饲料脂肪水平对大规格额尔齐斯河银鲫生长性能、饲料利用、体成分及血清生化指标的影响

Effects of Dietary Lipid Level on Growth Performance,Feed Utilization,Body Composition and Serum Biochemical Indices of Large Size Gibel Carp(Carassius auratus gibelio Block)from Irtysh River

本试验旨在研究饲料脂肪水平对大规格额尔齐斯河银鲫(Carassius auratus gibelio Block)生长性能、饲料利用、形体指标、体成分及血清生化指标的影响,以期确定大规格额尔齐斯河银鲫饲料中脂肪的适宜水平。试验配制脂肪水平分别为3.88%、6.52%、8.87%、11.25%和13.52%的5种实用饲料,在21~23℃水温下投喂初始体质量为(52.78±0.10)g的大规格额尔齐斯河银鲫8周。结果显示:饲料脂肪水平对试验鱼的末体质量,全鱼粗蛋白质和粗灰分含量,肌肉水分、粗蛋白质和粗灰分含量,血清谷丙转氨酶、谷草转氨酶活性以及总蛋白、白蛋白、球蛋白含量均无显著影响(P>0.05)。随着饲料脂肪水平的升高,试验鱼的增重率、特定生长率和饲料效率先升高后降低,均在饲料脂肪水平为8.87%时达到最高值;全鱼和肌肉水分含量逐渐下降,而全鱼和肌肉粗脂肪含量逐渐上升;血清甘油三酯、高密度脂蛋白、低密度脂蛋白含量先逐渐增加,在饲料脂肪水平达到8.87%后保持相对稳定。摄食脂肪水平为3.88%饲料的试验鱼血清总胆固醇含量显著低于摄食其他饲料的试验鱼(P<0.05)。以特定生长率和饲料效率为评价指标,分别进行折线和二次回归分析,得出大规格额尔齐斯河银鲫饲料中脂肪的适宜水平为8.51%~10.45%。

This experiment was conducted to investigate the effects of dietary lipid level on growth perform⁃ance,feed utilization,morphological indicators,body composition and serum biochemical indices of large size gibel carp(Carassius auratus gibelio Block)from Irtysh river,and to determine the dietary optimal lipid level.Five practical diets were prepared with lipid levels at 3.88%,6.52%,8.87%,11.25%and 13.52%,respec⁃tively,to feed large size gibel carp from Irtysh river[initial body weight was(52.78±0.10)g]for 8 weeks at 21 to 23℃water temperature.The results showed that,dietary lipid level had no significant influences on the final body weight,the contents of crude protein and ash of whole body,the contents of moisture,crude protein and ash of muscle,the activities of alanine aminotransferase and aspartate aminotransferase and the contents of total protein,albumin and globulin in serum(P>0.05).With the increase of dietary lipid level,the weight gain rate,specific growth rate and feed efficiency were firstly increased and then decreased,and all of them reached the highest values when dietary lipid level was 8.87%;the moisture content of whole body and muscle gradually decreased,and the ether extract content of whole body and muscle gradually increased;the contents of triglyceride,high⁃density lipoprotein and low⁃density lipoprotein in serum gradually increased at first and then remained relatively stable when dietary lipid level reached 8.87%.The serum total cholesterol content of fish fed diet with 3.8%lipid level was significantly lower than that of fish fed other diets(P<0.05).With the specific growth rate and feed efficiency as evaluation indices,through broken line analysis and quadratic regres⁃sion analysis,respectively,the dietary optimal lipid levels of large size gibel carp from Irtysh river are 8.51%to 10.45%.