Fish meal (FM) usage in aquafeed is fraught with cost and environmental challenges. Alternatives to FM must be readily available and with adequate protein. This 8-weeks study explored the utilization of tuna by-product meal (TBM) without fermentation as a substitute for FM in diet on growth, feed utilization, chemical composition, plasma chemistry, and non-immune responses of olive flounder (Paralichthys olivaceus). Four hundred juveniles (initial weight of 14.7 g) were randomly distributed to 20 tanks (20 fish per tank). The control (Con) diet contained 65% FM without replacement, and in the TBM10, TBM20, TBM30, TBM40, and TBM50 diets, FM was substituted with 10%, 20%, 30%, 40%, and 50% TBM, respectively. Each diet was fed to triplicate groups of fish, but quadruplicate groups for the Con and TBM30 diets. Survival was not different among the experimental diets. Superior weight gain, specific growth rate (SGR), feed efficiency ratio (FER) and protein efficiency ratio were observed in fish fed the TBM40 and TBM50 diets to fish fed all other diets. Condition factor of fish fed the TBM40 and TBM50 diets was higher than that of fish fed the Con diet. Feed consumption, chemical composition, and amino acid profiles of the whole body fish, except for the tryptophan content, viscerosomatic and hepatosomatic indices, plasma biochemical parameters, non-specific immune responses were not affected by the experimental diets. In conclusion, FM up to 50% can be replaced with TBM without impairing growth, feed utilization, nutritional composition, plasma chemistry, and non-specific immune responses of olive flounder when 65% FM was included. The greatest weight gain, SGR, and FER of fish were estimated to be 47.1%, 48.6%, and 46.3% of dietary substitution of FM with TBM, respectively.

水产饲料中鱼粉 (FM) 的使用充满了成本和环境挑战。FM 的替代品必须容易获得并含有足够的蛋白质。这项为期 8 周的研究探讨了使用未经发酵的金枪鱼副产品粉 (TBM) 作为日粮中 FM 的替代品，对橄榄比目鱼 ( Paralichthys olivaceus ) 的生长、饲料利用、化学成分、血浆化学和非免疫反应的影响）。将 400 条幼鱼（初始重量 14.7 克）随机分配到 20 个鱼缸中（每个鱼缸 20 条鱼）。对照 (Con) 日粮含有 65% 的 FM，无需替代，在 TBM10、TBM20、TBM30、TBM40 和 TBM50 日粮中，FM 分别被 10%、20%、30%、40% 和 50% TBM 替代. 将每种饮食喂给一式三份的鱼组，但对 Con 和 TBM30 饮食喂食四组。实验饮食之间的存活率没有差异。在喂食 TBM40 和 TBM50 日粮的鱼中观察到优于喂食所有其他日粮的鱼的体重增加、比生长率 (SGR)、饲料效率比 (FER) 和蛋白质效率比。饲喂 TBM40 和 TBM50 日粮的鱼的条件因子高于饲喂 Con 日粮的鱼。全身鱼的饲料消耗、化学成分和氨基酸谱，除色氨酸含量、内脏和肝体指标、血浆生化参数外，非特异性免疫反应不受实验饮食的影响。总之，当加入 65% 的 FM 时，可以用 TBM 替代高达 50% 的 FM，而不会影响橄榄鲽的生长、饲料利用率、营养成分、血浆化学和非特异性免疫反应。据估计，鱼的最大增重、SGR 和 FER 分别为 FM 与 TBM 饮食替代的 47.1%、48.6% 和 46.3%。包括 65% FM 时橄榄比目鱼的非特异性免疫反应和非特异性免疫反应。据估计，鱼的最大增重、SGR 和 FER 分别为 FM 与 TBM 饮食替代的 47.1%、48.6% 和 46.3%。包括 65% FM 时橄榄比目鱼的非特异性免疫反应和非特异性免疫反应。据估计，鱼的最大增重、SGR 和 FER 分别为 FM 与 TBM 饮食替代的 47.1%、48.6% 和 46.3%。