湛江沿海西施舌性腺周年变化的组织学观察

Histological Observation on the Annual Changes of Gonad of Coelomactra antiquata in Zhanjiang Coastal Area

[目的]研究湛江沿海已达性成熟年龄的西施舌性腺周年变化。[方法]通过组织学切片和显微观察,对湛江沿海达性成熟年龄的西施舌性腺进行了周年变化研究。[结果]以滤泡的发育程度、生殖细胞发育状态及其在滤泡中数量的多少为标准,对西施舌性腺的组织学观察发现,卵巢及精巢发育过程均可分为增殖期、生长期、成熟期、排放期和休止期5个时期。卵细胞的发生及其发育时期分为卵原细胞期、生长初期、生长中期、生长后期以及成熟期,精子的发生分别经历了精原细胞、初级精母细胞、次级精母细胞、精细胞和精子5个时期。根据肥满度和相对重量的周年变化规律并结合性腺组织切片观察结果,湛江地区的西施舌性腺发育为一年有2~3个排放期。该地区西施舌肥满度和相对总重最低值都出现在12月,为26.79%和25.54%;最高值出现在9月和7月,分别为46.16%和49.42%。[结论]西施舌雌雄性腺发育基本同步,雄性发育略快。

[Objective]In order to study the annual changes of gonad of Coelomactra antiquata in Zhanjiang coastal area.[Method]Through histological serial sections and microscopic observation,the annual changes of gonad of C.antiquata in Zhanjiang coastal area was studied.[Result]According to the histological observation of the gonad of C.antiquata,the development process of ovary and spermary can be divided into five stages:proliferating stage,growing stage,maturing stage,spawning stage,resting stage based on the development degree of follicles,the development state of germ cells and the number of follicular species.According to the occurrence and development of egg cells,it can be divided into oocyte stage,initial phase of growth,metaphase of growth,later phase of growth and mature stage.Sperm generation has gone through five stages:spermatogonia,primary spermatocyte,secondary spermatocyte,spermatid and sperm respectively.By observing the seasonal changes in the rule of fatness,relative weight and the changes in sex gland in histological sections,it was considered that the sex gland development of C.antiquata has two to three in a year in the Zhanjiang area.The lowest values of fatness and relative total weight of C.antiquata in this area appeared in December,which were 26.79% and 25.54% respectively.The highest values were found in September and July,with 46.16% and 49.42% respectively.[Conclusion]The development of male and female gonads is basically synchronous,and the male develops slightly faster.