolam-butorphanol in budgies.
Describe midaz-butorphanol intranasally in budgies vs midazolam alone or saline control - effect on amt of struggling during restraint, sedation, RR?
Assessment of sedation after intranasal administration of midazolam and midazolam-butorphanol in cockatiels (Nymphicus hollandicus)
Doss GA, Fink DM, Mans C.
American journal of veterinary research. 2018 Dec;79(12):1246-52.
Midazolam-butorphanol intranasally in budgies (compared to midazolam alone or saline) had:
Less struggling during restraint
Deeper sedation
Sedation with midazolam or midazolam-butorphanol intranasally in budgies:
Lessened tachypnea during handling
No effect on body temperature or HR (both still increased)
No adverse effects (not even sneezing)
Conclusions: Midazolam or midazolam-butorphanol can reduce tachypnea during handling of cockatiels and midazolam-butorphanol can reduce struggling.
How did fentanyl affect MAC of isoflurane in HAPs? Effects on HR, BP, body temp?
Effects of three fentanyl plasma concentrations on the minimum alveolar concentration of isoflurane in Hispaniolan Amazon parrots (Amazona ventralis)
Hawkins MG, Pascoe PJ, DiMaio Knych HK, Drazenovich TL, Kass PH, Sanchez-Migallon Guzman D.
American journal of veterinary research. 2018 Jun;79(6):600-5.
Fentanyl reduces isoflurane MAC in red-tailed hawks and chickens
In this study, fentanyl in Hispaniolan Amazons:
Decreased heart rate and blood pressure
Increased body temperature
Reduced isoflurane MAC
Conclusions: Fentanyl IV decreases isoflurane MAC in Hispaniolan Amazons but also decreases heart rate and blood pressure.
Describe differences between half life of fentanyl in RTHA vs HAPs.
Clearance of fentanyl in HAPs vs other avian spp?
Pharmacokinetics of fentanyl after intravenous administration in isoflurane-anesthetized red-tailed hawks (Buteo jamaicensis) and Hispaniolan Amazon parrots (Amazona ventralis).
Pascoe PJ, Pypendop BH, Pavez Phillips JC, DiMaio Knych HK, Sanchez-Migallon Guzman D, Hawkins MG.
Am J Vet Res. 2018 Jun;79(6):606-613.
Background:
Fentanyl is a synthetic mu opioid agonist with a short time to action and short duration of action when given IV
Reported to decrease MAC in red-tailed hawks and Hispaniolan Amazon parrots (Hawkins 2018)
Key Points:
There were large differences between the half life in RTH (90 min) and Amazons (51 minutes)
Fentanyl was cleared more rapidly in the Amazons than in any avian species
Conclusions: Interspecies differences exist among birds, so PK extrapolation should be performed with caution.
What is MAC?
What is the mechanism of tramadol?
What is unusual about the MAC of iso for white-eyed parakeets?
Did tramadol influence MAC in WEPs?
Adverse effects observed?
EFFECTS OF TRAMADOL ON THE MINIMUM ANESTHETIC CONCENTRATION OF ISOFLURANE IN WHITE-EYED PARAKEETS (PSITTACARA LEUCOPHTHALMUS)
Escobar A, da Rocha RW, Midon M, de Almeida RM, Filho DZ, Werther K.
J Zoo Wildl Med. 2017 Jun;48(2):380-387
Minimum anesthetic concentration (MAC) of an inhalant anesthetic is the dose that prevents movements in 50% of individuals exposed to a noxious stimulus
Tramadol is a synthetic opioid that enhances the release of serotonin and norepinephrine and inhibits their reuptake
In Hispaniolan Amazon, antinociceptive effects of tramadol last for up to 6hs PO and up to 4hrs IV
10 wild-caught white-eyed parakeets
Determined isoflurane MAC → 2.45%
Much greater than all other avian MACs
Determined isoflurane MAC 15 min and 30 min after 10mg/kg tramadol IM → 2.49%
Not statistically different from isoflurane alone
No significant differences in HR, RR, and anesthetic recovery time with tramadol
Cloacal temperatures higher at 15 min after tramadol
One bird treated with tramadol regurgitated 4 minutes after extubation
One bird treated with tramadol developed second-degree atrioventricular block
Opioid-induced arrhythmias in birds under inhalant anesthesia described in guineafowl and chickens
Recommended to monitor ECG in anesthetized birds
Tramadol may still have analgesic effects even if no significant change in MAC
Conclusion: Tramadol did not affect MAC in white-eyed parakeets.
What sedative effect was achieved with IN midazolam in blue front amazon and orange winged amazon parrots?
Were adverse effects observed?
How was accuracy and safety of administration improved?
Sedative Effects of Intranasal Midazolam Administration in Wild Caught Blue-fronted Amazon (Amazona aestiva) and Orange-winged Amazon (Amazona amazonica) Parrots.
Schaffer DPH, de Araújo NLLC, Raposo ACS, Filho EFM, Vieira JVR, Oriá AP.
J Avian Med Surg. 2017 Sep;31(3):213-218.
Background:
Intranasal administration is good because there is no pain associated with injection
Midazolam is a hydrosoluble benzodiazepine with anxiolytic and muscle-relaxant properties
Reported adverse effects of intranasal midazolam in birds include persistent sneezing, upper airway noise, trembling, myoclonic seizures, and muscle tremors.
Key Points:
Light to moderate sedative effects were produced with no difference between the sedation scores of the 2 species
Use of a catheter improved accuracy and safety of administration
Similar length of sedation to other psittacines at the same dose (about 15-40 minutes)
No adverse effects except two birds sneezed
Conclusions: Intranasal midazolam at 2 mg/kg was an effective light-to-moderate sedative for wild-caught blue-fronted and orange-winged Amazons.
How did midazolam or midazolam-butorphanol sedation affect transit time, ventricular contraction frequency, and esophageal bolus frequency in cockatiels?
Effects of Midazolam and Midazolam-Butorphanol on Gastrointestinal Transit Time and Motility in Cockatiels (Nymphicus hollandicus)
Martel A, Mans C, Doss GA, Williams JM.
Journal of avian medicine and surgery. 2018 Dec;32(4):286-93.
Midazolam or midazolam-butorphanol sedation in cockatiels:
Increased overall transit time
Reduced ventricular contraction frequency
Reduced esophageal bolus frequency (midazolam-butorphanol only)
Effects were more pronounced with midazolam-butorphanol than midazolam alone
Conclusions: Midazolam and midazolam-butorphanol can slow GI transit time in cockatiels.
Describe utility of 407 paloxamer gel for extension of butorphanol efficacy in HAPs vs OWAPs.
Laniesse, D., Sanchez-Migallon Guzman, D., Smith, D. A., Douglas, J. M., Mosley, C., Beaufrère, H., & Paul-Murphy, J. (2020). Evaluation of the thermal antinociceptive effects of subcutaneous administration of butorphanol tartrate or butorphanol tartrate in a sustained-release poloxamer 407 gel formulation to orange-winged Amazon parrots (Amazona amazonica). American journal of veterinary research, 81(7), 543-550.
Key Points:
- Thermal or electric withdrawal used as antinociception model in multiple avian species
- Butorphanol – k opioid receptor – great analgesic but lasts 2-3 hours
- To extend use it was added to P407 base and worked well in Hispaniolan amazons
- The control butorphanol worked great (for >30 but <90 minutes) but the P407 did not
Take-Home: Species differences exist. Butorphanol in P407 appears to work in Hispaniolan but not Orange-Winged Amazon parrots
Describe recoveries of black-cheeked lovebirds sedated with alfaxalone for non-invasive procedures.
Greunz, E. M., Limón, D., & Bertelsen, M. F. (2021). Alfaxalone sedation in black-cheeked lovebirds (Agapornis nigrigenis) for non-invasive procedures. Journal of Avian Medicine and Surgery, 35(2), 161-166.
- 12.6 mg/kg SC alfaxalone provided nearly 1 hour of excellent sedation for noninvasive procedures in black-cheeked lovebirds
- loss of reaction to noxious stimulation was not achieved
- SC injection was effective and reliable
- majority of inductions and recoveries were rough, characterized by uncoordinated movement
- SpO2 values were consistently high and RR acceptable
Label the following bones
Beaufrère, H., Laniesse, D., Kabakchiev, C., Axelson, R., & Zur Linden, A. (2019). Multiple fractures and luxations of palatofacial bones in a hawk-headed parrot (Deroptyus accipitrinus). Journal of the American Veterinary Medical Association, 254(2), 251-256.
Chalmydia psittaci infection in birds - transmission, clinical signs, case definitions, diagnostic testing.
Compendium of Measures to Control Chlamydia psittaci Infection Among Humans (Psittacosis) and Pet Birds (Avian Chlamydiosis), 2017
Gary Balsamo, Angela M. Maxted, Joanne W. Midla, Julia M. Murphy, Ron Wohrle, et. al.
Journal of Avian Medicine and Surgery 31(3):262–282, 2017
Infection in Birds (Avian Chlamydiosis)
Transmission:
Excreted in ocular and nasal discharges or feces.
Length of time shedding varies by sps of bird and chlamydia strain
In organic debris, organism can remain infective for a month
Can have subclinical carriers and shedders.
Shedding can be exacerbated by stress, reproduction, shipping, crowding, illness
Clinical Signs:
3d to weeks incubation
Subtle resp illness OR mild conjunctivitis OR Death
Usually nonspecific signs: lethargy, anorexia, conjunctivitis, ocular or nasal discharge, URI, diarrhea, liver disease (abN colored feces)
Case definitions: needs at least one of the following
Isolation of C psittaci from clinical specimen
ID chlamydia DNA (PCR). IHC is NOT diagnostic
4x or greater change in serologic titer in 2 specimens from same bird at least 2 weeks apart assayed simultaneously at the same lab
ID of intracellular bacteria stained with Gimenez or Macchiavello stain + detection of C psittaci DINA in same tissue
A suspected case= CS + one of the following
Chlamydia (nonspecific) PCR on conjunctival, choanal, cloacal swabs OR blood OR feces
Chlamydia antigen IFA on feces, cloacal swab, resp secretion (IFA cross reacts with non chlamydia- FYI)
Epidemiological linked to a known/confirmed case
Diagnosis
Combination of culture, PCR-based detection, and antibody detection is recommended.
No epidemiological evidence of increased risk of disease to young, elderly, or immunocompromised patients.
CS birds: cloudy air sacs, enlargement of liver or spleen.
Post-mortem spleen or liver are preferred for culture
Live birds: combo of conjunctival-choanal-cloacal swab culture or liver bx and culture
If using feces, need to collect serial fecal specimens for 3-5 consecutive days and pool into single sample for culture
Ab tests: positive serologic test just indicates exposure at some point, but not that the animal is still infectious.
False negative in acute infection
4 fold or greater increase in serologic titer OR a combination of positive titer and antigen ID is needed
Elementary body agglutination (elementary body is the infectious form of C psittaci). Favors detection of IgM which reach high levels in acute stage of infection. Titers 10 or higher are positive. But increased titers can persist after successful treatment
Indirect fluorescent ab test: IgG ab. Sensitivity and specificity not great, can get cross reaction
Complement fixation: more sensitive than agglutination, but false negatives esp form parakeets, African gray parrots and lovebirds.
High titers persist after treatment
Modified direct more sensitive than direct
Tests for antigen: do not require live organisms. Can get false positives. And cross reaction can occur. False negatives if shedding is intermittent.
ELISA not recommended
Fluorescent ab test: used to detect organism on impression smears . lots of cross reactivity. Not recommended.
Test for DNA -PCR is sensitive and specific to detection of target DNA sequences. , but results differ between labs because no standardized primers and lab techniques. Not all PCR can tell apart different chlamydia
In-situ hybridization preferred method for documenting chlamydial organisms with in fixed tissue.
Additional testing
Genotyping: Genotype A predominates in psittacines. Genotype B predominates in columbiformes.
Screening protocols using diagnostic tests:
Use PCR that can distinguish C psittaci from other related Chlamydia.
At least test cockatiels, lovebirds, larger psittacines tested on conj-choana-cloaca swab during quarantine.
Conjunctiva is most sensitive for detecting chronically infected cockatiels with minimal CS
In budgies ONLY- house 20-25 birds together for 12-24 hours and then collect composite swab from the floor, perches, rims of water and food bowls, and feces, pool it and test. Not shown to be effective in other sps.
Treatment of chlamydia psittaci in birds and recommendations for controlling infection among humans and birds?
Compendium of Measures to Control Chlamydia psittaci Infection Among Humans (Psittacosis) and Pet Birds (Avian Chlamydiosis), 2017
Gary Balsamo, Angela M. Maxted, Joanne W. Midla, Julia M. Murphy, Ron Wohrle, et. al.
Journal of Avian Medicine and Surgery 31(3):262–282, 2017
Treatment
Historically, treatment periods are 45 days. More recent info suggests 21-30 days of treatment could be effective.
Remove extra dietary calcium from environment as ca can inhibit absorption of tetracyclines
Doxycycline:
Drug of choice for birds- eliminated slower and better absorption than other tetracyclines so lower dose and less freq administration needed.
Signs of toxicosis: yellow or green urates, lethargy, elevated LE
Budgies and cockatiels have a medicated feed that is approved
Medicated water- PK studies for some sps. 400-600mg/L water in larger psittacines.
Do NOT use medicated water for budgies- does not maintain therapeutic concentrations
PO or injectable works too.
Only one form of doxy is acceptable for IM injections, all other forms may cause severe tissue reactions if given IM
Alternative drugs:
Azithromycin: COckatiels treated for 21 days had resolution
Oxytetracycline injectable, long acting SQ given every 3 days in larger psittacines.
Causes irritation at injection site.
Chlortetracycline medicated feed: available as mash, pellets, extruded (Doxycycline is better)
It is NOT recommended to treat water with Chlortetracycline, Oxytet or other tetracycles
Part 3: Recommendations for controlling infection among humans and birds
Educate persons at risk: respiratory or influenza-like symptoms should seek prompt medical attention and let health care provider know about bird contact.
Reduce risk of transmission to humans: PPE: coveralls, gloves, eyewear, footwear, N95 mask. NX of suspect cases in biosafety cabinet
- maintain accurate records of bird related transactions for at least 1 year
Avoid purchase or selling birds with resp illness could be associated with chlamydia
Avoid mixing birds from multiple sources
Quarantine new birds
Test birds for chlamydia status before acquiring birds
Screen birds with frequent public contact
Practice preventative husbandry- non-dusty bedding, clean things regularly, disinfect (susceptible to detergents, heat. Resistant to alkali and acid)- best to use quaternary ammonium compounds or oxidizing agents.
Care for sick birds last
Did captive or wild birds have a higher prevalence of Chlamydia psittaci in Australia? Males vs females?
SURVEILLANCE FOR CHLAMYDIA SPP. WITH MULTILOCUS SEQUENCE TYPING ANALYSIS IN WILD AND CAPTIVE BIRDS IN VICTORIA, AUSTRALIA
Amery-Gale J, Legione AR, Marenda MS, Owens J, Eden PA, Konsak-Ilievski BM, Whiteley PL, Dobson EC, Browne EA, Slocombe RF, Devlin JM.
Journal of wildlife diseases. 2020 Jan;56(1):16-26.
