Hepatic Expression of Genes Related to Fatty Acid Biosynthesis during Tropical Summer in Broilers: Effect of Organic Selenium Supplementation

Abstract

Background: The physiological responses during adaptation to summer in poultry could be related to modulation of energy metabolism. Enhanced deposition of fat in spite of reduced feed intake seems to have an advantage under hot conditions. Thus, the present study was conducted to investigate the seasonal status of de novo synthesis of fatty acids in broiler chicken (Gallus gallus) and its response to organic selenium supplementation. Methods: The study was conducted in two phases, one during autumn and the other during summer, with a total of 300 birds as autumn control, summer control, group-I (0.3 ppm SeMet), group-II (0.6 ppm SeMet) and group-III (0.9 ppm SeMet) groups. Blood samples and hepatic tissues were collected at 21 and 42 d for further analysis. Result: An elevation in serum lipid profile, glucose, cortisol and T4 levels was observed during the summer while the T3 concentration decreased compared to the autumn. The hepatic expression of Acetyl Co. A carboxylase α (ACCα) and Fatty acid synthase (FASN) was increased at 21 d, while it was decreased at 42 d during summer in broilers. Serum total cholesterol levels and LDL levels decreased with SeMet at 0.6 and 0.9 ppm levels. The expression of hepatic ACCá and FASN genes was decreased with selenium supplementation at higher levels. Increased serum total cholesterol levels were associated with lower de novo fatty acid synthesis at 42d during summer in broilers.