Isolation And Identification Of Pseudorabies Virus And Comprehensive Control And Purification Measures Of Pseudorabies In Large-scale Pig Farms

Pseudorabies virus(PRV)is the causative agent of Pseudorabies(PR).The disease is lethal to young piglets,and characterized by growth retardation and reproductive disorder.Since last century,Bartha-K61 vaccine was widely used in Chinese pig farms to control and eradicate PR and showed complete protection.However,since late 2011,a severe PR outbroke in many Bartha-K61 vaccinated pig herds,and causes significant economic losses.It has been confirmed that a newly emerged PRV variant is the causative agent and the commercial PRV vaccine Bartha-K61 provided poor protection against PRV variants.Phylogenetic analysis based on complete genomic sequence revealed that PRV-variant strains isolated in China,such as HeN1 or JS-2012,displayed marked sequence divergence compared to European and American strains.Therefore,it is urgent to develop a highly efficient disease surveillance and control system to prevent PR outbreak.In order to establish an complete and effective disease surveillance and control system,in the present study,tissue samples were collected from PR outbroke pig farm in Henan Province.According to the PCR and sequencing analysis,a PRV strain was isolated and designated as PRV-HN15.The isolated PRV-HN15 was identified by IFA,growth-curve and pathogenicity test in mice.And,the bioinformatic analysis of gE suggested that PRV-HN15 is a PRV variant.It indicated that the PRV variant is the causative agent for this PR outbroke.An complete disease surveillance and control system was designed and implement based on the background information of pathogens and PR antibody investigation.The production index has become regularly raised since the standard management strategy was practiced.This study provided an effective disease surveillance and control strategy for large-scale pig farm,and made significant contribution for PR eradication in China.