低蛋白质饲粮中添加DL-蛋氨酸和赖氨酸对冬毛期蓝狐生产性能、氮平衡及毛皮质量的影响(英文)

Effects of Low-protein,DL-methionine and Lysine-supplemented Diets on Growth Performance,N-balance and Fur Characteristics of Blue Foxes (Alopex lagopus) during the Growing-furring Period

本文旨在探讨低蛋白质饲粮中添加DL-蛋氨酸和赖氨酸对冬毛生长期蓝狐生长性能、氮平衡和毛皮质量的影响,并研究低蛋白质饲粮中蛋氨酸和赖氨酸的最适添加量。对照组饲粮蛋白质水平为27%(P27),低蛋白质饲粮蛋白质水平为19%(P19),选择健康的生长后期雄性蓝狐120只(17周龄左右),随机分成10组,每组12只。本试验采用3×3双因子交叉试验设计,有3个赖氨酸水平(0.3%、0.5%、0.7%)和3个含硫氨基酸水平(0.4%、0.6%、0.8%),试验组编号分别为P27、L1 M1、L1 M2、L1 M3、L2 M1、L2 M2、L2 M3、L3 M1、L3 M2和L3 M3,饲养试验试验期为61 d(2007-10-12～2007-12-12)。结果表明,如果考虑蓝狐平均日增重、日氮沉积、氮沉积率,0.6%的蛋氨酸水平最佳;如果考虑日氮沉积和毛皮质量,0.3%和0.5%的赖氨酸水平最佳;如果考虑氮的表观消化率、日粪氮排出量,0.3%的赖氨酸水平最佳;各处理蓝狐的毛皮质量与对照组差异不显著(P>0.05)。综合各项指标,L1 M2(0.3%Lys×0.6%Met)组蓝狐生产性能最佳;低蛋白质饲粮中添加蛋氨酸和赖氨酸不影响冬毛期蓝狐的生产性能;应用低蛋白质饲粮降低了排泄物中氮的含量,减轻了环境污染,节约了蛋白质资源。

An experiment was carried out to examine the effects of low-protein diets supplemented with different levels of DL-methionine（Met） and Lysine（Lys） on growth performance and fur characteristics of growing-furring blue foxes in order to find the optimal dietary supplementation levels of Met and Lys.For two protein levels,conventional 27%（P27） and low 19%（P19）,the measured protein contents of the diets were 271.2 and 189.4 g/kg on dry matter basis,respectively,and the low-protein diets were supplemented with Met（0.3%,0.5%,0.7%） and Lys（0.4%,0.6%,0.8%）.An entirely random experimental design was adopted with two factors（3×3） and totally 10 groups（P27,L1M1,L1M2,L1M3,L2M1,L2M2,L2M3,L3M1,L3M2 and L3M3）.From mid-September to pelting,based on the average daily gain,daily N retention,N retention ratio and the performance of blue foxes in different groups,0.6% Met supplementation in low-protein diet was optimum;based on the daily N retention,N biological value and the quality of the fur,0.3% and 0.5% Lys supplementation were optimum;based on the N apparent digestibility and daily N output,0.3% Lys supplementation was optimum.No significant differences were observed in fur characteristics of blue foxes in all groups（P0.05）.In this experiment,the performance of blue foxes in L1M2（0.3% Lys×0.6% Met） group was better than that in the other groups,which indicates that low-protein diets supplemented with DL-methionine and lysine for blue foxes can be beneficial to reduce feed expenses and nitrogen emission to the environment.