Effects of various levels of conjugated linoleic acid supplementation on fatty acid content and carcass composition of broilers

摘要

The effects of dietary conjugated linoleic acid (CLA) supplementation on growth performance, carcass quality, free fatty acid composition, and accumulation of CLA were investigated in broilers. Four hundred eighty 3-wk-old broilers were assigned to 4 dietary treatments (0, 0.5, 1.0, and 1.5% CLA) with 6 replicates of 20 chickens. Feed consumption and BW were recorded at every 5-d period. On d 42, carcass compositions were determined from 30 birds per treatment. There were no significant differences in average daily feed intake among the treatments. However, feed conversion ratio was highly significantly different (P < 0.01) between treatments, and average daily gain was significantly reduced by a supplement of dietary CLA (P < 0.05). Live weight and percentages of carcass, drumstick, thigh, boneless thigh, pectoralis major, and pectoralis minor were not influenced by the dietary CLA. Abdominal fat was significantly reduced (P < 0.01) with the increased CLA level in the broilers' diets. Percentages of liver weight were significantly increased (P < 0.01) after the CLA treatments. Percentages of drumstick and boneless drumstick were significantly decreased (P < 0.05) by dietary CLA. In terms of free fatty acid composition in broiler meat, CLA addition significantly increased (P < 0.05) saturated fatty acids, especially in thigh muscle, whereas unsaturated fatty acids were unchanged. Accumulations of CLA in meat were significantly increased (P < 0.05) with increasing CLA level in the diet.