Avian Flashcards
Avian blood
large, nucleated erythrocytes that live 20-35 days (less than mammals); Nucleated thrombocytes, heterophils instead of neutrophils
Why do birds feather pick?
Healthy birds groom themselves to reduce infestation. Sick birds don’t groom. Psittacines self mutilate d/t: skin irritants, boredom, dietary deficiency, psychosis, bacteria, virus, fungi; lack of sleep (lights on), contact with strange people, dogs and cats.
What do chewed feathers look like?
Ramus of feather is split longitudinally in an irregular, ragged fashion.
What is the cardinal sign of self mutilation?
Feathers on the head are normal (can’t reach there!)
Causes of enteritis:
Coccidiosis, giardiasis, psittacosis/chlamydiosis
Coccidiosis
Eimeria, isospora, dorseilla, Tyzzeria; Feces: blood tinged and watery, weight loss and chronic D. Tx: Sulfa drugs, amprollium in water
Cnemidocoptes
Cnemidocoptes pilae- MOST FREQUENT/IMPORTANT ectoparasite of small psitticines. Scaly faces and leg mite. Starts at angle of beak, spreads to other areas of head and body. Overgrown and disfigured beaks common- dermatitis. Dx: mites on skin scraping. Tx: Dichlorvos pest strips; liquid paraffin, petroleum jelly, mesulphan provide good penetration and dissolution of hyperkeratic tissue. Apply for 3 days, repeat in 1 week PRN. Topical tx alone NOT recommended- messy, bird may ingest!
Bird has a fracture- what do you do?
Radiographs; IV glucose (glycogen storage capacity lower in birds than other spp), coaptation splint (bind wing to body). Comminuted fractures likely.
What types of bones do birds have?
pneumatized and medullary
Sinusitis
See swelling just above and below the eye. Supraorbital and infraorbital sinuses. Started by Hypovitaminosis A
Egg binding: What is it? What causes it? Clinical signs? Treatment?
Common with cage and aviary birds. D/t obstruction or impaction of vagina with a fully formed egg. Atony or spasm of smooth muscle oviduct can occur. Caused by: obesity, oversized eggs, low blood Ca, poor muscle tone, nervousness, variation in temperature, lack of suitable nesting place. Signs: straining, nest-seeking, abnormal postures, paresis, when examined- egg palpable just above pelvic inlet.
Tx: Place in warm cage with infrared irradiation. Lubricating the cloacal opening, place the bird over steaming kettle not very effective. Manipulation can be overdone. If egg accessible in vagina- contents can be removed with hypodermic needle and syringe- remove eggshell fragments. Laparotomy if egg further up oviduct. Ca gluconate- IM- rapid expulsion of egg (may be associated with low Ca)
Beak deformities: birds affected, causes, treatment/prevention
Budgies- overgrown or distorted beaks
Caused by: trauma to the germinal layer, excesssive wear caused by climbing on metal cage, metabolic bone disease: overlying beak becomes distorted.
Tx: regular clipping with nail clippers, smooth with fine sandpaper.
Dislocation of jaw unlikely. Candidiasis can cause disfiguration and hyperplastic tissue growth
Persistent egg laying
cockatiels, remove oviduct (not ovary), Give budgies and psittacines medroxyprogesterone to treat
body thermoregulation
Hypothermia- anesthesia and sx
Hyperthermia- KETAMINE- postanesthetic hyperactivity
cloaca temperature is excellent indicator of high body temp. Treat with oxygen and IM dextrose and alcohol spray.
Giardia
protazoan, infection via contaminated feces- poor sanitation and hygiene. Budgies very susceptible. Chronic diarrhea, weight loss and occasionally death. SI may be filled with semisolid material, and contain large number of organisms. Foamy, foul smelling, yellow-brown diarrhea. Dx: Best method: intestinal scrapings of duodenal loop of freshly killed birds. Only cysts shed in droppings
Tx: Dimtridazole in water
Crop impaction
Caused by fibrous material that may be ingested by galliforms allowed to graze long grass, thread in cage, pigeons ingesting soft nesting material. Main sign: regurgitating movement, unproductive. Dx: palpation, Tx: vegetable/mineral oil, or surgery
Candidiasis:
Candida albicans- yeast- ubiquitous in nature- lives as commensals (normal flora) on the skin, mouth and alimentary tract of warm blooded animals and birds. Overgrowth causes disease. Occurs in young birds, cockatiels/lovebirds affected as adults. Prolonged ABX therapy predisposing factor. Signs: unthriftiness, crop stasis, weight loss, death, listlessness, NEUROTIC PSEUDOMEMBRANOUS PATCHES over mucosa of tongue, pharynx and crop. MUCOSA looks like TERRYCLOTH. Beak deformities. Dx: characteristic lesions or KOH. Crop wash cytology and culture. Gross lesions: crop thickening, raised while lesions on the GI mucosa, histopathology. Tx: nystatin, adequate vitamin A and B. Azole antifungals for systemic disease Tx: amphotericin B used for feather injection. Outbreak contributors: unsanitary housing, overcrowding, dirty utensils.
