| a serological survey for avian infectious bronchitis virus and newcastle disease virus antibodies in backyard (free-range) village chickens in mexico. | the commercial flocks in yucatan, mexico are free of newcastle disease virus (ndv) in its velogenic viscerotropic form, but little is known about the disease status of backyard poultry. a seroprevalence survey in 30 villages using haemagglutination inhibition (hi) tests for infectious bronchitis virus (ibv) and ndv antibodies was carried out from december 1997 to june 1998. the seroprevalences were 56.5% (95% ci 50-63%) for ibv and 2.2% (95% ci 0.5-3.8%) for ndv. all the villages had chickens th ... | 2000 | 11147278 |