An 8-week feeding trial was conducted to evaluate the potential of fish meal replacement with corn gluten meal (CGM) in diets for golden pompano (Trachinotus ovatus). A 2×3 layout was used. A basal diet (C) was formulated to contain 250 g/kg fish meal. In the test diets, 20, 40 and 60% of the fish meal in the basal diet was respectively replaced by either CGM (R) or γ-ray irradiated CGM (IR). The six test diets were abbreviated as R20, R40, R60, IR20, IR40 and IR60 (CGM was used as a fish meal substitute in diets R20, R40 and R60, and γ-ray irradiated CGM was used as a fish meal substitute in diets IR20, IR40 and IR60). All the diets were formulated at equal protein and lipid levels. Initial body weight of fish was (31.9±0.2) g. The results showed that weight gain, feed intake, feed conversion ratio (FCR), nitrogen retention efficiency (NRE), phosphorus retention efficiency (PRE) and body content of phosphorus were significantly affected by fish meal replacement level, while body phosphorus content was affected by the type of CGM used. Feed intake and weight gain decreased with increasing fish meal replacement level, regardless of CGM or γ-ray irradiated CGM as a fish meal substitute. At the same fish meal replacement level, no significant differences were found in the feed intake, weight gain, FCR, NRE, PRE, condition factor, hepatosomatic index and body composition (moisture, crude protein, crude lipid and ash) between fish fed the diets with fish meal replaced by CGM and γ-ray irradiated CGM. No significant differences were found in feed intake, weight gain, FCR and NRE between fish fed diets C and R20, suggesting that dietary fish meal level for T. ovatus can be reduced to 200 g/kg when CGM was used as a fish meal substitute. This study reveals that γ-ray irradiation could not improve CGM as a fish meal substitute in T. ovatus diet.%通过8周饲养实验检验了γ-射线辐照处理对利用玉米蛋白粉替代卵形鲳鲹饲料中鱼粉的影响.采用2×3实验设计.对照饲料(C)中鱼粉含量为250 g/kg.用玉米蛋白粉或γ-射线辐照玉米蛋白粉分别替代饲料C中鱼粉的20%、40%或60%,配成6种等氮等脂饲料(R20、R40和R60:以玉米蛋白粉为鱼粉替代物;IR20、IR40和IR60:以γ-射线辐照玉米蛋白粉为鱼粉替代物).实验鱼初始体质量为(31.9±0.2)g.结果显示,饲料鱼粉替代水平显著影响鱼体增重(WG)、摄食率(FI)、饲料系数(FCR)、氮储积效率(NRE)、磷储积效率(PRE)和鱼体磷含量,而γ-射线辐照处理显著影响鱼体的磷含量.无论以何种玉米蛋白粉作为鱼粉替代物,FI和WG均随饲料鱼粉替代水平增加而下降.在相同替代水平下,使用玉米蛋白粉或γ-射线辐照玉米蛋白粉作鱼粉替代物对FI、WG、FCR、NRE、PRE和鱼体组成(水分、粗蛋白、粗脂肪和灰分)无显著不同的影响.摄食饲料R20的鱼FI、WG、FCR和NRE与摄食饲料C的鱼相比无显著性差异,表明通过添加玉米蛋白粉可将卵形鲳鲹饲料中鱼粉含量降低至200 g/kg.研究表明,通过γ-射线辐照处理不能提高玉米蛋白粉替代饲料鱼粉的水平.
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