Clinical Research Of Highly Pathogenic Porcine Reproductive And Respiratory Syndrome (HP-PRRS) Vaccine (JXA1-R)

Highly pathogenic porcine reproductive andrespiratorysyndrome,also called HP-PRRS is a kind of deadly infectious diseases caused by porcine reproductive and respiratory syndrome virus(PRRSV).The disease is characterized by acute onset,rapid progress and extremely high mortality,occurring in multiple varied infectious foci.The infection of PRRS brings the breeding extremely serious economic loss.There are many different routes of transmission can be susceptible to infection of pigs—Contacting with infected equipments in the process of breeding;Contacting with infected Feces or urine through nose and mouth,etc.PRRS has strong characteristics of persistent infection,that also means PRRSV can e xist in pigs for a long period of time,and easily transfer to other sensitive swinery.Therefore,preventing the movement the infected pigs and protecting sensitive swinery is great significant in preventing the occurrence and spreading of the disease.In recent years,the fast development of PRRS gave huge prevention and control pressure to our countries’s pig industry.Compulsoryvanccination is the most important control strategy.Attenuated live vaccine as one of PRRS vaccine,has the characteristics of antibody appeared earlier long duration and better immune effects in homologous virius strains than inactivated vaccine.For testing the suitable conditions of PRRS vaccine’s using,guiding farmers to use vaccine better.In this experiment,we chooses attenuated live vaccine(JXA1-R)which was commonly used in GuangDong to immune swine.After immunization,testing lymphocytes and serum specific antibody in blood.Monitoring body weight change and viral nucleic acid’s duration.Comparing with the control group(normal saline injection).Analysising of the influence on animal organism after the vaccine immune.Results show that after 28days,the immune lymphocytes in experimental group raised from 7.585×10~9/L to 15.28×10~9/L,,and 100%pigs have antibody.Body temperature is relatively stable,and there is no obvious change in the weight.Above experiments proved that attenuated live vaccine(JXA1-R)could cause well immune efficacy and has little impact on body weight.According to the highly positive rate in detection of 28 days’virus nucleic acid,we suggest that the farmers in choosing a PRRS vaccine should be according to the actual situation in their own farm:when PRRSV is negative in farm,it is not recommended to choose attenuated live vaccine(JXA1-R).That could be helpful in reducing the risk of PRRS infection.