Evaluation of the effectiveness of two infectious bronchitis virus vaccine programs for preventing disease caused by a California IBV field isolate.
Infectious bronchitis virus CA99 serotype was isolated from several broiler flocks in Northern California. The virus caused late-onset respiratory disease and increased airsacculitis condemnation in affected flocks despite the use of an established infectious bronchitis virus vaccination program. An experimental study compared Holland/Arkansas and Massachusetts/Arkansas vaccination protocols to determine the efficacy of commercial infectious bronchitis virus vaccines in reducing respiratory disease and airsacculitis lesions found at processing that were associated with a CA99 field isolate. All vaccination groups were given Massachusetts/Connecticut strains of infectious bronchitis virus vaccines at age 1 day followed by vaccination with either Holland/ Arkansas or Massachusetts/Arkansas vaccine strains at 18 days of age. Birds were challenged at age 31 days with a CA99 field isolate. Gross pathology, histopathology, and virus isolation were evaluated. Chickens vaccinated with Holland/Arkansas had marginally better protection against CA99 challenge than chickens vaccinated with Massachusetts/Arkansas, although differences were not statistically significant.
Martin
Michael P
MP
University of California at Davis, School of Veterinary Medicine, Department of Population Health and Reproduction, 1 Shields Avenue, 1114 Tupper Hall, Davis, CA 95616, USA. michael_martin@nscu.edu
Wakenell
P S
PS
Woolcock
P
P
O'Connor
B
B
D000400:Air Sacs / Q000473:pathology; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D002140:California / Q000453:epidemiology; D002645:Chickens / Q000821:virology*; D018352:Coronavirus Infections / Q000276:immunology / Q000473:pathology / Q000517:prevention & control / Q000662:veterinary*; D001351:Infectious bronchitis virus / Q000276:immunology*; D011201:Poultry Diseases / Q000276:immunology* / Q000473:pathology / Q000517:prevention & control* / Q000821:virology; D013997:Time Factors; D014132:Trachea / Q000473:pathology; D014765:Viral Vaccines / Q000276:immunology*
D000914:Antibodies, Viral; D014765:Viral Vaccines