Testicular development and plasma sex steroid levels in cultured male Senegalese sole Solea senegalensis Kaup
Testicular development and plasma levels of sex steroids (11-ketotestosterone (11-KT), testosterone (T) and 17,20β-dihydroxy-4-pregnen-3-one (17,20β-P)) were investigated for the first time in cultured male Senegalese sole Solea senegalensis. The germ cell dynamics and gonadosomatic index ( I G) wer...
Saved in:
Published in | General and comparative endocrinology Vol. 147; no. 3; pp. 343 - 351 |
---|---|
Main Authors | , , , , , |
Format | Journal Article |
Language | English |
Published |
United States
Elsevier Inc
01.07.2006
|
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | Testicular development and plasma levels of sex steroids (11-ketotestosterone (11-KT), testosterone (T) and 17,20β-dihydroxy-4-pregnen-3-one (17,20β-P)) were investigated for the first time in cultured male Senegalese sole
Solea senegalensis. The germ cell dynamics and gonadosomatic index (
I
G) were monitored. Based on the relative abundance of the different types of germ cells present, the spermatogenetic cycle was divided into five stages: early (I; spermatogonia (SPG)), mid (II; SPG, spermatocytes (SPC) and spermatids (SPD)), and late spermatogenesis (III; SPC, SPD, and spermatozoa (SPZ)), functional maturation (IV; SPD and SPZ), and recovery (V; SPD, SPZ, and SPG). During summer, fish had stage I and V testes and the lowest values in plasma levels of sex steroids and
I
G. Testicular recrudescence seemed to begin in autumn, as denoted by the first increase in
I
G and in the levels of 11-KT and T, and the appearance of testes at stage II and III. During winter, the levels of 11-KT and T peaked and soon began to decrease, the
I
G slightly declined and the proportion of running males (RM) gradually increased. In spring, levels of 11-KT and T continued to decline, the
I
G slightly increased and the proportion of RM peaked concomitantly with the occurrence of stage IV testes. Plasma levels of 17,20β-P did not change significantly throughout testicular development. Transformation of SPD into SPZ followed a group-synchronous fashion, a phenomenon which parallels asynchronous oocyte development reported in females. This mechanism would be consistent with the observed small quantity of sperm that can be manually stripped at any one time and other aspects of
S. senegalensis reproductive biology. |
---|---|
Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0016-6480 1095-6840 |
DOI: | 10.1016/j.ygcen.2006.02.003 |