Abstract: By serial passaging on ST cells,a transmissible gastroenteritis virus (TGEV)strain(TGEV JS2012)was obtained from intestinal contents of died piglets with clinical diarrhea symptom. This virus was proved to be TGEV by RT-PCR,direct immunofluorescence and animal regression test. The S gene of TGEV JS2012 strain primary aassages (P1TS)and the fiftith passages(P50TS),were amplified by PCR and then sequenced. Comparison of the S gene se-quences of P1TS and P50TS with 18 published TGEV strains with different origins showed that they can share 96.0%-99.9%homology of nucleotide sequences and 96. 5%-99. 9%homology of amino acids. Furthermore,the results of the phylogenetic tree analysis demonstrated that there was a close genetic relationship between P 1 TS strain and HN2002 or Miller M6 strain isolated from China and America respectively. Generally the result indicated the varia-tion of S gene between strains of different origins was not so obvious. The result also showed that a deletion of six bases happened in 1 124-1 129 location of the S gene of P50TS seemed to be similar to Purdue P115 strain which is an attenuated strain,indicating this deletion perhaps is related to the reduced virulence of TGEV.

Key words: TGEV, Isolation and identification, S Complete genome, Sequence analysis, Deletion

CLC Number: 

• S852.65