Avian Flashcards
Aspergillus infection
brooders pneumonia, mycotic pneumonia or pneumomycosis - Cull affected birds
Yellow to grey nodules or plaques in lungs, air sacs, trachea, plaques in peritoneal cavity, may have greenish surface.
Conjunctivitis/keratitis.
Brain lesions may be seen in some birds with nervous signs.
Avian Chlamydiosis
Liver necrosis with large, granular basophilic intracytoplasmic inclusions
Carrier commonly by birds
Zoonotic (most commonly from parrots)
Clinical signs: mucous from nostrils, dark green droppings, coughing, poor feeding, death
Avian encephalomyelitis
Picornavirus. Transmission is commonly vertical (transovarian) but can be lateral (fecal-oral) as the virus can survive in feces for several weeks. Many older animals remain carriers. Therefore, treating only the symptomatic animals is not an effective strategy. The best prevention strategy is to vaccinate breeder animals to prevent transmission to progeny and to provide them with maternal immunity during the susceptible period.
Avian tuberculosis
Rarely seen in commercial chickens. Signs develop late in infection with weight loss, lethargy, and lameness. Granulomatous nodules of varying sizes are commonly found in the liver, spleen, bone marrow, and intestine. Other tissues may also be involved. Caused by Mycobacterium avium var avium. Several strains or serovars can cause disease. Large number of acid-fast bacteria provide a tentative diagnosis.
Avibacterium paragallinarum
gram-negative, pleomorphic, microaerophilic rod. Clinical signs include respiratory disease. Clinical signs: nasal discharge, sneezing, and swelling of the face underneath the eyes. Older birds seem to be more susceptible. Diagnosis is based on isolating the organism or inoculation of a healthy bird and then evaluating the development of clinical signs. Swell of the face and wattle must be differentiated from fowl cholera, which is caused by Pasteurella multocida.
Avipoxvirus Infection
Causes scabbing skin lesions or diptheric lesions in the respiratory tract, septicemia
Bordetella avium
turkey coryza
Candidiasis
thrush or sour crop, can occur post treatment with penicillin or nystatin
Cheyletiella
mite “walking dandruff”
Chlamydophila psittaci
causes lethargy, respiratory, and GI signs
turkey (Ornithosis): nasal discharge, weight loss, inappetence, and death. PM: pneumonia, multifocal necrosis in the liver and spleen, and severe pericarditis. Histopathology: many basophilic intracytoplasmic inclusions in the affected organs.
Treatment: Doxycyline
Chondrodysplasia in Turkey
Choline deficiency; can occur in chicks as well as young turkeys, but turkeys have a particularly high choline requirement. Causes stunting, poor feathering, and short thick bowed legs.
Cnemidocoptes pilae
“scaly face/leg” can be treated with topical or oral ivermectin. Most common in birds that are immunocompromised, and beak deformity may be permanent oven after the mite is cleared
Coccidiosis
fecal-oral transmission
Protozoal gastrointestinal parasite
Clinical signs include mucus-like or bloody diarrhea, dehydration, anemia, listlessness, ruffled feathers, stunted growth, and death. Drop in egg production
Treat flock with Amprolium
Cryptococcus
organism with large capsule seen with India Ink
Systemic fungal disease, usually don’t show any clinical signs
Zoonotic - can be fatal in people
Dermanyssus gallinae
“red mite” ectopic parasite - treat environment, they are nocturnal feeders and severe infestations can cause anemia and decrease reproductive potential. Management depends on effective treatment of the environment with residual insecticides. Individual animals can be treated with a variety of topical agents but long term management depends on environmental control
Egg Drop Syndrome
atadenovirus-induced disease characterized by the production of pale, soft-shelled, and shell-less eggs by apparently healthy laying hens
Eimeria in turkey treatment
add amproline to water
Erysipelas
gram-positive, slender, pleomorphic rods in the liver
Treatment is rapid-acting penicillin simultaneously with erysipelas bacterin.
turkey’s dying suddenly after exhibiting ataxia and weakness. Diffuse darkening of the skin and enlarged and friable livers and spleens in affected animals. Gram-positive, slender, pleomorphic rods. Treat with Intramuscular sodium penicillin
Fowl Cholera
Caused by Pasteurella multocida, a Gram-negative, non-motile, pleomorphic rod. As with most poultry diseases, it is preferable to prevent introduction of the disease into a flock with biosecurity measure. If treatment is attempted, it should ideally be based on culture and sensitivity but sulfonamides, tetracyclines, or penicillin are most often used.
Diagnosis: Gram-negative bacteria in blood or tissue
Fowlpox virus
Pox virus - also known as avian pox, sore head, or avian diphtheria.
Intracytoplasmic inclusions
Relatively slow-spreading disease that can spread by contact or by mosquitoes that may harbor infective virus for greater than a month.
Dry firm - main sign is raised, whitish wart-like lesion of unfeathered areas (head, legs, vent, etc.). The lesions heal in about 2 weeks. Unthriftiness, decreased egg productiona dn retarded growth may be seen. Mortality is low with this form of the disease.
Wet form - mainly involves the oral cavity and upper respiratory tract. Lesions are diphtheritic and can ulcerate or erode mucous membranes. Marked respiratory involvement can lead to mortality.
