Isolation,identification and pathogenicity of porcine epidemic diarrhea virus strain CH/GSMQ/2022
Feces and intestinal contents of pigs suspected with porcine epidemic diarrhea virus were collected from a farm in Minqin County,Gansu Province,China.After the suspected positive sam-ples were detected by RT-PCR,Vero cells were used to isolate and culture them in vitro.The suc-cessfully isolated virus was identified in the laboratory,and its whole genome sequence was ana-lyzed for genetic evolution.The pathogenicity was evaluated by animal regression test.The results showed that typical syncytial lesions could be observed when the PEDV-positive treatment solu-tion was inoculated with Vero cells in the 4th generation,and the virus titer in the 6th generation reached 10-4 75TCID50/mL.PEDV-like virions with a diameter of about 100 nm and a round shape with obvious capsular membranes and spikes were observed by electron microscopy.Whole genome sequencing analysis showed that the total length of this strain was 28 085 bp,which was far from the G1 subtype represented by the classical strain CV777(96.6％),and had a high homology with the G2b strains BC-2011-1,IA1,USA/Colorado/2013 and WELL(98.6％).This indicated that the strain belonged to the G2b epidemic strain.The animal regression test showed that the 5-day-old piglets developed vomiting,acute watery diarrhea,emaciation and mental depression within 12 h after the attack,and the symptoms worsened and died within 24 h.After autopsy,the infected piglets could be observed with stomach swelling,high intestinal heave,thin and transparent intesti-nal wall,and undigested milk clots inside.In summary,a PEDV G2b epidemic strain was success-fully isolated and identified in this study,and its whole genome sequence and pathogenicity were analyzed,providing research materials for future studies on PEDV gene function,pathogenic mech-anism and vaccine development.
PEDVisolation and identificationgenetic evolutionpathogenicity
万方数据
维普
