发酵豆粕替代鱼粉对大黄鱼幼鱼生长性能、体成分、血清生化指标及肝脏组织形态的影响

摘要

A 56 d feeding experiment was conducted to investigate the effects of replacement of fish meal by fermented soybean meal ( FSM) on growth performance, body composition, serum biochemical indices and liver tissue morphology of juvenile large yellow croaker ( Larimichthys crocea ) , and to find the suitable re⁃placement proportion of fish meal by FSM in diets of juvenile large yellow croaker. A 40% fish meal basal diet was formulated using fish meal and wheat gluten meal as main protein sources, and fish oil, soybean oil and soybean lecithin as main lipid sources. Six isonitrogenous ( protein level was 45%) and isolipidic ( lipid level was 10%) experimental diets were formulated by replacing 0 ( R0 group, as control group ) , 15% ( R15 group) , 30% ( R30 group) , 45% ( R45 group) , 60% ( R60 group) and 75% ( R75 group) fish meal with FSM on the basis of the basal diet, respectively. All diets were supplemented with crystalline amino acids such as lysine and methionine except the control group diet. The feeding experiment was carried out in three sea⁃ca⁃ges (1.5 m×1.5 m×2.0 m) of every group and each sea⁃cage had 60 juvenile large yellow croaker with initial body weight of (10.49±0.03) g. The results showed as follows: no significant difference in survival rate (SR) was found among groups (P>0.05), but with the increase of replacement proportion of fish meal by FSM, the SR showed a downward trend. The specific growth rate ( SGR) , weight gain rate ( WGR) and feed conversion ratio ( FCR) in R15, R30 and R45 groups had no significant differences compared with R0 group ( P>0.05); to increase the replacement proportion of fish meal by FSM ( R60 and R75 groups) , the SGR and WGR were significantly decreased ( P<0.05) , and the FCR was significantly increased ( P<0.05) . No signifi⁃cant differences in the contents of crude protein, crude lipid and moisture of whole body were found among groups ( P>0.05) , but whole body ash content has an upward trend with the increase of replacement proportion of fish meal by FSM. Serum biochemical indices in all groups were not significantly different ( P>0.05) , but serum total cholesterol content had a downward trend and serum alanine amino transferase activity had an up⁃ward trend with the increase of replacement proportion of fish meal by FSM. From the liver histological obser⁃vation, replacement proportion of fish meal by FSM more than 30% caused damage to the liver cells, and the replacement proportion was higher, the symptom was more serious. Comprehensive all measured indicators, we suggest that FSM replacement 30% fish meal in the diet containing 40% fish meal of juvenile large yellow croaker is suitable, but high replacement proportions cause the pathological changes of liver tissue and the de⁃crease of growth rate and SR.%本试验旨在研究发酵豆粕替代鱼粉对大黄鱼（ Larimichthys crocea）幼鱼生长性能、体成分、血清生化指标及肝脏组织形态的影响，探索发酵豆粕替代大黄鱼幼鱼饲料中鱼粉的适宜比例。以鱼粉、小麦蛋白粉为主要蛋白质源，鱼油、大豆油和大豆卵磷脂为主要脂肪源，配制含40％鱼粉的基础饲料。以发酵豆粕替代基础饲料中0（ R0组，作为对照组）、15％（ R15组）、30％（ R30组）、45％（ R45组）、60％（ R60组）、75％（ R75组）的鱼粉，并在除对照组饲料外的各饲料中添加适量晶体氨基酸（赖氨酸和蛋氨酸），配制6种等氮（蛋白质水平为45％）等脂（脂肪水平为10％）的试验饲料。养殖试验在海水网箱（1．5 m×1．5 m×2．0 m）中进行，每种试验饲料投喂3个网箱，每个网箱放养60尾初始体重为（10．49±0．03） g大黄鱼幼鱼，养殖时间持续56 d。结果表明：各组大黄鱼幼鱼的存活率无显著差异（ P＞0．05），但随着发酵豆粕替代鱼粉比例的升高有下降趋势；与R0组相比， R15、R30、R45组的特定生长率（ SGR ）、增重率（ WGR ）、饲料系数（FCR）无显著变化（P＞0．05），进一步提高鱼粉替代比例（R60、R75组），SGR、WGR显著降低（P＜0．05），FCR 显著升高（P＜0．05）；各组全鱼粗蛋白质、粗脂肪、水分含量无显著差异（P＞0．05），随着发酵豆粕替代鱼粉比例的升高，全鱼粗灰分含量有上升的趋势；各组血清生化指标没有显著差异（ P＞0．05），但随着发酵豆粕替代鱼粉比例的升高，血清中总胆固醇含量有下降趋势，谷丙转氨酶活力有升高趋势；通过肝脏组织学观察发现，发酵豆粕替代鱼粉比例超过30％后会造成肝脏细胞的损伤，替代比例越高损伤越严重。综合各项测定指标，本研究认为：发酵豆粕替代饲料（含40％鱼粉）中30％的鱼粉较为适宜，过高的替代比例会造成大黄鱼幼鱼肝脏组织病变，导致生长速度、存活率下降。