Galliformes Flashcards
What are the 5 families in the order Galliformes? What species are in each of them?
- 5 Families:
- Phasianidae – Chicken, quail, partridges, pheasants, turkeys, peafowl, grouse.
- Odontophoridae – New World quails
- Numididae – Guineafowl
- Cracidae – Chachalacas and curassows
- Megapodiidae – Malleefowl, maleo, and brush-turkeys
Define the following poultry terms:
- Pullet
- Cockerel
- Cock, rooster
- Hen
- Pollar
- Broiler
- Roaster
- Chook
- Capon
- Alektrophobia
- Cochins and Brahmas
- Crest
- Frizzle feathers
- Saddle
- Shank
- Sex feather
- Sickles
- Snood
- Pickout or peckout
- Straight run
- Spent
- Fart egg, rooser egg, oops egg
- Pullet – Young female chick
- Cockerel – Young male chick
- Cock, rooster – Adult male
- Hen – Adult female
- Pollar – Genetic female with male phenotype
- Broiler – Meat chicken 5 lbs live weight at slaughter
- Roaster – Meat chicken 6-8 lbs live weight at slaughter.
- Chook – Australian term for chicken
- Capon – Castrated male
- Alektrophobia – Fear of chickens
- Cochins and Brahmas – Feather-legged breeds
- Crest – puff of feathers on heads of Houdan, Silkie, Polish breeds aka topkot.
- Frizzle feathers – Curl rather than lay flat.
- Saddle – part of back before tale.
- Shank – Tarsometatarsus
- Sex feather – Hackle, saddle, tail feather rounded in hen, pointed in rooster.
- Sickles – long, curved tail feathers of some roosters
- Snood – Turkey fleshy appendage behind nares.
- Pickout or peckout – Cannibalism at vent.
- Straight run – Clutch of newly hatched chicks that have not been sexed
- Spent – Hen that is no longer laying
- Fart egg, rooser egg, oops egg – small egg that passes through oviduct without reaching full size.
What is unique about the brain of the woodcock?
the cerebellum is ventral to the cerebrum and the foramen magnum is ventral to that
What is unique about the trachea of the Helmeted currasow?
It loops back to the cloaca before entering the lungs.
Describe the GI anatomy of galliform birds.
Describe the crop to ventriculus.
Do they have a gallbladder?
Do they have a cecum?
· GI
§ Distensible crop (except guana and chachalaca)
§ Muscular ventriculus
§ Well-developed ceca—all of them produce cecal droppings
§ Grit is not required for digestion
§ All species possess a gall bladder
· Feces – sulfur-colored droppings characteristic of histomoniasis. Cecal droppings are darker in consistency and occur at night.
What structures are unique to the galliform integumentary system?
· Integument
· Most species have spurs on their lower pelvic limbs
· Some species have portions of skin that is unfeathered, including the head, or ornamental structures
§ Snood = fleshy skin appendage near upper beak btwn the eyes
§ Prone to frost bite
· Since they are terrestrial, adaptation to be ground dwelling includes cryptically brown, black, gray—males may be brightly colored though
§ Not true of guineafowl, where both sexes are more drab colored
Describe the following musculoskeletal features in galliform birds?
How many cervical vertebrae do they have?
Is there any unique shoulder girdle anatomy?
What is their foot arrangement?
Are spurs attached to the bone?
· Musculoskeletal
· 16 cervical vertebrae
· Guineafowl have modified clavicles to hold elongated trachea
· Anisodactyl digits and commonly digit 4 is reduced in size
§ Phasianidae and Numidadae: digit 4 elevated, not in contact with the ground
§ Megapodiidae and Cracidae: digit 4 at same level as the ground
· Manus is shorter than, or about the same length, as antebrachium or brachium
· Sesamoid bone proximal to the carpus within the tendon of the tensor propatagialis muscle (see on rads)
· Spurs – composed of calcarial process ankylosed to the tarsometatarsus; removal is a surgical procedure.
Describe the reproductive anatomy & breeding strategy of Galliform birds.
· Reproduction:
· Functioning left ovary.
· Respiratory dz may predispose to oviductal impaction.
· Many exotic Galliformes are seasonal breeders, transition diet in early Feb.
