The incomplete elimination of PRRS virus using traditional methods - a retrospective case study in seven herds

摘要

In conjunction with a pilot study to test commercial application of filtration to prevent long distance transmission of PRRSv, a retrospective study was conducted in seven large (> 3000 sows) breeding herds to document the outcome of PRRSv eliminationprotocols that had been simultaneously implemented in each farm. The seven herds were located in swine-dense regions of southern Minnesota and northern Iowa. For the purpose of this study, all of the herds were analyzed based on the outcome of the PRRSvelimination protocols implemented on each farm at the same time that filtration was implemented. All herds were filtered using published technology. Additionally all seven herds implemented PRRSv elimination protocols via exposure to resident virus or vaccine, loaded with gilts and closed to new entries for at least 200 days.