steroids in natural sex differentiation and sex control of hermaphroditic fish. In ... steroids and their relation to the histology of the natural sex change in sobaity.
Journal of Fish Biology (2001) 58, 305–324 doi:10.1006/jfbi.2000.1450, available online at http://www.idealibrary.com on
REGULAR PAPERS Steroid hormone profiles and correlative gonadal histological changes during natural sex reversal of sobaity kept in tanks and sea-cages K. P. L*, S. A-A A. A-Y Mariculture and Fisheries Department, Kuwait Institute for Scientific Research, P.O. Box 1638, Salmiya, Kuwait 22017 (Received 17 March 2000, Accepted 1 September 2000) The gonadosomatic index of sobaity Sparidentex hasta fits well with the natural spawning season of February–March. At 12 and 24 months all the population matured as males. However, during this time, between April–September intersex gonads were seen. From October of the third year of life, females were seen for the first time. These changes in the histology of the gonads were correlated with the hormonal profile. Testosterone showed no significant correlation with sex but 11-ketotestosterone correlated very well with the mature male gonads and thus can be used for sexing. Oestradiol-17 was higher in sex reversed individuals (females) in the spawning season than in males. The sequence of events in the protandrous sex change of this fish during the first two spawning seasons is male