· Guinea fowl form mating pairs, ratio of one male to 4-5 females recommended.
§ Eggs are tear-drop shaped (unique).
· Collect eggs once or twice daily depending on weather (more often if hotter).
· Infertile eggs can serve as source of bacterial growth (Pseudomonas) – remove from nest.
Describe the proper husbandry of galliform birds.
- Housing:
- Predator protection
- Heating of buildings not required
- Lack of adequate ventilation and retention of heat can result in resp disease.
- Ammonia will build without proper ventilation.
- Destroy cilia on trachea, allows for bacterial infection of lower resp tract.
- Fans and misters can reduce heat in hot climates.
- Additional heat can be provided by red heat lamps or heated floor mats for posthatch period, overheating and fire hazards are concern.
- Birds will crowd away from source if overheated.
- Sun exposure can cause feather color changes, result in disqualification for show.
- Loud noises can be frightening, cause piling in corners and suffocation.
- Heavy breeds can injure themselves jumping from perches.
- Small birds may get trapped in corners.
- Two next boxes for 3-5 hen flocks to reduce fighting.
- Individual housing units per species recommended rather than mixing.
What breed generalities would you discuss with a client looking to get backyard chickens?
- Choosing breeds:
- Commercial broilers not recommended for backyard flocks, will grow rapidly without restricted feed resulting in musculoskeletal and cardiac issues.
- Laying breeds tend to be lighter and more active.
- Meat breeds tend to be larger and calmer, less aggressive.
- Dual-purpose breeds are popular.
What are some common issues with hatching galliform chicks?
- Common problems with hatching chicks:
- Early deaths i.e. infertile eggs, improper storage prior to incubation, extreme temp fluctuation.
- Late deaths, not pipped i.e. extreme temp fluctuation and poor humidity.
- Pipped but dried and stuck to egg shell i.e. poor humidity in late incubation and hatching period, weakened embryos from temp fluctuations.
- Pipped but drowned in fluids or malpositioned i.e. turning malfunction during incubation.
- Once hatched, do not move until dry and fluffed.
- Chicks that hatch without full yolk sac absorption should be euthanized.
- Embryonated eggs euthanized by chilling.
- All chicken chicks should be vaccinated for Marek’s dz within 24h post hatch.
- Sex – when older, male chickens and turkeys have two dorsal papillae that can be observed after eversion of vent.
Speer
Describe the appropriate diet selection for chickens.
Describe the diets of the following galliform birds:
- Pheasants
- peacock pheasants and roul rouls
- Argus hens
- Koklass
- Blood pheasants
- Cracids
- Grouse
- Hoatzin
- Willow Ptarmigan
· Chickens:
o Starter, finisher, meat builder and laying/breeding rations.
o Laying birds must have Ca supplementation and layer ration.
o Scratch only as a supplement after regular feed has been consumed.
o Anticoccidials recommended for backyard flocks.
· Pheasant species similar to requirements for domestic turkeys: 28-30% protein as chicks, decrease to 20-24% as growing/breeding, then 13-15% for maintenance—can use commercial poultry or game bird pellets
· Produce, insects as supplements
· Precocious chicks, so pecking must be encouraged
· Peacock pheasants and roul rouls need high protein supplements like meat or eggs
· Argus hens feed chicks for their first few days of life (so hens won’t be eating at that time)
· Koklass = strict vegetarians
· Blood pheasants eat moss, lichen, ferns, grass and conifer needle buds
· Cracids (Currasows, Guan, Chachalaca) are generally frugivorous, but do eat some insects
o There is a commercial diet for currasows
· Tetraonidae (grouse) are generally herbivorous as adults and have large ceca, although the woodcock each 60% earthworms and 40% insects
· (Hoatzins have such specialized plant requirements (much of the diet consists of arum plant) – no suitable captive diet is known)
· Willow ptarmigan have been known to develop Vitamin C deficiency in captivity → source in wild is unknown
· Eared pheasants, monals and cheer pheasants use the upper bill to search in the soil for food
o If proper substrate for this digging is not provided, they may require bill trims
What stimulates chickens to molt?
- Molting:
- 3-4 month molt period normal for backyard flocks.
- Reduction of light period can stimulate molt. Important for hens to molt.
How can you tell if a given chicken is an active layer or not (assuming you haven’t seen which birds are laying the eggs)?
