Sheep Pulmonary Adenomatosis

VIRUSES RETROVIRIDAE

Antigenicity

• The virus cannot be grown in culture, although it can be seen by EM on tumor cells of infected sheep

Pathogenesis

• Causes a proliferation of alveolar lining cells, producing massive amounts of fluid
• Proliferative foci project into alveoli and bronchi and from slow-growing tumors
• Death occurs between 3-4 years of age

Clinical signs:

• Low exercise tolerance
• Gradual weight loss
• Dyspnoea
• Coughing
• Nasal fluid discharges during wheelbarrow test
• Secondary bacterial infection by Pasteurella hemolytica often precipitates death
• PM reveals fawn-gray tumor (for more see here)

Epidemiology

• Found in 25% of pneumonia cases in Scotland
• Absent in USA, common in UK

Diagnosis

• Electron microscopy on lung biopsy

Control

• Cull clinically affected animals