SEROLOGICAL SURVEY ON THE PREVALENCE OF CHICKEN ANEMIA VIRUS IN BACKYARD POULTRY FLOCKS IN BULGARIA

摘要

A total of 529 serum samples from backyard chickens originating from 22 villages in Western Bulgaria were tested for presence of chicken anemia virus (CAV) antibodies by means of commercial enzyme-linked immunosorbent assay (ELISA) kit. Three hundredninety one samples were submitted to the laboratory in a screening programme for surveillance of avian influenza (AI) and originated from birds with unknown production type, age and sex. Another set of 138 samples was collected for the purposes of the study as a representative part of the home-reared indigenous chickens in three villages (82 hens and 5 roosters above one-year old, and 51 chickens aged 4-18 weeks). CAV reagents were detected in all villages surveyed with seroprevalence rates ranging from84.4 to 100. Significant association between the seropositivity and age of birds tested was found, with more CAV reagents detected among adult hens and roosters than among chickens aged up to 18 weeks. The results from the study indicate that CAV is widespread amongst backyard poultry population in Bulgaria. However, additional investigations are necessary to evaluate the epidemiological impact of infection among home-reared chickens and productivity losses due to CAV-related immunosuppression.