高温和皮质醇对黄颡鱼性别分化的影响  

EFFECTS OF HIGH TEMPERATURE AND CORTISOL ON SEX DIFFERENTIATION OF YELLOW CATFISH(TACHYSURUS FULVIDRACO)

作　　者：齐飘飘 陈敏 于跃 常乐怡 李亚宁 王凌宇[1] 袁勇超[1] 樊启学[1] 沈志刚[1] QI Piao-Piao;CHEN Min;YU Yue;CHANG Le-Yi;LI Ya-Ning;WANG Ling-Yu;YUAN Yong-Chao;FAN Qi-Xue;SHEN Zhi-Gang(Key Laboratory of Freshwater Animal Breeding,Ministry of Agriculture,Engineering Research Center of Green development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt,Ministry of Education,Hubei Provincial Engineering Laboratory for Pond Aquaculture,College of Fisheries,Huazhong Agricultural University,Wuhan 430070,China)

机构地区：[1]华中农业大学水产学院,农业农村部淡水生物繁育重点实验室,教育部长江经济带大宗水生生物产业绿色发展工程研究中心,池塘健康养殖湖北省工程实验室,武汉430070

出　　处：《水生生物学报》2021年第1期106-117,共12页Acta Hydrobiologica Sinica

基　　金：中央高校基本科研业务费专项基金(2662017QD035);湖北省自然科学基金(2018CFB215)资助。

摘　　要：研究以性染色体类型已确定且已有性别特异分子标记的黄颡鱼为研究对象,开展高温与皮质醇诱导黄颡鱼(Tachysurus fulvidraco Richardson)XX个体雄性化组织学进程研究,以期为环境应激诱导鱼类雄性化提供研究基础。通过对每尾鱼采用性别特异性标记鉴定遗传性别(XX或XY)及组织学鉴定生理型性别,仅经过24d的处理(12—35日龄),高温或皮质醇便能诱导XX遗传型个体雄性化。在此过程中,部分XX遗传型个体卵母细胞受到抑制,之后发育成带有卵巢腔的精巢结构。62日龄时,XX伪雄鱼性腺较正常XY雄鱼大,XX伪雄鱼体重与正常XY雄鱼相近,而显著大于未发生性逆转的XX雌鱼。122日龄时,XX伪雄鱼从62日龄带有卵巢腔的精巢结构发育成具有典型的精小叶结构样精巢,且都具有生理性雄鱼特有的生殖突,推测这些雄鱼可能具有与正常雄鱼类似的生殖能力。部分XX个体对高温处理不敏感,没有发生性逆转,温度处理反而加快了卵巢发育的进程,这些个体对高温的耐受性和另外一些发生性逆转的个体对温度的敏感性值得进一步研究。The sex differentiation of fish is extremely susceptible to environmental stresses(such as high temperature,high density,etc.),and generally causes masculinization.In the critical period of sex differentiation,environmental stresses invariably lead to elevated serum cortisol in the process of masculinization.Cortisol treatments caused femaleto-male sex reversal,while antagonist of cortisol synthetase rescued the high temperature-induced masculinization.Estrogen 17β-estradiol(E2)rescued cortisol-and high temperature-induced masculinization.These findings suggest that cortisol is the vital mediator in stress-induced masculinization.Few studies have been explored physiological mechanisms of stress-induced masculinization.The present study investigated the effects of high temperature and cortisol administration on the histological process in the masculinization of XX genotype using yellow catfish Tachysurus fulvidraco with confirmed sex chromosome XX-XY and sex-linked marker as the research object.Combining genotypic sex identification via applying sex-linked markers and phenotypic sex identification through histology,we found that 24 days(12—35 days post-hatching)treatment of high temperature or cortisol induced partial masculinization of XX individuals.During this process,germ cell development of XX gonad was repressed,and therefore it developed into testis-like structure.In addition,we observed seminiferous lobules and typical male genitalia in XX pseudo-male,strongly suggesting that these pseudo-males may have reproductive capacity.We also found that testis size and body weight of XX pseudo-male were significantly higher than those of the XY males and XX females.These results provide important information for understanding the mechanisms of environmental stress factors-induced masculinization.We also found that some XX individuals were not sensitive to high temperature(or cortisol)treatments,and meanwhile,high temperature accelerated ovarian development.The genetic difference between the two different temperat

关 键 词：黄颡鱼 雄性化 性逆转 应激 高温 皮质醇 

分 类 号：S961.6[农业科学—水产养殖]