- Laying:
- Easiest way to determine lay is to palpate pubic bones, will have a 2-3 finger spread rather than meeting just below the vent as in nonlayer.
What is fipronil?
Is it legal to use in chickens?
Is it present in eggs?
What toxic effects have been documented?
- Fipronil
- broad-spectrum phenylpyrazole antiparasitic
- interferes with activation of insect-specific GABAA receptors, resulting in neuronal hyperexcitation and death in fleas and ticks
- can induce neurologic symptoms such as seizures, dizziness, sensory impairment, and agitation in humans by GABA receptor activity
- major metabolites, fipronil sulfone and fipronil desulfinyl, have less selectivity for insect receptors, compared with the parent drug
- repels insects from crops and homes
- not approved for use in food-producing animals
- no FDA approved fipronil products - pesticide regulated solely by EPA in US
- High residues in tissues – lipophilic drug
- long half life because of lipophilicity
- can exert toxic effects following inhalation or ingestion
- even fairly low concentrations of fipronil can cause mitochondrial injury by uncoupling phosphorylation, which can lead to cell death
- murine models - toxic to repro system, causes thyroid enlargement, cancer, hepatocyte damage leading to hepatomegaly and hepatocellular carcinoma
- dogs and mice - oral administration associated with neurologic damage, including developmental delays
- pesticide products for flea and tick prevention that are formulated for oral administration are regulated by the FDA, whereas topical pesticide formulations are regulated by EPA
- extralabel use of EPA-regulated products is expressly prohibited in the United States
- extralabel use of fipronil, including inadvertent administration, to poultry is unlawful in the United States
- FARAD may attempt to provide withdrawal interval recommendations in cases of accidental exposure or contamination
Consequences of fipronil exposure in egg-laying hens
JAVMA 2018 253(1) 57-60
How does lead affect backyard chickens?
Does lead move into eggs?
Are there any ways to reduce lead levels in backyard chickens?
Clinical signs:
· Lead toxicity in chickens - crop stasis to acute lethargy, diarrhea, ataxia, and marked weight loss, to more chronic progressive neurologic deficits due to axonal degeneration;
· symptomatic threshold for lead toxicosis in chickens, however, is not well established
o chickens may be relatively resistant to developing acute signs of lead toxicosis - early signs may be decrease in egg production
· BYCs would benefit from routine screening for lead
o presence of clinical signs are an unreliable indicator of exposure
· reduction in egg production is also documented in poultry that are intoxicated with lead
· chickens living in more densely populated areas had higher BLLs
· linear correlation between BLL of hens and the levels of lead in their eggs
· 1 study found that increased dietary calcium is correlated with lower liver and blood lead values
· 1 study found that supplementation with garlic reduces lead absorption
Subclinical Lead Exposure Among Backyard Chicken Flocks in Massachusetts
Daniel C. Mordarski, Jessica H. Leibler, Carolyn C. Talmadge, Gregory M. Wolfus, Mark A. Pokras, et. al.
Journal of Avian Medicine and Surgery, 32(3) : 185-193
A study investigated the effects of pathogens, parasites, and pesticide residues in Bavarian pheasants.
What did they conclude?
What pathogens were identified?
- Concluded that the health risk for human consumption of Bavarian game birds is low (no Salmonella or Campylobacter was found).
- Environmental toxins do not appear to be contributing to decline of game birds in Bavaria.
- An infectious agent only found in one bird – Mycobacterium avium avium/silvaticum.
- Some pheasants had tracheitis or bronchitis.
- Parasites – heterakis, capillaria, eimeria, teichostongylus, syngamus.
- E. coli most commonly cultured from liver, heart, lung. Considered normal contaminant.
- No Campylobacter was detected.
- Lead and promecarb toxicosis cause of death in two pheasants.
Schmitz, A., Kronthaler, F., Stein, K., Rinder, M., & Korbel, R. (2017). Decline of game birds (phasianus colchicus and perdix perdix) in bavaria: a survey on pathogenic bacteria, parasites, pesticide residues, and influence of set-aside land and maize cultivation. Journal of Zoo and Wildlife Medicine, 48(1), 18-30.
Describe an appropriate preventative medicine protocol for galliform birds.