A diagnosis is usually based on flock history and presence of these lesions. This is a pox virus and there is no specific effect treatment but there is a vaccine. Disease control is best accomplished by preventive vaccine as sanitation alone will not prevent spread of disease. Several vaccines are available and a single application results in permanent immunity.
Heterakis gallinarum
a nematode parasite that lives in the cecum of some galliform birds, particularly in ground feeders such as domestic chickens and turkeys. It causes infection that is mildly pathogenic. However, it often carries a protozoan parasite Histomonas meleagridis which causes of histomoniasis, blackhead disease
Histomonas meleagridis in turkey
Protozoan parasite; also called blackhead or infectious enterohepatic, is fatal to turkeys but less pathogenic to chickens. It causes extensive necrosis of the liver and cecum. For this reason, chickens and turkeys should not be housed together and turkeys should not be housed in areas where chickens were previously housed.
Infectious Coryza
bacterial disease that causes acute respiratory infection with nasal discharge, sneezing, and facial swelling; can effectively be treated with antibiotics
caused by Avibacterium paragallinarum in chickens
and Bordetella avium in turkeys
Infectious laryngotracheitis
Herpesvirus; acute infection which results in dyspnea, coughing, rales, and bloody tracheal discharge. Mortality is variable but can reach up to 50%.
Diagnosis: intranuclear inclusion bodies in tracheal epithelium or by isolation of the virus through tissue samples.
Treatment: Aimed at prevention and supportive care if cost effective. Vaccination is recommended
Knemidocoptes mutans
Mite - also know as scaly leg mite. White-grey debris forms between and on the surface of the scale resulting in the honeycomb crusts. The legs may become thickened and distorted. Diagnosis can usually be made by skin scraping or examination of the underside of a crust microscopically to detect the mite. The microscopic evaluation reveals two mites that look substantially different. These are the male and female Knemidocoptes mites. The adult female is almost round with short legs and devoid of suckers. The adult make is small with longer legs and suckers on long stalks. Treatment of choice is ivermectin.
Laminosioptes cysticola
Subcutaneous mite and typically causes 1-3 mm nodular subcutaneous lesions.
Liver parameters for avian species
Bile acids and AST most useful
Lymphoid leukosis
caused by an avian retroviruse
Chickens with lymphoid leukosis have few typical clinical signs. These may include inappetence, weakness, diarrhea, dehydration, and emaciation. Infected chickens become depressed before death. Palpation often reveals an enlarged bursa and sometimes an enlarged liver. Infected birds may not necessarily develop tumors, but they may lay fewer eggs.
Diffuse or nodular lymphoid tumors are common in the liver, spleen, and bursa -> findings will confirm disease, virus too widespread for isolation
What are the five types of clinical signs associated with Marek’s Disease? How do you prevent it?
Marek’s disease is a herpesvirus prevented by in-ovo vaccination. It is characterized by 1) thickened nerves (vagus, brachial, sciatic) 2) Paralysis of a leg, wing or the neck 3) Gray iris or irregular pupils 4) raised, rough skin around the feather follicles or 5) gray foci of neoplastic tissue in the liver, spleen, gonads, heart, kidney, lung, or muscle.
The final diagnosis is made by isolating the herpesvirus from lymphocytes obtained from the buffy coat.
Most common cause of liver damage in broiler chickens
Cholangiohepatitis from Clostridium perfringens infection. This is a common cause of ascites in this bird.
Mycobacterium avium var avium
causes Avian tuberculosis, granulomatous disease throughout the liver and GI tract.
Mycoplasma gallisepticum causes ____ in turkeys
causes severe sinusitis and air sacculitis in turkeys with much milder signs in chickens. Diagnosis is made by ELISA, rapid plate agglutination, or PCR. Secondary pathogens commonly play a role in this disease.
Newcastle Virus
Paramyxovirus
Causes signs that can range from respiratory, GI, or neurologic signs. Caused by hemagglutinating virus
Onset is rapid, and signs appear throughout the flock within 2–12 days (average 5) after aerosol exposure. Spread is slower if the fecal-oral route is the primary means of transmission, particularly for caged birds. Young birds are the most susceptible. Observed signs depend on whether the infecting virus has a predilection for respiratory, digestive, or nervous systems.
Mortality can be as high as 100%
can be isolated from oropharyngeal or cloacal swabs or tissues from infected birds by inoculation of the allantoic cavity
Vaccine available
Ornitharpsus sylviarn
Northern fowl mite and often infect the feathered regions around the vent. They spend the entire life cycle on the host. treat chicken
Ornithonysses bursae
Tropical fowl mite and often infect the feathered regions around the vent. They spend the entire life cycle on the host
Pacheco’s Disease
herpes virus, incubation period longer than most quarantine periods, inclusion bodies confirms diagnosis
acute viral hepatitis, primarily in parrots
Plasmodium relictum
Avian malaria: Intraerythrocytic parasite of birds. The nucleus of erythrocytes is often displaced tot eh periphery of the red blood cell in certain stages of the parasite’s life cycle. It most commonly affects passerines and is transmitted by mosquitoes. The gametocytes often contain a yellow-brown iron pigment. Many birds are asymptomatic, but the disease may cause hemolytic anemia.
Proventriculus
Glandular stomach
What dis
haemoproteus
