Effects of alfalfa saponin extract on the performance and cholesterol metabolism of laying hens
- Published
- Accepted
- Subject Areas
- Agricultural Science, Biochemistry, Molecular Biology, Zoology
- Keywords
- Chicken, Alfalfa saponin extract, Cholesterol metabolism, mRNA expression
- Copyright
- © 2015 Zhang et al.
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ PrePrints) and either DOI or URL of the article must be cited.
- Cite this article
- 2015. Effects of alfalfa saponin extract on the performance and cholesterol metabolism of laying hens. PeerJ PrePrints 3:e1461v1 https://doi.org/10.7287/peerj.preprints.1461v1
Abstract
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.
Author Comment
This is a preprint submission to PeerJ.
Supplemental Information
Figure 1. Effects of alfalfa saponin extract (ASE) on performance of egg weight, egg production, feed intake, and feed efficiency
Values are expressed as mean±SD (n = 5). Values with different small letters differ significantly (P < 0.05), while those with different capital letters differ very significantly (P < 0.01).
Figure 2. Effects of alfalfa saponin extract (ASE) on the performance of egg shape index, shell strength, shell thickness, Haugh unit, and yolk colour
Values are expressed as mean±SD (n = 80). Values with different small letters differ significantly (P < 0.05), while those with different capital letters differ very significantly (P < 0.01).
Figure 3. Effects of alfalfa saponin extract (ASE) on the concentration of yolk cholesterol, liver cholesterol, liver BA, and fecal BA
Values are expressed as mean±SD (n = 80 for yolk cholesterol; n = 5 for others). Values with different small letters differ significantly (P < 0.05), while those with different capital letters differ very significantly (P < 0.01).
Figure 4. Effects of alfalfa saponin extract (ASE) on the serum biochemical indices in laying hens
Values are expressed as mean±SD (n = 5). Values with different small letters differ significantly (P < 0.05), while those with different capital letters differ very significantly (P < 0.01). TC – total cholesterol; TG – total triglycerides; HDL-C – high density lipoproteins cholesterol; LDL-C – low density lipoproteins cholesterol; and VLDL-C – very low density lipoproteins cholesterol.
Figure 5. Effects of alfalfa saponin extract (ASE) on mRNA expression of cholesterol metabolism genes in liver and ovary of laying hens
(A), (C), and (D) were from liver while (B) was from ovary. n = 5. Different letters indicate significant difference (P < 0.05) using one-way ANOVA; HMGCR – HMG-CoA reductase.
