A Comparative Study On The Expression And Related Traits Of Lipid Metabolism Regulation Genes And Its Products Between Xinjiang Brown Cattle And Angus Cattle

Xinjiang brown cattle(XJBC)bred of ternary hybrid cattle which is a good local breed in China,XJBC and its high generation hybrid are the main varieties of XJBC breeding industry.However,its molecular mechanisms and development of fat metabolism related meat quantity traits are lack of clear invesitigation in comparison with those of excellent domestic and foreign breeds.Therefore,in this research,we chose XJBC at 7 months and 12 months as subjects,objective its that lipid metabolism regulates key genes in growth and development,and compare with Angus cattle(AG),in order to explore the origin of the fat metabolism related meat quality of XJBC.We choses 5 XJBC and AG at 3 months(weaning)which was carried out under the same breeding environment and feeding conditions,at 7 months and 12 months,comparative the carcass traits,the serum fat metabolic controlling hormones(fatty acid syntheses,fatty acid-binding protein 4,hormone-sensitive lipase,lipoprotein lipase and leptin)and the expression of m RNA(FASN,FABP4,HSL,LPL and Leptin)and adipose tissue morphology in the longest muscle and adipose tissue of the two species were compared by living sampling technique.The main results are as followings:1.Blood physiological,biochemical indexes and carcass indicators were compared in both of XJBC and AG: The number of leukocytes,granulocytes,and platelet macrocytes decreased significantly with age(P<0.001),and total number of red blood cells,the total number of platelets,the average volume of red blood cells and the platelet volume increased significantly with age(P<0.01).Creatinine,blood nitrogen uric acid,cholesterol,phosphorus,total bilirubin increased significantly with age(P<0.01),alkaline phosphatase and alanine transferase increased with age(P<0.01).A comparison of hormone levels:except FABP4,Leptin,FASN,HSL and LPL serum hormone levels all increased significantly with age(P<0.01).Five carcass indicators are shown in both of XJBC and BC: In addition to back fat thickness,eye muscle area,eye muscle thickness,intermuscular fat thickness,and live weight all increase significantly with age(P<0.01).2.Morphology comparison of fat cells in both of XJBC and AG: The cell area and the number of cells decreased significantly with age in peritoneal lipids(P<0.001),In subcutaneous fat,cell area decreases with age(P<0.001),and cell number increases with age(P<0.05).3.RT-PCR detection results in both of XJBC and AG: expression levels of Leptin m RNA in the longest back muscle were significantly increased with the increase of age(P<0.05),and HSL m RNA levels were significantly decreased with increasing age(P<0.01),LPL m RNA levels were significantly decreased with increasing age(P<0.01).Expression of Leptin m RNA in the week of renal lipid levels were significantly increased with the increase of age(P<0.05),HSL m RNA expression levels were significantly reduced with the increase of age(P<0.05),and LPL m RNA levels were significantly decreased with increasing age(P<0.001).Subcutaneous fat: The m RNA expression of FAS gene in XJBC of 12 months was significantly lower than that AG of 12 months(P<0.01).The m RNA expression of FABP4 gene XJBC of 12 months was lower than that AG of 12 months(P<0.05).The above results showed that the blood physiological and biochemical indexes and FASN,FABP4,HSL,LPL,and Leptin hormones contents of 7-month-old and 12-month-old XJBC and AG were different,and the slaughter traits and the adipose tissue cell area at different sites were different in Leptin.Genes such as FASN,FABP4,HSL,and LPL all showed differences in perirenal fat,subcutaneous fat,and longissimus dorsi muscle.These differences show the changes in the epigenetic and molecular mechanisms of XJBC and AG at the growth stage,which provide reference for the regulation of the meat quality of XJBC in the future.