大口黑鲈饲料中发酵豆粕营养价值的评定

Evaluation of Nutrient Value of Fermented Soybean Meal in Diet for Largemouth Bass(Micropterus salmoides)

本试验旨在通过养殖试验和消化率试验来评定豆粕和发酵豆粕在大口黑鲈饲料中的营养价值。试验1:选择180条平均体重(4.0±0.1)g的大口黑鲈,随机分为3组,每组3个重复,每个重复20尾鱼。对照组投喂鱼粉含量为35%的基础饲料,试验组(SBM-30和FSBM-30组)分别投喂以豆粕和发酵豆粕替代基础饲料中30%鱼粉的试验饲料。试验期8周。试验2:选择315条平均体重(35.7±1.0)g大口黑鲈,随机分为7组,每组3个重复,每个重复15尾鱼。设计1个鱼粉含量为40%的基础饲料,然后将豆粕和发酵豆粕分别以10%、20%和30%的比例与基础饲料混合,配制成6组试验饲料,分别投喂7组大口黑鲈2周后收集粪便,采用套算法测定不同混合比例下大口黑鲈对豆粕和发酵豆粕中营养物质的表观消化率。结果表明:1)SBM-30组的饲料系数和摄食量显著高于对照组(P<0.05),肝体比显著低于对照组(P<0.05);FSBM-30组的上述指标与对照组没有显著差异(P>0.05)。SBM-30组的干物质、粗蛋白质表观消化率显著低于对照组(P<0.05)。2)30%混合比例下干物质、粗蛋白质、磷和总氨基酸表观消化率显著低于10%混合比例(P<0.05),粗脂肪表观消化率显著高于10%和20%混合比例(P<0.05);30%混合比例下,发酵豆粕的干物质、粗蛋白质、磷和总氨基酸表观消化率显著高于豆粕(P<0.05)。综上所述,豆粕经发酵后,干物质、粗蛋白质、总氨基酸和磷的表观消化率显著提高,在鱼粉含量为35%的饲料中,发酵豆粕可替代30%的鱼粉而不会对大口黑鲈增重和饲料利用产生影响。

A feeding experiment and a digestibility experiment were conducted to evaluate the nutrient value of soybean meal(SBM)and fermented soybean meal(FSBM)in diet for largemouth bass.Experiment 1:a total of 180 largemouth bass with average body weight of(4.0±0.1)g were randomly divided into 3 groups with 3 replicates per group and 20 fish per replicate.Fish in the control group were fed a basal diet which the fish meal content was 35%,and the others in experimental groups(SBM-30 and FSBM-30 groups)were fed the experimental diets which the fish meal in basal diet was replaced by SBM and FSBM at the ratio of 30%.The experiment lasted for 8 weeks.Experiment 2:a total of 315 largemouth bass with average body weight of(35.7±1.0)g were randomly divided into 7 groups with 3 replicates per group and 15 fish per replicate.A basal diet with fish meal content of 40%was prepared,and then SBM and FSBM were mixed with the basal diet at the ratios of 10%,20%and 30%,respectively.Prepared 6 groups of experimental diets,feeding the largemouth bass for 2 weeks,and then the feces were collected for analysis the nutrient apparent digestibilities of SBM and FSBM in different mix ratio for largemouth bass using a substitution method.The results showed as follows:1)the feed conversion ratio and feed intake of SBM-30 group were significantly higher than those of the control group(P<0.05),and the hepatosomatic index was significantly lower than that of the control group(P<0.05);the above indicators of FSBM-30 group had no significant difference with the control group(P>0.05).The apparent digestibilities of dry matter and crude protein of SBM-30 group were significantly lower than those of the control group(P<0.05).2)The apparent digestibilities of dry matter,crude protein,phosphorus and total amino acid in 30%mix ratio were significantly lower than those in 10%mix ratio(P<0.05),and the crude lipid apparent digestibility was significantly higher than that in 10%and 20%mix ratios(P<0.05);in 30%mix ratio,the apparent digestibilities of dry matter,crude protein,phosphorus and total amino acid of FSBM were significantly higher than that of SBM(P<0.05).In conclusion,the apparent digestibilities of dry matter,crude protein,phosphorus and total amino acid of SBM significantly increase after fermentation,and FSBM can replace 30%fish meal in the diet which containing 35%fish meal without negative effects on weight gain and feed utilization of largemouth bass.