Isolation,Identification and Virulence Analysis of Porcine Epidemic Diarrhea Virus TX Strain

Porcine epidemic diahorrea virus( PEDV) TX strain was isolated from the feces of piglets suspected to be suffering from a severe diarrhea in Jiangsu Province. To investigate the occurrence and origin of diarrhea in piglet,porcine epidemic disease virus( PEDV),transmissible gastroenteritis coronavirus( TGEV) and porcine rotavirus( RV) et al were detected by RT-PCR. Typical coronavirus particles were observed by transmission electron microscopy( TEM) in feces samples. The phylogenetic tree was established by comparing the S1 gene amplifying from TX strain with other PEDV strains. In order to identified the virus pathogenicity,age of 5,15,25 days piglet were challenged with TX strain. The samples were only positive to PEDV detected by RT-PCR. The TX strain shared a highly homology of 94. 8%- 99. 3% with epidemic strains. All the piglets died after were challenged with virus,indicating a high pathogenicity.