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Toxoplasma gondii is a widely prevalent protozoan parasite that causes serious toxoplasmosis in humans and animals.The present study aimed to determine the genetic diversity ofT.gondii isolates from pigs in Jiangxi,Sichuan,Guangdong provinces and Chongqing Municipality in China using multilocous polymerase chain reaction:restriction fragment length polymorphism (PCR:RFLP) technology.A total of 38 DNA samples were extracted from hilar lymph nodes of pigs with suspected toxoplasmosis,and were detected for the presence of T.gondii by semi:nested PCR ofB 1 gene.The positive DNA samples were typed at 11 genetic markers,including 10 nuclear loci,namely,SAG1,5:SAG2 and 3:SAG2,alternative SAG2,SAG3,BTUB,GRA6,c22:8,c29:2,L358,PK1,and an apicoplast locus Apico.Twenty:five of the 38 DNA samples were T.gondii B 1 gene positive.Complete genotyping data for all loci could be obtained for 17 of the 25 samples.Two genotypes were revealed (ToxoDB PCR:RFLP genotypes #9 and #3).Sixteen samples belong to genotype #9 which is the major lineage in mainland China and one sample belongs to genotype #3 which is Type Ⅱ variant.To our knowledge,this is the first report of genetic typing ofT.gondii isolates from pigs in Jiangxi,Sichuan province and Chongqing municipality,and the first report of ToxoDB #3 T.gondii from pigs in China.These results have implications for the prevention and control of foodborne toxoplasmosis in humans.