Effects of alfalfa saponin extract on the performance and cholesterol metabolism of laying hens

• Published in: PeerJ preprints
• Main Authors: Zhang, Senhao, Shi, Yinghua, Liang, Minggen, Li, Jia, Wang, Chengzhang
• Format: Journal Article
• Language: English
• Published: San Diego PeerJ, Inc 30.10.2015
• Subjects: Apolipoproteins; Bile; Cholesterol; Coenzyme A; Dietary supplements; Gene expression; Hydroxylase; Hydroxymethylglutaryl-CoA reductase; Lipid metabolism; Liver; Metabolism; Receptor density; Yolk
• ISSN: 2167-9843
• DOI: 10.7287/peerj.preprints.1461v1

The experiment was performed to determine the effects of alfalfa saponin extract (ASE) on the performance and cholesterol metabolism of laying hens. A total of 150 Hy-Line Brown hens with 28 weeks old, were randomly divided into five treatment groups (five replicates per treatment with six hens per replicate). Diets containing 0, 60, 120, 240, and 480 mg ASE/kg were fed to hens for 77 days. The shell thickness had a trend to increase. The yolk cholesterol and liver bile acid decreased significantly (ASE 60 and 480 mg/kg groups for yolk cholesterol, and ASE 60 and 240 mg/kg groups for liver bile acid). Fecal bile acid has an elevation trend as ASE increased. The expression of very low density apolipoprotein-Ⅱ (apoVLDL-Ⅱ) gene was not affected by adding ASE. However, the mRNA expression of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase gene and cholesterol 7α-hydroxylase (CYP7A1) gene were significantly up-regulated. The mRNA expression of very-low-density-lipoprotein receptor(VLDLR) gene was suppressed due to adding ASE supplementation in the diet. These findings indicated that dietary ASE could regulate cholesterol levels in hens by up-regulating the mRNA levels of HMG-CoA and CYP7A1 and suppressing the expression of VLDLR.