全株玉米青贮中乳酸片球菌及其与尿素混合添加对杜泊绵羊生长性能、屠宰性能和肌肉品质的影响

Effects of Lactococcus lactococcus and It Mixed with Urea Added in Whole Corn Silage on Growth Performance,Slaughter Performance and Meat Quality of Dorper Sheep

本试验旨在研究全株玉米青贮中乳酸片球菌(Pediococcus acidilactici)及其与尿素混合添加对杜泊绵羊生长性能、屠宰性能和肌肉品质的影响,为全株玉米青贮在育肥羊上更好的利用以及肉质改良提供科学依据。试验选取60只体重[(23.0±1.5)kg]相近、健康状况良好的2月龄断奶杜泊绵羊公羊,随机分为3组,每组4个重复,每个重复5只羊。3组羊分别饲喂由不含任何添加剂的全株玉米青贮(对照组)、单一添加占全株玉米鲜重0.1%的乳酸片球菌的全株玉米青贮(益生菌组)和混合添加占全株玉米秸秆鲜重0.1%的乳酸片球菌与0.5%的尿素的全株玉米青贮(混合组)配制而成的全混合日粮。预试期10 d,正试期90 d。结果表明:1)混合组的终末体重和平均日增重显著高于对照组和益生菌组(P<0.05),混合组和益生菌组的料重比显著低于对照组(P<0.05)。2)混合组的胴体重、屠宰率、净肉率、肉骨比和GR值显著高于对照组(P<0.05),混合组的前活重显著高于对照组和益生菌组(P<0.05)。3)益生菌组的肌肉pH 24 h显著低于对照组(P<0.05);益生菌组和混合组的肌肉滴水损失和失水率显著低于对照组(P<0.05),熟肉率显著高于对照组(P<0.05)。4)益生菌和混合组的肌肉粗脂肪含量显著高于对照组(P<0.05),混合组的肌肉粗灰分含量显著高于益生菌组(P<0.05),混合组的肌肉赖氨酸、苯丙氨酸、缬氨酸、组氨酸和精氨酸含量显著高于益生菌组和对照组(P<0.05)。由此可见,饲喂在全株玉米青贮中单一添加乳酸片球菌的全混合日粮并不能改变杜泊绵羊的生长性能,而饲喂在全株玉米青贮中混合添加乳酸片球菌与尿素的全混合日粮能够提高杜泊绵羊的平均日增重,降低料重比,提高胴体重和屠宰率等,增加肌肉中粗脂肪和部分氨基酸含量,改善羊肉品质。

This experiment was conducted to study the effects of Lactococcus lactococcus and it mixed with urea added in whole corn silage on the growth performance,slaughter performance and meat quality of Dorper sheep,to provide scientific basis for better utilization of whole corn silage and meat quality improvement in fattening sheep. Sixty healthy 2-month-old weaned male Dorper sheep with similar body weight [( 23. 0 ±1.5) kg]were selected and randomly divided into 3 groups with 4 replicates per group and 5 sheep per replicate.Sheep were fed no additives whole corn silage( control group),single addition of 0.1% Lactococcus lactococcus of whole corn fresh weight( probiotics group) and 0.1% Lactococcus lactococcus mixed with 0.5%urea mixture of whole corn fresh weight( mixed group) formulated total mixed rations,respectively. The preexperimental period lasted for 10 days,and the experimental period lasted for 90 days. The results showed as follows: 1) the final body weight and average daily gain of mixed group were significantly higher than those of probiotics group and control group( P<0.05),and the feed to gain ratio of mixed group and probiotics group was significantly lower than that of the control group( P<0.05). 2) The carcass weight,dressing percentage,net meat ratio,meat to bone and GR value of mixed group were significantly higher than those of the control group( P<0.05),and the pre-slaughter weight of mixed group was significantly higher than that of probiotics group and control group( P<0.05). 3) The muscle pH24 h of probiotics group was significantly lower than that of the control group( P< 0.05);the drop loss and water loss ratio in muscle of mixed group and probiotics group were significantly lower than those of the control group( P<0.05),and the cooked meat ratio was significantly higher than that of the control group( P<0.05). 4) The muscle ether extract content of mixed group and probiotics group was significantly higher than that of the control group( P<0.05),and the contents of lysine,phenylalanine,valine,histidine and arginine in muscle of mixed group were significantly higher than those of probiotics group and control group( P<0.05). In conclusion,feeding the single addition of Lactococcus lactococcus in whole corn silage total mixed ration cannot change the growth performance of Dorper sheep,feeding the addition of Lactococcus lactococcus mixed with urea in whole corn silage total mixed ration can improve the growth performance,decrease the feed to gain ratio,improve the carcass weight and dressing percentage et al,and it can increase the contents of ether extract and some amino acids in muscle,improve the meat quality of sheep.