C. psittaci obligate intracellular bacterial pathogen
Notifiable disease
Primary infects birds (highest prevalence in psittacines and columbiformes)
Signs: respiratory, hepatitis, splenitis, wasting, death or subclinical carrier
Treatment with tetracyclines
Key Points:
Higher prevalence of Chlamydia psittaci in captive birds (8%) vs. wild (0.7%)
Males >> females
Many positive birds in this study also had beak and feather disease virus (suppresses immune system)
Conclusions: Male captive birds were the most commonly affected by Chlamydia psittaci in opportunistic screening in Australia.
What is the gold standard for diagnosis of mycobacteriosis in psittacines?
MYCOBACTERIOSIS IN CAPTIVE PSITTACINES: A BRIEF REVIEW AND CASE SERIES IN COMMON COMPANION SPECIES (ECLECTUS RORATUS, AMAZONA ORATRIX, AND PIONITES MELANOCEPHALA)
McRee AE, Higbie CT, Nevarez JG, Rademacher NT, Tully TN Jr.
J Zoo Wildl Med. 2017 Sep;48(3):851-858.
Mycobacteriosis has been identified in a wide variety of captive and free-ranging avian populations
Historically Mycobacterium avium subsp. Avium and M. genavense
M. avium subsp. Paratuberculosis has not been identified in avian cases of Mycobacteriosis
Transmission is likely fecal-oral, though inhalation of aerosolized particles is possible
Mycobacteria can persist in the environment for years.
Infectious vacilli is ingested, colonizes liver and small intestines
Dissemination can cause disease of bone marrow, lungs, air sacs, spleen, gonads, kidneys, and pancreas
Affected organs are enlarged with diffuse macrophage accumulation +/- granulomas
Clinical signs: weight loss, unkempt feathers, polyuria, polyphagia, diarrhea, and coelomic distension
Marked leukocytosis with heterophilia and monocytosis, anemia
Enlarged cardiohepatic silhouette, thickened intestinal loops, increased opacity of endosteal bone of humerus, tibia, ulna, and femur
Acid-fast bacteria in feces in later stages
Diagnosis is confirmed by culture, isolation, and genetic identification, though this takes months
Gold standard for mycobacteriosis = biopsy of affected tissue with consistent histopathology, culture, and nested PCR
Most common mycobacterial isolate in humans is M. avium susp. Hominissuis, though M. genavense infection is possible
Environment is more likely to be a source of infection rather than birds
Euthanasia is recommended due to zoonotic threat, poor prognosis
Treatment is difficult, and treatment with combination therapy for >12 months is recommended
M. tuberculosis from human to macaw has been reported
Have your caregivers screened
Conclusion: Mycobacterium spp. still persists as a relevant disease and should be kept as a differential for any insidious, nonspecific, disease process in psittacines.
Most common pathologic findings in a retrospective of mycobacterium genavense? What fungal coinfection was common?
Retrospective Evaluation of Clinical Signs and Gross Pathologic Findings in Birds Infected With Mycobacterium genavense.
Schmitz A, Rinder M, Thiel S, Peschel A, Moser K, Reese S, Korbel R.
J Avian Med Surg. 2018 Sep;32(3):194-204.
Mycobacterium avium subspecies avium has been thought to be the primary pathogen of mycobacteriosis in psittacines
Mycobacterium genavense has been shown as the causative agent in passerine and psittacine cases
Clinical signs of mycobacteriosis are nonspecific
Necropsy may show enlarged liver, granulomatous tubercules, or no lesions at all
M genavense is highly pathogenic for immunocompromised people.
Key Points:
Wide range of clinical findings (feather disorders, GI signs, falling off the perch, no signs, seizures, ocular disease)
Ocular signs typically involved the adnexa with periocular swelling
Most common pathologic findings were enlarged liver, dilated intestines, reddish lungs
White nodules found in 21% of birds
Coinfections were very common with fungal infections (47%, e.g. Macrorhabdus ornithogaster) more common than bacterial infections (14%)
Psittacine birds were more likely to have a poor body condition, hepatomegaly, and nodules compared to passerines
51% of birds had mild to absent pathologic findings
Cases found in a wide range of avian orders
Conclusions: Mycobacterium genavense presents with a wide variety of clinical syndromes and orders, and is associated with coinfections in birds.
Ddx for granulomatous conjunctivitis in cockatiels?
Retrospective Review of Mycobacterial Conjunctivitis in Cockatiels (Nymphicus hollandicus)
Stephanie K. Lamb, Drury Reavill, Rebecca Wolking, Bob Dahlhausen
J. of Avian Medicine and Surgery, 34(3):250-259 (2020)
Mycobacteria spp.: slow growing, aerobic, acid-fast, resistant to extremes within environment
Most common species of psittacine with mycobacteriosis:
Budgies, brotogeris parakeets, Amazons, pionus (common reports)
Cockatiels, Amazons (in a postmortem study)
Most common Mycobacteria spp. in psittacines = M. genavense
Most common locations = intestines, liver, spleen, bone marrow
Key Points:
Cockatiels had granulomatous inflammation of conjunctiva with acid-fast positive bacteria
Confirmed mycobacteriosis with PCR of biopsy (most were M. genavense)
Variable survival
Conclusions: Mycobacterium genavense can cause granulomatous conjunctivitis in cockatiels.
Most comon isolate for superficial cutaneous ulcerative disease in a 2017 review? Most common location? Most common spp affected?
Superficial Chronic Ulcerative Dermatitis (SCUD) in Psittacine Birds: Review of 11 Cases (2008-2016)
Abou-Zahr T, Carrasco DC, Shimizu N, Forbes NA, Dutton TA, Froehlich F, De Bellis F.
Journal of avian medicine and surgery. 2018 Mar;32(1):25-33.
Background:
Superficial chronic ulcerative dermatitis (SCUD) = described bacterial dermatitis lesions secondary to self-mutilation
Common isolates = Staphylococcus aureus, Enterobacter cloacae
Common species = Lovebirds
Key Points:
Most common species for SCUD in this study = African greys
Common features of birds with SCUD:
Hand-reared, indoors
Imprinted on owners
Sexually mature and expressing sexual behaviors towards owners
No avian companions
Feather-damaging behavior
Most common isolates for SCUD in this study = Enterobacter cloacae (> E. coli, S. aureus)
Most common SCUD location = axilla
No age or sex predisposition
This study had 100% treatment success with antibiotics based on culture results.
Conclusions: Superficial cutaneous ulcerative disease was common in African parrots and axillae caused by Enterobacter cloacae.
Pathology of avian coxiellosis? Dx?
Antemortem Diagnosis of Coxiellosis in a Blue and Gold Macaw (Ara ararauna)
Flanders AJ, Rosenberg JF, Bercier M, Leissinger MK, Black LJ, Giglio RF, Craft SLM, Zoll WM, Childress AL, Wellehan JFX.
J Avian Med Surg. 2017 Dec;31(4):364-372.
Avian coxiellosis is an emerging infectious disease with significant morbidity and mortality among captive birds
Reported in 9 species of birds (8 psittacines, 1 toucan)
Clinical Signs: lethargy, weakness, cardiac/neurologic abnormalities
Pathology: Splenomegaly and hepatomegaly
Histo: Coxiella-like bacteria within macrophages of spleen, liver, bone marrow, kidneys, and adrenals
Granulomatous encephalitis and myocarditis in lorikeets and eclectus parrots
Diagnosis: FNA of organs of concern for cytology, culture, and PCR
Unknown zoonotic potential
Coxiella spp. are obligate intracellular, gram-negative bacteria
Coxiella burnetii causes Q fever, an important zoonotic disease
Transmitted via direct contact or aerosol transmission from infected ruminants, ticks, or rodents
Contact with ruminant placental fluids increase risk for transmission
Not pathogenic in birds
Coxiella-like endosymbionts have been described in >40 species of ticks
Unknown if avian coxiellosis is transmitted via ticks
Conclusion: Avian coxiellosis is an emerging disease of concern in captive avian species, causing hepatosplenomegaly and non-specific clinical signs. Antemortem diagnosis is possible through PCR of FNA of affected organs.
Is cryptococcus gattii a primary or opportunistic pathogen in birds? What about cryptococcus neoformans?
A Disseminated Cryptococcus gattii VGIIa Infection in a Citron-Crested Cockatoo (Cacatua sulphurea citrinocristata) in Québec, Canada
Maccolini ÉO, Dufresne PJ, Aschenbroich SA, McHale B, Fairbrother JH, Bédard C, Hébert JA.
J Avian Med Surg. 2017 Jun;31(2):142-151.
Cryptococcus species are basidiomycetous fungi with C. gattii and C. neoformans as most common pathogens
C. neoformans = opportunistic pathogen; C. gattii = primary pathogen
Recent increase in C. gattii cases in North America
Inhalation is most common route of infection
Strain isolated in this case is most common isolate of ongoing outbreak in British Columbia and PNW
In Australia, C. gattii infects immunocompetent birds as a primary pathogen causing URI and upper beak lesions
C. gattii with cutaneous and pneumatic bone lesions is increasingly reported outside of Australia
C. neoformans infects immunocompromised birds with neurologic and lower respiratory signs
More common than C. gatti in North America and Europe
C. gattii should be a differential for upper respiratory infection and beak lesions in birds
Conclusions: Case of disseminated Cryptococcus gattii infection in an immunocompetent bird in a nonendemic region
What clinical sign is a hallmark of crytococcus infection?
Multicentric Cryptococcosis in a Congo African Grey Parrot (Psittacus erithacus erithacus).
Schunk RSK, Sitinas NE, Quesenberry KE, Grodio JL.
J Avian Med Surg. 2017 Dec;31(4):373-381.
Key Points:
C. neoformans most common species of Cryptococcus in birds; affects immunocompromised
C. gatti associated with warmer climates and eucalyptus trees; affects immunocompetent
Clinical signs: respiratory disease that progresses to gastrointestinal system and CNS.
Thick gelatinous exudate is a hallmark of Cryptococcus infection.
Infection is most commonly acquired from the environment, not infected animals
Debulking gross lesions is recommended (e.g. eye and coelomic mass in this case); prognosis is always guarded.
Conclusions: Cryptococcosis became fatally disseminated despite treatments in a Congo African grey parrot.
Describe the lifecycle of sarcocystis spp - definitive host and intermediate hosts? Most common sarcocystis spp in psittacines? What was a risk factor for death in one case series?
Sarcocystosis In A Captive Flock Of Thick-billed Parrots (Rhynchopsitta Pachyrhyncha) From 2005 To 2016: Morbidity, Mortality, Diagnostics, And Management Strategies
Anne E. Rivas, Kenneth Conley, Tracie A. Seimon, Charlotte Hollinger, Heather Knych, Robert P. Moore, and Jean A. Pare
Journal of Zoo and Wildlife Medicine 52(1): 206–216, 2021
Background:
- Sarcocystis spp.: intracellular coccidia protozoa
- Definitive hosts = carnivores, omnivores
– Site of sexual reproduction
– Signs: Mild enteritis, diarrhea, weight loss
- Intermediate hosts = herbivorous or prey species
– Site of asexular reproduction
– Signs: sarcocysts (containing brady/merozooites) in muscle, brain → severe morbidity, mortality
- Spread by paratenic hosts (e.g. arthrpods)
- Sarcocystis falcatula is the common species in psittacines
– Definitive host = Virginia opossum
Key Points:
- Primary cause of mortality in young adult thick-billed parrots at Queens zoo
- Clin path: elevated CK (sometimes)
- Histo: interstitial pneumonia, skeletal muscle myositis, myocardial myositis, encephalitis
- Treated birds had tubular necrosis, visceral gout, aspergillosis
- Chronic cases had abnormal posture, fluffed feathers, difficulty flying
- Diagnosis via PCR was more sensitive earlier in disease
- Treatment that resolved clinical signs = ponazuril + TMS + pyrimethamine x 6 months
- Did not clear infection
- Risk factor for death: dyspnea
- Primarily diagnosed in young adult birds.
Effective prevention measures:
- Food stations that exclude arthropod/rodent hosts seemed to help
- Daily prophylactic diclazuril also seemed helpful
Conclusions: Disseminated avian sarcocystosis (usually caused by S. falcatula in psittacines) is difficult to prevent, diagnose, and treat, with potential for significant morbidity and mortality.
What are organophosphates?
HINDLIMB PARALYSIS SYNDROME IN WILD CARNABY’S COCKATOOS (CALYPTORHYNCHUS LATIROSTRIS): A NEW THREAT FOR AN ENDANGERED SPECIES
Anna Le Souëf, Simone Vitali, Rick Dawson, Rebecca Vaughan-Higgins, Kristin Warren
J Wildl Dis. 2020 Jul;56(3):609-619.
Background:
An increasing number of wild Carnaby’s cockatoos were presented to the Perth Zoo with hindlimb paresis/paralysis
Organophosphates (OP) = anti-cholinesterase (anti-ChE) toxins that hydrolyze and inhibit acetylcholine
Acute clinical signs: fatal respiratory or cardiac arrest
Absorption via oral, inhalational, or dermal routes
OPs can be stored in fat and mobilized with physical exertion (e.g. migration)
OPs are readily metabolized are rarely found on diagnostics
OP-induced delayed neuropathy = peripheral neuropathy 2-3 wks post-OP exposure in humans, chickens, and a white-fronted Amazon
Key Points:
Carnaby’s cockatoos with hindlimb paralysis syndrome were unable to stand +/- foot clenching, hindlimb paresis/paralysis
Normal neurologic status in wings and head with an intact appetite
Varying body condition
Some had keel ulceration and eschar formation from prolonged sternal recumbency
Most commonly presented in the summer and fall
No sex or age predilection
No other local avian species known to be affected
Few ticks but none known to cause paralysis
Elevated AST +/- elevated CK and heterophils +/- hypoproteinemia
No significant toxins detected (no OPs, only n=1 with nicatinoids)
Consistent with hypothesize of delayed-onset polyneuropathy from OP exposure
No significant depression of brain and plasma AChE activity consistent with delayed polyneuropathy syndrome
Fair survival rate (21/33) with supportive care (fluids, antibiotics, meloxicam)
Average recovery = 8 days
No need for atropine because the OPs are already metabolized
Hypothesize that OP exposure from agriculture during inland breeding then developed signs after migration to coastal Perth
Conclusion: Hindlimb paralysis syndrome in Carnaby’s cockatoos is hypothesized to be from an organophosphate-induced delayed-onset neuropathy that can resolve with supportive care.
What are the three components of the cloaca? Most common species with cloacal disease? Risk factors for cloacal disease?
Cloacal Diseases in Companion Parrots: A Retrospective Study of 43 Cases (2012–2018)
Kristin S. Gill, Peter J. Helmer
J. of Avian Medicine and Surgery, 34(4):364-370 (2020).
Background:
Cloacal components:
Coprodeum: rectum
Urodeum: ureters, paired ductus deferens or left oviduct
Proctodeum: connects coprodeum/urodeum to environment
Bursa of Fabricius: B cell maturation within proctodeum
2 syndromes of cloacal prolapse
Excess hormone stimulation + hypersexual behavior
Progressive idiopathic coprodeal prolapse + straining
Usually cockatoos (umbrellas, Moluccans); also Amazons + B/G macaws
Male, single-parrot household, pair bonded to a human, prolonged weaning period
Key Points:
Most common species with cloacal disease = Umbrella cockatoos
Risk factors for cloacal disease:
Inappropriate sexual behaviors (50% of birds)
Umbrella cockatoos (most common species)
Female
Cloacal or coelomic mass
Abnormal egg laying
Most common organ prolapse = cloacal wall
In raptors, colon is more often prolapsed
No factors for survival identified
Conclusions: Most common cloacal disease scenario was female cockatoos with inappropriate sexual behavior prolapsing a cloacal wall.
