title: Feeding a High Concentrate Diet Down-Regulates Expression of ACACA, LPL and SCD and Modifies Milk Composition in Lactating Goats.
abstract: High concentrate diets are fed to early and mid-lactation stages dairy ruminants to meet the energy demands for high milk production in modern milk industry. The present study evaluated the effects of a high concentrate diet on milk fat and milk composition, especially, cis-9, trans-11 CLA content in milk and gene expression of lactating goats. Eight mid-lactating goats with rumen fistula were randomly assigned into a high concentrate diet (HCD) group and low concentrate diet (LCD) group. High concentrate diet feeding significantly increased lipopolysaccharides (LPS) in plasma and decreased milk fat content, vaccenic acid (VA) and cis-9, trans-11 CLA in milk of the lactating goats. The mRNA expression levels of sterol regulatory element binding protein B 1c (SREBP1c), lipoprotein lipase (LPL), fatty acid synthetase (FASN) and acetyl-CoA carboxylase α (ACACA, ACCα) involving in lipid metabolism were analyzed, and ACACA and LPL all decreased in their expression level in the mammary glands of goats fed a high concentrate diet. DNA methylation rate of stearoyl-CoA desaturase (SCD) was elevated and decreased, and SCD mRNA and protein expression was reduced significantly in the mammary glands of goats fed a high concentrate diet. In conclusion, feeding a high concentrate diet to lactating goats decreases milk fat and reduced expression of SCD in the mammary gland, which finally induced cis-9, trans-11 CLA content in milk.
authors.affiliation: College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Tao
authors.affiliation: College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China.
authors.forename: Guangjun
authors.initials: G
authors.lastname: Chang
authors.affiliation: College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China.
authors.forename: Tianle
authors.initials: T
authors.lastname: Xu
authors.affiliation: College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China.
authors.forename: Huajian
authors.initials: H
authors.lastname: Zhao
authors.affiliation: College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Zhang
authors.affiliation: College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China.
authors.forename: Xiangzhen
authors.initials: X
authors.lastname: Shen
mesh_terms: D000103:Acetyl-CoA Carboxylase / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D019175:DNA Methylation; D004032:Diet / Q000662:veterinary*; D015536:Down-Regulation; D064429:Fatty Acid Synthases / Q000235:genetics / Q000378:metabolism; D005227:Fatty Acids / Q000032:analysis; D005260:Female; D006041:Goats; D007536:Isomerism; D007774:Lactation; D044243:Linoleic Acids, Conjugated / Q000378:metabolism; D008070:Lipopolysaccharides / Q000097:blood; D008071:Lipoprotein Lipase / Q000235:genetics / Q000378:metabolism*; D008321:Mammary Glands, Animal / Q000378:metabolism; D008892:Milk / Q000378:metabolism*; D009829:Oleic Acids / Q000378:metabolism; D012417:Rumen / Q000378:metabolism; D013230:Stearoyl-CoA Desaturase / Q000235:genetics / Q000378:metabolism*; D051780:Sterol Regulatory Element Binding Protein 1 / Q000235:genetics / Q000378:metabolism
chemical_list: D005227:Fatty Acids; D044243:Linoleic Acids, Conjugated; D008070:Lipopolysaccharides; D009829:Oleic Acids; D051780:Sterol Regulatory Element Binding Protein 1; D013230:Stearoyl-CoA Desaturase; D064429:Fatty Acid Synthases; D008071:Lipoprotein Lipase; D000103:Acetyl-CoA Carboxylase; C050413:11-octadecenoic acid