Cell Structure and Seasonal Changes of the Androgenic Gland of the Mud Crab Scylla paramamosain (Decapoda: Portunidae)

Hong Liu ； Kwok-Chu Cheung ； Ka-Hou Chu

《Zoological Studies》 47卷6期 (2008/11) Pp. 720-732

並列摘要

In the mud crab, Scylla paramamosain, the androgenic gland (AG) is an elongated structure, situated along the posterior vas deferens. There are 3 types of cells (types Ⅰ, Ⅱ, and Ⅲ) in different seasons and in different parts of the AG of S. paramamosain. They could be easily distinguished based on the cell size, relative proportion of the nucleus in cells, and the abundance of vacuoles. Type I cells are packed together in a high density and have a small cell size, a relatively large nucleus, and a small amount of cytoplasm. These are newly formed gland cells. Type II cells represent the majority of AG cells with the highest activity during the secretory cycle. They have much more cytoplasm with bigger cell sizes than type Ⅰ cells. Type Ⅲ cells are characterized by abundant vacuoles and the disappearance of cell boundaries in some cases, which represent the degeneration stage of the secretory cycle. In different seasons, there are significant differences in terms of gland size, cell boundary, the presence of multinucleated cells, and the occurrence of immature gland cells. The size of the AG increased from January and reached a maximum in the major mating season (July-Sept.). The AG began to degenerate in Oct. In Nov., cell boundaries were difficult to locate. The number of hemocytes greatly increased in Dec., indicating regeneration of the AG. In Mar. to Apr. is a minor mating season, and some spent testes were observed. The AG further developed to the next major mating season. Therefore, the activity of the AG is synchronized with the reproductive cycle.

並列關鍵字

Histology ； Ultrastructure ； Reproduction ； Scylla paramamosain ； Brachyura