Investion Of Classical Swine Fever Immue Situation And Procine Reproductive And Respiratory Syndrome Under No Immune On Large-scale Pig Farm In Guangxi

Currently,classical swine fever(CSF)mainly presents the form of atypical,recessive and chronic;Recessive infected pigs become the continuous source of infection,causing swine breeding disorder in clinical symptoms;the epidemic way mainly be sporadic outbreak,no rare large-scale outbreak.Based on the current characteristics of CSF,monitoring swine fever immune and immune antibody levels for swine fever for the CSF control,prevention and eliminate the pigs which have atypical symptoms is very important.Highly pathogenic porcine reproductive and respiratory syndrome virus(HP-PRRSV)is a variation virus and different from classical PRRSV,causing high morbidity,high mortality and low cure rate on clinical symptoms.HP-PRRSV often mixed infection with other virus,causing the illness complication and the outbreak of HP-PRRSV also has a certain spatial distribution characteristics.To understand the CSF antibody levels of sows group,lactation piglet,weaning piglets,and the gilt immune in a large-scale pig farms,and PRRS antibody levels non immune from the pigs,the serum samples were collected from a large-scale pig farms between 2009-2011 in this study.And the antibody titers of CSF after immuning and PRRS antibody titers were detected,the results of the antibody titers from breeding pigs effected on lactation piglet and weaning piglets were analyzed,and the epidemic situation of PRRSV was researched,this result provide a reference for the prevention and control measures of PRRSV.From 2009 to 2010,the antibody qualification rate of CSF of the pigs from four scale pig farms had greater difference after classical swine fever vaccine immunization which was under the same immune process,.Only the CSF antibody positive rate of the respective scale pig farm increased to 85%in 2011.There were low antibody positive rate in lactation piglet and weaning piglet in 2009 and 2010.The dispersion of the lactation sows and pregnant sows from various large-scale pig farms in 2009-2011 was exceed to 20%and there were the greater difference between individual antibody levels of pigs.The CSF antibody positive rate was negative correlated with the dispersion of antibody.The qualification rate of CSF antibody decreased association with the increase of parity of the sows,the CSF qualification rate from more than four parities lactation sows were lower than the qualification rate of one,two,three,and four parity sowsThe pigs from the scale pig farms did not be immunized,but the PRRS positive antibody were detected,this result shows that the pigs from these farms infected with the PRRSV or have been infected with PRRSV.In 2009,2010 and 2011,pregnancy,lactation sows,suckling piglets and weaning piglets have a low antibody positive rate and the result suggested that these pigs of large-scale pig farms may be in a relatively stable situation or pigs may be under the chronic persistent infection.There was no positive connection between lactation sows and pregnant sows under no PRRSV vaccination;More than four parities lactation sows were easier to infected with PRRSV than other pigs,and the antibody positive rate would increased,this result was different from the view about the parity in the CSF antibody positive rate,but the result were needed to further verification using the detection of the PRRSV from the lactation sows.