Effect of vitamin E supplementation on growth, nutrient utilization, mineral balance and immune status of arsenic exposed goats

Abstract

This experiment aimed to investigate ameliorative efficacy of vitamin E in the goat (Capra hircus) kids exposed to arsenic (As). Twenty-one Black Bengal male goat kids (4–6 months age, 6.71 ± 0.49 kg body weight) were divided into seven blocks of three animals in each after arranging them in an ascending order on the basis of their body weight and then one animal from each block was randomly allotted to three groups. The kids were fed either basal diet as such (control, T1), or supplemented with 60 mg As/kg diet (T2) and 60 mg As/kg diet + 250 IU vitamin E/kg diet (T3) for 180 days including a 6 days metabolic trial. Daily feed intake and fortnightly body weight were recorded throughout the experimental period. To assess humoral immune response, animals were inoculated with Pasteurella multocida inactivated antigen after 135 days of experimental feeding and blood samples collected on day 0, 7, 14, 21, 28 and 35 post-inoculation. For assessing cell mediated immune response, kids were exposed to phytohaemaglutinin-p antigen after 170 days of experimental feeding and skin fold thickness was measured up to 96 h of exposure. Growth rate, feed conversion efficiency and intake and digestibility of different nutrients viz. dry matter, crude protein, ether extract, acid detergent fibre and neutral detergent fibre did not vary (P>0.05) among the three groups. However, absorption as well as retention of As were higher (P<0.001) in both the As exposed groups (T2, T3) as compared to control group. Addition of As also adversely affected the retention of zinc (P=0.024), cell mediated immunity (P=0.014) and humoral immune responses (P=0.024), which were largely ameliorated by vitamin E supplementation.