title: A serological survey for avian infectious bronchitis virus and Newcastle disease virus antibodies in backyard (free-range) village chickens in Mexico.
abstract: 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 that were positive for antibodies to IBV and nine of the villages had chickens that were positive for antibodies to NDV. This suggests that IBV may be responsible for a large proportion of the respiratory disease observed in backyard chickens in Yucatan. The implications of these findings are discussed, including the highly susceptible status of the backyard chickens in Yucatan to NDV and the possibility of this virus being one cause of the syndrome known as mortandad by the local people.
authors.affiliation: Departamento de Virologia, Facultad de Medicina Veterinaria y Zootecnia, Universidad Autonoma de Yucatan, Merida Yucatan, Mexico.
authors.forename: E J
authors.initials: EJ
authors.lastname: Gutierrez-Ruiz
authors.forename: G T
authors.initials: GT
authors.lastname: Ramirez-Cruz
authors.forename: E I
authors.initials: EI
authors.lastname: Camara Gamboa
authors.forename: D J
authors.initials: DJ
authors.lastname: Alexander
authors.forename: R E
authors.initials: RE
authors.lastname: Gough
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D002645:Chickens; D016000:Cluster Analysis; D018352:Coronavirus Infections / Q000453:epidemiology / Q000276:immunology / Q000662:veterinary; D006385:Hemagglutination Inhibition Tests / Q000662:veterinary; D001351:Infectious bronchitis virus / Q000276:immunology* / Q000302:isolation & purification; D008800:Mexico / Q000453:epidemiology; D009521:Newcastle Disease / Q000453:epidemiology / Q000276:immunology; D009522:Newcastle disease virus / Q000276:immunology* / Q000302:isolation & purification; D011201:Poultry Diseases / Q000097:blood / Q000453:epidemiology* / Q000821:virology; D016036:Seroepidemiologic Studies
chemical_list: D000914:Antibodies, Viral