Abstract:

【Objective】 In order to provide data and scientific basis for reasonable utilization and protection of biodiversity, the genetic diversity and phylogenetic relationships of 12 pig breeds (8 pig breeds from Shandong Province, 3 introduced pig breeds and Meishan pigs) were studied. 【Method】 In the study, the PCR amplification, sequencing and data analyzing ways of biologic informatics were used. 【Result】 All the 8 pig breeds from Shandong Province shared common haplotype, had rather small genetic diversity within breeds and small mean genetic distances between breed too. The pig breeds from Shandong Province had rather small mean genetic distances with Meishan and Yorkshire too, but had big distances with Duroc and Landrance. Both the NJ phylogenetic tree and the classified measure based on four SNPs of CytB, which classify the pigs into European and Asian haplotypes, classified the above samples into 2 clades. One included all sample of pig breeds from Shandong Province excepted one haplotype of Luyan White pigs, Meishan pigs and two haplotypes of Yorkshire, and the other included Duroc, Landrace, part haplotype of Yokshire and one haplotype of Luyan White pigs. 【Conclusion】 Firstly, the pig breeds from Shandong Province had the common maternal ancestor, the genetic diversity were rather small within every breeds. Secondly, the introduced pigs were used as sire, not dam, to improve the growth performance and lean meat percentage of the pig breeds from Shandong Province. Thirdly, it was a convenient measure to use the 4 SNPs of CytB to detect the maternal blood of the new pig breeds (or synthetic lines) bred by Chinese and European pig breeds.

Key words: pig breeds from Shandong Province, mtDNA, CytB, genetic diversity, phylogenetic relationship