This study was conducted to identify the effects of organic acid supplementation on 50 % replacement of fishmeal by soybean meal on the growth performance, hepatic condition and intestinal histology of giant grouper Epinephelus lanceolatus. Giant grouper juveniles were fed three different diets, 50 % fishmeal protein replacement with soybean meal (SBM50), 50 % fishmeal protein replacement with soybean meal added 1% butyric acid supplementation (SBM50 + 1%) and fishmeal diet (FM) as the control. All diets were formulated isoproteic (48 %) and isolipidic (12 %). Experimental fishes were cultured in a recirculating system and fed twice daily until apparent satiation level. Growth performance, hepatic condition and histological changes were observed in the feeding trial. Highest growth was seen in fish fed FM (p < 0.05), followed by SBM50 and SBM50 + 1% showed the lowest growth. Better feed conversion ratio (FCR) and protein efficiency ratio (PER) was also observed in fish fed FM (p < 0.05) followed by fish fed SBM50 and SBM50 + 1%. Meanwhile, hepatic superoxide dismutase activity of fish fed FM was higher, followed by SBM50 + 1% and SBM50 not significant and the thiobarbituric acid reactive substances (TBARS) of fish fed FM was significantly lower (p<0.05) followed by SBM50 + 1% and SBM50. Fish fed FM also showed significantly bigger hepatocytes (p < 0.05) and significantly higher glycogen content (p < 0.05) compared to SBM50 and SBM50 + 1%. On the other hand, inclusion of 1% butyric acid helped in mitigating intestinal inflammation caused by soybean meal although not significant. Findings from this study showed that 1% butyric acid did not help in optimizing high levels of plant based protein for giant grouper juveniles.

本研究旨在确定有机酸补充豆粕替代鱼粉50％对巨石斑鱼石斑鱼的生长性能，肝脏状况和肠道组织学的影响。给巨石斑鱼幼鱼喂食三种不同的日粮，用豆粕替代鱼粉蛋白质含量为50％（SBM50），用豆粕替代鱼粉蛋白质含量为50％，添加了1％的丁酸补充剂（SBM50 + 1％）和鱼粉饮食作为对照。所有饮食均配制成同蛋白（48％）和异脂（12％）。实验鱼在循环系统中进行养殖，每天喂两次，直到出现明显的饱足感。在饲养试验中观察到生长性能，肝状况和组织学变化。在以鱼为食的FM中生长最快（p <0.05），其次是SBM50和SBM50 + 1％显示最低的增长。在饲喂FM的鱼中也观察到更好的饲料转化率（FCR）和蛋白质效率比（PER）（p <0.05），其次是饲喂SBM50和SBM50 + 1％的鱼。同时，饲喂FM的鱼肝超氧化物歧化酶活性较高，其次为SBM50 + 1％和SBM50不显着，饲喂FM的鱼的硫代巴比妥酸反应性物质（TBARS）明显较低（p < 0。05），其次为SBM50 + 1％和SBM50。FM喂养的鱼还显示出明显更大的肝细胞（p <0.05）和显着更高的糖原含量（p <0.05），而SBM50和SBM50 + 1％。另一方面，包含1％的丁酸虽然不明显，但有助于减轻由豆粕引起的肠道炎症。这项研究的结果表明，1％的丁酸无助于优化石斑鱼少年的高含量植物蛋白。