Summer season induced changes in quantitative expression patterns of different heat shock response genes in Salem black goats.

ABSTRACT

Research efforts of elucidating the molecular mechanisms governing heat shock response which imparts thermo-tolerance ability to indigenous breeds are very scanty. Therefore, a study was conducted with the primary objective to determine the impact of heat stress on the expression pattern of different heat shock response genes in the hepatic tissues of indigenous Salem Black goat. The study was conducted for a period of 45 days in twelve 1-year-old female Salem Black breed goats. The animals were randomly allocated into two groups of six animals each, C (n = 6; Salem Black control) and HS (n = 6; Salem Black heat stress). The C animals were maintained in the shed in comfort condition while HS animals were exposed outside to summer heat stress between 1000 h to 1600 h during experimental period. The animals were slaughtered at the end of study and their liver samples were collected for assessing the different heat shock response genes. Based on the results obtained from the study it was established that the heat shock protein 70 (HSP70), HSP90, super oxide dismutase (SOD), nitrous oxide synthase 1 (NOS1) genes were significantly (P < 0.05) down regulated. However, heat stress did not influence the expression pattern of heat shock factor-1 (HSF1) gene. The lower level of expression of all heat shock response genes may be due to less magnitude of heat stress in the study to induce cellular stress response in Salem Black goats.