Air sacculitis
Air sacs- Thin walled extensions of the lungs that hold 80% of the volume capacity of the respiratory system. Prone to Aspergillus fungi and coliform bacteria infection. Present for some time, becomes fairly extensive before outward signs are evident. Tx air sacs with inhalation therapy- droplets must be <5um diameter.
Psittacine Beak and Feather Disease
Circovirus- non-enveloped virus. Occurs in wild Australian cockatoos- infects nearly all spp of Psittaciforms (parrot, cockatoo and NZ parrot). Abnormal molts and development of dystophic feathers beaks and claws of young psittacines. Feather dust from infected birds highly infectious. Necrosis of the bursa and thymus of young animals. African greys: panleukemia, Poicephalus spp. Lovebirds heavily affected. Transmission: horizontal (feces, feather dander, GI), and vertical Signs: acute overwhelming diseases with bilaterally symmetrical loss of all actively growing feathers over a few days. Chronic disease characterized by repeated replacement of feathers and qulls by deformed, twisted, dystrophic quills that fail to mature and are shed prematurely. Hyperkeratosis of feather shealth and outer layers of beak and claws. Dx: monocytes with intracytoplasmic inclusion bodies. Histopath, DNA PCR probe. NO RELIABLE TREATMENT!
Hypovitaminosis A
Need for growth, vision and epithelial maintenance. MOST COMMON nutritional disorder in practice. ALL birds with respiratory signs –> SUSPECT HYPOVITAMINOSIS A. All seed diets deficient in calcium, Vitamin A, amino acids. Sunflower seeds- high in fat, no nutritional value. Vit A: epithelial cell growth, maintenance. Deficiency causes squamous metaplasia of multiple epithelial surfaces. Transmission: individual or outbreak. Signs: small, white necrotic plaques in mouth and throat. Abscesses in mouth, swelling of supraorbital and infraorbital sinuses (above/below the eye). GI malabsorption, poor skin/feather quality. Dx/Tx: response to vitamin A. Patient history/Clin signs. Hyperkeratosis on biopsy. Serum/hepatic vitamin A levels. Tx: Supplement diet with Vitamin A on routine basis. Diet modification.
Cloacal prolapse
Caused by: egg removed surgically b/c of prolapse, weakened oviduct after normal egg laying. Persistent cloacal prolapse d/t a tumor (viral papilloma), cloacitis. Prolapse may contain intestine, oviduct, ureter, may lead to obstruction of these organs. Tx: Purse- string suture around the vent- place at cutaneous mucosal junction, or ureters may be trapped and serve supply permanently damaged. Two mattress sutures on either side of vent. Remove wedge of vent to reduce its circumference- male bird, dorsal aspect. Stainless steel sutures around vent to retain the cloaca. Cloacoplexy - suture abdominal wall to the cloaca, push the cloaca into position using cotton bud.
Psittacosis/ parrot fever
Chlamydia (rickettsia-like organisms). Chlamydophila psittaci intracellular. ZOONOTIC. Transmitted via aerosolization of feces. Signs: unthriftyness, lethargy, , upper respiratory infections, ocular and nasal discharge, enteritis, post mortem hepatomegaly (PATCHY FAINT NECROSIS), mottled enlarged spleen, air sacculitis, pericarditis, serosal hemorrhage. Long term debilitating disease. Dx: history, clinical signs, Chlamydial ab titers, biochem+/- elevated AST, impression smears from liver- ZIEHL NEELSEN stain. - pink intracytoplasmic inclusion bodies. Rads: hepatomegaly, splenomegaly, airsacculitis. Treatment: Tetracyclines are reported to be anti-vitamin B in activity. Oxytetracycline or chlorotetracycline for 45 days. Doxycycline- liquid suspension or medicated feed. Use feeders NOT lined with Fe, Cu, Zn b/c deactivates tetracycline. DO NOT PUT IN WATER!!! Requires 3x the concentration - makes water unpalatable.
Gout:
metabolic disorder: deposition of urates and uric acid crystals in different tissues or organs. Uric acid is normal product of nitrogen metabolism in liver and kidney. There are two forms, depending on side of deposition:
viseral urate deposition: impaired renal function, urinary tract obstruction. Articular: unknown etiology, high uric acid values
Clinical signs: light urate dusting on liver and pericardial surface- enlarged, swollen kidney. Lameness, reluctance to fly/perch, rigid/swollen/painful joints. Yellow centers around joints. Dx: visceral urate deposition at necorpsy, clinical signs for articular gout, murexide test of aspirated joint material–> purple red if positive.
Tx: symptomatic- incurable
ALLOPURINOL: inhibits zanthinoxidase and uric acid synthesis
glucocorticosteroids are contraindicated b/c of increased protein catabolism
Egg peritonitis
egglike material (fibrin) in abdominal cavity d/t ectopic ovulation Signs: sudden death, depression, abdominal distension, dyspnea, weight loss. adhesions. Tx: abdominal irrigation via laparotomy w/ abx Ova shed into abdominal cavity when birds handled/disturbed. Won't show congestion of peritoneal blood vessels- normal and sterile.
