Anti-PRRS Virus Infection Capability And Performance Of The CD163 Gene Mutation Large White Pig

Swine blue-ear disease is a serious pig infectious disease caused by the blue-ear virus,which causes huge economic losses to the pig industry every year.The blue ear virus infects pigs through the CD163 receptor that binds to the membrane of monocytes/macrophages.We used gene editing technology to knock out the CD163 gene in somatic cells,and then used nuclear transfer methods to successfully obtain CD163 gene mutant pigs.In this study,we first expanded the pigs with CD163 gene mutation.By crossing with 39 wild-type large white pigs of different pedigrees for two consecutive generations and cross-crossing them in the F2 generation,a breeding core group of CD163 gene mutant pigs with 5 pedigrees was established.In order to verify whether the CD163 gene mutant pigs are resistant to PRRS infection,we inoculated the CD163 gene mutant pigs with type I blue ear virus(CHsx1401)and type II blue ear virus virulent strain(JXwn06)and tested the CD163 gene mutant pigs on their ability to resist blue-ear virus infection.Through clinical observation records,pathological anatomy,histology,immunohistochemistry,serology and virus detection methods,our test results proved that the CD163 gene mutation homozygous pig has resistance to type I and type II blue ear virus.We further tested the effects of CD163 gene mutation on blood physiology,biochemistry and endogenous immunity of Large White pigs,and the results showed that there was no difference between CD163 gene mutation pigs and Large White pigs.More importantly,the CD163 gene mutation has no significant effect on the growth rate,reproductive performance,meat ratio,meat yield and other productivity measures of large white pigs.Through meat quality analysis and by feeding the meat to rats we showed that the meat quality of large white pigs with CD163 gene mutation is no different from that of control pigs,and its meat is safe and edible.The CD163 gene mutant pig is a successful model of gene editing targeted breeding in recent years.This research has laid the foundation for the breeding of new breeds of pigs resistant to blue ear disease.