紫花苜蓿对杜长大生长肥育猪生长性能及胴体品质的影响

为研究紫花苜蓿鲜草对生长肥育猪生长性能和胴体品质的影响，选择体重60 kg左右健康的杜长大生长肥育猪60头，采用完全随机化设计分为4个处理，每个处理3个重复，每个重复5头猪，对照组不饲喂紫花苜蓿鲜草，3个试验组分别在饲粮中添加10％、15％、20％紫花苜蓿鲜草。结果表明，试验各组间的均增重和日增重差异不显著（P〉0.05）；料重比随着紫花苜蓿鲜草添加量的增加而增大，其中20％紫花苜蓿组显著高于10％紫花苜蓿组（P＜0.05）；每千克增重所需饲料成本，10％、15％、20％紫花苜蓿组分别比对照组降低13.43％、12.21％、14.24％。干物质消化率随着紫花苜蓿鲜草添加量的增加而降低，20％紫花苜蓿组极显著低于对照组（P＜0.01）；粗蛋白质消化率随着紫花苜蓿鲜草添加量的增加而降低，对照组最高，极显著高于3个试验组（P＜0.01）；粗纤维消化率随着紫花苜蓿鲜草添加量的增加而提高，以20％紫花苜蓿组最高，极显著高于对照组和10％紫花苜蓿组（P＜0.01）。血清总蛋白、血糖、总胆固醇、甘油三酯、高密度脂蛋白4组间差异不显著（P＞0.05）；血清尿素氮，对照组与10％紫花苜蓿组、20％紫花苜蓿组间差异不显著（P＞0.05），但显著高于15％紫花苜蓿组（P＜0.05）；3个试验组间差异不显著（P＞0.05）。屠宰率、皮率、骨率、3点平均背膘厚、6～7肋背膘厚、眼肌面积、皮厚、胴体斜长、胴体直长及前、中、后躯占胴体重，各组间差异不显著（P＞0.05）；瘦肉率，3个试验组高于对照组，但差异不显著（P＞0.05）；肥肉率，3个试验组低于对照组，但差异不显著（P＞0.05）。小肠长和小肠重、大肠长和大肠重、肾重、心重、肺重、膀胱重，各组间差异不显著（P＞0.05）；胃重，3个试验组间差异不显著（P＞0.05），但均高于对照组，其中10％紫花苜蓿组、20％紫花苜蓿组显著高于对照组（P＜0.05）；肝重，3个试验组间差异不显著（P＞0.05），但均显著低于对照组（P＜0.05）。肉色、大理石纹、熟肉率、失水率、滴水损失及pH1、pH2各组间差异不显著（P＞0.05）。背最长肌粗蛋白质，3个试验组间差异不显著（P＞0.05），但均高于对照组，其中10％紫花苜蓿组显著高于对照组（P＜0.05）；粗脂肪、水分、干物质各组间差异不显著（P＞0.05）。结果显示，生长肥育猪饲粮中添加不同比例紫花苜蓿鲜草促进了生长肥育猪增重、降低了饲料成本，对血液理化指标无不良影响，不同程度地降低了背膘厚、提高了瘦肉率，改善了胴体品质。在本试验条件下，推荐紫花苜蓿鲜草适宜添加比例为15％。

Effect of Alfalfa on the Growth Performance and Carcass Quality of DLY Growing-finishing Pigs

This experiment was to study the effect of alfalfa grass on the growth performance and carcass quality of growing-finishing pigs.Sixty healthy growing-finishing pigs with the same height of 60 kg were randomly allo-cated to 4 treatments with 3 replicates of 5 pigs per replicate.The control group was not fed with the alfalfa grass,while 10%,15% and 20% proportion of alfalfa grass were added in the diet of the pigs in 3 experimental groups,respectively.Results showed that there was no significant difference in average gain and average daily gain between the experimental groups（P〉0.05）.With the increasing of the proportion of alfalfa grass,the feed con-version ratio increased,and the 20% proportion of alfalfa grass group was significant higher thanthe 10% propor-tion of alfalfa grass group （P〈0.05）.The feed costs per kilogram weight of the 10%,15%,20% proportion of alfalfa grass groups decreased 13.43%,12.21%and 14.24%than the control group,respectively.With the adding propor-tion increasing,the dry matter digestibility decreased,the 20% proportion of alfalfa grass group was extremely sig-nificant lower than the control group（P〈0.01）.With the adding proportion increasing,the crude protein digestibility decreased,the control group was the highest,and was extremely significant higher than the 3 experimental groups （P〈0.01）.With the adding proportion increasing,the crude fiber digestibility rate increased,the 20% proportion of alfalfa grass group was the highest,and was extremely significant higher than the control group and the 10% pro-portion of alfalfa grass group （P〈0.01）.There was no significant difference in serum total protein,blood glucose,to-tal cholesterol,triglycerides and high-density lipoprotein cholesterol between the four groups （P〉0.05）.There was no significant difference in serum urea nitrogen between the control group and the 10% and 20% proportion of alfalfa grass groups （P〉0.05）,but the control group was significant higher than the 15% proportion of alfalfa grass group （P〈0.05）,and there was no significant difference between the 3 experimental groups （P〉0.05）.There was no significant difference in dressing percentage,skin rate,rate of bone,average backfatthickness,backfatthickness of 6~7 rib,eye muscle area,thickness of skin,body length,body straight length and before,middle and behind body of carcass weight between groups （P〉0.05）.Lean meat rate of 3 experimental groups were higher than that of the control group,but there was no significant difference （P〉0.05）.Fat meat rate of 3 experimental groups were lower than that of the control group,but there was no significant difference （P〉0.05）.There was no significant difference inthe length and weight of small intestine,the length and weight of large intestine,the weight of kidney,heart,lung and bladder between groups（P〉0.05）.There was no significant difference instomach weight between 3 experimen-tal groups （P〉0.05）,but they were greater than the control group,and the 10% and 20% proportion of alfalfa grass groupwere significant higher than the control group （P〈0.05）.There were no significant difference in liver weight between the 3 experimental groups（P〉0.05）,but they were significant lower than the control group（P〈0.05）.There was no significant difference in the color of the meat,marble,cooked meat rate,water loss rate,water loss and pH1, pH2 between groups（P〉0.05）.There were no significant difference in the crude protein of longest back muscle be-tween 3 experimental groups （P〉0.05）,but they were higher than the control group,and the 10% proportion of al-falfa grass groupwere significant higher than the control group （P〈0.05）.There were no significant difference in-crude fat,moisture,dry matter between groups（P〉0.05）.The results showed that growing-finishing pigs diet adding different proportion of alfalfa grass,improved the growing-finishing pigs weight,decreased the feed cost and had no adverse effect on the physical and chemical indices,and partlyreduced back fat thickness,improved the lean meat rate and the carcass quality.Under this experimental condition,the alfalfa grass alternative diet appropriate adding ratio was 15%.