Sex differences in circulating steroid hormone levels in the red drum, Sciaenops ocellatus L
Steroid profiles of cultured and captive red drum (Sciaenops ocellatus L.) were investigated to evaluate the potential use of circulating sex steroid levels as a tool for gender identification in this species. Cultured 18-month-old fish were maintained on a 120-day shortened photothermal cycle to in...
Saved in:
Published in | Aquaculture research Vol. 37; no. 14; pp. 1464 - 1472 |
---|---|
Main Authors | , , |
Format | Journal Article |
Language | English |
Published |
Oxford, UK
Oxford, UK : Blackwell Publishing Ltd
01.10.2006
Blackwell Publishing Ltd |
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | Steroid profiles of cultured and captive red drum (Sciaenops ocellatus L.) were investigated to evaluate the potential use of circulating sex steroid levels as a tool for gender identification in this species. Cultured 18-month-old fish were maintained on a 120-day shortened photothermal cycle to induce precocious maturation. Additionally, wild-caught fish were maintained in captivity under simulated natural photothermal conditions from late spring to early fall. Circulating 11-ketotestosterone (11-KT) levels were significantly higher in males compared with females during the early stages of gonadal growth in both cultured and captive fish. Plasma testosterone (T) levels showed a similar trend; however, the differences were significant only when males were already producing sperm. 17β-estradiol (E2) concentrations were low in males and females before gonadal recrudescence but increased significantly with the progression of vitellogenesis in females. These results show that a test using a minimum concentration of circulating 11-KT could be developed to differentiate between sexes in the early stages of gonadal maturation in red drum. Moreover, plasma E2 concentrations could be used to identify vitellogenic females. The two steroids considered together could help avoid possible error in gender identification due to unusually high levels of certain steroids encountered in some individuals. |
---|---|
Bibliography: | http://dx.doi.org/10.1111/j.1365-2109.2006.01583.x ArticleID:ARE1583 istex:AA79C6868FEACF9F214ECC8ABA1B222B3F66131F ark:/67375/WNG-F3TZ51XV-P Montana Water Center, Montana State University, 101 Huffman Building, Bozeman, MT 59717, USA; E‐mail * Present address kucherka@montana.edu ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 1355-557X 1365-2109 |
DOI: | 10.1111/j.1365-2109.2006.01583.x |