Vírus da anemia infecciosa das galinhas: perfil sorológico em matrizes pesadas e presença do vírus em sua progênie

Abstract

The epidemiological study of the chicken infectious anemia virus (CIAV) must include the evaluation of breeders and their progeny. For broiler breeders, in particular, it is essential that this knowledge will enable the adoption of flock management strategies to result in economical benefit. This study describes the evaluation of a broiler breeder enterprise in the State of Minas Gerais, Brazil, in view of the importance of CIAV for the ideal health and productivity. Serum and embryonic samples were obtained for ELISA and PCR analyses. The same hens sampledfor serum were separated for egg incubation and embryonic sampling. The abdominal organs of embryos at 20 days of incubation were collected for nested-PCR in pools of 6 embryos per flock. Production data of the progeny broilers of these breeders were obtained for analysis.Relating to antibody detection and its association to CIAV genome in embryos, results have shown that flock reactivity levels above 97,22% reflected in zero transmission to the embryo, as determined by PCR. Antibody occurrence is due to natural challenge before sexual maturity inmore than 90% of tested flocks. Challenge is believed to have occurred between weeks 12 to 15 of age, as antibodies were detected from 17 weeks of age onwards. Evaluated flocks have apparently been under natural challenge that enabled serum conversion as detected from week17 of age. Such condition has ensured protection to the breeders and their progeny, as such breeder will not transmit CIAV vertically and passive antibodies will be protective to early horizontal challenge. Production data are corroborative of sera and PCR results.