意大利蜜蜂工蜂幼虫饲粮的适宜赖氨酸水平

Dietary Appropriate Lysine Level for Apis mellifera ligustica Worker Bee Larvae

本试验旨在研究意大利蜜蜂工蜂幼虫饲粮的适宜赖氨酸水平,为探明意大利蜜蜂工蜂幼虫发育阶段的赖氨酸营养需要提供理论依据。选用1日龄意大利蜜蜂工蜂幼虫1 200只,随机分为5个组,每个组5个重复,每个重复48只。5组工蜂幼虫分别饲喂赖氨酸实测水平为6.08(对照)、11.08、16.08、21.08和26.08 mg/g的饲粮,饲养至幼蜂羽化出房。分别于特定日龄测定工蜂幼虫化蛹率(6日龄)、虫体总蛋白含量(6日龄)、羽化率(21日龄)等生长指标以及血淋巴生化指标和免疫相关指标(6日龄)。结果表明:1)11.08 mg/g赖氨酸组的工蜂幼虫化蛹率和羽化率极显著高于其他各组(P<0.01)。2)与对照组相比,11.08~26.08 mg/g赖氨酸组6日龄工蜂幼虫虫体总蛋白含量和血淋巴中游离赖氨酸含量显著提高(P<0.05),其中饲粮赖氨酸水平为26.08 mg/g时6日龄工蜂幼虫虫体总蛋白含量和血淋巴中游离赖氨酸含量最高。3)6日龄工蜂幼虫血淋巴中甘油三酯含量随饲粮赖氨酸水平的升高呈先下降后上升的趋势,其中饲粮赖氨酸水平为16.08 mg/g时处于最低值,极显著低于其他各组(P<0.01)。4)11.08~21.08 mg/g赖氨酸组6日龄工蜂幼虫血淋巴中溶菌酶活性显著高于对照组(P<0.05),但随着饲粮赖氨酸水平由21.08 mg/g升高到26.08 mg/g,6日龄工蜂幼虫血淋巴中溶菌酶活性急剧下降,26.08 mg/g赖氨酸组显著低于其他各组(P<0.05)。5)饲粮赖氨酸水平为11.08 mg/g时,6日龄工蜂幼虫虫体溶菌酶基因的相对表达量最高,显著高于其他赖氨酸水平时(P<0.05)。与对照组相比,11.08~16.08 mg/g赖氨酸组6日龄工蜂幼虫虫体防卫素1基因的相对表达量显著增加(P<0.05)。由此得出,赖氨酸能够促进意大利蜜蜂工蜂幼虫生长,促进蛋白质和赖氨酸的沉积,提高羽化率,并在一定程度上对脂质代谢和幼虫免疫能力产生调节作用;综合考虑上述指标,推荐意大利蜜蜂工蜂幼虫饲粮的适宜赖氨酸水平为11.08~16.08 mg/g。

The objective of this experiment w as to research the appropriate level of lysine in the diet for Apis mellifera ligustica w orker bee larvae,and to provide the theoretical basis for the study of lysine requirement of A pis mellifera ligustica w orker bee in larvae stage. A total of 1 200 one-day-old A pis mellifera ligustica w orker bee larvae w ere randomly divided into 5 groups w ith 5 replicates per group and 48 larvae per replicate. The w orker bee larvae in 5 groups w ere fed diets w ith the measured level of lysine w as 6. 08（ control）,11. 08,16.08,21. 08 and 26. 08 mg/g until emergence,respectively. The grow th indexes,such as pupation rate（ 6-day-old）,total protein content in whole body（ 6-day-old）,eclosion rate（ 21-day-old）,and the hemolymph biochemical parameters and immune related indicators（ 6-day-old） of w orker bee larvae w ere measured to certain age,respectively. The results show ed as follow s： 1） the pupation rate and eclosion rate of w orker bee larvae in 11. 08 mg/g lysine group w ere extremely significantly higher than those in other groups（ P〈0.01）. 2） Compared w ith the control group,the total protein content in w hole body and the free lysine content in hemolymph of 6-day-old w orker bee larvae in 11. 08 to 26. 08 mg/g lysine groups w ere significantly increased（ P〈0. 05）,and the highest values of them w ere found in 26. 08 mg/g lysine group. 3） The hemolymph triglyceride content of 6-day-old w orker bee larvae w as decreased firstly and then increased w ith dietary lysine level increasing,and the low est value w as found in 16.08 mg/g lysine group w hich w as extremely significantly low er than that in other groups（ P〈0.01）. 4） The haemolymph lysozyme activity of 6-day-old w orker bee larvae w as significantly higher than that of control group（ P〈0. 05）,but w ith dietary lysine level w as increased from 21. 08 to 26. 08 mg/g, the haemolymph lysozyme activity decreased rapidly, and it in26.08 mg/g lysine group w as significantly low er than that in other groups（ P〈0.01）. 5） When dietary lysine level w as 11.08 mg/g,the relative expression level of lysozyme gene of 6-day-old w orker bee larvae w as the highest,w hich w as significantly higher than that of the other lysine levels（ P〈0.05）. Compared w ith the control group,the relative expression level of defensin 1 gene of 6-day-old w orker bee larvae in 11. 08 to16.08 mg/g lysine groups w as significantly increased（ P〈0.05）. In conclusion,lysine can promote the grow th of Apis mellifera ligustica w orker bee larvae,promote the deposition of protein and lysine,increase the rate of eclosion,and regulate the lipid metabolism and the immunity of larvae to some extent. Based on the above indexes,it is recommended that the appropriate lysine level in the diet of Apis mellifera ligustica w orker bee larvae is 11.08 to 16.08 mg/g.