Clinical signs of Horner Syndrome in birds?
What topical treatment can confirm the diagnosis?
Horner Syndrome With Ipsilateral Wing Paresis in a Wild, Juvenile Yellow-Tailed Black Cockatoo (Calyptorhynchus funereus)
McLelland JM, McLelland DJ, Massy-Westropp N, Wigmore B, Loftus WK, Read RA.
Journal of Avian Medicine and Surgery. 2020 Jul;34(2):186-91.
Horner’s syndrome in birds has unilateral signs:
Ptosis (eyelid drooping)
Erect feathers and neck (only on the affected side)
+/- Miosis (small pupil)
Topical phenylephrine → transient resolution within 30 minutes
Confirms diagnosis of Horner’s syndrome
Conclusions: Use topical phenylephrine to diagnose Horner’s syndrome in birds.
Horner Syndrome in wild, Australian birds - Age predilection? Other risk factors? Clinical signs?
A Retrospective Study of Horner Syndrome in Australian Wild Birds, 2010-2016.
Hill AG.
Journal of avian medicine and surgery. 2018 Jun;32(2):115-21.
Horner’s = oculosympathetic paresis results from interruption of nerves
Sympathetic n. originates at the hypothalamus → thoracolumbar spinal cord → cranial cervical ganglion → innervate the eye, vasculature, and feather follicles of head and neck.
Signs in birds: unilateral ptosis, erection of facial feathers +/- miosis
No anhidrosis (seen in mammals)
Key Points:
Horner’s syndrome in wild, Australian birds was more common in:
Adults
Trauma
Concurrent neurologic deficits
Poor prognosis (release rate of 32%)
Signs can persist beyond resolution of soft tissue trauma
Improved resolution with meloxicam
All cases unilateral
No seasonality or temporal pattern with admission for Horner’s
Conclusions: Horner’s in avian species is most likely caused by trauma and presents with unilateral raised feathers and ptosis.
Common pathologic findings in birds with heat stress? Findings only observed in doves?
Organ Histopathology and Hematological Changes Associated With Heat Exposure in Australian Desert Birds
Shangzhe Xie, Lucy Woolford, Todd J. McWhorter
J. of Avian Medicine and Surgery, 34(1):41-51 (2020).
Key Points:
Congestion and lymphoid aggregates in liver, lungs, kidneys, and/or intestine were common in all groups
Primary organ affected differed by species
Lung congestion most common overall
Myocardiocyte vacuolation and airway hemorrhage were only seen in doves
Clinicopathologic changes varied by species and heat:
Budgies: increased heterophils and decreased PCV
Doves @ 35 C: decreased eosinophils
Conclusions: Mild heat exposure can induce subclinical heat stress in birds.
Most common spp for SCC, concurrent conditions, most common locations? Treatment?
Clinical features, treatment, and outcomes of cutaneous and oral squamous cell carcinoma in avian species
Zehnder AM, Swift LA, Sundaram A, Speer BL, Olsen GP, Hawkins MG, Paul-Murphy J.
Journal of the American Veterinary Medical Association. 2018 Feb 1;252(3):309-15.
Background:
- Squamous cell carcinoma (SCC) is often locally invasive
- Common locations: skin, mouth, upper GI, , uropygial gland
- Common species: cockatiels, Amazons, budgies
Key Points:
- Most common species for SCC in this study: cockatiels > Amazons > conures
- Common concurrent conditions: hypovitaminosis A > bacterial infection > FDB
- Most common SCC locations: skin > mouth > uropygial gland
- Cockatiels = skin
- Amazons = mouth
- Conures = mouth/beak
- Complete remission most common with complete excision (vs. other nonsurgical treatments)
Conclusions: Squamous cell carcinoma can be cured with complete surgical excision in psittacines.
Which side of the cloaca is the rectal opening in psittacines (differs from chickens, pigeons, birds of prey)?
List surgical procedures used to manage cloacal prolapse.
Benefits of asymmetrical cloacoplasty?
Asymmetrical Cloacoplasty for the Treatment of Chronic Cloacal Prolapse in Psittaciformes: A Case Series.
Zaheer O, Beaufrère H, Jajou S, Gardhouse S.
Journal of Avian Medicine and Surgery. 2020 Jul;34(2):172-80.
Idiopathic cloacal prolapse syndrome is most common in sexually mature male umbrella cockatoos (different from review paper which states female, Umbrella cockatoos)
Also seen in females, other cockatoos, and African grey parrots
Acute management of cloacal prolapse = 2-3 transverse sutures between ent lips to reduce opening
Rectal opening in psittacines is on the right side (unlike pigeons, chickens, and birds of prey)
- Ways to surgically manage cloacal prolapse:
Name
Technique
Notes
Percutaneous cloacopexy
Sutures placed percutaneously to adhere cloaca to abdominal wall
Does not alter vent and will re-prolapse
Coelomic cloacopexy
Suture from craniolateral urodeum around ribs +/- sutured to abdominal incision
Invasive
Incisional cloacopexy
Incise the serosal surface of the coprodeum then suture to abdominal wall
Invasive
Incisional colopexy
Tack colon to abdominal wall
Invasive
Cloacoplasty
Excise two triangular wedges bilaterally at vent edges, then suture
Reduces cloacal opening but intermittent prolapse can still occur
Conclusions: Asymmetrical cloacoplasty can successfully resolve chronic cloacal prolapse in cases of mild idiopathic cloacal prolapse. Creates a midline physical barrier not present in symmetrical cloacoplasties.
Egg binding - Common species?
Most common cause of dystocia?
Recommended management?
Percloacal Ovocentesis in the Treatment of Avian Egg Binding: Review of 20 Cases
Tariq Abou-Zahr, Daniel Calvo Carrasco, Sara Louise Jones, Thomas Anthony George Dutton
J. of Avian Medicine and Surgery, 33(3):251-257 (2019).
Common species: Psittaciformes >>> Accipitriformes = Strigiformes > Anseriformes
Common signs: unproductive straining, blood from cloaca, lameness, dyspnea, anorexia, coelomic distention
Most common cause of dystocia = oversized egg
Recommended management:
Confirmed presence of egg via rads or palpation/gross visualization of egg in cloaca
SC or IV fluids, butorphanol, calcium gluconate
If not obstructed (dystocia) - oxytocin 5-10U/kg IM
Dark enclosures, towels, 35-30F ambient temp
Anesthetized with isoflurane and placed in dorsal recumbency
Percloacal ovocentesis had good success (80%)
Complications = egg fracture, coelomitis
Conclusions: Dystocia most commonly occurred in psittacines secondary to an oversized egg and percloacal ovocentesis has good success.
Factors associated with unsuccessful outcomes in birds with closed mid-diaphyseal fx managed via tape splines?
Retrospective Evaluation of Tibiotarsal Fractures Treated With Tape Splints in Birds: 86 Cases (2006-2015).
Wright L, Mans C, Olsen G, Doss G, Amene EW, Britsch G, Christman J, Heatley J.
J Avian Med Surg. 2018 Sep;32(3):205-209.
Key Points:
Species: Psittaciformes > Passeriformes > Columbiformes
Causes: Unknown > owner mishandling > falling of a perch > dog/cat attack
Most fractures were mid-diaphyseal and closed
Tape splints were used in 92% of cases often without an intramedullary pin.
Factors for unsuccessful outcomes: removing the original tape splint before 14 days, deep pain loss, dog/cat attack.
Location of fracture was not associated with different outcomes
Conclusions: Tape splint external coaptation has a high rate of success in tibiotarsal fractures under 200 g.
What are the four articulations of the avian stifle?
What two nerves course along the lateral stifle?
What are the pros and cons of the following?
External coaptation
Transarticular external fixation
IM Pins
Permanent arthrodesis
Intra-articular/extra-capsular repairs
A Novel Surgical Approach to Avian Femorotibiotarsal Luxation Repair
McRee AE, Tully TN Jr, Nevarez JG, Sumner J, da Cunha AF.
J Avian Med Surg. 2017 Jun;31(2):156-164.
Key Points:
Avian stifle (4 articulations): proximal tibiotarsus, fibular head, medial and lateral condyles of femur
Supporting structures: medial and lateral collateral ligaments, cranial and caudal cruciate Ligaments, menisci, joint capsule, patellar ligament
Tibial and fibular nerve (branch of ischiadic nerve) course along lateral stifle
Fibular n → craniolateral crus and pes = tarsal flexion, digital extension
Tibial n → extensors of tarsus and digital flexors
Disadvantages of methods of fixation/stabilization
External coaptation – inguinal web limits proximal bandage/splint,
Transarticular ESF – risk of iatrogenic fracture of femur or tibiotarsus during pinning, longer anesthesia/sx, higher risk of osteomyelitis
FESSA (pigeons) – Decreased ROM, regressive lameness, pododermatitis, muscle atrophy
IM pinning – penetration of articular cartilage, risk of septic arthritis, decreased ROM
Permanent arthrodesis if irreparable damage to joint – Chronic ambulation difficulty
Intra-articular/extra-capsular – Disruption cartilage & ankylosis
No fabella (unlike in dogs) so need modified anchor (screw in this case) if want to stabilize drawer
Summary: Clinical report of a cockatoo with stifle luxation repaired via modified extracapsular (lateral) suture technique, which established a normal perching angle within 3 months post-op with joint ankylosis. Complication of screw migration.
Location of lipogenesis in psittacines?
Unique lipoproteins of birds?
What is the main cholesterol carrier in birds?
CardioChek POC analyzer for measurement of cholesterol - does it underestimate or overestimate? Accuracy?
What two factors strongly increased bias?
Comparison of a Point-of-care Cholesterol Meter With a Reference Laboratory Analyzer in Companion Psittaciformes
Barboza T, Beaufrère H
J Avian Med Surg. 2019 Mar 25;33(1):7-14.
Background:
- Hypercholesterolemia and dyslipidemia is relatively common in captive psittacine birds
- Associated with atherosclerosis, cardiovascular disease, reproductive disease, obesity, and xanthomas
- Risk factors: age, female sex, concurrent reproductive disease, and certain genera
- Differentials for hypercholesterolemia: postprandial synthesis, nutritional imbalances, lack of physical activity, vitellogenesis in female birds
- In psittacines, triglycerides are produced in the liver and lipogenesis is only in adipose tissue
- Bird birds have some unique lipoproteins, such as vitellogenin and very low-density lipoprotein yolk labeled (VLVLy)
- Birds lack lipoprotein (a), apolipoprotein E (ApoE), and apolipoprotein B48 (ApoB48)
- HDL is the main cholesterol carrier in birds, unlike LDL in people.
- This study defined hypercholesterolemia as >8 mmol/L (or 390 mg/dL)
Key Points:
- Accuracy of laboratory analyzer (Cobas) was adequate
- Point-of-care analyzer (CardioChek) tended to underestimate cholesterol and lacked accuracy
- Lipemia and hemolysis strongly increased bias
- PCV, glucose, and genus had no effect on bias
- Using the CardioChek could result in false negatives for hyperlipidemia
Conclusions: The CardioChek point-of-care analyzer lacks accuracy and cannot be used without specific reference intervals.
What blood values increases with increased estrogen levels and may be used as an alternative to direct estrogen measurement in birds?
CardioChek vs Accutrend?
Method Comparison Using 2 Point-of-Care Meters and a Reference Analyzer for Measuring Blood Triglycerides in Psittacine Birds
Katherine L. Irvine, Christoph Mans, Kristen R. Friedrichs
Journal of Avian Medicine and Surgery 33(3):229–234, 2019
In birds, blood triglyceride (TG) concentrations increase w/ increased estrogen levels, may be used as alternative to direct estrogen measurement.
When measuring triglycerides in psittacine samples:
CardioChek had high correlation and reasonable agreement with reference analyzer
Accutrend had poor, erratic performance.
Conclusions: If you are measuring triglycerides as a proxy for estrogen levels in psittacines without a reference lab, use a CardioChek.
Which diagnostic is more sensitive for Macrorhabdus ornithogaster? fecal PCV vs wet mount?
How to collect sample?
Comparison of Two Methods for Determining Prevalence of Macrorhabdus ornithogaster in a Flock of Captive Budgerigars (Melopsittacus undulatus)
Sullivan PJ, Ramsay EC, Greenacre CB, Cushing AC, Zhu X, Jones MP.
Journal of avian medicine and surgery. 2017 Jun;31(2):128-31.
Background:
M. ornithogaster = ascomycetous yeast.
Most common in budgies, parrotlets, lovebirds, canaries, finch species
Key Points:
Fecal PCR is more sensitive than fecal Gram Stain to detect M. ornithogaster. Negative fecal Gram Stain not definitive.
Fecal samples:
Fresh fecal Gram Stain preparations
Pool several days of feces for M. ornithogaster PCR
M. ornithogaster found in most healthy budgies
Conclusions: Use PCR to diagnose Macrorhabdus ornithogaster in budgies over a fecal wet mount.
Compare DV vs VD radiographic views of macaws - Visualization of cardiohepatic silhouette, intestines, PV, ventriculus, lungs, air sacs?
Cardiac and hepatic widths were larger for which view?
Comparison of Dorsoventral Erect and Ventrodorsal Supine Radiographic Views for the Evaluation of Intracoelomic Organs in Clinically Normal African Grey Parrots (Psittacus erithacus)
Graham Zoller, Lucile Chassang, Olivia van Steyvoort, Minh Huynh
J. of Avian Medicine and Surgery, 33(3):218-228 (2019).
- In dorsoventral erect radiographs of macaws (compared to ventrodorsal):
- Better visualization of cardiohepatic silhouette , intestines, proventriculus, ventriculus
- Worse visualization of lungs, air sacs
- More motion artifact, limb superimposition
- Wider liver
- Larger heart
- Both protocols had good views of the heart
- CT of red-tailed hawks and humboldt penguins had increased lung density in sternal recumbency
Dorsoventral erect
Ventrodorsal
Proventriculus visibility
Better visualized
Ventriculus visibility
Difficult to evaluate but better visualized
Difficult to evaluate
Cardiac-thoracic width ratio
Larger
Smaller
Hepatic width
Larger
Smaller
Parabronchi visibility
Better visualized
Air sac volume
Larger
Conclusions: In macaws, the dorsoventral radiograph visualizes visceral organs better while ventrodorsal recumbency visualizes the respiratory system better.
Which type of tape is least likely to cause permanent damage to feathers? What qualities of that type of tape make it better? Which tape was the worst?
Comparison of Feather Damage Associated With the Application of Pressure-sensitive Adhesive Tapes
Andrew G. Hill
J. of Avian Medicine and Surgery, 34(3):268-273 (2020).
Key Points:
- Damage is likely due to stiffness of tape’s backing and degree of adhesion to feather barbs
- Micropore surgical tape (MST) and Scotch blue original painter’s tape (SBOPT) were most appropriate, followed by Transparent tape (TT) and Nitto Denko Yu-Ki Ban nonwoven cloth tape (YBNWT)
- Transpore surgical tape (TST) is NOT recommended
- MST is the least likely to cause permanent damage
Conclusions: The higher the flexibility of the backing and lower adhesion means the better tape on the feathers. Micropore surgical tape performed the best and transpore surgical tape (human) is the worst.
