Heat stress induced changes in the major carcass traits and quantitative expression patterns of selective meat quality determining genes in Kanni Aadu Goats

Abstract

A study was carried out to evaluate the effect of heat stress on carcass traits and expression of Myostatin,Heat Shock Protein (HSP) 70and HSP110expression in skeletal muscle of Kanni Aadu goat. Twelve female (one year old) Kanni Aadu goats were randomly allocated into two groups of six animals each, control (KC) goats were placed in the thermo neutral zone (TNZ), i.e., control chamber, while the heat stress (KHS) goats were exposed to heat stress in hot chamber (40°C) for 45 days. Major carcass traits remained intact between the groups. Physico-chemical characteristics revealed a significantly (p<0.01) higher pH values, higher drip loss, cooking loss, lower water holding capacity and lower sarcoplasmic protein in Longissimus thoracis et lumborum (LTL)and muscle in KHS group as compared to the KC group. Heat stress significantly (p<0.05) increased Lightness (L*), decreased tenderness (higher shear and low tenderness score), whereas no significant effect could be observed in myoglobin, met-myoglobin and other organoleptic characteristics. The HSP110 and myostatinmRNA expression was significantly (p<0.01) higher in KHS as compared to KC group. Results of our study indicated that Kanni Aadu breed may be considered an extremely adapted breed with high climate resilience capacity as reflected by the intact meat production characteristics.