Abstract
Black Bengal bucks (Capra hircus) were supplemented with 0, 0.2 or 0.4 mg elemental chromium (Cr) as chromium chloride hexahydrate per day for 70 days. Intake of dry matter (p<0.001), crude protein (p<0.001) and neutral detergent fiber (p<0.01) increased due to Cr supplementation. The apparent total tract digestibility of dry matter (p<0.01), organic matter (p<0.05), crude protein (p<0.001) and acid detergent fiber (p<0.01) improved and the total body weight gain and the live weight gain to feed intake ratio also increased (p<0.001) due to supplemental Cr feeding. The intake and apparent absorption (p<0.001) of Cr was enhanced due to its supplementation. The intake of copper, zinc, manganese and iron was also more (p<0.001) in the Cr supplemented bucks. As supplementation progressed, plasma glucose concentration was elevated particularly in 0.4 mg Cr supplemented bucks and a significant day x dose interaction effect (p<0.001) with this parameter. The activity of plasma alkaline phosphatase increased (p<0.001) and that of glutamate pyruvate transaminase in plasma decreased (p<0.01) in the Cr supplemented bucks. Supplemental Cr had minimal (p>0.05) effect on the plasma half life (k) and clearance rate of glucose (T1/2) during an intravenous glucose tolerance test. Area under the response curve from 0 to 180 minutes after glucose loading was lower (p<0.001) in the control group of bucks. The study revealed that Cr supplementation might promote growth and nutrient utilization in black Bengal bucks. However, little difference between the 0.2 and 0.4 mg Cr supplemented bucks suggested limited benefit of increasing the level of supplementation beyond 0.2 mg per day under the normal management regimes.