· Biosecurity:
o Remove attractants for other birds or rodents.
o Remove carcasses immediately.
o Rodenticides and insecticides essential.
o Quarantine birds for 6 weeks. Three negative fecals at 2 week intervals.
· Quarantine
o For exotic Galliformes or domestic Galliformes destined for children’s zoo, minimum of 45-60 days
o Most diseases have 2 week incubation
o Serial testing for parasites—at least 3 negative fecals in a row, 2 weeks apart
§ Consider prophylactic treatment even if fecals are negative
· Perform exam
· Collect serum for Mycoplasma exposure, Newcastle disease, avian influenza
· Evaluate blood smears for hemoparasites
· Consider culturing feces for Salmonella while in quarantine
· Vaccination
Fowler 8
How long should galliformes be fasted for prior to anesthesia?
Four hours, to clear crop contents.
West
What complication can arise from intubation of currasows or guans?
- Convoluted tracheal anatomy of currasows and guans may cause problems if secretions increase in response to intubation or if bird aspirates
West
Describe the use of local anesthesia in chickens.
- Local Anesthesia
- Two main groups:
- Short acting – lidocaine and mepivacaine and long acting (bupivacaine)
- Intrathecal injection of local anesthetic for spinal cord blockade not possible not feasible due to large blood vessels.
- Birds are not more sensitive to side effects than mammals
- Broiler chickens: lidocaine 6mg/kg IV – no adverse effects
- Pharmacokinetics of lidocaine shown in chicken to be similar to mammals
- Author (Darryl Heard) uses 10mg/kg for lidocaine and mepivacaine as upper limit and 2mg/kg or less for bupivacaine.
West
Describe the appropriate use of propofol in chickens.
What complications are common?
What is the safety margin like?
- Propofol
-
Chickens: 4.5-9.7mg/kg followed by CRI 0.5-1.5mg/kg/min for 20 minutes, rapid induction – sometimes marked cardiopulmonary depression. – Single or multiple runs of premature ventricular complexes was observed in many birds. – one required lidocaine 0.5mg/kg IV for ventricular tachycardia.
- Prop at 3 times the induction dosage was fatal in all birds
- VERY narrow safety margin
- Prop at 3 times the induction dosage was fatal in all birds
WEst
Describe the use of alfaxalone in chickens. What doses are appropriate?
- Alfaxalone
-
[JEPM 29(2019) pp119-122] Induction of anesthesia with intravenous alfaxalone in 2 chickens.
- Poor quality at 5mg/Kg with period of excitement.
- Relaxation occurred after 10mg/Kg and 15mg/Kg total dose
- Individual variations including possible intrinsic differences in drug metabolism or differences in physiological status at time of surgery, and speed of administration of medication
-
[JEPM 29(2019) pp119-122] Induction of anesthesia with intravenous alfaxalone in 2 chickens.
What premeds have been shown to reduce MAC in chickens?
Morphine and methadone - West
What muscle relaxants have been used in chicken anesthesia?
- Muscle Relaxants
- Nondepolarizing short-acting muscle relaxant atracurium besylate (0.15 to 0.45mg/kg IV) can be used as an adjunct to inhalation anesthesia.
- Chicken: 0.25mg/kg – 95% twitch depression in 50% of birds – lasts 35 minutes
- 0.45mg/kg – 95% twitch depression in 95% of birds – lasts 50 minutes
- Cardiopulmonary effects not significant
- Chicken: 0.25mg/kg – 95% twitch depression in 50% of birds – lasts 35 minutes
West
What is the predominant opioid receptor in the chicken midbrain and forebrain
- opioid receptors
- endogenous opioid system functions in central processing of nociceptive information, with endogenous opioids (b-endorphin and enkephalin) binding to opioid receptors to inhibit pain
- chicken forebrain and midbrain - mu receptors most prevalent, detectable in chick embryos at 10 days old
- endogenous opioid system functions in central processing of nociceptive information, with endogenous opioids (b-endorphin and enkephalin) binding to opioid receptors to inhibit pain
West
Describe the use of morphine in chickens.
- Morphine
- Mu- agonist
- studies in chickens have been conflicting on effects and required dosage, and may be breed/strain-dependent
- Adult chickens 🡪 MAC-sparing effect
- Pharmacokinetics in chickens: 2 mg/kg IV
- Conflicting effects, dependent on breeds, clear faster than people or cats.