COX selectivity of meloxicam?
Which avian spp have a long half-life for meloxicam?
What is N-acetyl-β-d-glucosaminidase (NAG)?
At 1.6 mg/kg x 7 days, what was observed in regards to NAG in AGs?
Pharmacokinetics of meloxicam during multiple oral or intramuscular dose administration to African grey parrots
Montesinos A, Encinas T, Ardiaca M, Gilabert JA, Bonvehí C, Orós J.
American journal of veterinary research. 2019 Feb;80(2):201-7.
Background:
- Meloxicam is COX-2 selective but binds to COX-1 at high dosages
- Half life in avian species: chickens, pigeons >>>> ostriches, ducks, turkeys
- N-acetyl-β-d-glucosaminidase (NAG) = lysosomal enzyme released into blood and urine when cell necrosis occurs
- Indicator of acute renal injury in mammals and birds
Key Points:
- Accumulation of meloxicam in Amazons administered 1.6 mg/kg over 7 days
- At 1.6 mg/kg dosage, urine and blood NAG increased but not outside of reference intervals
- No signs of illness or any other clin path changes
Conclusions: Repeated dosing in African grey parrots at 1.6mg/kg caused a light increase in plasma and urine NAG but no clinical adverse effects.
Describe the pharmacokinetics of SR meloxicam after SC adminsitration to HAPs? Adverse effects?
Pharmacokinetics of a Sustained-release Formulation of Meloxicam After Subcutaneous Administration to Hispaniolan Amazon Parrots (Amazona ventralis)
Guzman DS, Court MH, Zhu Z, Summa N, Paul-Murphy JR.
J Avian Med Surg. 2017 Sep;31(3):219-224.
Meloxicam SR is commercially available from Wildlife Pharmaceuticals
Pharmacokinetic study in Hispaniolan Amazon parrots (n=12) administered 3mg/kg SC
Half life ranged from 12 to 96 hours
4 birds has noticeably rapid declines in plasma meloxicam concentrations at 12 hours (<2mcg/mL compared to >10mcg/mL in other birds)
Significantly higher plasma half-life, AUC, and Cmax in “slow” parrots (n=8)
No difference in tmax
Injection site mild hematomas and white crusts noted
Conclusion: Meloxicam sustained release administered at 3mg/kg SC in Hispaniolan Amazon parrots had a half life of 12 to 96 hours with significant interindividual variability.
What occurred in cockatiesl administered LPS injections?
Which NSAID lead to lowest prostaglandin E levels?
Which NSAID reduced clinical signs the most?
Development of an In Vivo Lipopolysaccharide Inflammation Model to Study the Pharmacodynamics of COX-2 Inhibitors Celecoxib, Mavacoxib, and Meloxicam in Cockatiels (Nymphicus hollandicus)
Elke Gasthuys, Renee Houben, Roel Haesendonck, Siegrid De Baere, Joachim Morrens, Gunther Antonissen
Journal of Avian Medicine and Surgery 33(4):349–360, 2019
Background:
- NSAIDs competitively inhibit cyclooxygenase (COX) enzyme activity
- COX-1 → gastric protection, regulation of homeostasis, renal blood flow, platelet aggregation, in most tissues
- COX-2 → vasodilation, increased vascular permeability, chemotaxis, hyperalgesia, potentiates histamine; Induced in response to inflammation
- Meloxicam = preferential COX-2 inhibitor at low doses but COX-1 at high doses
– Side effects such as GI tox, CV effects, nephrotoxicity
- Celecoxib, mavacoxib - selective COX-2 inhibitors that do not alter COX-1 activity.
- Lipopolysaccharide (endotoxin) → immune response → change in body temp, cytokine production, signs of illness
Key Points:
- Cockatiels given 2 LPS injections at 1-day intervals → pronounced hypothermia
- Control LPS and meloxicam groups had: Hypothermia, Obtundation (also in celecoxib), Ruffled feathers
- Prostaglandin E levels: control > mavacoxib > celecoxib > meloxicam
- PGE levels did not correlate with clinical illness seen
Conclusions: Mavacoxib reduced clinical signs the most but meloxicam decreased prostaglandin levels the most in cockatiels administered lipopolysaccharides.
Describe PK and PD of hydromorphone in cockatiels? In kestrels?
Evaluation of the thermal antinociceptive effects and pharmacokinetics of hydromorphone hydrochloride after intramuscular administration to cockatiels (Nymphicus hollandicus).
Houck EL, Guzman DS, Beaufrère H, Knych HK, Paul-Murphy JR
Am J Vet Res. 2018 Aug;79(8):820-827
Results/Discussion:
Sedation observed at with 0.3 and 0.6 mg/kg
No significant change in thermal withdrawal threshold at any time
The plasma hydromorphone concentration remained > 6 ng/mL for at least 3 hours and decreased to < 1 ng/mL (ie, the therapeutic concentration for most other species) by 6 hours after IM drug administration.
Shorter half life in the cockatiels (0.99 hours) compared to kestrels (1.26 hours) at the same dose and route.
In American kestrels, IM administration of hydromorphone at 0.1, 0.3, and 0.6 mg/kg increased the thermal nociception threshold for 3 to 6 hours; however, some birds developed moderate to severe sedation when administered the highest dose.
Conclusion: Despite plasma drug concentrations considered therapeutic for other species, IM administration of hydromorphone at 0.1, 0.3, and 0.6 mg/kg did not significantly affect the thermal withdrawal threshold of cockatiels but did produce significant sedation at the 0.3- and 0.6-mg/kg doses.
Describe PD of hydromorphone in kestrels, cockatiels, and orange-winged amazon parrots.
Adverse effects in OWAPs?
Evaluation of the thermal antinociceptive effects of hydromorphone hydrochloride after intramuscular administration to orange-winged Amazon parrots (Amazona amazonica)
Sanchez-Migallon Guzman D, Douglas JM, Beaufrère H, Paul-Murphy JR.
American journal of veterinary research. 2020 Oct;81(10):775-82.
Background:
Hydromorphone PD Review:
American kestrels at 0.1, 0.3, 0.6 mg/kg had increased thermal threshold + sedation at higher doses
Cockatiels at up to 0.6 mg/kg had no change in thermal threshold + mild sedation
Key Points:
Thermal withdrawal threshold increased with hydromophone:
For 0.5 - 3 h at 1 mg/kg
For 1.5 - 6 h at 2 mg/kg
Increased agitation score (nausea, miosis, ataxia) at 1 and 2 mg/kg for 3 hours
Regurgitation (n=1)
Changes in thermal threshold change greater with hydromorphone than butorphanol in this species.
Conclusions: Orange winged amazon parrots showed significant increase in thermal foot withdrawal with 1mg/kg & 2mg/kg hydromorphone IM but also had increased agitation.
Describe PK and PD of hydromorphone in orange-winged amazon parrots.
Pharmacokinetics of hydromorphone hydrochloride after intramuscular and intravenous administration of a single dose to orange-winged Amazon parrots (Amazona amazonica)
Sanchez-Migallon Guzman D, Knych H, Douglas J, Paul-Murphy JR.
American journal of veterinary research. 2020 Nov;81(11):894-8.
Hydromorphone: a μ-opioid receptor agonist with 5 to 7 times the potency of morphine
Does not cause histamine release when administered IV
Hydromorphone did not change thermal withdrawal response in cockatiels at 0.1, 0.3, and 0.6 mg/kg IM
Hydromorphone at 1 and 2 mg/kg IM increased thermal foot withdrawal thresholds in orange-winged Amazons
But caused agitation, nausea, beak opening, moving the tongue back and forth, ataxia, miosis
Very short half-life (1.74 h) and rapid plasma clearance
Conclusions: Hydromorphone in orange-winged Amazons increases thermal withdrawal but causes adverse effects (agitation, ataxia) and has rapid PK parameters.
What is the mechanism of buprenorphine?
PD in kestrels? AG parrots? Timneh parrots?
Cockatiels?
Evaluation of the thermal antinociceptive effects and pharmacokinetics after intramuscular administration of buprenorphine hydrochloride to cockatiels (Nymphicus hollandicus).
Guzman DS, Houck EL, Knych HK, Beaufrère H, Paul-Murphy JR.
American journal of veterinary research. 2018 Dec;79(12):1239-45.
Buprenorphine, a μ-opioid receptor agonist and κ- and δ-opioid receptor antagonist
Increased thermal withdrawal in American kestrels for 6 hours with 0.1, 0.3, 0.6 mg/kg IM
0.6 mg/kg exceeded target concentrations for 9 hours
No increase in thermal withdrawal thresholds in African grey parrots and Timneh parrots at 0.1 mg/kg IM
Conclusions: Buprenorphine at 0.6, 1.2, 1.8 mg/kg IM did NOT affect thermal-withdrawal threshold or agitation-sedation scores in cockatiels.
Butorphanol has analgesic effects in what spp?
No analgesia in what spp?
MAC sparing in which spp?
Adverse effects in HAPs?
PK of SC injections vs IM in HAPs?
Pharmacokinetics of butorphanol tartrate in a long-acting poloxamer 407 gel formulation administered to Hispaniolan Amazon parrots
Laniesse D, Guzman DS, Knych HK, Smith DA, Mosley C, Paul-Murphy JR, Beaufrère H
American journal of veterinary research. 2017 Jun;78(6):688-94.
Background:
Butorphanol is a kappa opioid receptor agonist and a mu receptor antagonist
Analgesic effects in Amazon parrots, African grey, green cheeked conures
No analgesia in kestrels or cockatiels
MAC-sparing effect of isoflurane in Cockatoos and of sevoflurane in Hispaniolan Amazons and guinea fowl
Polyaxamer 407 is a thermosensitive hydrogel
Hydrogel = “reverse gelatin” = liquid at room temp and solid gel at body temps
Key Points:
Butorphanol-P407 was above therapeutic levels for 3-8 h
2 birds vomited at the approximate time Cmax of high dose
SQ injections resulted in a lower Cmax, but a longer duration in the blood compared to IM
Conclusions: Butorphanol in a long acting poloxamer 407 gel may provide analgesia for 4-8hours in Hispianiolan Amazon parrots.
PD of butorphanol P407 in HAPs? Adverse effects?
EVALUATION OF THE THERMAL ANTINOCICEPTIVE EFFECTS OF SUBCUTANEOUS ADMINISTRATION OF BUTORPHANOL TARTRATE OR BUTORPHANOL TARTRATE IN A SUSTAINED-RELEASE POLOXAMER 407 GEL FORMULATION TO ORANGE-WINGED AMAZON PARROTS (AMAZONA AMAZONICA)
Laniesse D, Sanchez-Migallon Guzman D, Smith DA, Douglas JM, Mosley C, Beaufrère H, Paul-Murphy
American Journal of Veterinary Research. 2020 Jul;81(7):543-50.
Key Points:
- Butorphanol IM vs control → significant difference of thermal thresholds at 30-90 min
- Butorphanol-P407 vs P407 → No significant difference of thermal thresholds
- Butorphanol-P407 was sedative
- But-P407 vs Saline → No significant difference of thermal thresholds.
Conclusions: Butorphanol has a small antinociceptive effect in orange-winged Amazons but butorphanol-P407 was not effective.
What is the mechanism of action of amantadine?
PK of amantadine in OWAPs?
Pharmacokinetics of amantadine after oral administration of single and multiple doses to orange-winged Amazon parrots (Amazona amazonica)
Berg KJ, Sanchez-Migallon Guzman D, Knych HK, Drazenovich TL, Paul-Murphy JR.
American journal of veterinary research. 2020 Aug;81(8):651-5.
Background:
Amantadine - NMDA antagonist (increases dopamine release in CNS), decreases tolerance to opioid medications
Helps decrease central sensitization (response of sensory neurons to noxious and non-noxious stimuli)
Key Points:
Single oral dose of 10mg/kg - above therapeutic concentration for up to 48 hours
Multiple dose 5mg/kg PO q24h x 6d - above target concentration for at least 24h
Accumulation index was low for multiple doses
No adverse effects
Conclusions: Amantadine lasts for 48 h after a single 10 mg/kg dose and 24h after 5 mg/kg dose
What area of the GIT is most commonly affected by macrorhabdus ornithogaster?
Does yeast load correlate with severity of dz?
What is the most specific clinical sign in budgies?
Sex predilection?
Was amphotericin B effective in a review of budgie infections in a veterinary clinic?
The Incidence and Treatment Outcomes of Macrorhabdus ornithogaster Infection in Budgerigars (Melopsittacus undulatus) in a Veterinary Clinic
Püstow R, Krautwald-Junghanns ME.
Journal of avian medicine and surgery. 2017 Dec;31(4):344-50.
Background:
Macrorhabdus ornithogaster: anamorphic, ascomycetous, weakly Gram + yeast
Found in healthy animals but disease with stressors
Signs: vomiting, diarrhea, weight loss with a good appetite, undigested seeds in feces
Poor prognosis if melena
+/- dilated proventriculus
Necropsy: emaciation and hemorrhagic, ulcerative proventriculitis
Most commonly affects the glands of the isthmus
Diagnose with examination of fresh feces
Yeast load does not correlated with severity of disease
Low sensitivity due to intermittent shedding
Treatment only if clinical signs
Often resistant to nystatin
Amphotericin may be more effective but a more stressful treatment regimen
Key Points:
Most specific sign of M. ornithogaster in budgies = undigested seeds
Proventricular dilation difficult to see on radiographs
Most common in males
No age predilection
Amphotericin B was not consistently effective and was very stressful
Prevalence of M. ornithogaster is associated with co-occurrence of other pathogens
Conclusions: Macrorhabdus ornithogaster causes gastrointestinal (especially undigested seeds) and there is not an ideal treatment regime.
Efficacy of amphotericin B in drinking water for cockatiels and budgies?
COMPARISON OF TWO TREATMENT MODALITIES AND PCR TO ASSESS TREATMENT EFFECTIVENESS IN MACRORHABDOSIS
Poleschinski JM, Straub JU, Schmidt V.
Journal of Avian Medicine and Surgery. 2019 Sep;33(3):245-50.
Background:
Macrorhabdus ornithogaster = anamorphic ascomycetous yeast commonly in proventriculus of psittacines.
Signs: Lethargy, vomiting, diarrhea, undigested seed, weight loss
Death often from aspiration after regurgitation, proventricular ulceration
Diagnosis: microscopic exam or PCR of feces
Key Points:
Most common clinical signs = gastrointestinal
Also polyuria/polydipsia (n=9)
About half (56.4%) tested negative after amphotericin B water treatment
Combination amphotericin B in drinking water & oral administration→ 62.5% M ornithogaster DNA - negative fecal samples
No statistically significant differences between 2 treatment options evaluated
No difference in treatment protocols, age, sex, body weight
Conclusions: Amphotericin B in drinking water x 28 days +/- orally administered x 10 days only reduced Macrorhabdus ornithogaster in half of budgies and cockatiels.
Flock treatment is not recommended, except in cases with significant morbidity and mortality
Feral Rosy-faced lovebirds had a high prevalence of what infectious disease?
