Prevalence of PCV2 in the cord blood of newborn pigs in vaccinated farms

摘要

Porcine circovirus type 2 is ubiquitous in the swine population. PCV2 transmission occurs horizontally from pig to pig and vertically from dam to pig. PCV2 crosses the placenta during viremia in the dam at any stage of gestation. Pregnant dams may notshow clinical signs even though they are viremic at farrowing. This late viremia may lead to PCV2 viremic pigs at birth. PCV2 infection in utero can be diagnosed by demonstrating PCV2 antibodies or PCV2 DNA in live born pre-suckle serum samples and in the tissues of stillborn pigs. In a previous study, a 21% and 43% prevalences of PCV2 antibodies and DNA respectively were reported in pre-suckle serum of pigs from five healthy swine farms in North America. The prevalence of PCV2 viremia in other pig populations, including farms with high production performance and under PCV2 vaccination schedules for gilts or sows is unknown. The objective of this study was to determine PCV2 prevalence in pre-suckle samples of newborn pigs in five farms including highperforming herds without clinical PCVAD.