Gene Detection And Genotyping Of Swine Torque Teno Virus And Porcine Circovirus Type2at Suburbs In The Shihezi And Beitun

The swine Torque Teno virus (TTV) has higher infection rate in most pig farms of theworld. Human beings infected with Human TTV may get hepatitis. The circovirus type2(PCV2) is one of the important pathogens which induce mortality and morbidity of pig. Inorder to investigate the swine TTV infection around Shihezi and Beitun, and to understand thesynergistic effect between the swine TTV and the circovirus type2, Polymerase ChainReaction (PCR) detection of TTV and PCV2was implemented, the genotypes of the isolatedstrains were analyzed.In our study,206anticoagulant blood from Shihezi slaughterhouse,72anticoagulant bloodfrom Beitun slaughterhouse, were randomly collected.10anticoagulant blood of sow pig and50anticoagulant blood of piglets were collected from pig farm around Shihezi Region. Theblood genomic mimiprep kits produced by Kangwei century Company were used. Followinginstruction, the DNA was extracted from anticoagulant blood. According the documents, threepairs of primers were synthesized, and the PCR detection method were established for testingTTV1, TTV2and PCV2. Based on the PCR methods of TTV1and TTV2, the reactioncondition was optimized, and the Double PCR testing methods to TTV1and TTV2was alsoestablished. Using the established PCR testing methods, the collected samples were checked.The PCR products of some positive samples were purified with agarose gel purification kitand were TA cloned, and then sequenced after PCR check. The main results are as follows:1. In Shihezi and Beitun, the infection rate of swine TTV1, TTV2and PCV2were41.4(140/338),21.3(72/338) and4.3(12/278), respectively. TTV1and TTV2mixed inflectionrate were8.9(30/338).2.Among8positive PCV2samples, there were five cases coinfected by TTV1and PCV2,one case coinfected by PCV2and TTV2, one case coinfected by the three virus at the sametime, one case infected by PCV2only. Five clinical pigs infected by PCV2were collectedfrom pig farms around Shihez, given necropsy examinations, detected by PCR method. Itshowned that the five cases were coinfected by PCV2and TTV.3.Some positive samples were squenced. The gene sequence of the isolated strains werealigned with known TTV1, TTV2and PCV2sequence in Genbank. It was shown that thehomology of TTV1between our sequence and known squences was82.34%-95.59%, thehomology of TTV2and the known squences was83.75%-96.17%, the homology of PCV2and the known PCV2a squences and the PCV2b squences was86.4%-87.4%,92.9%-96.4%,respectively. It showned that the isolated PCV2strains were genotype2b.4.Double PCR test method for TTV1and PCV2was established. It showed that therewas no significant difference between Double PCR results and TTV1PCR results or PCV2PCR results.