Souza ElizÂngela M DE, Souza Renilde C DE, Melo JosÉ F B, Costa Mateus M DA, Souza Seldon A DE, Souza Anderson M DE, Copatti Carlos E
Programa de Pós-Graduação em Zootecnia, Universidade Federal da Bahia, Salvador, BA, Brazil.
Universidade Federal do Vale do São Francisco, Petrolina, PE, Brazil.
An Acad Bras Cienc. 2020;92 Suppl 1:e20190140. doi: 10.1590/0001-3765202020190140. Epub 2020 Jul 3.
The objective of the present study was to evaluate growth, biochemical, hematological and intestinal enzymes responses and survival of Nile tilapia juveniles fed a diet containing the essential oil of lemongrass Cymbopogum flexuosus (EOCF) and infected by Aeromonas hydrophila. Five diets were evaluated (in quadruplicate) with increasing levels of EOCF (0.0 - control; 0.25; 0.50; 1.0 and 2.0 mL kg diet-1). On day 45, eight fish per treatment were sampled and blood, liver and intestine samples were taken. Others eight fish per treatment were infected with A. hydrophila followed by a 15-day period of observation. Citral is the main constituent of EOCF. The inclusion of 2.0 mL EOCF kg diet-1 increased specific growth rate and survival after A. hydrophila infection and decreased feed conversion ratio of Nile tilapia. In general, higher concentrations of EOCF in the diet reduced plasma glucose and triglycerides levels, and increased plasma amino acids, alanine aminotransferase (ALT) and hepatic ALT levels, hematological parameters, and the activity of intestinal enzymes. It was concluded that the inclusion of 2.0 mL EOCF kg diet-1 improved growth performance, biochemical and physiological responses and decreased mortality of Nile tilapia after A. hydrophila infection.
本研究的目的是评估饲喂含有柠檬草（Cymbopogum flexuosus）精油（EOCF）日粮并感染嗜水气单胞菌的尼罗罗非鱼幼鱼的生长、生化、血液学和肠道酶反应以及存活率。评估了五种日粮（每组四份重复），其中EOCF水平逐渐增加（0.0 - 对照；0.25；0.50；1.0和2.0 mL kg日粮-1）。在第45天，对每个处理的八条鱼进行采样，并采集血液、肝脏和肠道样本。每个处理的另外八条鱼感染嗜水气单胞菌，随后进行15天的观察期。柠檬醛是EOCF的主要成分。日粮中添加2.0 mL EOCF kg日粮-1可提高尼罗罗非鱼在感染嗜水气单胞菌后的特定生长率和存活率，并降低饲料转化率。一般来说，日粮中较高浓度的EOCF可降低血浆葡萄糖和甘油三酯水平，并提高血浆氨基酸、丙氨酸转氨酶（ALT）和肝脏ALT水平、血液学参数以及肠道酶活性。得出的结论是，日粮中添加2.0 mL EOCF kg日粮-1可改善尼罗罗非鱼在感染嗜水气单胞菌后的生长性能、生化和生理反应，并降低死亡率。
