To study the breed resources,protection and utilization of Wadi sheep,body conformation and appearance of Wadi sheep were observed,and the body size and weight,production performance,and reproductive performance were measured.The results showed that Wadi Sheep was an excellent breed in Shandong Province,which had advantages in high fecundity and strong adaptability.This paper introduces the breed characteristics,the situation of resources,and progress on breeding research for Wadi Sheep,and gives an advice on the protection and utliization.

Porcine reproductive and respiratory syndrome virus(PRRSV) continues to be a threat,and causes huge economic losses in the swine industry.According to serotype and genetic differences,PRRSV can be divided into European type and American type.Europe type occurs mainly in Europe,the North American type occurs mainly in the Americas and Asia Pacific.China's annual import of live pigs from the United Kingdom,France and other European countries accounted for about 40% of the total number of imported live pigs,but rarely reports on the European type PRRSV.Based on the whole genome sequences of PRRSV North American strains and PRRSV European strains in the GenBank,two pairs of specific primers were designed to amplify the respective genes.The whole procedure can be completed within 3 hours,and this method is suitable for quick analysis and characterization of a large quantity of samples.

To investigate the polymorphism of major histocompatibility complex ⅡDRB1(MHC-DRB1) in Wadi sheep,the second exon of this gene in 82 Wadi Sheep was amplified by nested PCR and the amplified products were characterized by RFLP technique using 2 restriction enzymes,ie,SacⅠandHaeⅢ.The results showed that the extensive polymorphisms of the exon2 of MHC-DRB1 were found at two loci digested with SacⅠandHaeⅢ,respectively,and these sites were controlled by two,five alleles,respectively.As some base mutations were found in MHC-DRB1locus,and according to the results in this paper,fifteen genetypes were found in Wadi sheep.The new allele MHC-DRB1.D was identified only in these Wadi sheep populations.The nucleotide and predicted amino acid sequence alignments of MHC-DRB1 alleles provided the evidence for considerable variation among the five alleles.