Comparative Analysis Of Fat Deposition And Quality Of Hulunbeier Sheep

In order to explore the fat deposition and quality comparative analysis of Hulunbeier sheep,the Longissimus dorsi(B),Triceps brachii(Q),and Biceps femoris(H)samples of 5-month-old Baerhu sheep(n = 10)and short-tailed sheep(n = 10)were collected for the measure of p H,color,shear force and cooking loss of the mutton.The fat and fatty acid composition in muscle samples were determined by the gas chromatography and near-infrared full grating transmission technology,respectively.The RNA expression of obesity gene(FTO)and methyltransferase Like3(METTL3)were analyzed by Real-Time PCR to study the difference of obesity-related gene expression in muscle tissue of Baerhu sheep and short-tailed sheep and its influence on intramuscular fat(IMF)deposition,and provide theoretical basis and data support for improving the meat quality of Baerhu sheep and short-tailed sheep.After studying the meet quality and fat deposition in Baerhu sheep and short-tailed sheep,the results showed that the tenderness of longissimus dorsi and cooking loss of Q of Baerhu sheep were significantly higher than those of short-tail sheep(P < 0.05).The proportions of polyunsaturated fatty acids in three muscle parts of short-tailed sheep were significantly higher than those of Baerhu sheep(P < 0.05).The expression of FTO and METTL3 gene in B and Q of Baerhu sheep was significantly higher than that of short-tailed sheep(P < 0.05),and the IMF of B and Q of short-tailed sheep was significantly higher than that of Baerhu sheep(P < 0.05).The above results indicate that the color and tenderness of Baerhu sheep are better,and the nutritional quality of short-tailed sheep is higher.Correlation analysis showed that the IMF content of H of Baerhu sheep and short-tailed sheep were significantly negatively correlated with their shear force,and the IMF of Q and H muscle were significantly negatively correlated with cooking loss rate(P<0.05).FTO expression level in H of Barghu sheep and short-tailed sheep was significantly positively correlated with IMF content(P < 0.05),and METTL3 expression level in Q and H of Baerhu sheep was significantly negatively correlated with IMF content(P < 0.05).In summary,FTO and METTL3 genes played positive and negative regulatory roles respectively in the IMF deposition of Baerhu sheep and short-tailed sheep,which may eventually lead to the difference in IMF deposition between Baerhu sheep and short-tailed sheep,thereby changing their meat quality.