Effects Of Dietary Grape Seed Ratio On Growth Performance,Slaughter Performance And Meat Quality Of Duolang Sheep

The lack of forage resources in southern Xinjiang is the key problem restricting the production of mutton sheep.In order to alleviate the adverse impact of forage shortage on meat sheep breeding industry in southern Xinjiang and improve the reuse of grape by-products and wastes,grape seeds in different proportions were added to the diet of Duolang sheep and made into a full price diet.The effects of grape seeds in different proportions on the growth performance,slaughtering performance,meat quality and blood index of Duolang sheep were studied through feeding test,slaughtering test,meat quality evaluation and blood index determination,The purpose is to provide data support for the scientific application of grape seed in mutton sheep breeding and provide scientific basis for the rational development of grape seed resources.Test 1: five different proportions of grape seed full price diets(0,4%,8%,12%,16%)were prepared.Twenty five(18.26 ± 2.65 kg)Duolang male lambs were randomly divided into five groups with five in each group and one repetition for each sheep.After the feeding test,calculate the final weight(FBW),average daily gain(ADG),dry matter intake(DMI),feed to weight ratio(f/g)and other indicators of each group.The results showed that there was no significant difference in average daily gain and feed intake(P>0.05)with the increase of the proportion of grape seeds in the diet,but the feed to weight ratio of 0 to 12% group showed a downward trend.The feed weight ratio of the 12% addition group was 2.04% lower than that of the control group.Conclusion: the growth performance of Duolang sheep fed with 12% grape seed was the best.Test 2: the test design is the same as that of test 1.After the feeding test,the slaughter test was conducted and the data were recorded.The results showed that there was no significant difference in carcass net meat weight among the groups(P>0.05),and the control group was the highest(10.33 kg);The slaughtering rate in the 4% addition group was the highest(49.70%),2.47%higher than that in the control group,which was significantly higher than that in the 0,8,12% and16% groups(P<0.05);The bone weight of 12% addition group was the highest(5.39 kg),and that of the control group was the lowest(4.51 kg).The bone weight of 12% addition group was significantly higher than that of the control group;The ratio of meat to bone was the highest in the control group(2.28),the lowest in the 16% addition group(1.86),and significantly higher in the control group than in the12% and 16% addition groups(P<0.05).There was no significant difference in rumen,reticulum and omasum weight among the groups(P>0.05);The proportion of rumen to pre-mortem live weight in the control group was significantly higher than that in the four experimental groups(P;There was no significant difference in the proportion of reticulum to pre-mortem live weight and total weight of compound stomach(P>0.05).The proportion of flap stomach to total weight of compound stomach in 8% and 12% addition group was significantly higher than that in 4%addition group(P<0.05);The weight of abomasum and its proportion to the total weight of compound stomach were the highest in the control group and the 16% addition group.Therefore,it is considered that the proportion of grape seed addition has no significant effect on the slaughtering performance of Duolang sheep,but it will reduce the growth and development speed of compound stomach.Test 3: the test design is the same as test 1.During the slaughter test,the left eye muscle,the right eye muscle and the biceps femoris muscle were taken,and the intramuscular fat and sarcolemma were finely removed to determine the meat color,ph24 h,water loss rate,cooked meat rate and shear force.The results showed that the color brightness and yellowness of left eye muscle,right eye muscle and biceps femoris muscle decreased first and then increased with the increase of grape seed addition ratio,and the redness increased first and then decreased.There was no significant difference in the water loss rate among the groups,but the water loss rate decreased slightly with the increase of grape seed content in the diet;The shear force of the control group with 4% addition was the highest;There was no significant difference in ph24 h of mutton among the groups with grape seed addition ratio;The ph24 h of mutton in the control group was the lowest(5.33),which was significantly lower than that in the other groups(P<0.05).Conclusion:when the content of grape seed in the feed was 8%～12%,the overall brightness and yellowness were lower,the redness was higher,and the flesh color was ruddy;The water loss rate and cooked meat rate decreased slightly;The addition of grape seed at 8%～16% shear force decreased significantly;There was no significant change in fresh meat p H,and ph24 h increased significantly after adding grape seeds to the diet.According to meat color,water loss rate,shear force,fresh meat p H,ph24 h and other meat quality indicators,the appropriate amount of grape seeds in the diet is 8%～12%.Test 4: the test design is the same as test 1.Blood samples were collected from sheep before morning feeding on the 1st,30 th and 60 th day of feeding experiment.The results showed that the total protein in the blood of Duolang sheep was increased after adding a certain proportion of grape seeds in the diet.The total protein in the 12% and 16% groups was significantly higher than that in the control group(P<0.05);Triglyceride in the 4% group was significantly higher than that in the other groups(P<0.05),creatinine in the 12% and 16% groups was significantly higher than that in the control group(P<0.05),and there was no significant difference in urea nitrogen content among the groups(P>0.05);Glutamic oxaloacetic transaminase in 16% addition group was significantly higher than that in control group,The total superoxide dismutase in 16% addition group was significantly higher than that in control group and 4% addition group(P<0.05).Conclusion: Based on the above results of blood physical and chemical indexes,it is appropriate to add 8%～12% to the diet of Duolang sheep.The comprehensive analysis showed that the production performance,slaughtering performance,organ index and blood index of Duolang sheep would be affected in varying degrees after adding different proportions of grape seeds in the diet.The optimal proportion of grape seeds in the diet of Duolang sheep was 8%～12%.