Heat ameliorative effects of rumen protected niacin supplementation in lactating Surti buffaloes

Niacin may cause evaporative thermolysis through cutaneous hyperemia, vasodilation, increased sweating rate and decreased skin temperature. It is antilipolytic and can improve metabolic responses. Heat stress ameliorative effects of rumen protected niacin (RPN) supplementation in lactating Surti buffaloes during summer has been investigated in present study. Fourteen lactating Surti buffaloes were divided into two groups (Control-T1, N=7; RPN-T2, N=7). T2 (RPN) group was supplemented with RPN 6 g/ animal/ day in two divided dose for 4 weeks. Meteorological, physiological, sweating rate and skin temperature parameters, milk yield and composition were recorded at weekly intervals. Hematological and biochemical analytes were analyzed at week 1 and 4. RPN supplementation decreased physiological parameters RT, RR and TT; increased (P≤0.05) sweating rate and decreased (P≤0.05) skin surface temperature; increased (P≤0.05) TEC, Hb, HCT, LYM and decreased (P≤0.05) GRAN in hematological profile; increased (P≤0.05) glucose and decreased (P≤0.05) cholesterol, triglyceride, NEFA and BHB among biochemical metabolites and increased (P≤0.05) GSH and SOD and decreased (P≤0.05) LPO in oxidative stress profile. RPN supplementation increased milk yield and milk fat.  It was concluded that supplementation of rumen protected niacin in lactating Surti buffaloes increases sweating rate, reduces oxidative stress and increases milk fat and milk production.