Effect of melatonin supplementation on thyroid hormone and cortisol in buffalo calves under summer stress

Abstract

A study was undertaken to investigate the effect of melatonin supplementation on thyroid hormones (T3, T4) and cortisol in buffalo calves under summer stress. Twelve healthy Murrah buffalo male calves of 6 month to 1 year age group were taken for the study. Buffalo calves were divided into control (CG) and treatment (TG) group. In TG, Melatonin (18mg/50 kg BW) was injected subcutaneously, two times at 1st and 20th day. Hormones like T3, T4 and cortisol were estimated by Gamma coat TM (125I) RIA kits. Within and between the groups serum T3 and T4 level did not differ significantly (P>0.05), but higher level of serum T3 and T4 was observed in CG than TG. The significant (P