Genetic Polymorphism Of Hstn Gene And Its Associationswith Somatic Cell Score And Milk Production Traits In Chinese Holstein

Mastitis is the most common diseases and costs most to dairy, furthermore,mastitis also pose a potential threat to the health of consumers. So, the prevention andtreatment of mastitis.is of great significance.Mastitis resistance breeding in dairy cattle is an important way to reduce mastitisincidence and to reduce disease damage. With the development of biotechnology,marker-assisted selection as a symbol of molecular breeding in dairy cattle breedingshow significant advantages and enormous potential. The key of mastitis resistancemarker-assisted selection is the positioning of the dairy cow mastitis related gene, inother words, the QTL-mapping. The major methods for QTL-mapping aremarker-QTL linkage analysis and candidate gene analysis, both using molecularbiology techniques.Antimicrobial peptides play an important role in host innate immunity. TheHSTN gene, which discovered recently, is a new bovine antimicrobial peptide gene,and the products of HSTN gene, histatherin, shows very significant bactericidalactivity in vitro against Escherichia coli, Staphylococcus aureus and Candida. So,HSTN gene may be used as a candidate gene of mastitis and may be used in molecularmarker-assisted selection. However, there is not any report about the relationshipbetween the HSTN genes and mastitis.In this study, we use the bovine HSTN as the candidate gene and choose736Holstein cows as the study groups from farmâ…  and farmâ…¡of Jinan Jiabao dairy,Qingdao High-yield dairy and Qingdao Ott diary, which all participated in the DairyHerd Improvement plan. we detected the polymorphism of HSTN gene by DNAsequencing and polymerase chain reaction-restriction fragment length polymorphismassay (PCR-RFLP) in736individuals from three Chinese cattle breeds. Three novelsingle nucleotide polymorphisms (SNPs)(g.-866T>A, g.107T>C,and g.11124T>G) were detected. Least squares analysis showed that the g.-866T>A-AA genotype isrelated with lower SCS while the g.-866T>A-CC genotype is related with higher SCS;the g.-866T>A-AA genotype and the g.11124T>G-GG genotype are both related withlower fat rate; the g.-866T>A-AA genotype is related with higher305d milk yield.This study can be used as a reference to the application of HSTN gene inmarker-assisted selection, but further study is needed to clarify the role of the HSTNgene in mastitis.