Regulation of sexual succession in the protogynous black sea bass, Centropristis striatus (osteichthyes: Serranidae)

Sex-change and gonadal steroids in sequentially-hermaphroditic teleost fish

“…Most studies of sex-change in fishes have utilized blood-steroid correlates of various gonadal stages in fish experiencing natural sexual transition (Cochran and Grier, 1991;Guiguen et al, 1993;Johnson and Thomas, 1995;Johnson et al, 1998;Lone et al, 2001). However, this method of investigation generates only snapshots of a continuous process and thus makes assumptions about the continuity of changes that may occur.…”

“…The result is a manifestation of elevated E 2 levels, the abrogation of 11KT synthesis, and a subsequent proliferation and degeneration of ovarian and testicular tissue (respectively) (Reinboth et al, 1986;Kime et al, 1991;Godwin and Thomas, 1993;Guiguen et al, 1993;Condeca and Canario, 1995;Guiguen et al, 1995;Chang and Lin, 1998;Lee et al, 2000). Correspondingly, protogynous transition generally involves reciprocal changes to the activities of the same enzymes and their respective steroidal products (Nakamura et al, 1989;Cardwell and Liley, 1991;Cochran and Grier, 1991;Johnson and Thomas, 1995;Bhandari et al, 2003). In at least some species, however, it appears that a change in the activity (i.e.…”

“…For example, the steroidal regulation of sex-change induced by the release of suppressive dominance (Godwin and Thomas, 1993) may be qualitatively and quantitatively different to that in fish where sex-change is induced by other (unknown?) factors (Yeung and Chan, 1987a, b;Cochran and Grier, 1991;Lone et al, 2001). Interestingly, testicular incubates from gonochoristic fighting fish (Betta splendens) utilized two different pathways to synthesize androgens (Leitz and Reinboth, 1987).…”

Steroid hormone profiles and correlative gonadal histological changes during natural sex reversal of sobaity kept in tanks and sea‐cages

“…In T. duperrey, plasma T did not change in males, intersexes or females (Nakamura et al, 1989). Similarly, in two other protogynous species, Monopterous albus (Zuiew) and Centropristes striatus (L.), T levels could not be correlated with the process of sex change (Chan & Yeung, 1989;Cochran & Grier, 1991). However, plasma T levels increased during the change of sex from female to male in the protognyous grouper, Epinephelus microdon (Bleeker) and decreased when the change was reversed (Debas et al, 1990).…”

“…Some sex-changing fishes display the normal teleost pattern of steroid levels, with higher levels of serum 11-KT in males than in females (Nakamura et al, 1989(Nakamura et al, , 1994Cardwell & Liley, 1991a,b;Cochran & Grier, 1991;Kime et al, 1991;Godwin & Thomas, 1993). Also, in some fish, there is higher gonadal biosynthesis of 11-oxygenated steroids in males than in females (Reinboth & Becker, 1984;Hourigan et al, 1991;Latz et al, 1991;Yeung et al, 1993).…”