The aim of this study was to evaluate the effects of dietary supplementation with benzoic organic acid in different concentrations on juvenile Nile tilapia Oreochromis niloticus. Was analyzed the growth performance, hemato-immunological parameters and survival after challenge via gavage with Streptococcus agalactiae. A total of 320 juvenile fish were divided into 16 tanks were divided into four groups according to the concentrations of inclusion of benzoic acid in diets previously formulated to meet the nutritional requirements of the species. Namely control group without inclusion (Control_0%); fish fed diet supplemented with 0.1% benzoic acid (BA_0.1%); fish fed diet supplemented with 0.2% (BA_0.2%) benzoic acid and fish fed diet supplemented with 0.3% (BA_0.3%) benzoic acid for 54 days. Four replicates were included per treatment. The fish fed with BA_0.1% showed better results in weight gain (51.01 ± 3.40), final biomass (1040.88 ± 79.40), specific growth rate (4.18 ± 0.05), food conversion (1.38 ± 0.03), end mean weight (56.96 ± 3.60) and in biomass gain (922.15 ± 58.21) when compared to the control group. The fish fed with BA_0.1% still showed higher percentage of survival (59%) after exposure to the pathogen. Fish fed BA_0.1% presented high haemoglobin values (9.31 ± 1.14), leukocytes (3.45 ± 0.48) and lymphocytes (285.00 ± 40.90) in relation to other treatments, before exposure. Total protein and total immunoglobulin, increased in pre-exposured fish supplemented with 0.1% benzoic acid. These results suggest that the addition of benzoic acid supplemented at 0.1% in the Nile tilapia diet improved the growth performance, hemato-immunological parameters and survival.

本研究的目的是评估日粮中添加不同浓度的苯甲酸有机酸对尼罗罗非鱼Oreochromis niloticus幼鱼的影响。分析了生长性能、血液免疫学参数和通过灌胃无乳链球菌攻击后的存活率。总共320条幼鱼被分成16个鱼缸，根据预先配制的饲料中苯甲酸的含量分为四组，以满足该物种的营养需求。即不包括在内的对照组（Control _0%）；鱼饲料添加了 0.1% 苯甲酸（BA _0.1%）；鱼饲饲料添加 0.2%（BA _0.2%) 苯甲酸和鱼饲料补充 0.3% (BA _0.3% ) 苯甲酸 54 天。每个处理包括四个重复。饲喂_0.1% BA 的鱼在体重增加 (51.01 ± 3.40)、最终生物量 (1040.88 ± 79.40)、特定生长率 (4.18 ± 0.05)、食物转化率 (1.38 ± 0.03)、最终平均体重 (56.96 ± 3.60) 和生物量增益 (922.15 ± 58.21) 与对照组相比。用_0.1% BA 喂养的鱼在暴露于病原体后仍显示出更高的存活率 (59%)。鱼喂 BA _0.1%与其他治疗相比，在暴露前呈现高血红蛋白值 (9.31 ± 1.14)、白细胞 (3.45 ± 0.48) 和淋巴细胞 (285.00 ± 40.90)。总蛋白质和总免疫球蛋白，在添加 0.1% 苯甲酸的预暴露鱼中增加。这些结果表明，在尼罗罗非鱼日粮中添加 0.1% 的苯甲酸可改善生长性能、血液免疫参数和存活率。