What serious health issue is caused by fungal growth in a bird's respiratory system?

Aspergillosis is a serious health issue caused by the fungal growth of Aspergillus species in a bird's respiratory system. This fungal infection primarily affects the lungs and air sacs, leading to respiratory distress, tissue damage, and can be life-threatening if not diagnosed and treated promptly. Birds are especially vulnerable to this condition when they are exposed to moldy food or bedding, or in environments that are damp and poorly ventilated.

In contrast, coccidiosis is a parasitic infection that primarily affects the intestinal tract, bumblefoot refers to a bacterial infection that causes sores on a bird's feet, and avian influenza is a viral infection that can affect a bird's respiratory system but is not caused by fungal growth. Each of these conditions has distinct causes and symptoms that differ fundamentally from those of aspergillosis, which is specifically linked to fungal growth in the respiratory system.