West
Describe the use of transdermal fentanyl patches in chickens.
- Transdermal patch in chickens. Delaski et al. JAMS 1(1):6–15, 2017 (see abstract below)
- Although maximum plasma fentanyl concentrations varied substantially by individual birds
- mean of elimination half-life was 7.2 +/- 3.7 hours = less variation
- In chickens, mu, kappa and delta receptors have been identified in the brains of chicks. Both mu and kappa agonists have reduced minimum alveolar concentration (MAC) in adult chickens
- Morphine leads to more sedation in chickens than butorphanol does
- Fentanyl reduced MAC in RTHA and HAP CRI
- Patches tend to have variability in absorption due to fur (epilated vs clipped, thickness of skin, skin permeability and drug clearance)
- Variability vs mammals may be due to increased metabolic rate, higher temperature, feathered skin.
- Mean maximum concentration was 2.86ng/ml.
- Elimination half-life was 7.2 h (in dogs it is 2 and in goats it is 5h)
- Cockatoos 0.02mg/Kg had Cmax of 3.33ng/mL but no effects on analgesia
- RTHA Cmax of 8.5-30ng.ml = reduced MAC
- This study did not reach those levels to decrease MAC, unclear if it would.
- Fentanyl patches 🡪 absorbed into skin acting as reservoir, absorbed slowly by first-order processs.
Describe the pharmacokinetics of meloxicam in chickens and its effect on eggs.
- Chickens: (Souza et al. JAMS 32(1):8–12, 2018 see articles)
- 1 mg/kg, chickens maintained a plasma concentration associated with analgesia in people for approximately 12 hours (0.5–1.5 ug/mL)
- No residues detected in eggs at 8 days (yolks) and 3 days (whites) = 2 week withdrawal is enough
- (Other studies: 5mg/Kg IM once = antinociceptive; 0.5-4mg/Kg = subjectively worked)
-
Pharmacokinetics and egg residues after oral administration of a single dose of meloxicam in domestic chickens (Gallus domesticus). JAMS 2017 31(4) 393
- 1mg/Kg PO once.
- drug was not detected after 4 days in egg whites and after 8 days in egg yolks
- 1 mg/kg PO in chickens appears to maintain plasma concentrations equivalent to those reported to be therapeutic for humans for 12 hours.
There are several management related illness in managed chickens.
Describe the presentations and management of the following conditions:
- Cannibalism
- Bumblefoot
- Fatty Liver
- Caged Layer Fatigue
- Cloacal Prolapse
- Egg Binding & Dystocia
- Cannibalism:
- Chicks – unusual, usually due to not enough feed or diarrhea/soiled vents that attract pecking.
- Control in older birds – reduce lighting, reduce number of birds, increase number of feeders, trim the beaks.
- Spray superficial wounds with pruning tar for topical treatment and ID of which individuals are pecking. Red spectacles or contact lenses reduces the behavior in peckers.
- Bumblefoot:
- Soaking in Epsom salts twice daily for 10 minutes can help remove scabs.
- Oral antibiotics may be warranted in infection. Prognosis declines with osteomyelitis.
- Soaking in Epsom salts twice daily for 10 minutes can help remove scabs.
- Fatty liver [hemorrhagic liver syndrome]:
- Extreme fat deposition, sudden drop in egg production, increased mortality.
- Obese, pale combs and wattles, may be covered with dandruff.
- Pets fed table scraps at risk. Mortality is from liver rupture and hemorrhage. Tx with prevention.
- Caged layer fatigue (Osteoporosis):
- Unable to stand, pathologic fractures, paralysis. Usually BAR.
- Probably caused by vit D3, Ca, P deficiencies and/or imbalances.
- May die acutely from spinal fracture, severed cords or recover following placement with easy access to food and water.
- IM vit D3 or IV Ca may help.
- Oyster shell added to diet ad lib for prevention. Needs to be retained in gizzard, don’t grind too fine.
- Increased Ca in diet for too long can result in urolithiasis or permanent cessation of parathyroid gland activity.
- Unable to stand, pathologic fractures, paralysis. Usually BAR.