CHLAMYDIA PSITTACI IN FERAL ROSY-FACED LOVEBIRDS (AGAPORNIS ROSEICOLLIS) AND OTHER BACKYARD BIRDS IN MARICOPA COUNTY, ARIZONA, USA
Edouard O. Maccolini, DV, IPSAV (Zoological Medicine), Philippe J. Dufresne, PhD, Sophie Ann Aschenbroich, DVM, Dipl ACVP, Brittany McHale, DVM, MPH, Julie-He ́le`ne Fairbrother, DVM, MSc, Dipl ACVM, Christian Be ́dard, DVM, MSc, Dipl ACVP, and Julie A. He ́bert, DVM, Dipl ABVP (Avian)
Key Points:
- Population of feral Rosy-faced lovebirds – estimated at 2500
- 18 birds died in 2013, 75 in 2014
- DNA positive, but antibody negative birds could reflect environmental exposure or contamination from sampling
- Lovebirds and pigeons remained with higher prevalences when that was considered
- Lovebirds also positive for both psittacine circovirus pathotypes 1 & 2 (2 is less virulent – found in lories which recovered well from disease)
Take Home: Rosy-faced lovebirds or rock doves in Arizona at feeders may be spreading Chlamydia psittaci. Other feral parrot populations may pose a similar risk for transmission.
Name a non-albicans candida associated with GI dz in birds.
Donnelly, K. A., Wellehan Jr, J. F., & Quesenberry, K. (2019). Gastrointestinal disease associated with non-albicans Candida species in six birds. Journal of Avian Medicine and Surgery, 33(4), 413-418.
- Candida glabrata and Candida krusei identified as causative agents of GI dz in birds.
- Behavior is similar to Candida albicans. Related to previous tx with abx.
- Treatment with terbinafine 15 mg/kg PO q24h x 6 wks was successful in one individual. Fluconazole 20 mg/kg PO q12h x 14d +/- nystatin for 28 days successful others.
- Diagnosis achieved with cytology or histo i.e. fecal or crop Gram’s stain, culture.
- Part of normal mycoflora, so ID on cytology is not sufficient for dx without CS.
- C. glabrata is more commonly being diagnosed in humans in hospital settings, supports role of abx and immunosuppression as risk factors for infection. Second most common vs C. albicans in humans.
- Spp ID of Candida can be performed with MALDI-TOF (mass spec) technology.
Takeaways: C. glabrata and C. krusei (non-albicans Candida spp) may be up and coming pathogens. Empirical use of abx and immunosuppression likely contributing to onset of Candida overgrowth and clinical signs of disease.
Hébert, J. A. (2019). Closed Reduction of a Rostroparasphenopalatal Luxation in a Red-crowned Parakeet (Cyanoramphus novaezelandiae). Journal of avian medicine and surgery, 33(3), 285-288.
What is the benefit of performing a laterolateral closure for tail amputation for surgical removal of a uropygial gland adenocarcinoma?
Modified Tail Amputation Technique in a Blue and Gold Macaw (Ara ararauna) With Uropygial Gland Adenocarcinoma.
Robertson, J., Guzman, D.S.M., Sinnott, D., Woolard, K., Nesset, A. and Paul-Murphy, J.R.
Journal of avian medicine and surgery, 2020;34(1):57-64.
- Uropygeal gland tumors: carcinoma (SCC), adenomas, and adenocarcinomas; other ddx adenitis, Vit A deficiency with glandular metaplasia
- Surgical resection (except water birds) +/- post-op radiation (strontium 90) or chemo
- Previously described dorsoventral closure
Key Points
- Surgical resection of locally invasive uropygial gland adenocarcinoma with pygostyle amputation
- Laterolateral closure reduced tension and resulted in more ventral position of vent reducing post-op contamination of surgical site
- Euthanized ~4 mo post-op, had healed well but was found minimally responsive and dyspneic
Conclusions
- Novel surgical technique reported for locally invasive uropygial gland adenocarcinoma involving pygostyle amputation and reduction of lateral vertebral processes with laterolateral closure
- Reduces tension and post-op contamination due to more ventral vent position
Compare the chemiluminescent immunoassay with the radio immunoassay for measurement of thyroid hormones in macaws.
Journal of Avian Medicine and Surgery 35(2):187–195, 2021
Comparison of Serum Thyroid Hormone Levels in Greenwinged Macaws (Ara chloropterus) Using Radio and Chemiluminescent Immunoassays
Ka ́ssia R. A. Vieira, MS, Ana C. L. Faillace, MS, L ́ıgia R. Oliva, DVM,Mathias Dislich, DVM, Zalmir S. Cubas, MS, Adalfredo R. Lobo-J ́unior, PhD,and Marcelo I. S. Santana, PhD
Radioimmunoassay is considered the method of choice in measuring total T4 and T3 in birds, but it has a high limit of detection for the typically low concentrations of thyroid hormones in birds
The chemiluminescent immunoassays have good sensitivity, long shelf life, and don’t produce radioactive waste and have been used in people, dogs, cats, horses, and guinea pigs
Females had higher concentrations of T3 – estrogen upregulates pituitary T3 receptors, and higher levels of total and free T4, and TSH are observed in women as well
· Differences in avian thyroid physiology
Lack thyroxine binding globulin (T3/T4 transport protein) so hormone levels are less affected by plasma protein levels; other plasma proteins have a much lower binding affinity to T3 compared with T4
Limits of the canine CLIA – all values of T4 were the same (human products have been successfully used); TSH levels had the greatest variability but levels are near the limits of detection for both tests
Take Home: The CLIA is consistent with RIA in measuring T3 levels but not T4 or TSH.
Risk factors for atherosclerosis in parrots?
Role of fructose?
Béland, K., Ferrell, S. T., Beaufrère, H., Lair, S., & Desmarchelier, M. (2021). Impact of Dietary Fructose on the Lipid Profile in Six Macaws. Journal of Avian Medicine and Surgery, 35(2), 196-203.
Atherosclerosis in parrots
o Characterized by deposits of lipids, collagen, inflammatory cells, calcium salts, cellular debris within intima media of arteries
o CS – lethargy, weakness, exercise intolerance, balance loss, difficulty perching, feather destructive behavior, self-mutilation, claudication-like syndrome, neurological signs, respiratory distress, sudden mortality
o Risk factors – age (20-30 years), genus (Psittacus, Amazona, Nymphicus), sex (usually female)
§ Hypercholesterolemia, hypertriglyceridemia, elevated LDL-C, decreased HDL-C (increases in birds put on an exercise regimen). Linked to dyslipidemia
o Birds carry most cholesterol as HDL-C rather than LDL-C in humans; they also use portomicrons rather than chylomicrons to transport triglycerides (fat transported by vesicles directly to bloodstream rather than through lymphatics first like in mammals); estrogen upregulated lipoproteins for vitellogenesis
o Birds fed high cholesterol diets can have atherosclerosis induced
· Role of fructose - Simples sugars are linked to atherosclerosis in humans
o Fructose is primarily absorbed by hepatocytes and metabolized by fructolysis which skips the phosphofructokinase step of glycolysis where most glucose regulation happens – meaning the liver metabolizes fructose as long as it is available – which results in a lot of fatty acid synthesis
· This study failed to find changes with the short duration of fructose administration
o Birds also had access to each other’s bowls so things were not as controlled as they should have been
Take Home: Excessive fructose may be an additional risk factor for atherosclerosis in avian species
What technique is considered the best for in-clinic testing for macrorhabdus detection?
Baron, H. R., Stevenson, B. C., & Phalen, D. N. (2021). Comparison of In-Clinic Diagnostic Testing Methods for Macrorhabdus ornithogaster. Journal of Avian Medicine and Surgery, 35(1), 37-44.
Macrohabdus ornithogaster
o Yeast found primarily in the isthmus between proventriculus & ventriculus
o 20-80 micrometer long, strait rods with rounded ends and a refractile nuclei
o Typically present on the surface of the isthmus, but can penetrate the glands of the proventriculus and the koilin of the ventriculus in severe cases using in a lymphoplasmacytic ventriculitis
o CS – vomiting, dark tarry feces, chronic wasting, death – or asymptomatic
o Diagnostics – PCR is better than gram stain, mini-FLOTAC is comparable to gram stain
· This study – macrosuspension was the best in-clinic diagnostic; detection at follow-up is better than at the end of treatment
Take Home: Macrosuspension technique is the best in-clinic testing for macrorhabdus detection
Relationship between body weight and mortality following administration of iodinated contrast medium for CT in birds?
McCready, J. E., Gardhouse, S. M., Appleby, R., & Beaufrěre, H. (2021). Mortality rate of birds following intravenous administration of iodinated contrast medium for computed tomography. Journal of the American Veterinary Medical Association, 259(1), 77-83.
- only 6 deaths during 131 contrast-enhanced CT examinations
- Decreasing body weight significantly increased odds of death by 83% per 100 g after contrast medium administration
- small birds (body weight ≤ 150 g) had significantly increased odds of dying shortly following administration of contrast medium, compared with larger bird
- overall rate of death - 4.6%
- large birds – 0.8%
- small birds - 45.4%
- present study - evidence that bolus injection of nonionic iodinated contrast medium associated with substantial rate of deaths in small unhealthy psittacines
- birds with respiratory disease may be at increased risk of death following contrast medium admin or simply have an increased risk of dying in general
Young budgies are highly susceptible to death by this virus. Nonbudgie nestlings typically develop normally.
- AKA Budgie fledgling disease.Similar signs to PBFD.
- Respiratory exposure leads to viremia even in asymptomatic birds.
- Many infections are asymptomatic
- Virus shed in droppings, secretions, and feather dander.
- Disease and death due predominantly in nestlings < 14 weeks old.
- Budgies, lovebirds, macaws, conures, caiques, eclectus, and ring-necked parrots.
- Cockatoos, Amazons, and African grays uncommon.
- Lesions – stunted growth, abnormal feathers
- hydropericardium, myocardial hemorrhage, ascites, hepatomegaly, hepatic necrosis, renal swelling, petechial, and general tissue pallor.
- Histo: Enlarged nuclei (karyomegaly) and have granular, basophilic to amphophilic inclusion – spleen, liver, kidney.
- Nonbudgie nestling psittacines typically develop normally
- But fatal infections can occur.
Causative agent of Pacheco’s Dz?
Pathology and clinical signs?
- Pacheco’s disease (PD) - peracute to acute cause of fatal hepatitis in psittacines.
- Caused by psittacid herpesvirus type 1 (PsHV-1)
- Alphaherpesvirus closely related to infectious laryngotracheitis virus.
- 4 genotypes
- Amazons most commonly infected – all 4 genotypes
- African greys – genotypes 2-4 (not 1)
- Genotype 4 is most commonly associated disease in macaws and conures
- genotype 3 is rare and genotype 1 has not been found in these species
- Cockatoos seem refractory to disease
- Clinical signs minimal or absent. Birds die in good condition.
- Necropsy: enlarged, mottled, friable, hemorrhagic liver.Crop also affected.
- DDX: bacterial hepatitis, chlamydiosis, lead poisoning, polyomavirus, adenovirus, and reovirus
- Histo: Hepatic necrosis, intranuclear inclusion bodies – deeply eosinophilic
- Not all infections cause disease.Some birds are asymptomatic carriers.
- Caused by psittacid herpesvirus type 1 (PsHV-1)
- PsHV-1 associated mucosal papillomas – NW birds
- PsHV-2, has been identified in cutaneous papillomas in African greys
- PsHV-1, 2, and 3 (but not 4) have been identified in mucosal papillomas
Causative agent of proventricular dilatation disease?
- Proventricular Dilatation Disease (PDD) – cause by Avian Bornavirus.
- Nine pathogenic genotypes. Has been isolated from healthy animals.
- Not reported in free ranging birds.
- Clinical signs: ileus, severe emaciation with marked pectoral muscle & adipose atrophy
- Gross: flaccidity and dilatation of any portion of the GI tract.
- Proventriculus, ventriculus, and crop being most common
- Often filled with seeds
- Histo: lymphoplasmacytic inflammation
- Myenteric plexus of esophagus, crop, or GI tract
- Inflammatory infiltrate
- Proventricular dilatation is characteristic, but not pathognomonic
- Other differentials – clostridial infections, gastric mycobacteriosis, fungal gastritis, lead toxicity, peritonitis or serositis, ulcerative/erosive gastritis
- Nine pathogenic genotypes. Has been isolated from healthy animals.
This bacteria causes high mortality in lorkeets and African greys. Transmission by ingestion of contaminated food or water, aerosolization of feces or feather dust.
- Gram negative bacilli – Enterobacteriacea
- S. typhimurium – high mortality in lories & African greys
- Transmission by ingestion of contaminated food or water or aerolization of feces or feather dust
- Feces from carrier birds most common
- Clinical signs: depression, lethargy, anorexia, weight loss, diarrhea, pasty vents, lameness, abscess formation, convulsions, poor hatching or excessive fledgling mortality, dehydration & crop stasis, meningitis, osteoarthritis, suddent death.
- Gross: hepatosplenomegaly, pneumonia, catarrhal to hemorrhagic enteritis
- Histo: mulifocal random necrosis & heteropohilic to. Lymphohistiocytic inflammation
- GI tract, liver, spleen
- Gram negative bacilli – Enterobacteriacea
Describe the bi-phasic lifestyle of chlamydia
- Chlamydia psittaci
- Obligate intracellular, Gram-negative, zoonotic bacterium
- Biphasic life cycle – infective elementary body, replicative reticulate body
- Aerosol inhalation & ingestion are primary routes of transmission
- Clinical Signs:
- Young birds more susceptible than old birds
- Sinusitis, dyspnea, conjunctivitis, polyuria, diarrhea, lethargy, anorexia, yellow-green droppings, poor feathering, flaccid paralysis of the legs, chronic weight loss, opisthotonos, tremos.
- Increased in ovo deaths, decreased fertility, early chick death
- Hepatic & splenic enlargements
- Pericarditis and air sacculitis
- Hepatic & splenic enlargements
- Histo: lymphoplasmacytis and histiocytic inflammation – multifocal to confluent necrosis
- Stains with Giminez’s stain for intracellular organisms
Old world psittacines are highly susceptible to fatal respiratory dz from this parasite.
New world psittacines appear resistant as adults, but CS are reported.
- Sarcocystis falcatula
- Virginia opossum is the definitive host, cowbirds & grackles are the intermediate hosts
- Asexual reproduction occurs int eh endothelium of intermediate host, causing real damage in aberrant hosts
- Shcizogony is followed by the formation of sarcocysts in muscles
- New World psittaicnes appear resistant as adults, but CS are reported.Old World psittacines are highly susceptible to fatal respiratory disease
- Gross: severe pulmonary congestion, edema, hemorrhage
- Histo: fibrin, edema, & hemorrhage within the lungs; lymphoplasmacytis accumulation around blood vessels & bronchi; protozoal merozoites within pulmonary vessles
- Other forms
- Muscle – severe weakness & lethargy, elevated CK/AST, protzoal cysts in skeletal muscle with lymphoplasmacytis myositis
- Neuro – severe ataxia, incoordinated head movements.Schizonts within cerebellum & brainstem with lymphoplasmacytic meningoencpehlitis
- Virginia opossum is the definitive host, cowbirds & grackles are the intermediate hosts
Describe steps you can take to clear a flock of avian bornavirus.
