Effects of different levels of protein supplementary diet on gene expressions related to intramuscular deposition in early-weaned yaks.
This study was conducted to estimate different levels of protein supplementary diet on gene expressions related to intramuscular deposition in early-weaned yaks. Results showed that supplementary dietary protein significantly increased final weight, average daily gain (ADG), intramuscular fat (IMF), serum free fatty acid (FFA), total triglycerides, total cholesterol (Ch), low-density lipoprotein cholesterol (LDL) and high-density lipoprotein cholesterol (HDL) content. There was a quadratic response of ADG, IMF, FFA, Ch, HDL and LDL to dietary crude protein (CP) level. Lipoprotein lipase (LPL), fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC) enzyme activities were significantly increased by supplementary dietary CP, while hormone-sensitive lipase (HSL) and carnitine palmitoyltransferase-1 (CPT-1) activities were significantly decreased. LPL, ACC and FAS enzyme activities showed quadratic increase as dietary CP increased. Peroxisome proliferator-activated receptor γ (PPARγ), LPL, FAS, sterol regulatory element binding protein 1 (SREBP-1), ACC, stearoyl-CoA desaturase (SCD) and heart fatty-acid binding protein (H-FABP) gene expression were significantly increased by supplementary dietary CP, while HSL and CPT-1 gene expression were significantly decreased. PPARγ, LPL, SREBP-1, ACC and H-FABP gene expression showed quadratic increase as dietary CP increased. These results indicated that supplementary dietary protein increased IMF accumulation mainly to increased intramuscular lipogenic gene expression and decreased lipolytic gene expression.
Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Animal Nutrition Institute of Sichuan Agricultural University, Ya'an, China.
Hai-Bo
HB
Zhang
Zhi Sheng
ZS
Wang
Quan-Hui
QH
Peng
Cui
C
Tan
Hua-Wei
HW
Zou
D000103:Acetyl-CoA Carboxylase / Q000235:genetics / Q000378:metabolism; D000273:Adipose Tissue / Q000378:metabolism*; D000821:Animal Feed; D000824:Animal Nutritional Physiological Phenomena / Q000235:genetics* / Q000502:physiology; D000818:Animals; D002417:Cattle / Q000235:genetics* / Q000378:metabolism*; D004044:Dietary Proteins / Q000008:administration & dosage*; D019587:Dietary Supplements; D064429:Fatty Acid Synthases / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D050356:Lipid Metabolism / Q000235:genetics*; D050155:Lipogenesis / Q000235:genetics*; D008066:Lipolysis / Q000235:genetics; D008071:Lipoprotein Lipase / Q000235:genetics / Q000378:metabolism; D009132:Muscles / Q000378:metabolism*; D047495:PPAR gamma / Q000235:genetics / Q000378:metabolism; D051780:Sterol Regulatory Element Binding Protein 1 / Q000235:genetics / Q000378:metabolism
D004044:Dietary Proteins; D047495:PPAR gamma; D051780:Sterol Regulatory Element Binding Protein 1; D064429:Fatty Acid Synthases; D008071:Lipoprotein Lipase; D000103:Acetyl-CoA Carboxylase
dietary protein level; intramuscular fat; supplementary feeding; yak