- Cloacal prolapse:
- Stopping lay with reduced feed and decreased lighting, keeping vent clean in mild cases may help.
- Chicks hatched in fall with increase of light in early spring can be prematurely induced into lay and they are predisposed to prolapse.
- Controlling light extremely important.
- Egg binding and dystocia:
- Pullets too early in production or obese hens.
- Eggs can be refluxed into the coelom, single or multiple in oviduct, or shell membranes/concretions in oviduct.
- May be secondary to other reproductive disease.
- Yolk coelomitis may occur.
- Some salpingohysterectomized females can take on male characteristics (pollards).
Describe appropriate biosecurity for chicken operations.
- Biosecurity:
- Remove attractants for other birds or rodents.
- Remove carcasses immediately.
- Rodenticides and insecticides essential.
- Quarantine birds for 6 weeks.
Describe the lesions seen in calcium or vitamind D deficient chickens at necropsy.
- Ca/vit D deficiencies – rickets, osteomalacia.
- Rickets – juveniles, enlargement or beading of the junctions of the ribs with sternum and vertebrae (rachitic rosary), bending of ribs with lateral flattening of thorax, pathologic fractures, lateral deviation of sternum and spinal deformities.
- Histo – thickened zone of proliferation in growth plate of bones and enlarged parathyroid glands.
- Phorphorus deficiency or calcium excess results in these changes in absence of parathyroid gland enlargement.
- Histo – thickened zone of proliferation in growth plate of bones and enlarged parathyroid glands.
- Rickets – juveniles, enlargement or beading of the junctions of the ribs with sternum and vertebrae (rachitic rosary), bending of ribs with lateral flattening of thorax, pathologic fractures, lateral deviation of sternum and spinal deformities.
Terio
Describe the lesions associated with vitamin E deficiency in gallinaceous birds.
What age is most commonly affected?
- Vit E deficiency – accumulation of peroxides and deficiency in antioxidants results in encephalomalacia, muscular dystrophy, exudative diathesis.
- Encephalomalacia aka crazy chick disease.
- 2-4 week old birds, damage to capillary walls result in edema, hemorrhage, malacia.
- Swelling of cerebellum, petechial hemorrhage produces cherry red appearance.
- Necrosis of cerebellar folia.
- Muscular dystrophy – white streaks in muscle fibers. Can tx with addition of cysteine to feed.
- Exudative diathesis – subcutaneous edema, hemorrhage, green-blue gelatinous appearance in ventral thorax and abdomen, periorbital. Add selenium to feed. Individual birds, vit E injection.
- Encephalomalacia aka crazy chick disease.
What vitamin is deficient in chickens with curled-toe paralysis?
What other lesions may be present on necropsy?
- Curled-toe paralysis – vit B2 deficiency (riboflavin), required for myelin synthesis in peripheral nerves.
- Generalized demyelinating polyneuropathy.
- Sciatic, brachial, cervical, lumbar, large intramuscular nerves commonly swollen and soft.
- Sciatic may be 5x larger than normal.
Terio
What lesions are observed in chickens with vitamin A deficiencies?
- Hypovitaminosis A – Epithelial metaplasia and hyperkeratosis.
- Thickening of mucosa of tongue, choana, salivary glands, esophageal glands, formation of pustule-like nodules due to hyperkeratosis and distension of ducts with cellular debris.
- Conjunctiva, bursa of Fab, nasal passages, sinuses may have caseous exudate.
Terio
What nutritional deficiencies can lead to perosis?
- Choline or manganese deficiency – perosis or chondrodystrophy.
- Impaired endochondral bone growth.
- Small for age.
- Thickened, bent, twisted tarsometatarsi, deformed articular cartilage.
- Gastroc tendon dislocation may occur.
Terio
What foods may predispose chickens to goiter?
- Thyroid hyperplasia (goiter) – Dietary deficiency or excess of iodine, consumption of goitrogenic substances (spinach, cassava, peanuts, soybeans, kale, broccoli, brussels sprouts, cabbage, canola, cauliflower, mustard greens, radishes, rapeseed), goitrogenic drugs i.e. sulfonamides, and defective negative feedback control by the pituitary.
Terio
Describe the differences between acute and chronic gout in gallinaceous birds.
