Globally, with the expansion of aquaculture, the demand for functional feeds is continuously increasing, and effort is in progress to improve the efficiency of the feed additives. Herein, nano-scale chitosan (CNP) with an average size < 35 nm was prepared by using an ionotropic gelation method, and a completely randomized feeding experiment in three replicates under mimic aquaculture conditions was conducted to evaluate its efficiency as feed additive with respect to micro-scale chitosan (CH). Three 35% protein experimental diets, C-0 without supplement while C-1 and C-2 supplemented with CH and CNPs, respectively, at the same inclusion level, i.e., 5 g kg⁻¹ diet was prepared and fed to the respective groups of silver carp Hypophthalmichthys molitrix . The experiment was continued for successive 60 days. The results indicated most significant ( P  < 0.05) effect of CNPs on the growth performance parameters (% weight gain, specific growth rate, and average daily weight gain), feed conversion ratio, non-specific immunity (WBCs count, lysozyme activity, immunoglobulin levels, phagocytic and respiratory burst activities), and resistance against Staphylococcus aureus infection. However, CH-supplementation did not show any profound effects on the growth rate ( P  < 0.05) with decreased plasma cholesterol level ( P  > 0.001). Our results indicate the improved efficiency of CNPs and recommend it as a feed additive to enhance fish productivity and fish immune response towards the invading pathogens.

中文翻译：

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日粮微米级和纳米级壳聚糖对silver鱼对 苯二甲鱼 对 金黄色葡萄球菌 感染的生长性能，非特异性免疫和抗性的比较作用

在全球范围内，随着水产养殖业的发展，对功能性饲料的需求不断增长，并且正在努力提高饲料添加剂的效率。本文中，通过离子化凝胶法制备了平均粒径小于35 nm的纳米级壳聚糖（CNP），并在模拟水产养殖条件下进行了三个重复的完全随机喂养实验，以评估其作为饲料添加剂的效率。微型壳聚糖（CH）。三种35％蛋白质实验饮食，C-0不添加，而C-1和C-2分别以相同的包含水平添加CH和CNP，即准备5 g kg ^-1饮食，并分别喂养鲤 Hy眼 鱼 。实验连续进行了60天。结果表明 ，CNP对生长性能参数（增重％，比生长速率和日均增重），饲料转化率，非特异性免疫力（白细胞计数，溶菌酶活性，免疫球蛋白）的影响最为显着（ P <0.05）水平，吞噬和呼吸爆发活性）以及对 金黄色葡萄球菌 感染的抵抗力 。然而，CH-补充没有显示出对生长速率的任何有深刻的影响（ P  与血浆胆固醇降低水平（<0.05） P  > 0.001）。我们的结果表明，CNP的效率有所提高，建议将其作为饲料添加剂来提高鱼类生产力和鱼类对入侵病原体的免疫反应。