用木薯粉分别替代基础饲料(面粉含量24%)中0 (对照)、25%、50%、75%、100%的面粉,配制成木薯粉添加量分别为0、6%、12%、18%和24%的5种等氮(含40%粗蛋白质)膨化饲料. 将400尾初重为(50.0±0.5) g的乌鳢随机分为5组,每组4个重复,每个重复20尾. 5组乌鳢随机饲喂1种试验饲料,饲喂60 d后研究木薯粉替代不同比例面粉对乌鳢生长性能、肌肉组成、肝脏健康的影响. 结果表明:随着替代比例的升高,增重率和特定生长率呈逐渐降低的趋势,而饲料系数呈逐渐升高的趋势. 增重率和特定生长率以对照组最高,显著高于75%和100%替代组(P<0.05);而饲料系数则以对照组最低,且显著低于100%替代组(P<0.05). 各组乌鳢的蛋白质效率及肌肉粗蛋白质、粗脂肪和粗灰分含量均没有显著差异( P>0.05). 木薯粉替代不同比例面粉对乌鳢血清总胆固醇和葡萄糖含量没有显著影响( P>0.05) ,但对照组血清甘油三酯含量显著低于其他各组( P<0.05). 各组乌鳢的肝体比随着替代比例的升高呈逐渐增大的趋势,但各组间差异不显著( P>0.05). 与对照组相比,50%和75%替代组肝糖原含量显著升高( P<0.05),但100%替代组肝糖原含量则显著降低(P<0.05). 血清谷草转氨酶活性随着替代比例的升高逐渐升高,且对照组显著低于100%替代组(P>0.05),但血清谷丙转氨酶活性各组间并没有显著差异(P>0.05). 综上所述,木薯粉能够替代饲料中 50%的面粉(木薯粉添加量为12%) ,而不会对乌鳢的生长性能及肝脏健康产生不利影响,但过高的替代比例(≥75%)会影响乌鳢的肝脏健康,进而阻碍鱼体的正常生长.%A 60-day feeding experiment was conducted to evaluate the effects of replacing wheat flour with cas-sava meal on the growth performance, muscle composition and hepatopancreas health of Channa argus. Five isonitrogenous ( contained 40% crude protein) diets were formulated to contain 0, 6%, 12%, 18% and 24%cassava meal repalacing 0 ( control) , 25%, 50%, 75% and 100% wheat flour on the basis of basal diet ( con-tained 24% wheat flour) , respectively. A total of 400 Channa argus with the initial average body weight of (50.0±0.5) g were randomly allocated to 5 groups with 4 replicates per group and 20 fish per replicate, and the fish in the 5 groups were randomly fed one of five diets. The results of showed as follows:the weight gain rate ( WGR) and specific growth rate ( SGR) were showed a descending trend with the replacing ratio increas-ing, while the feed conversion ratio ( FCR) showed a rising tendency. The highest values of WGR and SGR were observed in the control group, and they were significantly higher than those in the 75% and 100% repla-cing groups ( P<0.05); the lowest value of FCR was observed in the control group, and it was significantly lower than that in the 100% replacing groups (P<0.05). No significant differences in protein efficiency ratio ( PER) and the contents of crude protein, crude lipid and ash in muscle were noticed among all groups ( P>0.05). No significant difference in serum total cholesterol (TC) and glucose (Glu) contents were observed a-mong all groups (P<0.05), however, the serum triacylglycerol (TG) content in control group was signifi-cantly lower than that in other groups ( P<0.05) . The hepatosmatic index was gradually increased with the re-placing ratio increasing, but no significant difference was observed among all groups (P>0.05). Compared with the control group, the liver glycogen content in the 50% and 75% replacing groups was significantly in-creased ( P<0.05) , while the that in the 100% replacing group was significantly decreased ( P<0.05) . Serum glutamic-oxalacetic transaminase ( GOT) activity was gradually increaced with the replacing ratio increasing, and it in control group was significantly lower than that in 100% replacing group ( P>0.05) . However, no sig-nificantly difference in serum glutamic-pyruvic transamine ( GPT) activity was noticed among all groups ( P>0.05) . The results show that it is feasible to replace 50% wheat flour with cassava meal ( cassava meal supple-mental level is 12%) in Channa argus diets without negative effects on growth performance and hepatopancreas health. Meanwhile, replacing ratio (≥75%) may lead to a negative effect on hepatopancreas health and stunt the growth of Channa argus.
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