- Gout
- Urate accumulation in soft tissues or joints.
- Uric acid end-product of protein and purine metabolism (uricotelic).
- Acute (visceral) and chronic (articular) forms.
- Urate deposition in joints can occur in both forms.
- Acute urate deposition vs chronic urate deposition more appropriate terms vs visceral and articular gout.
- Granulomatous inflammation observed in chronic cases.
- Acute (visceral) and chronic (articular) forms.
- Uric acid end-product of protein and purine metabolism (uricotelic).
- Urate accumulation in soft tissues or joints.
Terio
In gallinaceous birds, exertional myopathy lesions are present in what muscles?
Broiler chickens are predisposed to what muscle lesions?
- Exertional myopathy commonly affects wings and legs.
- Deep pectoral myopathy – exertional compartment syndrome of the supracoracoid muscle characterized by ischemic necrosis in the absence of other muscular lesions.
- Compartmental myopathy produces high levels of lactic acid and myonecrosis.
- Complications include lactic acidosis, renal failure, arrhythmias, death.
- Compartmental myopathy produces high levels of lactic acid and myonecrosis.
Muscle turns green, dry, friable, necrotic.
Terio
Toxicities in chickens occur commonly from their pecking feeding behavior.
What are two of the most common toxicity types? What clinical signs would be seen?
- Heavy metals.
- Lead, zinc.
- CS – wt loss, lethargy, depression, anemia, paralysis, head tremors, convulsions, death.
- Demyelination of peripheral nerves, focal areas of vascular damage in cerebellum.
- Differentiate from botulism.
- Primary tx is removal of toxic metal.
- Lead, zinc.
- Mycotoxicosis.
- Aflatoxins, fusariotoxin.
- High risk of exposure due to consumption of primary seed-based diets.
- Cause immunosuppression, anemia, hemorrhage, hepatic degeneration, paralysis.
- Fusariotoxins assoc with feed refusal, extensive necrosis of oral mucosa and skin, hyperplastic bone marrow.
Terio
Amyloidosis in gallinaceous birds is commonly associated with what chronic infections?
- Amyloidosis.
- In chickens, turkeys – commonly associated with chronic infections i.e. Mycobacterium avium, Mycoplasma spp, Enterococcus faecalis.
Teiro
What are the most commonly seen neoplastic lesions in chickens?
- Neoplastic
- Virus-associated most commonly observed.
- Others – oral SCC, fibromas, lipomas, fibrosarcomas, leiomyomas in the mesosalpinx, leiomyosarcomas, rhabdomyomas, rhabdosarcomas, ovarian or oviductal adenocarcinomas with or without mets.
- Xanthomas – nonneoplastic, white to yellow nodular masses that occur in skin, SQ, and internal organs.
Terio
Quail bronchitis is caused by what virus?
What clinical signs are present?
What gross and histologic lesions would be present on necropsy?
- Adenoviruses – Aviadenoviruses
- Quail bronchitis Virus
- Resp dz, bobwhite and Japanese quail, < 4 wks age.
- Older birds subclinical.
- Gross – catarrhal tracheitis, corneal clouding, conjunctivitis, congestion in nasal passages and infraorbital sinuses.
- Lymphoplasmacytic tracheitis, bronchitis, necrosis, large intranuclear inclusions (basophilic).
- Quail bronchitis Virus
Inclusion Body Hepatitis in galliforms is caused by what virus?
What species are affected? Any age groups predisposed?
What other viruses may predispose them to IBH?
What lesions would be present on necropsy?
- Adenoviruses – Aviadenoviruses
- Inclusion body hepatitis – chickens, guinea fowl, turkeys.
- Immunosuppressive viruses i.e. chicken anemia virus or infectious bursal dz virus may predispose.
- 2-3 wk old birds or younger.
- Gross – Enlarged, friable, pale liver, necrosis and hemorrhage.
- Hydropericardium, hemorrhagic kidneys, intranuclear inclusions in hepatocytes and pancreas.
- Dx – hepatocellular inclusions within lesions, virus isolation, immunofluorescence, PCR.
- Inclusion body hepatitis – chickens, guinea fowl, turkeys.
Terio
Hemorrhagic enteritis is caused by what virus in gallinaceous birds?
What lesions may be present on necropsy?
