Effect of Cottonseed Meal Fermented with Yeast on the Lipid-related Gene Expression in Broiler Chickens

ABSTRACT

Fermented cottonseed meal (FCSM) is widely used in poultry diets in China. This study was conducted to investigate the effect of FCSM on lipid-related gene expression in broilers. Initially, 180 broiler chickens (21-days-old, equal number of males and females) were randomly divided into three groups, with six pens per group and 10 birds per pen. The chickens in the control group were fed a diet containing unfermented cottonseed meal, and those in the treatment groups were fed with diets including either CSM fermented by Candida tropicalis (Ct group) or CSM fermented by Candida tropicalis plus Saccharomyces cerevisae (Ct-Sc group) until 64 days old. The results revealed that, compared with the control group (p 0.05), the mRNA expression of peroxisome proliferator-activated receptor alpha (PPAR-a) and lipoprotein lipase (LPL) were upregulated in the livers of Ct-Sc males. The expression of PPAR-a was also upregulated in the livers of Ct females. The expression levels of acetyl CoA carboxylase (ACC) and LPL in the liver of males and the expression of PPAR-a in the liver of females were significantly different between the Ct and Ct-Sc groups (p 0.05). However, gene expressions of fatty acid synthase (FAS) and liver fatty acid-binding protein (L-FABP) in the liver were not altered when the broilers were fed FCSM-supplemented diets (p>0.05). Likewise, the expressions of peroxisome proliferator-activated receptor gamma (PPAR-g) and LPL in the abdominal fat were not altered by the FCSM-supplemented diets (p>0.05). The results in this study indicate that CSM fermented by Candida tropicalis and Saccharomyces cerevisiaeeffectively regulated the genes involved in fatty acid b-oxidation and triglyceride hydrolysis in male broiler chickens. Furthermore, the effects of the FCSM-supplemented diets were significantly different between bird sexes and between yeast strains used in the fermentation process.