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为进一步了解中华绒螯蟹(Eriocheir sinensis)2龄雄体在池塘养殖条件下的生长发育规律,本研究采用养殖实验、活体解剖和显微观察方法,首先研究了池塘养殖过程中二龄雄体的生长、性腺指数(GSI)、肝胰腺指数(HSI)和第二性征(主要包括大螯绒毛长度及其覆盖比例)的变化情况,并探讨了这些指标间的相关性,其次,对成熟雄体的生殖系统外观和组成进行了拍照和描述。结果显示:(1)池塘养殖条件下中华绒螯蟹2龄雄体的体重、甲壳长、甲壳宽和体厚增长主要发生在3~8月,其中4~5月间的增重率和特定增长率最高,9~12月间的体重和形态学参数增长均不显著;肥满度总体上呈先下降后上升的趋势。(2)2龄雄体池塘养殖早期性腺发育较慢,3~5月肉眼很难发现,6月份生精区已经清晰可见,7~11月份性腺指数显著增加,7月份部分个体储精囊中已有精荚,8月份副性腺体积开始迅速增加,整体上,肝胰腺指数(HSI)和性腺指数(GSI)呈显著负相关,而性腺指数(GSI)与生殖蜕壳前的雄体体重及月份均呈显著正相关。(3)2龄雄体的大螯绒毛长度及其内侧绒毛覆盖比例在4~8月呈显著增长趋势,其余月份增加不显著,绒毛长度与覆盖比例、绒毛长度与体重、绒毛覆盖比例与体重、绒毛长度与性腺指数、绒毛覆盖比例与性腺指数都呈显著正相关。(4)2龄成熟雄体的生殖系统由体内和体外两大部分构成,体内部分主要包括精巢、输精管(分为前、中、后三个部分)、副性腺和射精管,输精管后端储存着大量精荚,体外部分主要由阴茎和交接器组成。综上,池塘养殖中华绒螯蟹2龄雄体的生长、性腺发育与其第二性征关系密切,雄体生殖系统组成复杂,今后需要深入研究雄体的性腺发育规律和分期。
In order to understand the law of growth and development of Eriocheir sinensis 2-instar male under pond culture conditions, this study used culture experiment, in vivo dissection and microscopic observation method to study the growth and development of second- GSI, HSI and the second sexual characteristics (mainly including the length and coverage ratio of the chewing fleece), and discussed the correlation between these indexes. Secondly, The male reproductive system appearance and composition were photographed and described. The results showed that: (1) The body weight, length of crustacean shell, width of shell and width of body length of 2nd instar of Chinese mitten crab (Eriocheir sinensis) in pond culture mainly occurred from March to August, among which the weight gain rate and specific The highest growth rate, and no significant increase in body weight and morphological parameters from September to December. The plumpness generally decreased first and then increased. (2) Early male gonadal development of 2-year-old male ponds is relatively slow. From March to May, the naked eye is hard to find. In June, the spermatogenic region has been clearly seen. The gonadal index increased significantly from July to November. In July, There was a fine pod, and the gonadal volume started to increase rapidly in August. On the whole, the HSI and GSI showed a significant negative correlation, while the gonad index (GSI) and reproductive extinct male body weight and month There was a significant positive correlation. (3) The length of the chewing fleece and its inner villi coverage in 2-instar male showed a significant increase from April to August, with no significant increase in other months. The length and coverage of villus, villus length and body weight, villus coverage and body weight , Villus length and gonadal index, villus coverage ratio and gonadal index were positively correlated. (4) The reproductive system of the second-instar mature male consists of two major parts, in vivo and in vitro, including the testes, the vas deferens (divided into three parts before, during and after), the gonadal and ejaculatory ducts, With a large number of fine pods, in vitro part mainly by the penis and the connector. In summary, there is a close relationship between the development of gonadal development and the second sexual characteristics of the male Mongolian crab Eriocheir sinensis in the second instar. The reproductive system of the male reproductive system is complex, so it is necessary to further study the gonadal development and staging of the male in the future.