Histological Changes and Cement Gland Characters of Female Pleopod of Eriocheir sinensis in Different Physiological Stages

The tegument and exoskeleton structure and the cement glands activities of female pleopod in different physiological stages of Eriocheir sinensis were investigated by histological method.The results show that the pleopod tegument consists of epicuticle,exocuticle,endocuticle and epithelial cells.The epithelial cells often connect firmly to cement gland.Cement gland tubules come across the exoskeleton.In different physiological stages (youth,maturation,spawning,and abortion),the pleopods of Taihu spawning crab and Wenzhou local crab have some significant differences,which mainly shows in the ratio and the array of epicuticle,exocuticle,endocuticle and epithelial cells,the amount and the distribution of the setae pockets,the substance in the setae pockets and the cement glands secretion aperture.Also,the cement glands activities and the open gates of the setae pockets are related to the egg attachment.The histological structure of pleopod between Taihu spawning crab and Wenzhou spawning crab is different,which the cement glands and mucus of Taihu spawning crab are much higher than those of Wenzhou spawning crab.The analysis shows that the abortion of Eriocheir sinensis closely relate to the histological structure of pleopod,and the development and activity of cement gland.