【摘要】 将方斑东风螺Babylonia areolata(Link)的早期发育从早期面盘幼体到变态后15d的稚贝分成6个阶段,分别测定各阶段蛋白酶(P)、脂肪酶(L)、淀粉酶(A)和纤维素酶(C)活性。研究结果表明,随着幼体发育的推进,蛋白酶比活力逐渐减小,脂肪酶比活力逐渐增加,淀粉酶和纤维素酶比活力则在变态前逐渐增加,而变态后逐渐减小。比较A/P和(A+C)/(P+L)两种指标指示方斑东风螺幼体发育过程中的食性变化,提出(A+C)/(P+L)用于指示方斑东风螺食性变化更合理、准确。综合比较幼体发育各阶段4种消化酶活性,发现在面盘幼体向稚贝变态期间,幼体消化能力最弱,原因与幼体的变态过程有关。实验结果也验证了贝类具有分泌纤维素酶的能力,该酶在东风螺对纤维素分解中占主导地位。更多还原

【Abstract】 Specific activities of protease(P),lipase(L),amylase(A) and cellulase(C) of Babylonia areolata Link were measured respectively at 6 different stages from early veliger to juvenile 15 days after metamorphosis.The activity of protease was found to decrease gradually over time,while the activity of lipase was detected to increase step by step with larval development.The activities of amylase and cellulase increased slowly within 12 days after hatch,then increased rapidly at competent larva stage and decreased sharply after metamorphosis.A comparison was made between two indexes used as indicators of feeding habit: ratio of amylase activity to protease activity(A/P) and ratio of the sum of amylase and cellulase to the sum of protease and lipase((A+C)/(P+L)).It was concluded that the latter index((A+C)/(P+L)) was more suitable than the former one(A/P) when they were used as indicators of feeding habit.The digestion pattern of Babylonia areolata Link was revealed with the summation of 4 kinds of digestive enzyme activities at the same stage.The digestion of juvenile 3 days after metamorphosis was the weakest among the 6 stages after comparing the summations at different stages.Weak digestion may be one of the most important reasons that influence the survival rate during metamorphosis.The results of specific cellulase activity at the 6 stages indicated that the Gastropoda were able to secrete cellulase themselves.Endogenous cellulase played a vital role for Babylonia areolata to digest cellulose.更多还原