Dos Santos Fabio Aremil Costa, de Sena Souza André, Batista Felipe Soares, Gustavo Soares da Costa Julio, Favero Gisele Cristina, Baldisserotto Bernardo, da Costa Sílvio Teixeira, Vieira Isabela Maraschin, Heinzmann Berta Maria, Bianchini Nadia Helena, Sarmiento Peter Charrie Janampa, Tavares Guilherme Campos, Figueiredo Henrique César Pereira, Luz Ronald Kennedy
Laboratório de Aquacultura, Departamento de Zootecnia de Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Minas Gerais, 31270-901, Brazil.
Laboratório de Aquacultura da Escola de Veterinária da, Universidade Federal de Minas Gerais, Avenida Antônio Carlos, 6627, Belo Horizonte, MG, CEP 30161-970, Brazil.
Vet Res Commun. 2025 Jun 18;49(4):229. doi: 10.1007/s11259-025-10795-9.
This study evaluated the effects of dietary inclusion of the essential oil of Nectandra grandiflora (EONG) on the growth performance, blood biochemistry, intestinal histomorphometry, and Streptococcus agalactiae infection resistance of juvenile Oreochromis niloticus. This is the first study to report the use of EONG as a feed additive for this species in a recirculating aquaculture system. A total of 224 juveniles were distributed in a completely randomized design and fed diets containing 0.0 (control), 0.5, 0.75, and 1.5 mL EONG kg feed⁻ for 30 days. Final weight (p < 0.05) and daily weight gain (p < 0.05) were highest at 0.829 and 0.933 mL EONG kg⁻, respectively. Daily feed intake (p < 0.05) and feed conversion ratio (p < 0.05) were lowest at 0.875 and 0.926 mL EONG kg⁻, respectively. After 30 days, survival for 0.75 mL EONG kg feed⁻ was significantly higher (p < 0.05) than that for the control. Plasma glucose levels decreased (p 0.05) with 1.5 mL EONG kg feed⁻. Triglycerides, cholesterol, and total protein were lower (p 0.05) in all EONG-supplemented groups. Central hepatic vein area (p < 0.05) and intestinal villus width (p < 0.05) were greater at 1.5 mL EONG kg feed⁻. Only dietary supplementation with 0.75 mL EONG kg feed⁻ was able to significantly reduce mortality caused by S. agalactiae, demonstrating its increased protective efficacy. Additionally, post-challenge bacterial recovery was lower for 0.5 and 0.75 mL EONG kg feed⁻. Supplementation with 0.75 mL EONG kg feed⁻ was the most effective dose as it resulted in improved growth, survival, and protection against S. agalactiae.
本研究评估了在尼罗罗非鱼幼鱼日粮中添加大花莲叶楠精油（EONG）对其生长性能、血液生化指标、肠道组织形态计量学以及抗无乳链球菌感染能力的影响。这是首次报道在循环水养殖系统中使用EONG作为该物种饲料添加剂的研究。总共224尾幼鱼采用完全随机设计，投喂含0.0（对照）、0.5、0.75和1.5 mL EONG kg⁻饲料的日粮，持续30天。最终体重（p < 0.05）和日增重（p < 0.05）分别在EONG添加量为0.829和0.933 mL kg⁻时最高。日采食量（p < 0.05）和饲料转化率（p < 0.05）分别在EONG添加量为0.875和0.926 mL kg⁻时最低。30天后，EONG添加量为0.75 mL kg⁻组的存活率显著高于对照组（p < 0.05）。饲料中添加1.5 mL EONG kg⁻时，血浆葡萄糖水平降低（p 0.05）。所有添加EONG的组中甘油三酯、胆固醇和总蛋白含量均较低（p 0.05）。饲料中添加1.5 mL EONG kg⁻时，肝中央静脉面积（p < 0.05）和肠绒毛宽度（p < 0.05）更大。只有日粮中添加0.75 mL EONG kg⁻能够显著降低无乳链球菌引起的死亡率，表明其保护效果增强。此外，攻毒后0.5和0.75 mL EONG kg⁻组的细菌回收率较低。添加0.75 mL EONG kg⁻是最有效的剂量，因为它能改善生长、提高存活率并增强对无乳链球菌的抵抗力。
