Submitted to: International Seminar on Poultry Production and Pathology Proceedings
Publication Type: Proceedings
Publication Acceptance Date: November 20, 2012
Publication Date: November 23, 2012
Citation: Pantin Jackwood, M.J. 2012. Viral enteric infections of poultry. International Seminar on Poultry Production and Pathology Proceedings. CDROM. Technical Abstract: Enteric diseases cause great economic losses to the poultry industry mostly from depressed weight gains, impaired feed efficiency, and decreased flock uniformity. Enteric syndromes have been described in both young turkeys and chickens and likely result from infection by a mixture of pathogenic agents in conjunction with nutritional imbalances, poor management, environmental conditions, and stress. In addition, the age and immune status of the birds, and their genetic background, also affect the clinical presentation of the disease. Many multifactorial enteric disease syndromes have been described in young turkeys. Poult enteritis complex (PEC) is a term frequently used that encompasses several infectious intestinal diseases of young turkeys including poult enteritis mortality syndrome (PEMS), infectious enteritis of turkeys, stunting syndrome of turkeys, poult enteritis syndrome (PES) and others. Clinical signs associated with PEC include diarrhea, growth depression (stunting and runting), poor feed conversion, secondary nutritional deficiencies, immune dysfunction, and mortality. Similar enteric syndromes have also been described in young broilers and given several names including malabsorption syndrome (MAS), runting and stunting syndrome (RSS), infectious stunting syndrome, pale bird syndrome and others. Among the most common clinical signs reported are: poor growth, diarrhea, abnormal feathering, pigment loss, proventriculitis, bone abnormalities, lymphoid atrophy, and increased mortality. Characteristic microscopic lesions include villous atrophy of the small intestine and a distention of the crypts of Lieberkühn (cystic enteropathy/enteritis). Many viruses, alone or in combinations, have been associated with enteric diseases in poultry including astroviruses, parvoviruses, reovirus, rotaviruses, adenoviruses, picornavirus, and other small round viruses. Currently, there are no effective commercial vaccines available for enteric viruses of poultry. Good management practices can help reduce or eliminate exposure of young birds to enteric viruses, but the ubiquity and genetic variability of the many enteric viruses make it difficult or impractical to keep commercial flocks free of infection. Control of enteric viruses is best accomplished by maintaining the premises free of these agents when possible, by implementing biosecurity measures that prevent the entrance and interrupting transmission of these viruses.