The effect of conjugated linoleic acid on the fatty acid composition of different tissues and yolk lipids in pigeons

Abstract

Dietary conjugated linoleic acid (CLA) was reported to increase the levels of saturated fatty acids (SFA), to decrease monounsaturated fatty acids (MUFA) in egg yolk, liver and adipose tissue in chicken and quail. Hence, the objective of this study was to determine the effects of dietary CLA on the fatty acid composition of liver, breast muscle, abdominal adipose tissue and egg yolk lipids in pigeons. Eight established breeding pairs per group were fed either a commercially pelleted pigeon diet mixed with 0.5% safflower oil (SFO) or 0.5% CLA for 12 weeks. For fatty acid analyses, four eggs per group were collected at the 10th week of feeding. At the end of the 12th week of the CLA feeding, four pigeons per treatment were killed and liver, breast muscle and abdominal fat pads were obtained at necropsy. For fatty acid analyses, fats from liver, breast muscle, abdominal adipose tissue and egg yolks were extracted with chloroform : methanol (2 : 1, v/v). Dietary CLA had no effect on the fatty acid composition of the liver compared to the control. However, dietary CLA caused a significant increase in the level of SFA and a decrease in the level of MUFA in breast muscle, adipose tissue and egg yolk. Breast muscle, adipose tissue and egg yolk from the CLA-fed pigeons had 1.8-, 1.6-, and 1.5-fold increases in the ratio of C16:0/C16:1(n-7), respectively. Also the ratio of C18:0/C18:1(n-9) in breast muscle, adipose tissue and egg yolk from the CLA group increased 1.4-, 2.2- and 1.9-fold, respectively, compared to the control. Relative CLA (%) in the liver, breast muscle, adipose tissue and egg yolk from the CLA group was 0.71, 1.30, 2.14 and 1.22%, respectively. Control egg yolk contained only 0.06% CLA. This study showed that CLA altered the fatty acid composition of the related tissues and egg yolk when supplemented in the diet of pigeons.

South African Journal of Animal Science Vol. 35(4) 2005: 253-260