The dietary cyanocobalamin requirement of fingerling Catla catla (3.2 ± 0.13g; 7.2 ± 0.23 cm) was evaluated by feeding casein–gelatin‐based isonitrogenous (350 g/kg crude protein) and isocaloric (16.72 kJ/g GE) diets. Triplicate groups of fish were fed diets containing different concentrations of cyanocobalamin (0, 0.01, 0.02, 0.04, 0.08, 0.16 and 0.32 mg/kg) to apparent satiation at 07:00, 12:00 and 17:30 hr for 16 weeks. Maximum absolute weight gain (AWG; 28.9 g/fish), specific growth rate (SGR; 2.01%), best feed conversion ratio (FCR; 1.57), protein retention efficiency (PRE; 30.8%) and highest protein gain (PG; 4.8 g/fish) were recorded in fish fed diet containing 0.04 mg cyanocobalamin per kg. Whole body protein and haematological parameters increased significantly (p < .05) as dietary cyanocobalamin levels increased from 0 to 0.04 mg/kg, and thereafter remained unaffected with further inclusion of cyanocobalamin. Antioxidant and immune parameters increased with increasing concentration of dietary cyanocobalamin up to 0.04 mg/kg diet. Liver cyanocobalamin concentrations increased linearly (p < .05) with the incremental levels of dietary cyanocobalamin. Based on broken‐line regression analysis of AWG, PRE, SOD, ALP and TSP activities of fingerling C. catla, the dietary cyanocobalamin requirement ranging between 0.034 and 0.037 mg cyanocobalamin per kg diet is recommended.

中文翻译：

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日粮氰钴胺素对鱼种主要鲤鱼卡特勒（Hamilton）生长性能，非特异性免疫反应，抗氧化能力，血液学参数，身体成分和肝脏中氰钴胺素浓度的影响

用酪蛋白-明胶为基础的异氮（350 g / kg粗蛋白）和等热量（16.72 kJ / g GE）的日粮来评估鱼种Catla catla（3.2±0.13g； 7.2±0.23 cm）的日粮氰钴胺素需求量。一式三份的鱼饲喂含有不同浓度的氰钴胺素（0、0.01、0.02、0.04、0.08、0.16和0.32 mg / kg）的饲料，使其在07：00、12：00和17:30 hr饱食16周。最大绝对增重（AWG; 28.9克/鱼），比生长率（SGR; 2.01％），最佳饲料转化率（FCR; 1.57），蛋白质保留效率（PRE; 30.8％）和最高蛋白质增加（PG; 4.8）在每公斤含0.04毫克氰钴胺素的鱼饲料中记录了每克鱼的摄入量）。全身蛋白质和血液学参数显着增加（p <.05），因为膳食中的氰钴胺素含量从0增至0.04 mg / kg，此后不受进一步加入氰钴胺素的影响。随着饲料中氰钴胺素浓度的增加，抗氧化和免疫参数增加，最高可达0.04 mg / kg。肝脏中氰钴胺素的浓度随 膳食氰钴胺素含量的增加而线性增加（p <.05）。根据鱼种C.AWG的AWG，PRE，SOD，ALP和TSP活性的折线回归分析，建议每公斤日粮中氰钴胺的饮食要求在0.034至0.037 mg氰钴胺之间。