Xiamen Key Laboratory for Feed Quality Testing and Safety Evaluation, Fisheries College, Jimei University, Xiamen, 361021, China.
The Key Laboratory of Mariculture (Education Ministry of China), Ocean University of China, Qingdao, 266003, China.
Fish Shellfish Immunol. 2019 Jan;84:987-997. doi: 10.1016/j.fsi.2018.11.009. Epub 2018 Nov 4.
This study examined the effects of replacing fish meal (FM) with three different types of soybean meal (SM) including untreated SM, Bacillus pumillus SE5 (BP) fermented SM (BPFSM) and Pseudozyma aphidis ZR1 (PA) fermented SM (PAFSM) in diets for Japanese seabass (Lateolabrax japonicus). A basal diet was formulated using FM (FM diet), and six other diets were produced by substituting 40 or 80% of FM with SM, BPFSM or PAFSM (SM40, SM80, BPFSM40, BPFSM80, PAFSM40 and PAFSM80 diets). Each diet was fed to triplicate groups of fish (7.14 ± 0.05 g) twice daily for eight weeks. Replacing 40% of FM with SM sources did not significantly influence growth (P > 0.05), while increasing the substitution level to 80% led to reduced growth rates (P < 0.05). The groups received SM80 and PAFSM80 diets showed significantly higher feed conversion ratio and lower protein digestibility than FM group. Furthermore, notably lower dry matter digestibility was detected in SM80 group. Remarkably lower serum total antioxidant capacity was found in the SM80 group, and catalase activity did not significantly differ between FM and BPFSM40 groups. Serum malondialdehyde concentration was enhanced by increasing FM replacement level and the highest value was observed in the SM80 fed fish. FM and PAFSM40 groups showed significantly higher lysozyme activity than the SM80 group. Fish fed the BPFSM40 diet exhibited the highest complement C3 activity and the lowest value was observed in the SM80 group. Expression of lysozyme gene in spleen was down-regulated in the SM80 group, and no significant difference in expression of C3 gene was found among FM, BPFSM40 and PAFSM40 groups. Digestive enzymes activity and gut morphology were significantly influenced by FM replacement. Expression of HSP70 and pro-inflammatory genes including TNF-α and IL-1β were up-regulated by FM replacement and relatively lower expression levels were found by using fermented SM. An opposite trend was observed for the anti-inflammatory TGF-β gene expression. Serum d-lactate concentration was significantly increased by replacing 80% of FM with any of the SM sources. These findings indicated that using fermented SM, particularly BPFSM, beneficially influences feed utilization, antioxidant capacity, innate immunity and gut health in juvenile Japanese seabass.
本研究探讨了用三种不同类型的豆粕（未处理豆粕、枯草芽孢杆菌 SE5（BP）发酵豆粕（BPFSM）和假丝酵母 ZR1（PA）发酵豆粕（PAFSM）替代鱼粉（FM）对日本鲈鱼（Lateolabrax japonicus）饲料的影响。基础饲料使用 FM（FM 饲料）配制，然后用 SM、BPFSM 或 PAFSM 替代 40%或 80%的 FM，分别制备六种其他饲料（SM40、SM80、BPFSM40、BPFSM80、PAFSM40 和 PAFSM80 饲料）。每种饲料以 7.14±0.05g 的体重给三重复组的鱼（每组 7.14±0.05g）每日投喂两次，共八周。用 SM 替代 40%的 FM 对生长没有显著影响（P>0.05），但替代水平增加到 80%会导致生长速度降低（P<0.05）。SM80 和 PAFSM80 组的饲料转化率和蛋白质消化率显著高于 FM 组。此外，SM80 组的干物质消化率明显较低。SM80 组的血清总抗氧化能力显著降低，而 FM 和 BPFSM40 组的过氧化氢酶活性没有显著差异。随着 FM 替代水平的增加，血清丙二醛浓度升高，SM80 组最高。FM 和 PAFSM40 组的溶菌酶活性显著高于 SM80 组。BPFSM40 组的补体 C3 活性最高，SM80 组最低。脾脏中溶菌酶基因的表达在 SM80 组下调，而 FM、BPFSM40 和 PAFSM40 组之间 C3 基因的表达没有显著差异。替代 FM 会显著影响消化酶活性和肠道形态。替代 FM 会诱导 HSP70 和促炎基因（TNF-α 和 IL-1β）表达上调，而用发酵 SM 替代时表达水平较低。抗炎 TGF-β 基因的表达则呈现相反的趋势。用 SM 替代 80%的 FM 会显著增加血清 d-乳酸浓度。这些发现表明，用发酵 SM（特别是 BPFSM）替代 FM 会有益地影响幼日本鲈鱼的饲料利用、抗氧化能力、先天免疫和肠道健康。
