Effect of dietary conjugated linoleic acid supplementation on the growth, lipid metabolism, and plasma lipid levels of juvenile Amur sturgeon ( Acipenser schrenckii Brandt, 1869).

The study investigated the effects of dietary conjugated linoleic acid ( CLA) on the growth, lipid metabolism, and plasma lipid levels of juvenile Amur sturgeon Acipenser schrenckii. In the study design, fish were initially fed a carbohydrate-enriched diet to obtain 'high-lipid or obese' fish plus a control ( NC). In the second step, the high-lipid fish were divided into four groups and fed increasing levels of CLA at 0% ( MC0), 0.5% ( MC0.5), 1.0% ( MC1.0), and 2.0% ( MC2.0) in their diet. The initial control fish ( NC) and the other four groups ( MC0-2.0) were set up as an experimental series. Each group had three replicate tanks and 15 fish in each tank. After 6 weeks of feeding, specific growth rates and the condition factor were significantly reduced in the 1.0 and 2.0% CLA-supplemented groups compared with the initial control ( NC) and MC0 group. Body lipid content in the 2.0% CLA group was also significantly lower than in the control and other experimental groups. Compared with the MC0 group, lipid liver content in the 2.0% CLA-supplemented group decreased significantly. Total serum cholesterol was significantly lower in the 1.0% and 2.0% CLA-supplemented groups. Serum high-density lipoprotein cholesterol was significantly lower in the 2.0% CLA group than in the MC0 group. There were no differences in survival rate, feed conversion efficiency, body moisture, body protein content, hepatosomatic index, serum triglyceride, or low-density lipoprotein cholesterol among all experimental groups. The results suggest that adding CLA to fish diets is advisable as it can reduce growth and lipid accumulation in both the body and liver, and affect the regulation of blood lipid levels in juvenile Amur sturgeon. [ABSTRACT FROM AUTHOR]