Effect of dietary conjugated linoleic acid (CLA) on the growth and lipid metabolism of geese and fatty acid composition of their tissues
The objective of this study was to determine the effects of conjugated linoleic acid (CLA) oil supplementation on the growth performance and lipid metabolism in geese and the fatty acid concentrations in their liver and muscle tissues. One hundred and ninety two one-day old geese were randomly assigned to one of four dietary treatments. The diet in Group A, the control, contained 2.5% soyabean oil, that in Group B 2.0% soyabean oil and 0.5% CLA, that in Group C 1.0% soybean oil and 1.5% CLA and that in Group D 2.5% CLA. The birds were fed for 56 days. No significant effects were observed in body weight and body weight gain between Groups B, C and the control, but these parameters were significantly lower in Group D compared to the control. The feed intake, feed conversion ratio (FCR) and abdominal fat percentage (AFP) were significantly lower in the groups receiving CLA in their diets compared with the control. Dietary CLA altered serum lipid concentrations by decreasing total cholesterol, triglyceride and low density lipoprotein-cholesterol concentrations, the atherogenic index and activity of lipoprotein lipase, and increased serum concentration of high density lipoprotein-cholesterol. The fatty acid composition of the liver and muscle tissues showed significant increases in the biologically active cis-9, trans-11 and trans-10, cis-12 CLA isomers in the geese fed increasing levels of CLA. The supplementation of CLA to the geese led to significant increases in saturated fatty acid concentrations and significant reductions in the monounsaturated fatty acid concentrations in liver and muscle tissues. The results clearly demonstrated that geese can successfully incorporate CLA in their liver and muscle tissues, thus producing a healthy food for humans.
Keywords: Conjugated linoleic acid, geese, growth, lipid metabolism, fatty acid composition
South African Journal of Animal Science Vol. 38 (1) 2008: pp. 12-20