- Hemorrhagic enteritis – Siadenovirus in turkeys, guinea fowl, partridges.
- SI hemorrhage, friable enlarged spleen with reticuloendothelial cell hyperplasia.
- Basophilic/amphophilic IN inclusions in RE cells.
- Marble spleen dz – Siadenovirus in pheasants.
- Spleen swollen, mottled, lungs congested and edematous.
- IN inclusions in MP and lymphocytes and Kupffer cells in liver.
- AGID or PCR can confirm.
- Histo – variable degrees of lymphoid necrosis in bursa.
- Lymphoid depletion in spleen, cecal tonsils, bone marrow.
- IN and IC basophilic globular or characteristic botryoid inclusion bodies in MP and epithelial cells of bura.
- May also be in thymus, spleen, cecal tonils, lungs, duodenum.
- Nonenveloped, icosahedral viral particles loosely arranged or in paracrystalline array.
- Dx – PCR (feces, tissues), ELISA, inclusion bodies in bursa and/or other organs.
Terio
Infectious Laryngotracheitis is caused by what etiologic agent in gallinaceous birds?
What species are primarily affected?
What lesions are present on necropsy?
- Infectious laryngotracheitis ILT – Gallid herpesvirus 1 (GaHV1).
- OIE reportable disease.
- Primarily chickens, also pheasants, peafowl, turkeys.
- Infects resp tract and conjunctiva.
- Latency in trigeminal ganglia, reactivated in immunosuppressed birds.
- Excess mucus, hyperemic mucosa, petechiae, intraluminal fibrinonecrotic material or hemorrhage.
- May occlude laryngeal opening, cause suffocation.
- Eosinophilic, IN inclusion bodies.
- Syncytial cells may be present.
- Dx – pathologic changes, VI, immunofluorescence, PCR.
Marek’s Disease is caused by what etiologic agent?
What species and age roups are typically affected?
How is this diseases transmitted?
- Marek’s disease virus – Gallid herpesvirus 2 (GaHV2).
- Quails, pheasants, turkeys, chickens.
- Unvaccinated immature chickens 2-7 mos old, or any age.
- Replicates in feather follicular epithelium, shed in dander.
Terio
Describe the four phases of pathogenesis in Marek’s Disease.
- Marek’s disease virus – Gallid herpesvirus 2 (GaHV2).
- Pathogenesis has four phases:
- Early – inhalation of virus with feather dander infects resp epithelial cell and local MP followed by viremia with cytolytic viral replication in lymphocytes.
- Latency phase in CD4+ T cells, systemic viral dissemination.
- Cutaneous viral infection, replication, shedding.
- Third – Reactivation in CD4+ T cells, late cytolytic stage and immunosuppression.
- Final – reactivation of virus, neoplastic transformation of CD4+ T cells.
- Pathogenesis has four phases:
Terio
Describe the lesions associated with Marek’s Disease.
- Marek’s disease virus – Gallid herpesvirus 2 (GaHV2).
- Gross – bursal and thymic atrophy, tumor infiltration and enlargement of peripheral nerves, white discoloration of iris with dyscoria, nodular lesions in feather follicles, hepatosplenomegaly, pale white tumors in various organs.
- Birds with visceral tumors may only be cachexic.
- Enlarged crop may be present from paralysis of the vagus nerve. Ddx for crop impaction.
- Peripheral nerve lesions – unilateral or bilateral, involve sciatic, brachial and vagus nerves and spinal root ganglia.
- Type A and B lesions present in peripheral nerves, characterized by infiltration of neoplastic CD4+ T cells and mixed inflammation with edema, respectively.
- PN lesions rare in quail and turkeys.
- Histo – Cerebral perivascular lymphocytic cuffing, vasculitis, edema, gliosis, lymphocytic meningitis. Neoplastic and pleomorphic T lymphs in visceral organs.
- Skin lesions surround feather follicles.
- Eosinophilic IN inclusions may be present within feather follicle epidermis.
- Lymphoma may be present in uvea, PN, brain.
- Gross – bursal and thymic atrophy, tumor infiltration and enlargement of peripheral nerves, white discoloration of iris with dyscoria, nodular lesions in feather follicles, hepatosplenomegaly, pale white tumors in various organs.
Terio
