Ruenkoed Supranee, Nontasan Supap, Phudkliang Janjira, Phudinsai Piyachat, Pongtanalert Piyapong, Panprommin Dutrudi, Mongkolwit Keatipong, Wangkahart Eakapol
Research Institute, Pucheng Chia Tai Biochemistry Co., Ltd., Pucheng, Fujian, 353400, China.
Laboratory of Fish Immunology and Nutrigenomics, Applied Animal and Aquatic Sciences Research Unit, Division of Fisheries, Faculty of Technology, Mahasarakham University, Khamriang Sub-district, Kantarawichai, Maha Sarakham, 44150, Thailand; Faculty of Tourism and Hotel Management, Mahasarakham University, Talad Sub-district, Muang, Maha Sarakham, 44000, Thailand.
Fish Shellfish Immunol. 2023 Oct;141:109056. doi: 10.1016/j.fsi.2023.109056. Epub 2023 Sep 9.
Dietary GABA plays an important role in a variety of physiological functions in animals, but this has been rarely reported in fish. This study investigated the effects of dietary supplementation with GABA on growth, serum antioxidant indicators, digestive enzyme activities, intestinal morphology, and the gene expression of Nile tilapia. Diets containing three different GABA concentrations, 0 (control), 200 mg/kg (GABA200), and 500 mg/kg (GABA500), were fed to Nile tilapia (6.97 ± 0.34 g) for 56 days. The present study found that increasing dietary GABA content could increase the fish growth performance including final body weight, weight gain, specific growth rate, average daily gain, protein efficiency ratio, and feed efficiency compared to the control diet. Interestingly, the feed conversion ratio was improved by dietary GABA supplementation. The antioxidant enzyme activities against ammonia stress of fish fed the GABA diets were significantly higher than the corresponding control group throughout the 96-h ammonia exposure. Moreover, significant increases in digestive enzyme activities including protease, amylase and lipase were found in fish fed the GABA diets. Intestinal morphology analysis revealed increased heights and widths of intestinal villi as well as thickness of the intestinal muscularis in fish fed the GABA diets compared to the control diet. The supplementation of diets with GABA significantly increased the expression level of immune- and growth-related genes. The above results indicate that dietary GABA can modulate the growth, improve their immune response and antioxidant status, gut health and morphology and gene expression of Nile tilapia. Therefore, GABA is a promising feed additive for Nile tilapia aquaculture.
日粮中的γ-氨基丁酸（GABA）在动物的多种生理功能中发挥着重要作用，但在鱼类中的相关报道较少。本研究探讨了日粮中添加GABA对尼罗罗非鱼生长、血清抗氧化指标、消化酶活性、肠道形态以及基因表达的影响。将含有三种不同GABA浓度（0（对照）、200mg/kg（GABA200）和500mg/kg（GABA500））的日粮投喂给尼罗罗非鱼（6.97±0.34g），持续56天。本研究发现，与对照日粮相比，增加日粮中GABA含量可提高鱼类生长性能，包括终末体重、增重、特定生长率、平均日增重、蛋白质效率比和饲料效率。有趣的是，日粮添加GABA可改善饲料转化率。在整个96小时的氨暴露过程中，投喂GABA日粮的鱼类对抗氨应激的抗氧化酶活性显著高于相应对照组。此外，在投喂GABA日粮的鱼类中发现消化酶活性（包括蛋白酶、淀粉酶和脂肪酶）显著增加。肠道形态分析显示，与对照日粮相比，投喂GABA日粮的鱼类肠绒毛高度和宽度以及肠肌层厚度均增加。日粮添加GABA显著提高了免疫和生长相关基因的表达水平。上述结果表明，日粮GABA可调节尼罗罗非鱼的生长，改善其免疫反应、抗氧化状态、肠道健康和形态以及基因表达。因此，GABA是尼罗罗非鱼养殖中一种有前景的饲料添加剂。
