Molecular Epidemiological Investigation Of ORF3 Gene Of Porcine Epidemic Diarrhea Virus In 11 Provinces And Cities In China In

Porcine epidemic diarrhea(PED), caused by Porcine epidemic diarrhea virus (PEDV), is ahigh degree of exposure to intestinal infectious diseases of swine, characterized by severeenteritis, vomiting, diarrhea and dehydration. The disease is widely distributed in the world,causing serious economic losses to the world’s pig industry. Has become one currently of themost serious the infectious viral diarrhea of pig industry.At the end of2010, PED occurred in south China, subsequently, the disease has been foundin most province of China, the incidence and the mortality rate are very high. In order toinvestigate the prevalence of porcine epidemic diarrhea virusin China. From January toDecember2014, porcine intestine and fecal samples were collected from165piglets with waterydiarrhea and dehydration at42different farms in9provinces(Heilongjiang, Jilin, Liaoning, InnerMongolia, Hebei, Shandong, Shanxi, Jiangsu, Hunan)and2municipalities(Beijing, Tianjin) inChina. All the samples were detected by colloidal gold, RT-PCR and so on. Determine itsetiologic factors. The result is that there are25pig farms(59.52%) were infected with PEDVlonely of42different pig farms,11pig farms(26.19%) were infected with mixed infection ofTGEV and PoRV of42different pig farms,73samples(44.24%) were infected with PEDVlonely of165porcine intestine and fecal samples,55samples (33.33%) were infected withmixed infection of TGEV and PoRV of165porcine intestine and fecal samples. The rest diarrheapathogen is the other gastro-intestinal disease pathogen. The result showed that: PEDV isdominant in the diarrhea pathogen.According to the detection results of21strains of ORF3gene, composed of675nucleotides,Comparison with12strains of domestic and international reference strain sequence has beenregistered in GenBank, the homology was90.6%~100%. The results of homology comparisonfrom the domestic and foreign strains, The results of the homology comparison between thedomestic and foreign strains indicated that the current epidemic Chinese strains having lowhomology with the European strains and the earlier epidemic Chinese strains, while having highhomology with the Korean strains. The phylogenetic analysis of the thirty-three PEDV strainsbased on the ORF3gene demonstrated that the Chinese wild strains and the reference strainswere divided into two distinct groups.