贻贝科3种贝类的足结构与足丝分泌能力

为探讨贻贝足的结构与足丝的发生特征,以紫贻贝、条纹隔贻贝和偏顶蛤为实验材料,比较了不同盐度(20,22,24,26,28,30)下3种贻贝足丝分泌速率,详细描述了3种贻贝足组织学结构及足丝分泌过程,探讨了足结构与足丝分泌的关系。结果显示:(1)3种贻贝自足丝剪断2 h后开始分泌新足丝,24 h内3种贻贝的足丝分泌能力存在显著差异,偏顶蛤平均分泌足丝数量为(28.45±6.14)根,紫贻贝和条纹隔贻贝分泌足丝分别为(15.43±2.9)和(6.87±1.67)根;(2)盐度对3种贻贝的足丝分泌有显著影响,偏顶蛤和紫贻贝在盐度20~30下均能分泌足丝,并以盐度22时分泌足丝数量最多,条纹隔贻贝则在盐度高于28时不再分泌足丝;(3)切片显示,贻贝足表面覆有细密的纤毛,腹面有足沟,足沟上有微绒毛;内部由腺体、肌肉和空腔组成,存在黏液腺体、胶原腺体、酚腺体、酶腺体4种不同腺体;3种贻贝足的肌肉组织分布和空腔的大小有所区别,导致足的致密性不同。研究表明,偏顶蛤足丝分泌速率快,分泌足丝数量多,对环境的适应性能力强于紫贻贝和条纹隔贻贝。

Research on the foot structure and byssus formation of three mussels

In order to study the structure of mussels' foot and the characteristics of byssal thread formation (byssus secretion mechanism), the byssal secretion rate of of three mussels (Mytilus edulis, Septifer virgatus and Modiolus modiolus) were compared under different salinity (20, 22, 24, 26, 28 and 30).The histological structure and byssal secretion process of three mussels were discribed. In this study, the relationship between histological structure and byssal thread formation mechanism of three mussels were discussed.The results are as follows.① three mussels began to secrete new byssal thread in 2 h after cutting off the old byssuses, three kinds of mussels showed significant differences in the ability of byssal thread formation within 24 h. The number of byssus was at the average of (28.45±6.14) for M. modiolus, and M. edulis andS. virgatus were (15.43±2.9) and (6.87±1.67), respectively;② salinity caused apparent influences on byssal secretion of three mussels;M. edulis could secrete byssal thread under salinity from 20 to 30 and the byssal number was the highest in 22;S. virgatus stopped secreting byssal thread when salinity is higher than 28;③ The histologic sections presented that there were microvillus covering the mussels foot and groove in the segmental venter which covered with fine cilia; the internal was composed of the glands, muscles and cavities. The glands were mucous glands, collagen glands, phenol glands, enzyme glands. The differences of the muscle distribution and the size of cavity of three mussel foot resulted in the density distinction of foot. Studies suggested that M. modiolus showed stronger ability of environmental adaptation than S. virgatus and M. edulis because of faster secretion of byssuses.