Natural fatal Sarcocystis falcatula infections in free-ranging eagles in North America.

Three bald eagles (Haliaeetus leucocephalus) and 1 golden eagle (Aquila chrysaetos) were admitted to rehabilitation facilities with emaciation, lethargy, and an inability to fly. Intravascular schizonts and merozoites were present in 2 bald eagles, mainly in the lung tissue, whereas the third bald eagle and the golden eagle had lymphohistiocytic encephalitis with intralesional schizonts and merozoites. In all eagles, protozoal tissue cysts were present in skeletal musculature or heart.