Abstract
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 Parameters and hormonal profile were estimated. Qualities of fresh semen and frozen-thaw semen were evaluated for motility, plasma membrane and acrosome integrities. 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 (P<0.001) with 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 alleles has no significance on any of semen traits. By study the association with biochemical and hormonal parameters there were no significance except for T3 in buffalo population and C allele appeared to be the favorable allele for T3 level even in summer season. This the first study concerned with the association of Hsp70 polymorphisms and semen quality, biochemical and hormonal parameters of semen in winter and summer seasons in buffalo population. Conclusion: High temperature has negative impact on biochemical and hormonal parameter consequently semen quality. Biochemical and hormonal profile can be used as good indicator for semen quality. polymorphisms in HSP70 gene can affect semen quality and suggest to be used in artificial insemination programs as marker assisted selection for anti-heat stress and good reproductive bulls.

Key words: HSP70, Polymorphism, Biochemical parameter, Hormonal profile, Semen quality