Untersuchungen zum Auftreten des "Porcinen Reproductive and Respiratory Syndrome (PRRS)" in Sachsen-Anhalt. 1. Verlauf und betriebswirtschaftliche Auswirkungen in einer geschlossenen Sauengroßanlage innerhalb 20 Monaten nach Seuchenausbruch

The clinical signs, including reproductive disorders, and the results of serological investigations within a large breeding herd infected with PRRS virus are described. Litter size and the percentage of suckling and weaned pigs reared were both reduced over a period of some months. The acute phase of the disease lasted 10-12 weeks followed by a chronic stage of illness. There was a correlation between the duration of pregnancy, the proportion of pregnant sows, the number of live piglets per sow and the conception rate with the presence of infection. Acute infections were also associated with anoestrus and an increased culling rate due to infertility. Sows that recovered.from PRRS virus infection produced litters of normal size. Serological investigations indicated that infection persisted for at least 12 months after the initial onset of clinical signs. Financial losses within the breeding herd in 1991 were estimated to be some 442,831 DM