Comparative evaluation of dietary fiber levels on production, haemato-biochemical profile, antioxidant status and stress biomarkers in heat stressed mid lactation Murrah buffaloes.

Heat stress in livestock is a heeding concern, and the addition of optimum fiber to the diet is an option in balancing the metabolic heat load. This study evaluated the comparative effect of low, moderate and high dietary Neutral detergent fiber (NDF) levels on nutrient utilization, production, hormone levels, hemato-biochemical parameters, antioxidant status and stress indicator levels in mid lactation Murrah buffaloes (MY 9.2 ± 2.2, Parity 2.5 ± 1.5). Eighteen mid lactation female buffaloes were randomly allocated to three dietary treatments for 90 days: a total mixed ration (TMR) with 30.0% NDF (C1), 34.5% NDF (T1) and 37.0% NDF (T2). During the trial, THI ranged from 77.0 to 88.3, indicating that Murrah buffaloes were exposed to heat stress. Compared with the control, buffaloes fed 34.5% NDF diet exhibited a 4.5% increase in milk yield, accompanied by a 6.2% increase in NDF digestibility and a 15.4% reduction in serum NEFA concentration. A moderate dietary NDF level lowered respiratory rate, heat shock protein and increased intake, FCM, T3 and T4 levels. Plasma cortisol, albumin, globulin, BUN remained unaltered with altered fiber level except for increased total protein with high fiber. Antioxidant status remained unaffected with varying NDF supplementation except for increased SOD at moderate and high fiber levels. Milk fat and total solids increased at high NDF levels. Milk stress indicators unaffected with altered fiber levels but altered with respect to acceptable levels under stress conditions. Overall, an optimum dietary fiber level, improved nutrient utilization, production performance, antioxidant status, hormonal status and haemato-biochemical performance in lactating Murrah buffaloes.