包膜赖氨酸对稚鳖生长性能的影响及机理探讨

Effects of coated lysine on growth performance in juvenile soft shell turtles and discuss on its mechanism

试验选择平均体重为18.40 g稚鳖180只,分为3组(每组6个重复,每重复10只),分别饲喂赖氨酸缺乏的(赖氨酸水平1.51%),添加晶体赖氨酸和包膜赖氨酸(赖氨酸水平均为2.62%)等能等氮半合成饵料,试验期60d。结果表明,赖氨酸缺乏组鳖晒背率、惊吓逃跑率、特定生长率、肝脏赖氨酸-α-酮戊二酸还原酶活性较低,腐斑率和饵料系数高。添加包膜赖氨酸显著提高了鳖生活力,特定生长率和蛋白质效率,且作用效果优于晶体赖氨酸。赖氨酸缺乏组和晶体赖氨酸组鳖摄食后6 h内血清游离赖氨酸在2 h左右达到高峰水平,而包膜赖氨酸组在4 h左右达到高峰水平。说明包膜赖氨酸可延缓血清游离赖氨酸达到高峰浓度的时间,促进氨基酸的有效利用和蛋白质的合成。

A total of 180 juvenile soft shell turtles（average initial body weight 18.40 g）were used to study the effects of coated lysine on growth performance.The turtles were randomly allocated to three groups with six replicates each group, which were fed isonitrogenous and isoenergetie semisynthetic diets containing different lysine levels （1.51%,2.62 % in the form of lysine hydroehloride or coated lysine hydrochloride） for a period of 60.The results showed that sunshine rate, flee rate, specific growth rate,]Liver lysine-a-ketoglutarate reductase activity in lysine deficiency group were lower and skin rot rate and feed coefficient were higher.Dietary coated lysine supplementation had a significant effect on living ability, specific growth rate and protein efficiency ratio.The highest level of serum free lysine occurred at 2 h after fed in lysine deficiency group and lysine hydrochloride group,while at 4 h in coated lysine group.The results indicated that the time of the highest level of serum free lysine was delayed in coated lysine group and the effective utilization of amino acids and protein synthesis were promoted.