Aspergillus in birds causes what lesion?

• A. Hemorrhagic ulcers
• B. Necrotic or white nodules
• C. Fibrosis of air sacs
• D. Granulomatous liver lesions

Answer: (B)

The key idea is that aspergillosis in birds commonly produces focal necrotizing lesions in the respiratory tract, especially white nodules in the air sacs and lungs. Inhaled Aspergillus spores germinate and form caseous, pale or white nodules that can coalesce and impair respiration. This makes necrotic or white nodules the best description of the typical lesion. While chronic disease can lead to broader inflammatory changes, granulomatous lesions in the liver or fibrotic changes in the air sacs are not the classic hallmark of aspergillosis in birds, and hemorrhagic ulcers aren’t the characteristic finding in this infection.