饲料中添加二苯乙烯苷对斑点叉尾鮰生长和体色的影响

在饲料中分别添加0、0.33%、0.67%、1.33%和2.67%的二苯乙烯苷(THSG)制成5种等氮等能试验饲料饲喂(15±0.5)g斑点叉尾鮰(Ictalurus punctatus)42 d,研究THSG对其生长和体色的影响。结果表明。饲料中添加THSG对斑点叉尾鮰增重率和存活率均无显著影响,仅在添加量为2.67%时,试验组的饵料系数显著高于对照组(P<0.05);然而,随着添加量的增加,鮰皮肤和血液酪氨酸酶活力、皮肤黑色素含量和黑色素分布量均有提高,其中0.33%和0.67%组皮肤中酪氨酸酶活力分别为10.4 U和10.7 U,显著高于对照组的7.86 U;黑色素分布量分别为8.16%和9.38%,显著高于对照组的5.01%(P<0.05)。

Effects of dietary stilbene glucoside on growth and body color of Ictalurus punctatus

A 42 d feeding-trial was conducted to evaluate the effects of stilbene glucoside(tetrahydroxystilbene glucoside,THSG) on the growth and body color performance of Ictalurus punctatus.Five isonitrigenous diets were formulated to contain 36.6% protein and 7.3% lipid.THSG was added at four inclusion levels of 0.33%,0.67%,1.33% and 2.67%(diets A-D).The control diet didn’t contain THSG(diet Ctr).Weight gain(WG),Survival and feed conversion ratio(FCR) were not significantly affected when the THSG added except FCR,which presented statistical significance in diet D;In diets A-D,tyrosinase activity in blood and skin,melanin content and distribution in the skin were higher than the diet Ctr,and tyrosinase activity in skin of diet A and diet B is 10.4 ug/cm2 and 10.6 ug/cm2 respectively,melanin distribution is 8.16% and 9.38% respectively,which were significantly higher than that of 7.86 ug/cm2 and 5.01% in control(P<0.05).These results indicate that adding THSG to Channel catfish feed has obvious influence on body color and without adverse effect on growth performance.Based on the results of WG,FCR,survival,tyrosinase activity in blood and skin,melanin content and distribution,it was feasible to improve the body color by dietary stilbene glucoside.