温度对江黄颡鱼性分化的影响  

Influence of Temperature on Sex Differentiation of Teleost,Pseudobagrus vachelli

作　　者：程晓春[1,2] 林丹军[1,2] 尤永隆[1,2] 

机构地区：[1]福建师范大学生命科学学院 [2]发育与神经生物学高福建省等学校重点实验室,福建福州350007

出　　处：《Zoological Research》2007年第1期73-80,共8页动物学研究（英文）

基　　金：福建省自然科学基金(B0310006);福建省科技厅重点项目(2003No.78)

摘　　要：通过组织学方法观察江黄颡鱼原始生殖细胞(PGCs)迁移、生殖嵴生成和性腺分化,并且探讨在不同温度培育下性腺分化的差异。实验结果显示:1日龄仔鱼PGCs位于鱼体中肠背方的脏壁中胚层中;5日龄时,PGCs迁移到背方的腹膜上皮;8日龄时,生殖嵴形成;14日龄时,原始性腺形成;23日龄时,性腺开始分化。从孵化后的第10天开始,分别用(20±0.5)、(24±1.0自然水温、对照组)、(30±0.5)和(34±0.5)℃4种水温培育仔鱼达25天。实验结束后统计结果显示:对照组和(20±0.5)℃组的雌、雄性比接近1∶1(分别为1∶1.09和1.22∶1);(30±0.5)℃组的为1∶4.89,雄性率达(83.3±0.7)%;(34±0.5)℃组的为2.85∶1,雄性率仅为(26.4±0.4)%。提示(30±0.5)℃可使幼鱼性腺发育趋向雄性,(34±0.5)℃则使幼鱼性腺发育趋向雌性。实验结果表明,江黄颡鱼的性分化是属于温度依赖型性别决定。The migration of the primordial germ cells （PGCs）, formation of the genital ridge, gonad sex differentiation, and their variations under different water temperatures were investigated using histological methods in the teleost, Pseudobagrus vachelli. The results showed that on day 1 the PGCs were at the splanchnic mesoderm above the gut. On day 5, PGCs migrated to the peritoneal epithelium. The genital ridge was formed on day 8 and lacked PGCs. The primordial gonads were formed on day 14. On day 23, the primordial gonads differentiated into ovaries or testes. From day 10 on, the larvae were cultivated in different water temperatures （20 ± 0.5℃, 24 ± 1.0℃ ,30 ± 0.5℃, 34 ± 0.5℃） for 25 days. The control group was cultivated at natural water temperature （24 ± 1.0℃ ）. The sex ratio and percentage of male larvae were calculated after the experiment. At natural water temperature （24 ± 1.0℃） and lower water temperature （20 ± 0.5℃ ）, the sex ratio was approximately 1：1 （1：1.09 and 1.22：1 respectively）. However in the group cultivated at 30 ± 0.5 ℃, the sex ratio was 1：4.89 and the percentage of males was 83.3 ± 0.7%. The sex ratio was 2.85：1 and the per- centage of males was only 26.4± 0.4% in the group cultivated at 34 ± 0.5℃. These results suggest that water at 30 ± 0.5 ℃ influenced the larval gonad towards differentiating into a testis, and water at 34 ± 0.5 ℃ gave the opposite result, i. e. the gonad differentiated into an ovary. This experiment showed that the sex determination of P. vachelli is temperaturedependent sex determination.

关 键 词：江黄颡鱼 性分化 温度 性比 

分 类 号：Q958[生物学—动物学] S917.4[农业科学—水产科学]