Serological Investigation Of Neospora Caninum In Ten Species Of Animals And Sarcocystis Gigantea Of Tibetan Sheep In Qinghai Province

Neospora caninum(N.caninum)and Sarcocystis gigantea(S.gigantea)belong to the Apicomplexan protozoa—an obligate intracellular parasite—causing neosporosis and sarcocystosis that have a worldwide distribution and is very harmful to both human health and the livestock industry.This study focused to N.caninum and neosporosis to development an indirect ELISA test based on recombinant Nc SAG1 and Nc GRA7 protein to detected the Ig G and Ig M antibody levels of N.caninum in 4134 sera samples from ten species of animals in Qinghai Province.The results show that when both r Nc SAG1 and r Nc GRA7 were used as diagnostic antigens,the seropositive rates of the specific-N.caninum Ig G and Ig M antibodies in all investigated animals were 10.3%(425/4134)and 25.4%(1048/4134),respectively.The donkey was the most prevalent animal(97.3%,36/37)for Ig G positivity,for the Ig M antibody positivity,the horses was the most prevalent animal(91.8%,357/389).When a single r Nc SAG1 was used as diagnostic antigens,the seropositive rates of the specific-N.caninum Ig G and Ig M antibodies in all investigated animals were 13.3%(551/4134)and 31.3%(1293/4134).And for r Nc GRA7,there were 12.1%(502/4134)and 27.8%(1150/4134),respectively.Meanwhile,development an indirect ELISA test based on whole S.gigantea cyst protein to detected the Ig G and Ig M antibody levels of S.gigantea in 1332 sera samples from Tibetan sheep.The results show that the seropositive rates of the S.gigantea Ig G and Ig M antibodies in Tibetan sheep were 27.0%(359/1332)and 16.3%(217/1332),respectively.The 7.2%(96/1332)sera were determined to be both Ig G and Ig M positive samples,19.7%(263/1332)were single-Ig G seropositive,and a total of 121 in 1332 Tibetan sheep(9.1%)were single Ig M seropositive.The significant differences in the prevalent distribution of N.caninum and S.gigantea were found in the different altitudes.Combined with the results of the above investigations,there has a high infection rate of N.caninum and S.gigantea in livestock,grazing animals and pets in Qinghai province,and should be taken seriously.In conclusion,this study laid a solid foundation for conducting in-depth epidemiological studies on N.caninum in animals and S.gigantea of Tibetan sheep in Qinghai,and provided scientific data for development diagnostic methods for protozoosis and sound prevention and control measures.