Submitted to: United States Animal Health Association Proceedings
Publication Type: Proceedings
Publication Acceptance Date: November 1, 1999
Publication Date: November 1, 1999
Interpretive Summary: Interpretive Summary not required.
Technical Abstract: Progress was reported for research conducted at the Southeast Poultry Research Laboratory on exotic and emerging diseases of poultry. For avian influenza, the Hong Kong H5N1 influenza viruses from 1997 caused severe disease and death in seven different species of poultry and laboratory mice. The 1999 H5N1 viruses caused severe illness and death in chickens but not mice. For Newcastle disease, field isolates from poultry in the U.S. were found to be of low virulence similar to vaccine strains, but the former had a more thermostable hemagglutinin. This suggests three more thermostable field strains could have been derived by selection from vaccine strains that contained heterogenous NDV populations and that minor antigenic changes may be a consequence of that selection. The avian pneumovirus from Colorado caused upper respiratory disease in turkeys but replication of the virus was only detected for 4 days after inoculation. For Poult Enteritis Mortality Syndrome (PEMS), a small round virus and a novel reovirus were isolated from the thymus. The small round virus reproduced a PEMS-like disease but not the reovirus. The small round virus may be a population of viruses containing at least an astrovirus.