Viral Enteritis in Juvenile Black-capped Chickadees Poecile atricapillus) in a Rehabilitation Setting_

摘要

A group of 31 juvenile black-capped chickadees (Poecile atricapillus) housed at a wildlife rehabilitation center all developed sudden lethargy followed by acute death. Prior to death, several birds demonstrated undigested food and one showed frank blood in their droppings. Necropsies on four of the birds revealed loss of body condition, dehydration, and evidence of enteritis including gas-distended intestines and the presence of yellow, watery fluid. Viral particles consistent with viruses of the family Reoviridae were seen when intestinal contents were examined by negative contrast electron microscopy. Reoviruses are common in mammalian hosts and also in domestic and wild avian species, but have not been identified in black-capped chickadees priorto this study. Reoviruses can be pathogenic or non-pathogenic in avian species, with 85-90% of the strains being non-pathogenic.1 The pathogenic strains have been associated with clinical signs of enteritis in ducks and pigeons,2 chickens,3 turkeys,4 grey parrots, and quail.5 Clinical signs also include arthritis and lameness in chickens6 and turkeys,7 respiratory infections in chickens,3 and neurological symptoms in a wild crow.8 Preliminary molecular analysis revealed that the reovirus recovered fromthe intestines of the chickadees was closely related to turkey enteric and arthritis reoviruses. Further studies should be conducted on identification and characterization of reoviruses in wild bird species.