›› 2017, Vol. 44 ›› Issue (6): 1769-1777.doi: 10.16431/j.cnki.1671-7236.2017.06.027

Previous Articles     Next Articles

Etiological Investigation of Diarrhea in Newborn Piglets and Molecular Characterization and Genetic Variation Analysis of ORF3 Gene of PEDV in North Guangdong

NAN Wen-jin1,2, HU Hong-hui1,2, WU Jing-bo1,2, HUANG Jian-qiang1,2, PENG Guo-liang2,3, XIAO Zheng-zhong2,3   

  1. 1. Laboratory of Animal Disease, Shaoguan University, Shaoguan 512005, China;
    2. North Guangdong Collaborative Innovation and Development Center of Pig Farming and Disease Control, Shaoguan 512005, China;
    3. School of Agricultural Science and Engineering, Shaoguan University, Shaoguan 512005, China
  • Received:2016-10-08 Online:2017-06-20 Published:2017-06-28

Abstract:

In order to understand the main pathogen of newborn piglets diarrhea in North Guangdong region, 31 diarrhea samples were collected from six pig farms in North Guangdong, the pathogen of porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV) and porcine rotavirus (PoRV) were detected by Real-time RT-PCR, meanwhile, ORF3 gene of PEDV amplified from positive samples were sequenced and analyzed. Pathogen detection results showed that 83.87%(26/31) samples were positive for PEDV, all herds and samples were negative for TGEV and PoRV. The sequence analysis revealed that the ORF3 gene of 5 epidemic strains of PEDV were all 675 bp, homologies of nucleotides were 98.7% to 100.0%, and homologies with reference sequences of nucleotides were 94.5% to 100.0%, and some gene mutation in common nucleotides site. The results of gene phylogenetic trees showed that PEDV could be divided into two groups, PEDV genetic relationship between field strains in North Guangdong and some regions in China, Southeast Asia, North America, Europe from 2013 to 2015 was closer, classed as a gene subgroup, from 2011 to 2012 main epidemic strains in our country and vaccine strains classed as other two gene subgroups. These results indicated that PEDV infection was the main pathogen of newborn piglets diarrhea in North Guangdong region, as time passed, the PEDV epidemic strains gene presented a tendency of evolution and variation.

Key words: diarrhea in newborn piglets; etiology; porcine epidemic diarrhea virus; ORF3 gene; genetic variation

CLC Number: