The influence of coconut oil (CO) supplementation (0, 25, 50 and 75 g/kg of concentrate)upon performance, nutrient utilization, rumen fermentation, blood biochemistry and carcasscharacteristics were assessed in lambs (4 males and 4 females in each treatment)between 15 d of age and 6 months. Lambs were allowed to suckle twice daily until 90 dof age. Concentrate and forage (Ailanthus excelsa leaves) were provided ad libitum for theduration of the experiment. Lambs were weighed at weekly intervals, and a metabolismstudy was conducted on six representative lambs from each group at 120 d of age to determinenutrient utilization and N balance. Blood samples and rumen liquor samples weredrawn at 180 d to determine blood biochemical and rumen fermentation characteristics.At 6 months of age all the male lambs were slaughtered and carcass traits were evaluated.Coconut oil intake was 7.1, 13.8 and 18.8 g/d in three treatment groups compared to zero incontrol. Pre- and post-weaning gain was similar while dry matter intake was higher in bothpre-weaning (L: P<0.001; Q: P<0.001) and post-weaning (L: P=0.001; Q: P=0.001) in control.Digestibilities of organic matter (P=0.013) and neutral detergent fiber (P=0.062) decreasedand that of ether extract increased (P=0.001) linearly with increased CO supplementation.The N retention decreased linearly (P=0.001) with increasing CO supplementation. Concentrationof total N and trichloroacetic acid precipitable N decreased at a decreasing rate (Q:P=0.051 and P=0.019, respectively) whereas ammonia N in rumen liquor decreased at anincreasing rate (Q: P=0.003) with increased CO supplementation. Coconut oil supplementationlinearly (P=0.006) reduced rumen protozoa population. Though the concentration ofserum glucose was similar, serum cholesterol and non-esterified fatty acids increased linearly(P<0.05) with CO supplementation both pre- and post-weaning. Pre-slaughter weight,dressed weight, eye muscle area, and body fat were similar in all the lambs. Coconut oil supplementationup to 50 g/kg is optimum in lamb rations due to improved feed conversionratio and production of a carcass with acceptable characteristics. Higher levels of COsupplementationdepressed growth and feed conversion due to its suppression of rumen protozoaand reduced fiber digestibility.
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