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本试验评价了不同水平的肠膜蛋白替代鱼粉对大鳞副泥鳅(Paramisgurnus dabryanus)幼鱼的生长性能、消化酶活性及抗氧化能力的影响。选用大鳞副泥鳅幼鱼[初始体质量(0.45±0.05)g]1,080尾,随机分成6组,每组3个重复,每个重复60尾鱼。基础饲料(粗蛋白39.64%、粗脂肪6.93%)中鱼粉的添加量为52.8%,试验组采用肠膜蛋白分别替代20%、40%、60%、80%和100%的鱼粉,养殖时间为56d。结果表明:肠膜蛋白替代鱼粉的比例从20%增加到100%,对大鳞副泥鳅幼鱼增重率和特定生长率无显著影响(P>0.05);饲料系数(FCR)则呈先降低后升高的变化趋势,P40组达到最小(1.63),而P80和P100组饲料系数呈明显上升趋势,并显著高于其他试验组(P<0.05)。P80和P100组幼鱼成活率较鱼粉组和低比例替代组显著下降(P<0.05)。肝胰脏及前肠蛋白酶活性均随肠膜蛋白替代水平的增加呈先升高后降低的变化趋势,且均在P60组达到最高,分别为16,185.9μg/(g·min)和4,93.1μg/(g·min)(P<0.05),除与P80组差异不显著外(P>0.05),显著高于其余各试验组(P<0.05)。肠膜蛋白替代水平对泥鳅后肠蛋白酶活性无明显影响(P>0.05);随肠膜蛋白替代水平的升高,肝胰脏、前肠及后肠脂肪酶活性均呈先升高后降低的变化趋势,且均在P60组达到最高(分别为1.35μg/(g·min)、1.66μg/(g·min)和0.44μg/(g·min),肝胰脏和前肠脂肪酶活性除与P80组差异不显著外(P>0.05),显著高于其他试验组(P<0.05);随着肠膜蛋白替代水平的升高,肝胰脏和前肠淀粉酶活性呈先下降后逐渐趋于稳定的趋势,而后肠淀粉酶活性则呈先上升后逐渐趋于稳定的趋势。随着肠膜蛋白替代水平的增加,试验鱼肝胰脏超氧化物歧化酶(SOD)活性呈逐步上升趋势,P80和P100组SOD活性显著高于其余各组(P<0.05);丙二醛(MDA)含量和过氧化氢酶(CAT)的活性各组间无显著差异(P>0.05)。结论 :肠膜蛋白替代对大鳞副泥鳅幼鱼的生长性能没有显著影响,但60%以上的替代水平影响泥鳅幼鱼的饲料效率和成活率。但对肝胰脏和肠道消化酶,及对肝脏抗氧化机能的研究,未发现肠膜蛋白替代与其活性的变化的显著相关性,具体原因需要进一步试验验证。
This experiment evaluated the effects of different levels of intestinal protein alternative fishmeal on growth performance, digestive enzyme activity and antioxidant capacity of juvenile Paramisgurnus dabryanus. Olivefish [initial body mass (0.45 ± 0.05) g] 1,080 were randomly divided into 6 groups with 3 replicates in each group, each with 60 fish. The addition of fishmeal in the basal diet (crude protein 39.64%, crude fat 6.93%) was 52.8%. In the experimental group, the intestinal membrane proteins were used instead of 20%, 40%, 60%, 80% and 100% 56d. The results showed that the proportion of intestinal membrane protein instead of fishmeal increased from 20% to 100%, and had no significant effect on the rate of weight gain and specific growth rate (P> 0.05) (P <0.05). However, the feed conversion coefficient of P80 and P100 was significantly increased, which was significantly higher than that of other experimental groups (P <0.05). The survival rate of juveniles in P80 and P100 group was significantly lower than those in fish meal group and low proportion of replacement group (P <0.05). The activity of hepatopancreas and foregut protease increased first and then decreased with the increase of the intestinal protein replacement level, and reached the peak in the P60 group (16,185.9μg / (g · min) and 4,93.1μg /(g·min)(P<0.05), except for the difference with the P80 group was not significant (P> 0.05), significantly higher than the other test groups (P <0.05). The intestinal protein replacement level had no significant effect on gut rear protease activity (P> 0.05). With the increase of intestinal protein replacement level, the activity of lipase in hepatopancreas, foregut and gut increased first and then decreased (P <0.05), and reached the peak in P60 group (1.35μg / (g · min), 1.66μg / (g · min) and 0.44μg / (g · min) (P <0.05), which was significantly higher than that of P80 group (P <0.05). With the increase of intestinal protein replacement level, the amylase activity of hepatopancreas and foregut decreased first and then gradually Tends to be stable while the amylase activity of the enterocytes tends to first increase and then tends to be stable.The activity of superoxide dismutase (SOD) in the liver and pancreas of the test fish is gradually increased with the increase of the substitution level of the intestinal protein (P <0.05). There was no significant difference in MDA content and catalase (CAT) activity between P80 and P100 groups (P> 0.05) .Conclusion : The intestinal protein replacement has no significant effect on the growth performance of juvenile Paramisgurnus dabryanus, but more than 60% of the substitution level affects feed efficiency and survival rate of juvenile. Hepatopancreas and intestinal digestive enzymes, and the study of the antioxidant of the liver, a significant correlation was found gut membrane protein changes its activity Alternatively, specific reasons require further experimental verification.