饲料中过量添加晶体蛋氨酸和蛋氨酸羟基类似物对大菱鲆生长、饲料利用和抗氧化反应的影响

以初始体质量为(5.49±0.01)g的大菱鲆幼鱼为实验对象,探讨饲料中过量添加晶体蛋氨酸或蛋氨酸羟基类似物对大菱鲆生长、饲料利用和抗氧化反应的影响.以白鱼粉和豆粕为主要蛋白源,饲料中同时添加0.25％ DL-蛋氨酸和0.3％蛋氨酸羟基类似物钙盐(MHA)作为对照,在此基础上分别添加0.5％ DL-蛋氨酸、1.25％ DL-蛋氨酸、0.59％MHA、1.49％ MHA、1.25％ DL-蛋氨酸+0.85％柠檬酸钙,配制出6种实验饲料,使饲料中蛋氨酸和蛋氨酸羟基类似物(HMTBA)含量分别是1.35％、1.83％、2.50％、1.45％、1.37％、2.51％和0.22％、0.22％、0.22％、0.63％、1.38％、0.29％.养殖试验在室内流水系统中进行,持续10周,每个处理设5个重复,每个重复放养大菱鲆幼鱼30尾.结果显示,过量添加DL-蛋氨酸和HMTBA对大菱鲆幼鱼生长无显著影响(P＞0.05).过量添加DL-蛋氨酸和HMTBA对大菱鲆体组分、肥满度(CF)、脏体比(VSI)和肝体比(HSI)均无显著影响(P＞0.05),但柠檬酸钙添加组(处理6)体蛋白含量与基础饲料组相比显著降低(P＜0.05).对大菱鲆肝脏过氧化氢酶( CAT)、超氧化物歧化酶(SOD)和肝脏硫代巴比妥酸反应产物量(TBARS)进行测定,各处理组间均无显著性差异(P＞0.05).结果显示,在该实验条件下,过量添加晶体蛋氨酸(1.31～1.73倍)和HMTBA(1.32～1.75倍)对大菱鲆幼鱼的生长、饲料利用和抗氧化反应没有显著影响.

The Influence of Overdose Dietary DL-Methionine or HMTBA on Growth, Feed Utilization and Anti-Oxidant Responses of Turbot (Scophthalmus maximus L.)

A growth experiment was conducted to evaluate the influence of overdose dietary DL-methionine(Met) or 2-Hydroxy-4-(Methylthio) butanoic acid(HMTBA) on turbot(initial body weight:(5.49±0.01) g).The control contained 1.35% Met and 0.22% HMTBA.Five different doses of Met or HMTBA were added to the basal diet,respectively.Finally,6 experimental diets were formulated,and the analyzed levels of Met or HMTBA in diets are as follows: Met: 1.35%,1.83%,2.50%,1.45%,1.37%,2.51%;HMTBA: 0.22%,0.22%,0.22%,0.63%,1.38% and 0.29%.Each diet was fed to five replicate groups of turbot for 10 weeks.Results showed that no significant differences in growth responses were found among dietary treatments(P>0.05).No significant difference was observed in body composition,condition factor(CF),visceral indexes(VSI),and hepatosomatic indexes(HSI)(P>0.05),but the content of body protein of fish in treatment of diet 6 was significantly lower than those in the control and diet 2(P<0.05).No significant differences in hepatic catalase activity,superoxide dismutase activity,thiobar-bituric acid reactive substances value were found in liver(P>0.05).In conclusion,overdose dietary DL-Met(1.31~1.73 times) or HMTBA(1.32~1.75 times) had no significant effects on growth,feed utilization and anti-oxidant responses in turbot under the current experimental conditions.