日粮中添加杜仲叶对育肥肉牛生长性能、消化率和胴体品质的影响

Effects of Eucommia ulmoides Leaves on Growth Performance,Digestibility and Carcass Quality of Beef Cattle

试验旨在研究日粮中杜仲叶添加量对育肥肉牛生长性能、屠宰性能、养分消化率和肉品质的影响。选取75头初始体重为(252.67±6.00)kg的本地黄牛×西门塔尔杂交公牛,采用随机区组试验设计分为5个处理组(1个对照组、4个试验组),每个处理组3个重复,每个重复5头牛,试验期150 d。4个试验组分别在基础日粮中添加1%、2%、3%和4%的杜仲叶以替代基础日粮中的粗料。结果表明:①添加杜仲叶对育肥肉牛的日增重、眼肌面积和日粮养分[粗蛋白(CP)、粗脂肪(EE)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)、钙(Ca)和磷(P)]表观消化率无显著影响(P>0.05),但屠宰率随杜仲叶添加量的增加呈二次曲线上升趋势,以3%添加组最高(P<0.05);②添加杜仲叶对肉牛背肌中CP和氨基酸含量、滴水损失、蒸煮损失、pH、嫩度、肉色无显著影响(P>0.05),但EE含量呈二次曲线下降,以3%组最低,比对照组低56.85%;③3%组的γ-亚麻酸(0.83%)较高,比对照组高93.02%,数值上多不饱和脂肪酸总和(13.58%)最高,比对照组高51.39%。在本试验条件下,日粮中添加杜仲叶具有提高肉牛屠宰率、降低肌肉脂肪含量,改善肌肉脂肪酸组成的作用,适宜添加量为3%。

This study aims to investigate the effect of the amount of Eucommia ulmoides leaf supplementation in the diet on the growth performance,slaughter performance,nutrient digestibility and meat quality of beef cattle.A total of 75 local yellow cattle×Simmental hybrid steers weighting (252.67±6.00) kg were randomly assigned to five treatments (0,1%,2%,3%and 4%Eucommia ulmoides leaf supplementation),then each treatment group had three replicates and five steers per replicate,and the test period was 150 days.The results showed that (1) Eucommia ulmoides leaves supplementation had no significant effect on daily gain,eye muscle area and apparent digestibility of nutrients (CP,EE,NDF,ADF,Ca and P)(P>0.05);but the slaughter rate increased with the increase of Eucommia ulmoides leaves,quadratical-ly,and the 3%group was the highest.(2) The Eucommia ulmoides supplementation had no significant effect on the crude protein and amino acids concentration,dripping loss,cooking loss,p H value,tenderness and meat color (P>0.05) in muscle;but the ether extract concentration decreased quadratically,the lowest was in the 3% group,56.85%lower than that in the control group.(3) 3% Eucommia ulmoides supplementation had higherγ-Linolenic acid (0.83%) in muscle than the other groups(P<0.05),and 93.02%higher than that in the control group;and the sum of polyunsaturated fatty acids(13.58%) was the highest,51.39%higher than that in the control group.Under the experimental conditions,Eucommia ulmoides leaves supplementation in the diet could improve the slaughter rate of beef cattle,decrease the content of muscle fat and improve the composition of muscle fatty acids.The appropriate dose was 3%.