- To clear flock, test all birds with direct/indirect tests
- Separate birds into 3 groups based on results – positive, questionable, negative
- Ethically, euthanasia of positive, non-clinical birds not recommended
- Retest questionable/negative groups 4-6 weeks later
- Continue testing and maintain separation until only negative birds remain
- Only quarantined, tested birds can enter flock
- Take eggs away from positive parents, disinfect, hand-raise and test
- ABV negative eggs common form positive parents
- If negative, can be given to foster parents
- May need to rehome positive, non-clinical birds
- Antibodies not protective and disease is immune-mediated
- Difficult to develop vaccine
- Antibodies not protective and disease is immune-mediated
Speer
Which herpesvirus is associated with Pacheco’s dz?
Which herpesvirus causes mucosal papillomas in Gray parrots only?
Which herpesvirus causes respiratory dz?
Necropsy findings of Psittacid Herpes 1?
Pacheco’s disease
- Most common in parrots – no age, sex, species predilection
* Macaws, amazons, cockatoos, African gray parrots are highly susceptible
* Some spp of conure appear to be subclinical shedders- Also found in passerines
- Most common in parrots – no age, sex, species predilection
- Clinical manifestation
- Acute, rapidly fatal
- Clinical signs are non-specific
- Biliverdin-stained urates prior to death (yellow/green)
- Blood work (if alive) – leukopenia, elevated AST
- Usually necropsy (due to acute mortality)
- Hepatic lipidosis, hepatomegaly, splenomegaly, multifocal hepatic necrosis, pancreatitis, enteritis
- Histopathology – pan-nuclear eosinophilic inclusions in liver/spleen
- Usually necropsy (due to acute mortality)
- Blood work (if alive) – leukopenia, elevated AST
- Acyclovir has been effective at preventing mortality
* 80-100 mg/kg PO q8h x10d- Birds that survive will be carriers of the virus
- Acyclovir has been effective at preventing mortality
Mucosal papillomatosis is associated with which herpesvirus in birds?
- Psittacid herpes 1
- Demographics
- Most prevalent in Amazons, macaws, conures, hawk-headed parrots; also found in other species
- Clinical manifestation
- Raised, pink, proliferative papillomas found in cloaca and oral cavity
- Oral: most often choanal margins or tongue base; rarely extend into upper GI tract; loss of pigmentation
- Diffuse cloacal lesions: cobblestone appearance
- Lesions may wax/wane, disappear completely, or become progressive
- Signs: dyspnea, straining to defecate, hematochezia, regurgitation, chronic wasting
- Diagnosis
- PE – oral/cloacal exam (evert with lubed CTA), crop thickening
- PCR – not usually nece
- ssary for papillomas
- Biopsy – not usually necessary for papillomas
- Histopathology – papillomas: multiple fibriae w/ fibrovascular core and cuboidal/columnar epithelial cells
- Raised, pink, proliferative papillomas found in cloaca and oral cavity
- Benign neglect if not causing clinical signs (may regress)
- Surgery – debulk w/ sharp dissection, laser surgery, radiosurgery; treat w/ topical silver nitrate
- Benign neglect if not causing clinical signs (may regress)
Which avian herpesvirus is associated with bile duct and pancreatic duct carcinomas?
This is a common sequelae of what clinical condition?
Bile duct and pancreatic duct carcinomas
- Common sequelae of mucosal papillomatosis
- Months to years after onset
- Clinical manifestation
- Chronic hepatic disease (weight loss, overgrown beak, poor feather quality)
- Does not seem to be metastatic
- Rads – hepatomegaly
- Ultrasound – multifocal to coalescing hyperechoic liver
- Blood work – elevated GGT
- Liver biopsy
- Rads – hepatomegaly
- Chemotherapy – case report of carboplatin in green-winged macaw
Which herpesvirus only infects Congo African grey parrots? Clinical signs?
Psittacid herpesvirus 2
Clinical manifestation
- Subclinical carriers
- Mucosal and mucocutaneous papillomas of oral cavity and eye (benign but can be extensive)
- r/o: parrot papillomavirus-1 (PePV-1) (rare; only reported in wild-caught birds)
Diagnosis
- Biopsy – fibropapillomatous lesions without viral inclusions
- PCR – oral/cloacal swabs
Treatment
- No reports of treatment attempts
- Surgical removal if lesions interfere w/ airflow
- Acyclovir will not be effective bc lesions are not thought to be associated w/ replicating virus
What herpesvirus is found in Bourke’s parrots in the USA and 2 eclectus in Australia? Clinical signs?
Psittacid herpesvirus 3
Demographics
- Found in Bourke’s parrots in USA and 2 eclectus parrots in Australia
Clinical manifestation
- Targets the trachea - upper respiratory signs (cough, dyspnea, oculonasal discharge)
- Non-specific signs (lethargy, anorexia, weight loss)
Diagnosis
- Antemortem – no work has been done
- Cytology of conjunctiva/trachea – syncytial cells w/ eosinophilic intranuclear inclusion bodies
- PCR – partial sequence is known
- Gross – conjunctivitis, tracheitis, changes associated w/ pneumonia and airsacculitis
- Histo – syncytial cells w/ eosinophilic intranuclear inclusion bodies in respiratory tract
- Gross – conjunctivitis, tracheitis, changes associated w/ pneumonia and airsacculitis
Treatment
- Acyclovir has been used
What is the gold standard for dx psittacine beak and feather disease?
- Hemagglutinating virus -> agglutinates erythrocytes from guinea pigs, geese, and many psittacine species
- BFDV exhibits host-generalism with wide species susceptibility
- Suspect Loriinae subfamily (lorikeets, lories, fig parrots, budgerigars) are more robust or host adapted
- Hemagglutination inhibition gold standard as it avoids cross-reactivity between different species
What is the most important virulence factor for chlamydia infection?
Describe transmission of chlamydia psittaci and replication.
- Toxin is most important virulence factor, which is bound to EBs
- Clinical infection depends on relationship between EBs and macrophages
- EBs can be found in feces, urine, tears, nasal discharge, oropharyngeal mucus, and crop milk
- Infection occurs by inhalation or ingestion of infectious particles
- Infection is rapid and C. psittaci will replicate in lungs, air sacs, pericardium 24 hours after infection
- Within 48 hours, in bloodstream
- Within 72 hours, bird can shed into environment
- Vertical transmission demonstrated in duck, black-headed gull, and budgies
- Direct transmission from dogs, cats, horses, pigs, humans to conspecifics does not occur
- EBs can be found in feces, urine, tears, nasal discharge, oropharyngeal mucus, and crop milk
A confirmed case of avian chlamydial infection is defined on the basis of what?
A probable case of avian chlamydia is defined as compatible illness and what?
A suspected case of avian chalmydial infection is defined as what?
A human is considered to be confirned if clinical illness is compatible with psittacosis and the case is confirmed by a lab with the use of one of which two methods?
A human is considered a probable case if the clinical illness is compatible and what laboratory results?
Infection in Humans (Psittacosis)
- Transmission – exposure to birds – human inhales organisms that have been aerosolized from dried feces or respiratory tract secretions
- Other means – mouth to beak exposure or handling plumage and infected tissues
- Adverse pregnancy outcomes have been reported
- Clinical signs – mild illness to severe pneumonia, typically starts with fever, chills, headache, malaise, myalgia; radiographs show interstitial infiltrates
- Diagnosis – MIF is more sensitive (cross-reactivity with other C species), PCR is more reliable (blood, tissues, respiratory secretions)
- Labs – CDC’s respiratory diseases division
- Tx – tetracycline
Infection in Birds (Avian Chlamydiosis)
- Excreted in ocular or nasal discharges or feces
- Can remain infective for a month in feces – shedding exacerbated by stress
- Clinical signs – lethargy, anorexia, ruffled feathers, conjunctivitis, ocular or nasal discharge, green urates
- Case definition
– Confirmed - isolation, PCR followed by sequencing, fourfold increase in titers, intracellular bacteria on tissue impression
– Suspected – Chlamydial PCR, fluorescent antibody swab, epidemiologically linked to a human case
- Diagnosis – many labs (see table)
A recent study investigated intranasal butorphanol and midazolam prior to IM alfaxalone for sedation of Quaker parrots.
What is the scientific name of the Quaker parrot?
What doses were used?
- What differences in sedation were noted?
- What differences in side effects were noted?
Intranasal butorphanol and midazolam administered prior to intramuscular alfaxalone provides safe and effective sedation in Quaker parrots (Myiopsitta monachus).
Conner CM, Hoppes SM, Stevens BJ, Simon BT.
American Journal of Veterinary Research. 2022;83(12).
Background
- Alfaxalone - neuroactive steroid anesthetic, acts on y-aminobutyric acid subtype A (GABAA)
– Alfaxan Multidose IDX recently added to US FDA Index of Legally Marketed Unapproved New Animal Drugs for Minor Species with an indexed indication for sedation and anesthesia of Psittaciformes
– IM alfaxalone in Quaker parrots had potential hyperexcitation and muscle tremors, reduced but not abolished with IM midazolam premedication
– IM alfaxalone alone had dose dependent sedation in budgies, SQ alone allowed radiographs in black-cheeked lovebireds, dose-dependent reduced induction time and increased anesthesia duration in Bengalese finch, IV had shorter, smoother induction than iso facemask and reduced iso requirements during ortho sx of flamingos
- Midazolam - GABAA receptor agonist
- Butorphanol - K-agonist and either u-antagonist or weak u-agonist
Key Points
- All birds were sedated by 15 min, no difference in sedation score between high and low dose alfaxalone but duration of high dose was longer than low dose
- HR didn’t change from baseline and wasn’t different between high and lose dose
- RR was higher compared to baseline, no difference between high and low dose
- Cloacal temp decreased from baseline, no difference between high and low dose
- High dose had more muscle tremors/fasciculations than low dose
- Both low and high dose facilitated intubation and radiograph positioning right after sedation but high dose allowed positioning for longer (at later time points)
- Both groups retained response to toe pinch and feather pluck - this sedation protocol does not provide adequate analgesia
- No difference in vocalizations between high and low dose
- Full recovery of all birds (one died from cloacal rupture)
- One bird experienced respiratory distress that resolved with oxygen supplementation
- Birds lost weight throughout the study - possibly from being separated and handled
Conclusions
- Intranasal midazolam-butorphanol (2 mg/kg each) and IM alfaxalone (2 and 5 mg/kg) was a safe and effective method for sedation of Quaker parrots for intubation and radiographs
- Recommend 2 mg/kg to reduce muscle fasciculations, produced the same level of sedation as 5 mg/kg
- Provide oxygen, heat support, and analgesia if indicated
A recent study investigated the mu and kappa opioid receptor distribution in the budgerigar brain.
What is the scientific name of the budgerigar?
What was the predominant receptor in the budgerigar brain?
- What other species is this consistent with?
- How does this differ from day old chicks?
Qualitative investigation of µ-and κ-opioid receptor distribution in the brains of budgerigars (Melopsittacus undulatus)
Sojka PA, Smith SM, Greenacre CB, Newkirk K, Mountain DJ
Key Points:
- Historically, studies have supported the use of κ-agonist and µ-antagonist drugs, such as nalbuphine or butorphanol, for analgesia in psittacine species
- Fluorescent in situ hybridization (FISH) is an older technology that has seen a resurgence with the advent of highly sensitive and specific probes that can target mRNA, DNA, and proteins
– This study was facilitated by the publication of the budgerigar genome
– This information allowed for the development of highly sensitive and specific probes for µ- and κ-opioid receptor mRNA specific for this species
- This qualitative study supports the clinical impression that many psittacine birds have an analgesic response to κ-opioid receptor agonist and µ-opioid antagonist drugs
– The findings are most consistent with those observed in earlier pigeon studies:
– There is a higher relative predominance of κ- over µ-opioid receptors in the forebrain but no relative predominance in the midbrain
– Conversely, in the day-old chick forebrain and midbrain, µ-opioid receptors predominate over κ-opioid receptors
- The distribution of the δ-opioid receptor was not included in the scope of this study
– The function of the δ-opioid receptor in avian species is still unclear
– The δ-opioid receptor is widely expressed in the CNS & PNS and is usually found in different cell types than the µ-opioid receptor
– It may also be more efficacious in inflammatory, neuropathic, and chronic pain than µ-opioid receptors, which are more effective in acute pain
TLDR: Consistent with previous studies in pigeons and domestic chicks, κ-opioid receptors were more abundant than µ-opioid receptors
A recent study investigated the use of poloxamer P407 gel to administer butorphanol to orange-winged Amazon parrots.
What is the scientific name of the orange-winged amazon parrot?
What is polaxamer P407?
- How did it function in hispaniolan amazons when butorphanol was mixed with it?
- What did a previous pharmacodynamic study in OWAP show?
How was butorphanol absorbed with P407 in this study in OWAP?
- How did the authors attribute the mixed pharmacodynamics from the previous study?
Pharmacokinetics of butorphanol tartrate in a poloxamer P407 gel formulation administered to orange-winged Amazon parrots (Amazona amazonica).
American Journal of Veterinary Research. 2022;83(8):online
Background
- Butorphanol reduces minimum alveolar concentration of iso in cockatoos, grey parrots
- Terminal half life in Hispaniolan Amazon parrots was very short (½ hr at 5 mg/kg), RTHA 0.9 hr, GHOW 1.8hr
- Oral bioavailability in Hispaniolan Amazon parrots is poor (6%)
- Poloxamer 407 - hydrogel, liquid at room temp, becomes a gel at body temp after injection via micellar packing, allows for slow dissolution and sustained release of hydrophilic and hydrophobic drugs
- Hispaniolan amazon parrots given But-P407 8.3 mg/kg had plasma conc 2x higher SQ than IM and good absorption of 12.5 mg/kg SQ
- Orange-winged Amazon parrots had increased thermal withdrawal latency for IM but not SQ
Key Points
- Mean plasma conc in OW parrots were above therapeutic range in other spp. by ½ hr and stayed high at 4 hr, then dropped by 8 hr.
– 1 bird never achieved therapeutic concentrations for other species but did reach antinociceptive concentration for HA parrots in previous studies of torb.
- Similar Tmax as HA parrots but slightly lower Cmax, shorter terminal half life (about half)
- No explanation for lack of effect in previous PD study, torb appears to be well absorbed so maybe P407 is not an effective vehicle - causes alterations in lipid metabolism in rabbits and rodents so may alter lipid transport across the blood-brain-barrier reducing torb transport to target opioid receptors
Conclusions
- Absorption of butorphanol from a P407 25% base SQ in OW Amazon parrots followed a PK profile consistent with that of a sustained release drug.
- Plasma levels of 12.5 mg/kg SQ would be expected to provide antinociception for at least 4-8 hrs but this effect was not seen in a previous PD study in this species, while butorphanol tartrate in its standard form has been shown effective.
A recent study used carrageenan induced inflammation to study weight bearing, locomotion, and thermal antinociception in cockatiels.
What is the scientific name of the cockatiel?
What is carageenan? How was it used in this study?
How did treated birds change their weight loading?
- Was there differences in rotation perching?
- Any differences in thermal stimulus perching?
- How did treatment change footpad size?
