Objective To understand the genetic background of the specific pathogen-free Yorkshire and Landrace pigs, imported from Canada by Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences.Methods The population genetics were investigated by using 19 pairs of microsatellite primers.Results In the Yorkshire pigs and Landrace pigs, 84 and 89 alleles, respectively, were detected at 19 microsatellites loci.The average polymorphic informa-tion content and mean heterozygosity in the Yorkshire pigs were 0.5271 and 0.5877, and in the Landrace population were 0.5652 and 0.6066, respectively.Because of the significant ( P<0.01) differences of alleles in different loci such as S0155,S0143,S0178,Sw857 and Sw936, it made them possible to be used to identify Yorkshire and Landrace pigs′breed. F-statistics showed that the differentiation within the population was small and genetic structure was stable.Conclusions Compare with the domestic pedigree large White and Landrace pigs, the SPF pedigree pigs imported from Canada are more stable in genetic structure, and can be used as laboratory animal models in animal science research.

In this study, a Specific Pathogen-Free (SPF) Bama miniature pig herd was established.The standards for breeding experimental pigs, genetic test and microbiological quality control had been drafted.The local standards of Heilongjiang province SPF technical specifications for microbiological monitoring of pigs had been formulated.The genetic and microbiological quality criterion had been used to control of the SPF pig herd.Classical swine fever virus (CSFV) and highly pathogenic porcine reproductive and respiratory syndrome virus (PRRSV) infection models of Bama miniature pigs were established, especially the infection miniature pig model of PRRSV was used to evaluated commercially vaccine.The comparison of the cytokine homology between Bama miniature pigs and domestic pigs showed that the Bama miniature pigs can be used to instead of domestic pigs as an ideal experiental animal.At present the SPF Bama miniature pig colonies have been widely used to study the mechanism of prevention and pathogenic in the classical swine fever virus, porcine reproductive and respiratory syndrome virus and porcine transmissible gastroenteritis virus and porcine circovirus and so on.The completion of the project solved the bottleneck problem of the experimental pig usage which provided a new ideal experimental animal for animal disease and life science research.