饲料中肉骨粉和豆粕替代鱼粉对虹鳟生长和氮收支的影响

Effects of Meat and Bone Meal and Soybean Meal Substitutes of Fish Meal on Growth Performance and Nitrogen Budget of Rainbow Trout(Oncorhynchus mykiss)

本实验采用混合动植物蛋白(肉骨粉和豆粕1∶1混合)替代鱼粉投喂虹鳟(Oncorhynchus mykiss)幼鱼((46±0.23)g),研究饲料中肉骨粉和豆粕部分替代鱼粉对虹鳟幼鱼生长性能和氮收支的影响。实验设置了4个处理组,依据等氮等脂的原则,用混合蛋白分别替代0、10%、30%和50%的鱼粉,分别为D1、D2、D3和D4,蛋白水平和脂肪水平分别为43.8%和15.1%。将虹鳟幼鱼在16℃的条件下养殖21天,每日饱食投喂一次并且收集残饵粪便。研究表明:用肉骨粉和豆粕部分替代鱼粉不会影响虹鳟幼鱼的终末体重,与全鱼粉组比较,D3组和D4组呈现出较低的生长性能(P<0.05),而10%替代组的摄食率、消化率和特定生长率更高,表现出更好的生长趋势(P<0.05)。氮收支方面,虹鳟幼鱼的氮收支过程中氮排泄是主要损失途径。随着替代水平的上升,氮排泄和损失也呈上升趋势,但是全鱼粉组和10%替代组之间的氮排泄量差异不显著(P>0.05)。实验结果表明,从生长性能和氮收支两方面综合考虑,饲料中用肉骨粉和豆粕替代10%鱼粉投喂虹鳟幼鱼效果更佳;且排泄是虹鳟幼鱼氮收支的主要途径。

In this experiment,the mixed animal and vegetable protein(meat and bone meal and soybean meal concentrate,1∶1 w/w)was used to replace fish meal and feed the rainbow trout juveniles(46±0.23)g in body weight)to study the effects of partial replacement of fish meal by meat and bone meal and soybean meal on the growth performance and the nitrogen budget of the rainbow trout juveniles.Four isonitrogenous and isoenergetic diets with different replacement(0,10%,30% and 50%)of fish meal protein by protein blend were formulated and correspondingly named as D1,D2,D3 and D4.Four experimental diets contained 43.8% of protein and 15.1% of lipid.The rainbow trout juveniles(initial body weight(46±0.23)g were cultured at 16 ℃ and feed once a day with the residual feed and feces collected.The experimental results showed that partial replacement of fishmeal with meat and bone meal and soybean meal did not affect the final body weight of rainbow trout juveniles.Compared with the whole fish meal,D3 and D4 showed lower growth performance(P<0.05).D2 showed higher feeding rate,digestibility and specific growth rate and better growth performance than control(P<0.05).Nitrogen excretion is the main loss in the nitrogen budget of juvenile rainbow trout.With the increase of substitution percentage,nitrogen excretion and loss also showed an upward trend,but there was no significant difference between D1 and D2(P >0.05).Our findings showed that the use of meat and bone meal and soybean meal to replace 10% of fish meal in feed made the rainbow trout to perform better in growth and lower in nitrogen excretion.