AJVR 2022 83(8) online
Evaluation of weight-bearing, locomotion, thermal antinociception, and footpad size in a carrageenan-induced inflammatory model in the cockatiel (Nymphicus hollandicus)
Key Points:
- Carageenan is a sulfated mucopolysaccharide extracted from Irish moss, stimulates local inflammatory responses when injected into rodent tissues
– Has been used to study weight bearing and behavioral changes in rats with significant findings
– Wt bearing abilities have differed significantly between rats injected vs controls
– Reduction of thermal threshold tolerance
– Induction of footpad edema at injection site
- Weight loading: Treated birds had a significant decrease in weight loading on their treated foot at 143 hr and 167 hr compared to baseline, no difference over time in the control group
– Decrease in treated group vs control group at 120, 143 and 167 hr
- Rotational perching: No differences at any time point
- Thermal stimulus perch: No effect of treatment or time was seen
- Footpad imaging/ swelling grading: treatment increased vertical size and horizontal size of the footpad vs control
– Significant increase in footpad area from 47hr - 504 hr in treated group compared to control group
– Treated birds had footpads that remained significantly greater in size compared to footpad of control birds for the first 3 weeks after injection
- Footpad lesion significantly decreased weight bearing on that leg
Take home message:
- SC injection of carrageenan into the left footpad of cockatiels prompted the formation of inflammation and altered weight bearing of the affected limb
- Some showed wt bearing changes as early as 1.5 hr while others did not show differences until 96 hr, making prediction of peak effects difficult
- Assessment of weight-bearing load and footpad dimensions was sensitive and reliable assessments of inflammation and differentiating treatment from control cockatiels.
- In contrast, thermal threshold withdrawal and rotational perch locomotion were not found to significantly differ between groups, despite being reliable methods
A recent study investigated the pharmacokinetics of cannabidiol and cannabidiolic acid in orange-winged amazon parrots.
What are the functions of cannabinoid receptors?
Describe the levels of cannibinoids achieved in the plasma in this study?
- How did this differ from the study in hispaniolans?
Were any side effected noted?
Were there any significant biochemical changes after administration?
These birds were fasted - how could feeding at the time of administration alter absorption of these compounds?
AJVR 2023 84(4)
Twice-daily oral administration of a cannabidiol and cannabidiolic acid–rich hemp extract was well tolerated in orange-winged Amazon parrots (Amazona amazonica) and has a favorable pharmacokinetic profile
Intro
- Chronic pain management options needed in avian species
- The cannabinoid receptors CB1 and CB2 are involved in different physiological processes such as neuronal plasticity, pain, inflammation, and immune regulation among others
- In birds, CB1 receptor has been identified in chickens and budgerigars,
- In mammals, CBD is metabolized by the liver to its active metabolite 7-hydroxy-cannabidiol (7-OH-CBD)
- Objectives: determine the plasma concentrations and pharmacokinetic profile of 8 CBs following oral administration of a full spectrum hemp-extract (single and multi dose) and to evaluate safety parameters after multiple-dose administration
Results and discusssion
- One bird in the lowest dose pilot study had a single seizure. Birds in the highest dose group were markedly sedated but had no other adverse affects
- Single dose study (middle dose)–no adverse affects
- Multiple dose study–All birds maintained their body weight with less than 10% fluctuation, none of the birds had signs of appetite, sedation/agitation, or behavior changes, and none, except for 1 bird in the treatment group that developed intermittent diarrhea, had changes in urofeces as subjectively assessed.
- The predominant metabolite was 11-hydroxy-9-tetrahydrocannabinol.
- no significant effect of time or treatment on the lipid panel and on chlorides, bicarbonates, phosphorus, total calcium, ALP, GLDH, and uric acid
- Plasma glucose, potassium, and total proteins (TP) were significantly higher after treatment. None of the elevations were clinically significant
- The pharmacokinetic parameters of CBG, CBC, CBN, and the metabolites 7-COOH-CBD, COOH-THC, COOH-THCGlu, and 7-OH-CBD were not able to be determined because the plasma concentrations were below the limit of quantitation at most time points at the doses evaluated.
- twice daily administration of the evaluated hemp extract is well tolerated in healthy OWAP and results in plasma concentrations above 50 ng/ mL at a dose of hemp extract based on 30/32.5 mg/ kg of CBD/CBDA for at least 6 hours without significant adverse effects
- The birds in this study received hemp extract without food administration. CBD and THC are highly lipophilic substances;therefore, coadministration of a high-lipid meal could enhance their solubility and absorption
- Compare to study in hispaniolan amazons–very different results at higher doses
A recent study investigated the pharmacokinetics of cannabidiol in Hispaniolan amazon parrots.
What is the scientific name of the hispaniolan amazon parrot?
What were the serum half-lives like for cannabidiol for this species?
- How did that differ from orange-winged amazon parrots?
JAMS 2022 36(2):121-127
Pharmacokinetics of Cannabidiol in the Hispaniolan Amazon Parrot (Amazona ventralis)
Carpenter JW, Tully TN Jr, Rockwell K, KuKanich B
Background:
- Phytocannabinoids = chemicals from botanical sources that affect the endocannabinoid system
– Cannabinoid receptors are expressed in most animals
– THC = major psychoactive cannabinoid
– Cannabidiol (CBD) = major non-psychoactive cannabinoid
– CBD is not synthesized in the cannabis plant directly
– Instead synthesized during plant extraction from cannabidiolic acid (CBDA)
– CBD associated with anecdotal health benefits in humans & animals
Key Points:
- Prospective PK study (n = 12 Hispaniolan Amazon parrots)
– CBD solution = Canna Companion
– Pilot Study: 10 mg/kg & 20 mg/kg CBD PO -> serum half-life peaked at 2 hours
– Tolerability Study: no adverse clinical signs at 60 mg/kg & 120 mg/kg CBD PO
– Main PK Study: 60 mg/kg & 120 mg/kg CBD PO
- CBD formulation used had a short half-life, even at 60 mg/kg and 120 mg/kg
– Additionally, plasma concentrations achieved were extremely variable
- Plasma concentration variability may have been related to:
– Small sample size
– Interindividual pharmacokinetic differences
– Interindividual differences in first pass metabolism
– Amount of food in the crop at the time of dosing
TLDR: Oral CBD given to Hispaniolan parrots with empty crops failed to produce sustained plasma concentrations
A recent study investigated the success of dietary conversion methods to transition parrots from seed-based diets to pelleted diets.
What are some of the deficiencies that can occur with seed-based diets?
- What diseases are associated with seed based diets?
What were the three methods used for diet transition?
What was the success rate of transition?
- How quickly did this occur?
- What were signs that birds would not transition?
JAMS 2022 36(2) 145-152
An Evaluation of Three Diet Conversion Methods in Psittacine Birds Converting from Seed-Based Diets to Pelleted Diets
Cummings AM, Hess LR, Spielvogel CF, Kottwitz JJ. An Evaluation of Three Diet Conversion Methods in Psittacine Birds Converting from Seed-Based Diets to Pelleted Diets.
Key Points
- Seed based diets are highly palatable and cheap, contain excess fat, deficient in vitamin A, D, +/- E, K, B12, riboflavin, pantothenic acid, choline, niacin and major minerals - Ca, P, Na, Mn, Zn, Fe, Iodine, Se and imbalance in the amino acids lysine and methionine.
– Linked to egg binding/dystocia, NSHP, hypocalcemia seizures, renal disease, gout, skin and feather defects and FDB, ocular disease and immunodeficiencies.
– Excessive fat also results in metabolic diseases - cardiac dz, athero, hypercholesterolemia, hyperTGemia, fatty liver, lipoma, joint disease and pododermatitis
- New commercial pellet diets recommended as 75% of the diet
- This study was conducted at homes with owners, who selected 1 of 3 methods and asked to fill out a survey. Converted if pellets became 60% or more of the diet.
– Birdies Choice” was a reward-based method in which birds were offered 3 different pelleted diets on a tabletop. If there was a positive interaction and the bird ate one or more of the diets, the bird was rewarded. The preferred pellet was then gradually transitioned into their food dishes.
– In the “Slow and Steady” method, pellets were alternated with familiar food at varying intervals to increase the birds’ exposure to the pellets.
– The “Tough Love” method maximized exposure to new pellets by introducing a small portion of familiar food for a limited time, along with multiple dishes of new pellets.
- 83 client owned birds representing 24 species, all age classes and both sexes - 96% converted to the pellet diet regardless of the method used
– 90% converted in <30 days, median time to diet conversion was 5.5 days
– Diet conversion time did not differ between the different methods used. Sex, life stage, and taxonomic family did not impact diet conversion, either.
- In the minority that did not take to the pelleted diet, birds reacted by screaming/aggression, food tossed/dumped from bowls, or fear/rejection of the food
- No birds left the study because of health concerns. I.e. weight loss.
- The TL method resulted in 100% conversion in the shortest amt of time, likely bc it provided maximal exposure to the pellets in the birds favorite places in the enclosure. The other two methods required owner’s direct positive reinforcement of the bird’s interaction with the pellets.
Take home message
- 96% conversion rate indicates that parrots can convert from seed-based to pellet-based diets rapidly (i.e. within 1 month, and for most <1week) and successfully at home when the owners are committed to the process and understand the transition methods
A recent study investigated fluoroscopic angiography to evaluate cardiovascular structures in Hispaniolan amazon parrots.
What is the scientific name of the HIspaniolan amazon parrot?
What is teh most common vascular disease of birds?
How did contrast fluoroscopy perform in this study?
- Which view was best?
Journal of Avian Medicine and Surgery, 36(2): 178-186
Evaluation of a Fluoroscopic Angiography Protocol in Hispaniolan Amazon Parrots (Amazona ventralis)
Aller, Theresa L., Guzman, David Sanchez-Migallon, Stern, Joshua A., Douglas, Jamie M., Golsen, Bryce M., et al.
Key Points:
- Most common vascular disease in bird is atherosclerosis
– Radiography often first line to evaluate size, contour and opacity of the great vessels and cardiac silhouette
– Poor means for determining vascular disease
– Brachiocephalic trunks and descending aorta most commonly affected in atherosclerosis
– Radiographs are insensitive for diagnosis but often first line diagnosis. Transesophageal echo has improved resolution and ability to use M-mode over regular and contrast ultrasound from ventromedial and parasternal approaches
– Angiography can provide more complete vascular evaluation and reliable measurements not complicated by anatomy – useful for visualization of great vessels, measuring vascular diameter and eval of vessel lumens
- Angiograms could be reliably measured across observes with near perfect intraclass correlation coefficients for intraobserver variability and moderate ICC for interobserver variability
– Moderate interobserver variability and near perfect intraobserver variability in the measurements were obtained for the left brachiocephalic trunk, right brachiocephalic trunk, and descending aorta
– VD outperformed lateral measurements
- Visualization of cardiac vasculature was not as hindered by adjacent or overlapping soft tissue structures
Take-Home Message:
- Performing nonselective fluoroscopic angiography with patients under general anesthesia and administering 3 mL/kg of nonionic iodinated contrast medium intravenously at a constant rate of 1–2 mL/kg per second is a reliable technique with relatively consistent vascular measurements obtained.
- Protocols used in this project were considered safe for all the parrots involved and effective for the real-time evaluation of the contrast-enhanced chambers of the heart and lumen of the great vessels during the cardiac cycle.
A recent study investigated polaxamer 407 gel impregnated with carboplatin for treatment of squamous cell carcinoma in African grey parrots.
HOw does SCC present in avian species?
- Are there any risk factors?
- What is its behavior like?
How was this bird treated? How well did it work?
Treatment of Recurrent Multifocal Cutaneous Squamous Cell Carcinoma in an African Grey Parrot (Psittacus erithacus) with Intralesional Carboplatin in Poloxamer 407.
Adair JE, Riggs GL.
Journal of Avian Medicine and Surgery. 2022 Aug;36(2):200-5.
Key Points:
- SCC - commonly reported malignant avian neoplasia - typically irregular, ill-defined area of proliferative, often ulcerated tissue
– Some species predilections for locations on the body, commonly mucocutaneous junctions and oral cavity
- Risk factors considered same as humans: hypovitaminosis A, chronic inflammation (trauma, UV), and skin infections
- Not likely to met, often locally invasive, can be difficult to completely excise
Take Home:
- Intralesional carboplatin in poloxamer 407 combined with surgical debridement with CO2 laser resulted in long-term (>2yr) resolution of SCC, similar to complete excision
- No clinically relevant adverse side effects, outpatient procedure
A recent paper described idiopathic extramedullary hematopoiesis in a yellow-collared macaw.
What is EMH?
How was it treated in this case?
JAMS 2022 36(2):206-214
Pathogenic Idiopathic Extramedullary Hematopoiesis in a Yellow-Collared Macaw (Primolius auricollis)
Coutant T, Cococcetta C, Phouratsamay A, et al
Background:
- Extramedullary hematopoiesis (EMH) = development of blood cells outside the bone marrow
– Usually trilineage (erythropoiesis, myelopoiesis, and thrombopoiesis)
– However, 1-2 cell lines may predominate, depending on pathogenesis
– Two most frequent sites: liver and spleen
– Other sites include kidneys, lungs, peritoneal cavity, paraspinal region, and lymph nodes (in mammals)
– Generally considered an incidental finding, usually no serious clinical implications
- In human medicine, causes of EMH can be classified into 5 categories:
1. Bone marrow failure
2. Myelostimulation
3. Inflammatory process
4. Abnormal chemokine production
5. Hematopoietic neoplasm
Key Points:
- Case report describes the diagnosis of idiopathic EMH in a yellow-collared macaw
– In the present case, the erythroid lineage predominated
- Most prominent feature was the severity of the lesions (severe hepatomegaly and hepatopathy)
- Tentative treatment was performed using hydroxyurea
– Hydroxyurea inhibits DNA synthesis; used for polycythemia vera and leukemia
A recent study described medullary liposarcoma in a lovebird.
How did this bird present?
How was it managed?
What were the histologic features of this mass?
- What stain was used?
Journal of Avian Medicine and Surgery, 36(2) : 215-219
Liposarcoma of Probable Medullary Bone Origin in a Lovebird (Agapornis roseicollis)
Lofgren, Nicolle T., Malka, Shachar, Renna, Caitlin M., Banuelos, Rosa M., Dennison-Gibby, Sophie, et al.
Key Points:
- 15 yo female lovebird presented for reluctance to fly after falling from perch
- Cx: painful and swollen left elbow with subcutaneous mass
– CBC – mild anemia
– CT – pathologic fx of left humerus with abnormal soft tissue within the medullary cavity of the humerus fragments and periosteal reaction and lucent lesions of the cortices.
- Surgical amputation of left wing performed
– Histo – malignant round cell tumor in the medullary cavity of the humerus with minimal invasion into surrounding soft tissue. Oil red O stain for lipid confirmed liposarcoma.
A recent study established RI for cockatiel hematology and compared Natt-Herricks to Smear-Based Leukocyte estimated.
What is the predominant leukocyte of the cockatiel?
How did Natt-Herricks compare to blood smear estimation?
