avian pathology

Study Notes

Lesions: Multifocal to coalescing, well-demarcated, flat, irregularly round, red-beige areas bordered by a beige trim.
Clinical signs: Droopy wings, unkempt feathers, yellow droppings, high mortality rate, photophobia, inappetence, extreme thirst.
Pathogenesis/causes: Histomonas meleagridis spread by roundworm (Heterakis gallinarum), damage to smaller blood vessels.
Diagnosis: Post-mortem examination for typical lesions in the liver and caecae, histopathology, PCR.

Lesions: Multifocal to coalescing necroheamorrhagic hepatitis, multifocal, small, well-demarcated areas of hepatocellular degeneration and necrosis (loss of normal hepatic architecture), few large clear vacuoles displacing the nucleus (lipid degeneration).
Clinical signs: High mortality rate, photophobia, inappetence, extreme thirst, droopiness, ataxia, nasal discharge, soiled vents, diarrhoea
Pathogenesis/causes: Mardivirus anatidalpha 1.
Diagnosis: Postmortem examination, viral isolation, PCR testing.

Lesions: Warty growths, firm, grey-pitted nodules and plaques, proliferative dermatitis.
Clinical signs: Weakness, laboured breathing, emaciation, enlarged, deformed, swollen, painful joints, weight loss, increased thirst, ruffled feathers, lameness, dehydration.
Pathogenesis/causes: Avipoxvirus spread by biting insects, direct contact, and aerosols.
Diagnosis: Microscopic examination of biopsy, postmortem examination, PCR testing.

Lesions: Enlarged, deformed, swollen, painful joints.
Clinical signs: Weight loss, Increased thirst, ruffled feathers, lameness, dehydration
Pathogenesis/causes: Diet, genetics, environmental toxins, or infectious agents (IB).
Diagnosis: Postmortem examination, Microscopic examination

Lesions: Tumour of the ovary, oviduct or both, can metastasize; firm, solid, light beige tumors
Clinical signs: Abdominal discomfort, pelvic pain, urinary symptoms, appetite changes, nausea, cysts, diarrhoea, constipation
pathogenesis/causes: age, weight
Diagnosis: Post mortem

Lesions: Multifocal, firm pale tan nodules that diffusely affect the liver (due to a few diseases like Marek's disease)
Clinical Signs: Inappetence, weakness, diarrhoea, dehydration, emaciation
Pathogenesis/causes: Marek's disease, Reticuloendotheliosis virus.
Diagnosis: Histological examination, Pathological findings

Lesions: White to yellow nodules, multifocal and diffuse
Clinical signs: Coughing, lethargy, tail bobbing, gasping, cyanosis, sudden death, paralysis
Pathogenesis/causes: Fungal disease, incubation period 2-5 days.
Diagnosis: Lesions, pathological findings