摘要
设计了蛋白质含世为45%、35%和25%的三种饵料,以鲜活饵料作对照,研究饵料蛋白质对中华绒螫蟹仔蟹(6±0.5g)消化酶活性的影响。分别于饲养后第10天、20天和40天时取其肝胰腺,测定胰蛋白酶和淀粉酶活性,结果表明:(1)肝胰腺胰蛋白酶活性在投喂鲜活饵料时,整个实验过程中无明显差异(P>0.05);三个实验饵料组蛋白质至第20天时对胰蛋白酶活性才产生显著影响,其中25%蛋白饵料组显著低于其它三个饵料组(P<0.05)。(2)投喂鲜活饵料的仔蟹肝胰腺中淀粉酶比活力在第10d时为49.39 U·mg-1,此后逐渐递减;比较三个蛋白饵料组淀粉酶活性,发现淀粉酶活性自第10天起即受饵料蛋白质的显著影响(P<0.05),至第20天时45%蛋白饵料组比活力为23.85 U·mg-1,较其它两个蛋白饵料组及对照组相比显著降低(P< 0.05),而第40天时对照组和25%蛋白饲料组的淀粉酶比活力显著高于45%和35%二个蛋白饵料组(P< 0.05)。(3)胰蛋白酶mRNA丰度以25%蛋白饵料组为最低,仅0.140,与35%蛋白饵料组较为接近(P> 0.05),而对照饵料组和45%蛋白饵料组的mRNA丰度分别为饲料3组的4.5倍和3.5倍,显著高于25%和35%两个蛋白饵料组(P<0.05)。结果提示仔蟹饵料蛋白质对肝胰腺胰蛋白酶具有显著促进作用,mRNA丰度的变化反映了饵料蛋白质水平导致胰蛋白酶活性的变化是由基?
Three experimental feeds with dietary protein content of 45, 35 and 25% were formulated to rear juvenile Eriocheir sinensis, for 40 days, with initial mean weight of 6 ± 0. 5g, taking live food as control. Juvenile crabs were dissected after feeding 10, 20 and 40 days respectively and hepatopancreas obtained. Then activities of trypsin and amylase in hepatopancreas were measured. The results were as follows: (1) activities of trypsin in hepatopancreas of juvenile crab fed with live food did not show significant difference throughout the trials (P > 0.05). Effects of dietary protein on trypsin activities indicated remarkable difference after feeding 20 days, trypsin activities fed with 25% protein diet was lower than the others ( P < 0.05).(2) the highest value of amylase activities in hepatopancreas of juvenile crabs fed with live food occurred on the 10th day, reaching 49.39, then decreased gradually. Activities of amylase were significantly affected by dietary protein for three diets with different protein levels from the 10th day (P < 0.05). On the 20th day, amylase activity of 45 % protein diet was 23.85, significantly lower than that of the two others ( P < 0.05). And on the 40th day, amylase activity of the control group and 25% protein diet was significantly higher than that of 45% and 35% protein diet (P<0. 05). The experimental results suggested that trypsin in hepatopancreas of juvenile E. sinensis had good adaptation to dietary protein, whereas amylase was inhibited by higher dietary protein level. Higher trypsin activities due to higher dietary protein help to digest more of dietary protein. Trypsin mRNA abundance in hepatopancreas of E. sinensis juveniles fed with live food was the highest of 0.628, and significantly higher than that fed with 35% and 25% protein diets ( P < 0.05), but there was no significant difference between control group and 45% protein diet group. Neither was between 35% and 25% protein diet group. It suggested that molecular regulation of trypsin adaptation to dietary protein levels might attribute to transcription for trypsin.
出处
《水产学报》
CAS
CSCD
北大核心
2005年第2期216-221,共6页
Journal of Fisheries of China
基金
国家自然科学基金项目(30271012
30300265)上海市教育委员会E-研究院建设项目(E03009)
