饲粮粗蛋白质和粗脂肪水平对生长期貉生长性能、血清生化指标及游离氨基酸含量的影响

Effects of Dietary Crude Protein and Ether Extract Levels on Growth Performance,Serum Biochemical Indices and Free Amino Acid Contents of Raccoon Dogs during Growing Period

本试验旨在确定生长期貉饲粮中适宜的粗蛋白质和粗脂肪水平,为生长期貉饲粮配制提供科学依据。采用3×3完全随机设计,设定3个粗蛋白质水平分别为22%、24%和26%,3个粗脂肪水平分别为7.5%、9.5%和11.5%,共配制9种试验饲粮。所有饲粮中赖氨酸、含硫氨基酸和苏氨酸含量相等。选取体重相近的11周龄健康公貉63只,随机分为9组,每组7只,单笼饲养,试验期56 d。结果表明:1)饲粮粗脂肪水平显著影响末重、平均日增重和料重比(P <0.05),其中粗脂肪水平为9. 5%和11. 5%组的平均日增重显著高于粗脂肪水平为7. 5%组(P <0.05),料重比则随粗脂肪水平的升高而显著降低(P <0.05)。2)血清葡萄糖含量受饲粮粗脂肪水平的显著影响(P<0.05),且随粗脂肪水平的升高而显著降低(P<0.05);血清尿素氮含量受饲粮粗蛋白质水平的显著影响(P<0.05),其中粗蛋白质水平为26%组显著高于粗蛋白质水平为22%和24%组(P<0.05),粗蛋白质水平为22%和24%组间差异不显著(P> 0.05);此外,血清葡萄糖含量有随饲粮粗蛋白质水平的升高而增加的趋势(P=0.055)。3)血清游离赖氨酸、蛋氨酸、苏氨酸、总必需氨基酸、总非必需氨基酸及总氨基酸含量均受饲粮粗蛋白质与粗脂肪水平交互作用的显著影响(P<0.05),其中以饲粮粗蛋白质水平为24%、粗脂肪水平为7.5%时以及粗蛋白质水平为22%、粗脂肪水平为9.5%时所测各项指标的数值较高。上述结果提示,在平衡饲粮中赖氨酸、含硫氨基酸和苏氨酸含量的前提下,饲粮粗蛋白质水平为22%、粗脂肪水平为9.5%时生长期貉即可获得较好的生长性能。

This experiment was conducted to determine the optimal dietary crude protein(CP)and ether extract(EE)levels for raccoon dogs during growing period,so as to provide scientific basis for diet formulation.A 3×3 completely random design was adopted,and 9 experimental diets were prepared with 3 CP levels(22%,24%and 36%)and 3 EE levels(7.5%,9.5%and 11.5%).All diets contained the same contents of lysine,sulfur-containing amino acids and threonine.Sixty-three 11-week-old male raccoon dogs were randomly divided into 9 groups with 7 raccoon dogs per group,and the raccoon dogs were feed separately.The experiment lasted for 56 days.The results showed as follows:1)the final body weight,average daily gain(ADG)and feed/gain(F/G)of raccoon dogs were significantly affected by dietary EE level(P<0.05),and the raccoon dogs fed diets containing 9.5%and 11.5%of EE had significantly higher ADG than those fed diets with 7.5%of EE(P<0.05),while the F/G significantly decreased with the increase of dietary EE level(P<0.05).2)The serum glucose content of raccoon dogs was significantly affected by dietary EE level(P<0.05),and it was significantly decreased with the increase of dietary EE level(P<0.05).The serum urea nitrogen content of raccoon dogs was significantly affected by dietary CP level(P<0.05),and the raccoon dogs fed diet containing 26%of CP had significantly higher serum urea nitrogen content than those fed diets containing 22%and 24%of CP(P<0.05),but no significant difference was found in serum urea nitrogen content between the raccoon dogs fed diets containing 24%and 22%of CP(P >0.05).The serum glucose content had the tendency to increase with the dietary CP level increasing(P=0.055).3)The contents of serum free lysine,methionine,threonine,total essential amino acids,total nonessential amino acids and total amino acids were significantly affected by the interaction between dietary CP and EE levels(P<0.05),in which all above measured indices were higher when raccoon dogs fed diets with either 24%of CP and 7.5%of EE or 22%of CP and 9.5%of EE.The results suggest that raccoon dogs can have the better growth performance when the diet containing 22%of CP and 9.5%of EE during growing period under the precondition of balancing the contents of dietary lysine,sulfur-containing amino acids and threonine.