Submitted to: US-Japan Coop Pgm on Dev and Util of Natural Products Abstracts Proceedings
Publication Type: Proceedings
Publication Acceptance Date: October 18, 1995
Publication Date: N/A
Technical Abstract: Porcine reproductive and respiratory syndrome (PRRS) was first recognized as a new disease of swine in the late 1980's and the causative agent, the PRRS virus (PRRSV), was discovered in 1991. We investigated the protective immunity that develops in sows following an oronasal exposure to live PRRSV. Sows were immunized by an intrauterine exposure to the NADC-8 strain of PRRSV at the time of artificial insemination. The sows protective immunity was challenged at 90 days of gestation by an oronasal exposure of the NADC-8 virus. Protective immunity was evaluated by the presence or absence of transplacental infection and the presence or absence of PRRSV in the alveolar macrophages of the sow. Results indicate sows can develop a homologous protection and this protection may be life-long. In addition, sows may develop a heterologous protection to antigenically distinct isolates of PRRSV; however, this protection may be of a short duration.