JAMS 2022;36(3):250-261
Hematologic Reference Intervals and Comparison of Natt-Herrick Technique and Smear-Based Leukocyte Estimation in Cockatiels (Nymphicus hollandicus)
Monopoli MR, Guzman DS, Kass PH, Kol A
Key Points
- WBC quantification in birds typically involves a hemocytometer + specific stains
– Two of the most common stains are the Phloxine B and Natt & Herrick solutions
– Phloxine B = semidirect, only stains granules of heterophils and eosinophils
– Total WBC count is measured mathematically from a manual differential
– Natt-Herrick technique (NHT) = direct, all leukocytes are stained
– Blood smear technique w/ Wright-Giemsa also an economic and efficient method
- Lymphocytes = predominant leukocyte, a trend recognized anecdotally among avian clinicians
– Contradicts previously published cockatiel RI, but consistent with other avian species
– Stress-induced heterophilia = common avian response to handling & confounding factor
TLDR: No significant difference between Natt-Herrick and blood smear techniques for WBC estimation in cockatiels; however, blood smear seems to be the more accessible, affordable, and rapid option
A recent paper described the medical and surgical management of phaeohyphomycosis in a kea.
What is the scientific name of the kea?
How did this animal present?
- What diagnostic findings were made?
- How was this animal treated?
Journal of Avian Medicine and Surgery 36 (2022) 295-301
MEDICAL AND SURGICAL MANAGEMENT OF PHAEOHYPHOMYCOSIS IN A KEA (NESTOR NOTABILIS)
Nick Kirk, DVM, Natalie Antinoff, DVM, Dipl ABVP (Avian), and M. Scott Echols, DVM, Dipl ABVP (Avian) – Reviewed by AJC
Key Points:
- 2.5 yo FI kea presented for acute onset of abnormal behavior (laying on sternum w/ head resting on ground, wings splayed; lethargic, tripping on perches/toys, disinterested in treats, running into walls)
– Lived in a public outdoor enclosure w/ indoor holding, examined yearly for CBC/CHEM & Chlamydia
– PE: QAR, stumbling gait, decreased grip strength bilaterally (LMN process)
– CBC leukocytosis, CHEM nsf
– Awake radiographs: 2.8 x 2.1 irregular soft tissue radiodense mass compressing abdominal & caudal thoracic air sacs
– CT: 2.3 x 2.7 x 2.6 cm soft tissue mass medial/dorsal to proventriculus & pressing on proventriculus; appeared to originate from L ovary; mass wall or capsule not differentiated from L cranial renal division
- Given Lupron injection 🡪 10 days later performed exploratory celiotomy 🡪 L lateral approach (also on voriconazole throughout)
– Multiple adhesions to dorsal, medial, & medial ventral surfaces of mass; able to bluntly dissect away from kidney & excise from proventriculus; small inactive ovary identified during surgery
– Cytology of mass – RBCs, abundant mixed WBCs, septated pigmented fungal hyphae
– Cultures from mass – all negative
– Histo – fungal granuloma, specifically phaeohyphomycosis
- Voriconazole discontinued after 6 month CT showed no signs of recurrence
A recent study described cerebellar hypoplasia in African grey parrot chicks.
What are some causes of secondary acquired cerebellar hypoplasia in avian species?
JAMS 2022 36(3):308-315
Cerebellar Hypoplasia in Two Juvenile African Grey Parrots (Psittacus erithacus)
Taggers A, Kelly-Bosma M, Mastakov A, Allavena R, Doneley RJT
Key Points:
- First report of cerebellar hypoplasia of African grey parrots
– Radiographs & lab work were unremarkable
– Necropsy findings were consistent w/ diagnosis
– Possible genetic sex-linked etiology, given the third unaffected clutch mate was male
– Hereditary sex-linked cerebellar hypoplasia found in light Sussex chickens
- Historically, cerebellar hypoplasia, abiotrophy, and dysplasia have been used interchangeably
– Modern histopathological diagnostic techniques have allowed enhanced differentiation
- In birds, secondary acquired cerebellar hypoplasia has been attributed to parvovirus, avian leukosis virus, Chlamydia psittaci, and cryptococcosis
A recent paper described multiple myeloma in a red-lored Amazon parrot.
How did this bird present?
- What changes were seen on CBC?
- What changes were seen on chmistry?
How was the diagnosis confirmed at necropsy?
Journal of Avian Medicine and Surgery, 2022: 36(3), 316-324.
Multiple myeloma with aberrant CD3 expression in a red-lored Amazon parrot (Amazona autumnalis).
Tovar-Lopez, G., Evans, S., Gutiérrez, J. F. M., Moore, A. R., & Sadar, M. J
Key Points:
- Multiple myeloma – rare lymphoproliferative disorder characterized by systemic proliferation of PCs that can result in excessive Ig secretion, approx. 1% of tumors in dogs and humans
– Diagnostic criteria – at least 10% clonal bone marrow plasma cells, presence of monoclonal gammopathy in serum or urine, and evidence of end organ damage or presence of >1 lesion
– Diagnosis in dogs requires presence of neoplastic cells in the BM + monoclonal proteins in serum or urine or osteolytic lesions
- 20 yr F red-lored Amazon presented for 2 wk of weakness. Toxic hets and reactive lymphs on
– CBC 2 weeks prior on annual exam. Biochem – mild hyperproteinemia (normal albumin, moderate hyperglobulinemia).
– PE findings – QAR, fluffed, mild dehydration, distended coelom, mild ataxia, minor hematochezia
– Imaging – bilateral renomegaly, hypoechoic thickening of the muscular layer of the ventriculus.
– CBC at referral center – anemia, eosinophilia, monocytosis, intermediate to large lymphs with nuclei 1-1.5x that of a heterophil; atypical lymphs were immunoreactive for CD3
– Chem – hyperphosphatemia, hyperproteinemia, analbuminemia (0 g/dl) and hyperglobulinemia (13.6).
– Monoclonal gammopathy on agarose gel plasma protein electrophoresis
– Multiple myeloma suspected based on lack of inflammatory leukogram, monocloncal gammopathy, and atypical circulating lymphoid cells.
- Euthanized
– Nx: no gross lesions
– BM samples revealed 17% plasma cells, 24% large immature cells with occ plasmacytoid features
A recent study sought to validate gel-permeation high-performance liquid chromotraphy for lipoprotein analysis of quaker parrots.
How did GP-HPLC compare against a benchtop analyzer?
- Which measurement was reliable?
- How is that recommended to be used clinically?
How did the high cholesterol diet affect the lipoproteins?
Why are most birds hypertriglyceridemic?
JAMS 2023;36(4):345-355
Comparison of Lipoprotein Analysis Using Gel-Permeation High-Performance Liquid Chromatography and a Biochemistry Analyzer in Normolipidemic and Dyslipidemic Quaker Parrots (Myiopsitta monachus)
Beaufrère H, Wood D
Key Points:
- Lipoprotein analysis compared between a bench-top biochemistry analyzer vs. GP-HPLC
– Acceptable agreement for HDL-C for normotriglyceridemic samples
– No method for LDL was found to be clinically equivalent to GP-HPLC
– Including direct biochemistry, Friedewald formula, and alternative formulas
– Hypertriglyceridemia associated with strong interference effects in lipoprotein analysis
- 0.3% cholesterol diet caused transient/severe hypercholesterolemia, increased all lipoproteins
– 20% fat diet had minimal effects on plasma lipids
- > 20% of samples that were hypertriglyceridemic
– Likely associated with either female vitellogenesis or postprandial hyperlipidemia
- Because HDL-C was reliable in this study in normotriglyceridemic plasma samples, calculating non–HDL-C to determine risk factors is the most practical, reliable, and straightforward method
– Non–HDL-C encompasses all atherogenic lipoproteins
– Non–HDL-C = Total cholesterol – HDL-C
- Total cholesterol/HDL-C ratio (i.e., atherogenic index) is widely used in humans
– May also be a better risk factor than simple LDL-C measurements
- Total cholesterol, non–HDL-C, & total cholesterol/HDL-C recommended for clinical psittacine patients for diagnosis & monitoring of dyslipidemias (assuming patient isn’t hypertriglyceridemic)
– Most hypertriglyceridemia in birds is postprandial or due to female reproductive status
– Obtaining fasted samples on nonreproductive birds is also recommended
A recent study evaluated PT and aPTT in whole and citrated blood from Hispaniolan amazon parrots.
Birds have low concentrations of what clotting factors?
- Avian coagulation studies therefore focus on which pathways of coagulation?
How did PT measurement perform?
How did aPTT measurement perform?
JAMS 2023 36(4) 356-361
Evaluation of Prothrombin Time and Activated Partial Thromboplastin Time in Native and Citrated Whole Blood in Hispaniolan Amazon Parrots (Amazona ventralis) With a Handheld Point-of-Care Analyzer
Key Points:
- For birds, factors XI and XII, in particular, are reported to be found in low concentrations
- Therefore, previous studies investigating avian coagulation have primarily focused on prothrombin time (PT), which measures the extrinsic and common pathways of coagulation and does not significantly assess the intrinsic pathway
- InSight qLabs point-of-care unit in HAP’s: Low reliability measuring PT, high reliability measuring aPTT (especially on whole blood) but clinical relevance unclear
A recent study investigated dexmedetomidine-midazolam for sedation in budgerigars.
What doses were used?
How long did it take for peak effect?
What physiologic effects were noted?
How well did the sedation do in terms of positioning for imaging?
Was resedation observed?
Evaluation of dexmedetomidine-midazolam sedation in budgerigars (Melopsittacus undulatus)
Lauren E. Mumm, DVM; Christoph Mans, Dr med vet, DACZM, DECZM
JAVMA | JULY 2022 | VOL 260 | NO. 10
Key Points:
- Alpha 2 receptor agonist – dexmedetomidine with sedative, analgesic and muscle relaxing effects
– Side effects – dose dependent respiratory depression, bradycardia, and arrhythmogenesis
- Aim- evaluate dexmed-midazolam (DM) at both high and low doses of dexmedetomidine
- Time to sedative effect did not differ between high (HD - 40 mcg/kg) and low dexmed (LD - 10 mcg/kg) group both with 3 mg/kg midaz
– All in HD group were sternal recumbent and 8/10 in LD. All retained withdrawal response
– Could position for rads in 7/10 in HD. More mild sedation in LD with 4/10 able to take rads
– Peak effect at 15 mins
– Better sedation than prev study with butor-midaz, more individuals could be positioned for rads.
– No adverse signs seen (versus hyperexcitability during sedation/recovery and transient arrhythmia with alfax in budgies)
- HR and RR decreased significantly over time – resolved after reversals given
- After reversals, all birds were standing < 5 min after reversals with no difference between HD or LD
– Majority of birds were eating < 1 hr later
– 60 min after reversal, most birds showed signs of resedation though considered not clinically relevant (mild ataxia and loss of visual response)
A recent study investigated environmental factors associated with exudative cloacitis in kakapo.
What is the scientific name of the kakapo?
What is seen with exudative cloacitis? Is the etiology known?
What environmental factor may be playing a role?
ENVIRONMENTAL FACTOR INVESTIGATION OF EXUDATIVE CLOACITIS IN KĀKĀPŌ (STRIGOPS HABROPTILUS) ON WHENUA HOU (CODFISH ISLAND), NEW ZEALAND.
Jayasinghe M, Vallee E, Bolwell C, Digby A, Roe W, Midwinter A, Gartrell B.
The Journal of Wildlife Diseases. 2022;58(4):769-781.
Key Points:
- Kakapo: critically endangered, nocturnal parrot endemic to New Zealand, breeding populations intensively managed on 3 predator-free offshore islands including regular supplemental feeding
- Exudative cloacitis first noticed in 2002, found only on Whenhua Hou
– Inflammation of the vent margin or cloaca, often ulcerated, covered in crusty exudate, debilitating, can lead to reduced fertility
– Underlying cause/factors are unknown
Conclusions:
- Exudative cloacitis in kakapo is geographically restricted to Whenhua Hou, is slowly progressive with sporadic cases varying per year.
- No age or sex predilection, no effect of climate
- Does not appear to be infectious
- Possible association with ammonia levels (ie. fecal/urate build up) and moisture content in roost sites but no true statistical evidence
A recent retrospective evaluated the common causes of mortality and morbidity in budgerigars housed in an outdoor aviary.
What was the most common cause of death?
What were the most common neoplasia’s identified?
What were the two most common infectious diseases noted?
What other conditions were commonly seen?
Wildmann, A. K., Cushing, A. C., Pfisterer, B. R., & Sula, M. J. M. (2022).
Retrospective review of morbidity and mortality in a population of captive budgerigars (melopsittacus undulates).
Journal of Zoo and Wildlife Medicine, 53(2), 433-441.
Key Points:
Neoplasia #1
- Carcinomas (35),
– 22/35 renal, mets in 4
– MC comorbidity - Macrorhabus, gout (visceral pericardial lesions MC)
– Proventricular location 2nd MC for carcinoma
- Sarcomas (11) - MC undifferentiated (4), splenic (3)
– Multicentric lymphoma (5)
- Benign neoplasms (33), MC reproductive - Sertoli cell
Infectious
- MO diagnosed in 56 cases, MC finding proventriculus at the isthmus of the proventriculus and ventriculus ; 5/7 proventricular adenocarcinomas involved MO
- Sarcocystis in 17 cases (7 coinfections with MO) - interstitial pneumonia MC lesion atypical biliary hyperplasia and EMH also seen
– Opportunistic bacterial infections in 14 cases
Metabolic
- Hepatic lipidosis MC, 19/26 cases had comorbidities - neoplasia MC
Trauma - 41 cases - head trauma MC
A recent study evaluated clinical diagnostics for proventricular nematodiasis in Lorikeets.
What is the proventricular nematode affecting lorikeets?
- What is its pathogenesis?
- How is it diagnosed?
- What is its intermediate host?
What diagnostic tests may be useful in an outbreak situation?
- What signs might you pick up on exam?
JZWM 2022 53(2) 461-469
EVALUATION OF CLINICAL DIAGNOSTICS FOR PROVENTRICULAR NEMATODIASIS DUE TO SYNHIMANTUS NASUTA IN LORIKEETS (TRICHOGLOSSUS SPP.)
Background:
- Synhimantus nasuta, formerly Dispharynx nasuta or Dispharynx spiralis, is an acuarioid spirurid nematode with a cosmopolitan distribution, and infection has been reported in multiple avian taxa
- Attachment of the nematode’s head within the lamina propria of the proventriculus causes significant inflammation, resulting in dilatation of the organ, thickening of its wall, focal ulcerations with mucosal hemorrhage, overproduction of mucus, and potentially mechanical obstruction of the lumen
- Although clinical signs generally are nonspecific, combined observations from physical examination and initial diagnostic investigation may raise the suspicion of proventricular nematodiasis in a living bird
- Hard to diagnose antemortem–shedding is intermittent and there is a long prepatent period so fecals can result in false negatives
- Intermediate host is the pill bug (Armadiliidiidae)
- In this case series, clinical investigations were pursued during an S. nasuta infection in a flock outbreak situation to better define possible presentations
Key Points:
- n=4 confirmed cases
- An increased PKR (proventriculus-keel ratio) was observed only in birds that were actively shedding ova and was the only parameter with a statistically significant difference between confirmed and suspected cases
- The two lorikeets with the highest scores were confirmed cases and were the only ones that presented with clinical signs of severe anemia (lethargy and a pale iris color) confirmed by a low PCV.
- The other two confirmed cases had similar scores to the suspected cases and their main clinical sign was weight loss
- Birds were treated with ivermectin and then topical selamectin
- Fecal occult blood was also seen on birds with confirmed infections?
