文献类型：专著

英文题名：Mechanisms of Feminization and Sex Differentiation in Southern Catfish

作者：Deng S.-P.; Liu Z.-H.; Wang D.-S.

机构：[1]Fisheries College, Guangdong Ocean University, Zhanjiang, China;[2]College of Life Sciences, Chongqing Normal University, Chongqing, China;[3]Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, China

出版社：wiley

出版日期：0

页数：15

纸书定价：0

isbn号：978-111912729-1; 978-111912726-0

语种：英文

外文关键词：Artificial propagation; Feminization; Fertilization biology; Gonadal differentiation; Gynogenesis; Induced sex reversal; Molecular mechanism

外文摘要：The sex ratio of the feral Southern catfish is about 1: 1, while the fish obtained by artificial fertilization are all female. Hence, the possible influence of the microenvironment (pH of the ovarian fluid and concentration of the semen) during artificial insemination and early development (water temperature, water sources and feed) on the sex ratio of the fry was examined. To examine the possibility of the occurrence of gynogenesis during artificial propagation, cytological observations on the insemination processes and the artificial induction of gynogenesis were also performed. However, no male fish were obtained. On the other hand, feeding of Limnodilus spp collected from the wild, and using commercial diets sprayed with EDCs cocktail, resulted in complete feminization of Southern catfish, whereas the control fish displayed approximate 1: 1 sex ratio. Female-to-male sex reversal was achieved by treatment with tamoxifen (an estrogen receptor antagonist) and fadrozole (an aromatase inhibitor). Moreover, several genes involved in sex differentiation, such as cyp19, foxl2 and dmrt1, and three subunits of gonadotropin (gth), gthα, lhβ, and fshβ, were isolated. Their expression patterns were studied under normal gonadal development, feeding of Limnodilus spp and sex reversal conditions. The results showed that dmrt1, foxl2, and cyp19a were closely related to sex differentiation, and the gth subunits were possibly related to ovarian differentiation and oocyte development. Taken together, it suggested that estrogen is highly responsible for the ovarian differentiation and feminization of the catfish fry under artificial propagation, although the mechanism involved remains unclear. ? 2019 John Wiley & Sons Ltd.