饲料中添加产油红酵母菌株PR61干菌体对红鲫鱼生长性能及体色的影响

Effect of oil-producing Rhodotorula strain PR61 in feed on growth performance and body color of red crucian carp

试验旨在研究产油红酵母菌株PR61干菌体作为鱼类饲料添加剂的剂量以及破壁处理对红鲫鱼饲喂效果的影响。选用平均体重4~5 g的红鲫鱼375条,随机分为5组,每组3个重复,每个重复25条鱼。空白对照组鱼饲喂100%基础饲料,阳性对照组鱼饲喂100%基础饲料+0.25%甜菜碱盐酸盐,T1组鱼饲喂99.5%基础饲料+0.5%未破壁红酵母,T2组鱼饲喂99.5%基础饲料+0.5%破壁红酵母,T3组鱼饲喂99%基础饲料+1%破壁红酵母。试验期28 d。结果显示,产油红酵母菌株PR61干菌体营养丰富,蛋白质含量高达45.2%,油脂含量高达38.93%,还含有类胡萝卜素及天门冬氨酸、丝氨酸等17种氨基酸,氨基酸总量为44.32%。T2组和T3组红鲫鱼成活率为100%,显著高于空白对照组和阳性对照组(P<0.05);T3组红鲫鱼的增重率显著高于其他组(P<0.05),体长增长率显著高于空白对照组、阳性对照组和T1组(P<0.05),饲料系数显著低于其他组(P<0.05)。T3组红鲫鱼背部皮肤的红度(a*值)、亮度(L*值)显著高于其他试验组(P<0.05)。T2组和T3组红鲫鱼血清中超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活性显著高于其他组(P<0.05),丙二醛(MDA)含量显著低于其他组(P<0.05)。T3组红鲫鱼血清中过氧化氢酶(CAT)活性显著高于空白对照组、阳性对照组和T1组(P<0.05)。研究表明,饲料中添加破壁红酵母PR61干菌体能够显著提高红鲫鱼的成活率、增重率和抗氧化酶活性,降低饲料系数;破壁红酵母添加量为1.0%时,红鲫鱼的生长指标达最佳水平,鱼体颜色更鲜艳。

The aim of the experiment was to study the amount of oil-producing Rhodotorula strain PR61 as fish feed additive and the effect of wall breaking treatment on feeding effect.A total of 375 red crucian carp seedlings with an average body weight of 4~5 g were randomly divided into five groups with three replicates per group and 25 fish per replicate.Fish in blank control group were fed with 100%basic feed,fish in positive control group were fed with 100%basic feed+0.25%betaine hydrochloride,fish in T1 group were fed with 99.5%basic feed+0.5%unbroken red yeast,fish in T2 group were fed with 99.5%basic feed+0.5%broken red yeast,and fish in T3 group were fed with 99%basic feed+1.0%broken red yeast.The experiment lasted for 28 d.The results showed that the PR61 strain was rich in nutrition,with protein content up to 45.2%,oil content up to 38.93%,the PR61 strain also contained carotenoid,aspartate,serine and totally 17 kinds of amino acids,and the total amino acid was 44.32%.The survival rate of red crucian carp in T2 group and T3 group was 100%,which was significantly higher than that of blank control group and positive control group(P<0.05).The body weight growth rate of red crucian carp in T3 group was significantly higher than that in other groups(P<0.05),the body length growth rate was significantly higher than that in blank control,positive control group and T1 group(P<0.05),and the feed coefficient was significantly lower than that in other groups(P<0.05).The a*value and L*value of the back skin of red crucian carp in T3 group were significantly higher than those in other experimental groups(P<0.05).The activity of SOD and GSH-Px in serum of red crucian carp in T2 group and T3 group were significantly higher than those in other groups(P<0.05),and the content of MDA was significantly lower than that in other groups(P<0.05).The CAT activity of red crucian carp in T3 group was significantly higher than that in blank control,positive control group and T1 group(P<0.05).The study indicates that adding PR61 in feed can significantly improve the survival rate,weight growth rate and antioxidant enzyme activity of fish fry,decrease the feed coefficient.The growth index of the fish fry reaches the best level and the color of fish body is more vivid when the supplemental amount of red yeast is 1.0%.