The present study evaluated the effects of a commercial soy lecithin‐containing bioemulsifier Lysomax® on growth performance, feed utilization, haematology, immune response and gut histology of adult Nile tilapia (Oreochromis niloticus) fed soybean meal‐based diets, containing plant oil as a lipid source. This emulsifier was incorporated into four isonitrogenous (30% cp), isocaloric (17.5 MJ/kg) test diets, at 0 (control), 0.3, 0.6 and 0.9 g/kg feed. The diets were fed to triplicate groups of adult Nile tilapia, reared in a closed recirculating indoor system, at a daily rate of 3% of fish live weight, twice a day for 60 days. Growth rates, feed utilization efficiency, digestive enzymes activities, blood parameters, liver function enzymes and immunological responses were all boosted (p < .05) with increasing supplemental Lysomax up to 0.3 g/kg diet, followed by a significant retardation (p < .05) at 0.6 and 0.9 levels. Muscle n‐6 and n‐3 polyunsaturated fatty acids (PUFA) and n3/n6 ratio were also increased with increasing Lysomax up to 0.3 level and then levelled off with further increase in dietary Lysomax. The highest length and width of the intestinal microvilli and goblet cell counts were also found in the fish fed on 0.3 g Lysomax/kg diet. However, the quadratic regression analyses of the obtained results indicated that the maximum performance occurred at about 0.45 g/kg of dietary Lysomax. These results suggest that lecithin‐containing bioemulsifier Lysomax® can play a significant role in feed digestion and absorption and improving fish performance and innate immune response. About 0.45 g/kg diet would be sufficient for best performance and health status of farmed Nile tilapia.

中文翻译：

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含卵磷脂的生物乳化剂可提高成年尼罗罗非鱼（Oreochromis niloticus）的生长性能，饲料消化吸收和免疫反应

本研究评估了含有大豆卵磷脂的生物乳化剂Lysomax®对以植物油为原料的以尼罗罗非鱼为食的成年尼罗罗非鱼（Oreochromis niloticus）的生长性能，饲料利用率，血液学，免疫应答和肠道组织学的影响。脂质来源。将该乳化剂以0（对照），0.3、0.6和0.9 g / kg的饲料添加到四种等氮（30％cp），等热量（17.5 MJ / kg）的测试日粮中。将日粮喂给三组成年的尼罗罗非鱼，分成三组，在密闭的循环室内系统中饲养，日剂量为鱼活重的3％，每天两次，共60天。生长速度，饲料利用率，消化酶活性，血液参数，肝功能酶和免疫应答均得到了提高（p<.05），增加Lysomax的补充剂量至0.3 g / kg饮食，随后出现明显的发育迟缓（p<.05）在0.6和0.9的水平上。肌肉n-6和n-3多不饱和脂肪酸（PUFA）和n3 / n6的比例也随着Lysomax的增加而增加至0.3，然后随着饮食中Lysomax的进一步增加而趋于稳定。在以0.3 g Lysomax / kg饲料喂养的鱼中，肠道微绒毛和杯状细胞的最高长度和宽度也被发现。然而，对所得结果的二次回归分析表明，最大性能出现在大约0.45 g / kg的饮食Lysomax中。这些结果表明，含卵磷脂的生物乳化剂Lysomax®可以在饲料的消化吸收，改善鱼的生产性能和先天免疫反应中发挥重要作用。约0.45 g / kg的饮食足以满足养殖尼罗罗非鱼的最佳性能和健康状况。