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.
Which herpesvirus is associated with Pacheco’s dz?
Which herpesvirus causes mucosal papillomas in Gray parrots only?
Which herpesvirus causes respiratory dz?
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 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 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?
