鱼溶浆粉替代鱼粉对草鱼生长及健康的影响

摘要

为了研究饲料中鱼溶浆粉与鱼粉的替代关系,以6%鱼粉为对照( FM组) ,分别以2%( SW2组)、4%( SW4组)、6%( SW6组)的鱼溶浆粉等量替代鱼粉,按照等蛋等能原则配制4种试验饲料,以初始体重为(79.89±0.85) g的草鱼为试验对象,在池塘网箱中进72 d的养殖试验.每组3个网箱,每个网箱放养草鱼20尾. 结果显示:与FM组相比,各替代组草鱼的特定生长率提高了5.77%~12.50%,其中SW2、SW4组与FM组差异显著( P<0.05);各替代组草鱼的饲料系数下降了8.47%~17.51%,SW2、SW4、SW6组与FM组均差异显著( P<0.05). 各替代组草鱼的鱼体粗蛋白质、粗脂肪含量均高于FM组,SW2组蛋白质沉积率显著高于FM组( P<0.05) , SW4、SW6组脂肪沉积率显著高于FM组( P<0.05). 各替代组草鱼的内脏指数与FM组无显著差异( P>0.05) ,SW2组肥满度、肝胰脏指数显著低于FM组( P<0.05). 各替代组草鱼的血清生化指标与FM组均无显著差异( P>0.05). 饲料中总游离氨基酸、组氨酸和腐胺含量与饲料系数和特定生长率的Pearsion相关系数R2 都大于0.8,呈现二次函数关系. 结果表明:本试验条件下,在含6%的鱼粉饲料中以鱼溶浆粉全部替代鱼粉对草鱼的健康无明显不良影响;2%鱼溶浆粉替代等量鱼粉时,草鱼的饲料利用率高,生长速率快,养殖效果优于鱼粉. 饲料中游离氨基酸、生物胺含量在一定范围内对草鱼生长有促进作用,过量则显示副作用;依据本试验结果得到饲料中适宜的腐胺含量为12.5~12.9 mg/kg,总游离氨基酸含量为5 256.7~5 379.5 mg/kg,组氨酸含量为361.1~370.8 mg/kg.%In order to study the substitute relation between stickwater meal and fish meal, a control diet contai-ning 6% fish meal ( FM group) was prepared, three experimental diets were prepared with 2% ( SW2 group) , 4% ( SW4 group) , 6% ( SW6 group) stickwater meal to replace equal amount fish meal, and all the experi-mental diets were isonitrogenous and isoenergetic. The experimental diets were fed to 4 groups of grass carp with the initial body weight of (79.89±0.85) g for 72 days in outdoor farming system. Each group had 3 net cages with 20 fish in each net cage. The results showed as follows:compared with FM group, the specific growth rate in replacement groups were increased by 5.77% to 12.50%, there were significant differences be-tween SW2 or SW4 groups and FM group ( P<0.05); the feed conversion ratio in replacement groups were decreased by 8.47% to 17.51%, there were significant differences between SW2, SW4 or SW6 groups and FM group ( P<0.05) . The crude protein and ether extract contents of whole-body in replacement groups were higher than those in FM group, and the protein retention ratio in SW2 group and the fat retention ratio in SW4 and SW6 group were significantly higher than those in FM group (P<0.05). No significant differences were found in viscerossomatic index between replacement groups and FM group, but the condition factor and hepato-somatic index in SW2 group were significantly lower than those in FM group ( P<0.05) . No significant differ-ences were found in serum biochemical indices among 4 groups ( P>0.05) . Pearsion correlation coefficients R2 of dietary total free amino acid, putrescine and histidine contents with feed conversion ratio and specific growth rate were greater than 0.8, and present a quadratic function relation. The results incate that there are no harmful effects on health of grass carp with stickwater meal to replace all fish meal in the 6% fish meal diet;using 2%stickwater meal to replace equal amount fish meal, grass carp have a higher feed utilization and a faster growth rate, and its effect is better than the fish meal. The contents of dietary free amino acids and biogenic amines in certain extent can improve the growth of grass carp, while overdose may show a side effect. According to the results from this experiment, suitable contents of dietary putrescine, total free amino acid, histidine, lysine, ornithine and taurine are 12.5 to 12.9 mg/kg, 5 256.7 to 5 379.5 mg/kg and 361.1 to 370.8 mg/kg, respec-tively.