The efficacy of dietary β-glucan supplementation in golden trevally (Gnathanodon speciosus) was evaluated. The fish were fed five different diets supplemented with 0%, 0.05%, 0.10%, 0.20%, and 0.40% β-glucan for 56 days. After 56 days of culture, survival was the highest when the fish were fed a 0.10% β-glucan diet. Growth rates were higher in fish fed diets supplemented with all β-glucan levels. Lymphocytes increased when the fish were fed a diet supplemented with 0.05% β-glucan, and thrombocytes increased when the fish were fed 0.2% and 0.4% β-glucan-supplemented diets. The total aerobic bacteria count in the gut of golden trevally was higher (p < 0.05) and the total Vibrio counts in the gut of golden trevally were lower (p < 0.05) when the fish were fed any level of β-glucan. Flesh protein content was higher and flesh lipid content was lower when fish were fed β-glucan-supplemented diets at levels greater than 0.1%. When challenged with Streptococcus iniae, fish fed diets containing 0.10% or 0.20% β-glucan exhibited the highest survival rates. The current results suggest that supplementation with 0.05 to 0.2% β-glucan in the diet would be beneficial for the culture of the golden trevally.

中文翻译：

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膳食添加β-葡聚糖对金鲹（Gnathanodon spiosus，鲫科）生长性能、身体成分、肠道微生物和抗病原体能力的影响

评估了在金鲹（ Gnathanodon spiosus ）中添加膳食β-葡聚糖的效果。这些鱼被喂食五种不同的饲料，添加了 0%、0.05%、0.10%、0.20% 和 0.40% β-葡聚糖，为期 56 天。培养56天后，当喂食0.10%β-葡聚糖饲料时，鱼的存活率最高。补充所有β-葡聚糖水平的鱼的生长率更高。当鱼饲喂添加0.05％β-葡聚糖的饲料时，淋巴细胞增加，当鱼饲喂添加0.2％和0.4％β-葡聚糖的饲料时，血小板增加。 饲喂任意水平的β-葡聚糖时，金鲹鱼肠道内需氧菌总数较高（p  <0.05），而弧菌总数较低（p <0.05）。当鱼饲喂β-葡聚糖添加量大于0.1%时，鱼肉蛋白质含量较高，肉脂含量较低。当受到海豚链球菌的攻击时，喂食含有 0.10% 或 0.20% β-葡聚糖的饲料的鱼表现出最高的存活率。目前的结果表明，在日粮中添加0.05%~0.2%的β-葡聚糖有利于金鲹的养殖。