Gonadal Stage and Sex Steroid Correlations in Siberian Sturgeon,Acipenser baeri,Habituated to a Semitropical Environment |
| |
| Authors: | Heather J. Hamlin Matthew R. Milnes Constance M. Beaulaton Lori C. Albergotti Louis J. Guillette Jr. |
| |
| Affiliation: | 1. Department of Biology, University of Florida, 223 Bartram Hall, PO Box 118525, Gainesville, Florida 32611‐8525, USA and Mote Marine Laboratory, Center for Aquaculture Research and Development, 1600 Ken Thompson Pkwy, Sarasota, Florida 34236, USA;2. Conservation and Research for Endangered Species, Zoological Society of San Diego, 15600 San Pasqual Valley Rd, Escondido, California 92027, USA;3. Mote Marine Laboratory, Center for Aquaculture Research and Development, 1600 Ken Thompson Pkwy, Sarasota, Florida 34236, USA;4. Department of Biology, University of Florida, 223 Bartram Hall, PO Box 118525, Gainesville, Florida 32611‐8525, USA |
| |
| Abstract: | Stages of gonadal development, in association with plasma concentrations of the sex steroids 17β‐estradiol (E2), progesterone (P4), testosterone (T), and 11‐ketotestosterone (11‐KT), were investigated for a single time point during a natural breeding season in 7‐yr‐old Siberian sturgeon, Acipenser baeri Brandt, exposed lifelong to a warmwater environment. Among females, examination of gonadal tissue showed variation in ovarian stage, with 12.5, 47.5, 22.5, and 17.5% of females found at Stages 2 (previtellogenic), 3 (early vitellogenic), 4 (mid‐vitellogenic), and 5 (migratory nucleus), respectively. Although patterns varied among the hormones, plasma concentrations of E2, T, and 11‐KT became increasingly elevated in females as maturation progressed. On the basis of histological criteria, males were classified as either premeiotic (quiescent) or meiotic and 50% of the males sampled were found at each stage. Significant elevations in circulating concentrations of plasma E2 and T were observed in meiotic versus premeiotic males, and there was a rise in plasma 11‐KT concentration that approached significance (P = 0.056). |
| |
| Keywords: | |
|
|
