Association of Hsp70 Gene Polymorphism and Bull Semen Quality in Winter and Summer Seasons

Objectives of current study were to identify single nucleotide polymorphisms (SNP) in heat shock protein70 (HSP70) promoter gene of bulls (cattle and buffalo) and its association with semen quality traits and some enzymatic, hormonal and lipid parameters during winter and summer seasons. Semen samples of 37 animals (Cattle n=21 and buffalo n=16), were used in the study. Biochemical Parameter and hormonal profile were estimated. Qualities of some of fresh and frozen-thaw semen were evaluated. PCR-SSCP was used to detect SNPs and different patterns were sequenced. The study demonstrate all the measured biochemical parameters and hormonal profile of cattle and buffalo were significantly different (P 0.05) in winter as compared to summer. Results of PCR-SSCP and sequencing detected a new synonymous SNP 812 T C transition was the same in both species and could clear two genotypes TT and TC. Association analysis revealed significance difference (P 0.001) with all the fresh and some of frozen-thawed semen traits in cattle population and T allele seemed to be the favorable allele. Regarding to buffalo population, different genotypes has significant difference in term of fresh motility, frozen motility at 1h and viability index. The results of association between biochemical and hormonal parameters there were no significance except for Aspartate-aminotransferase (AST) in cattle population and T3 level in buffalo population and C allele appeared to be the favorable allele. This the first study concerned with the association of HSP70 polymorphisms and semen quality, in winter and summer seasons in buffalo population. Conclusion: High temperature has negative impact on semen quality. Biochemical and hormonal profile can be used as good indicator for semen value. Polymorphisms in HSP70 gene can affect semen quality. We suggest to be used in artificial insemination programs as marker assisted selection for anti-heat stress and good reproductive bulls.