Porcine Reproductive And Respiratory Syndrome Epidemiology And Prevention Study

Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the major pathogens which could cause swine "heat fever syndrome" and immune suppression, resulting in secondary infections and immune failure. It has caused enormous economic losses to the swine industry.In order to investigate porcine reproductive and respiratory syndrome (PRRS) in Zaozhuang area, indirect ELISA method was used to detect1055serum samples of healthy swines (568of which immunized PRRS inactivated vaccine,361of which immunized PRRS attenuated vaccine and126of which was non-vaccinated animals) from March2008to December2010. The results show that the antibody positive rate of swines immunized with inactivated vaccine, attenuated vaccine and non-vaccinated animals was71.1%(404/568),88.1%(318/361) and63.2%(67/126) respectively.According to the PRRSV and swine fever virus (CSFV) genome sequences, two pairs of specific primers were designed for simultaneously detecting PRRSV and CSFV, then a multiple RT-PCR method was established.172swine clinical samples or serum samples collected from2008to2010in Zaozhuang piggery were detected by this method. The results showed that the percent of highly pathogenic PRRSV was56.4%(97/172) and CSFV was31.4%(54/172). The rate of mixed infection of two viruses was12.2%(21/172). It was indicated that PRRSV existed in the swine farms of Zaozhuang, and combined with CSFV infection which was also existent. According to the development of livestock breeding, swine breeding characteristics and epidemic situation in Zaozhuang area, we designed a series of comprehensive prevention measures which was in line with local conditions. Immunization, scientific management, drug prevention and so on were throughout the whole progress of swine production, which greatly reduced the damage on the swine industry.