背景:该研究集中在尼罗罗非鱼(Oreochromisniloticus)饮食中补充Ulvafasciata提取物(UFE)对血液和生化标志物的影响,免疫和氧化反应,以及相关基因的表达,对接触嗜水气单胞菌后的病情有特别的兴趣。
方法:在饮食中测试了四种不同水平的UFE:对照组(U0)为0%(0mgkg-1),和递增添加0.05%(50mgkg-1),0.1%(100mgkg-1),和0.15%(150mgkg-1)分别为实验组U50,U100和U150。体重为3.126±0.120g的45条鱼组在90天内饲喂这些饮食。
结果:研究发现,与对照组相比,用UFE治疗的组显示出统计学上的显着增强(p<0.05)。这些改善包括增加红细胞和白细胞计数,更高的血红蛋白浓度,更大的细胞体积,和升高的酶活性-特别是,超氧化物歧化酶,过氧化氢酶,丙氨酸氨基转移酶,和天冬氨酸转氨酶.此外,溶菌酶和吞噬活性明显较高,尤其是U100组暴露后。在接触嗜水气单胞菌之前,所有水平的UFE补充导致TNF-α和COXII基因表达增加,NFκ-B表达降低。挑战之后,UFE摄入导致免疫和抗氧化基因表达水平不同(TNF-α,NFκ-B,SOD,和COXII)在肝脏中,在U50、U100和U150组中观察到最有效的反应。
结论:研究结果强调了膳食UFE作为尼罗罗非鱼的天然抗氧化剂和免疫增强剂的潜力。
BACKGROUND: The study focused on the impact of Ulva fasciata extract (UFE) supplementation in the diets of Nile tilapia (Oreochromis niloticus) on blood and biochemical markers, immune and oxidative responses, and the expression of related genes, with a specific interest in their condition following exposure to Aeromonas hydrophila.
METHODS: Four different levels of UFE were tested in the diets: 0% (0 mg kg- 1) for the control group (U0), and incremental additions of 0.05% (50 mg kg-1), 0.1% (100 mg kg-1), and 0.15% (150 mg kg-1) for the experimental groups U50, U100, and U150 respectively. Groups of 45 fish weighing 3.126 ± 0.120 g were fed these diets over 90 days.
RESULTS: The study found that groups treated with UFE showed statistically significant enhancements (p < 0.05) compared to the control group. These improvements included increased red and white blood cell counts, higher haemoglobin concentrations, greater packed cell volume, and elevated enzyme activities-specifically, superoxide dismutase, catalase, alanine aminotransferase, and aspartate aminotransferase. Additionally, lysozyme and phagocytic activities were notably higher, especially in the U100 group after exposure. Before exposure to Aeromonas hydrophila, all levels of UFE supplementation led to increased expression of TNF-α and COXII genes and decreased NFκ-B expression. After the challenge, UFE intake resulted in varied expression levels of immune and antioxidant genes (TNF-α, NFκ-B, SOD, and COXII) in the liver, with the most effective responses observed in the U50, U100, and U150 groups.
CONCLUSIONS: The findings underscore the potential of dietary UFE as a natural antioxidant and immune booster for Nile tilapia.