Literaturdatenbank
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Lance, V. A., Grumbles, J. S., & Rostal, D. C. (2001). Sex differences in plasma corticosterone in desert tortoises, gopherus agassizii, during the reproductive cycle. Journal of Experimental Biology, 289(5), 285–289.
Added by: Admin (17 Aug 2008 17:23:52 UTC) |
| Resource type: Journal Article BibTeX citation key: Lance2001 View all bibliographic details  |
Categories: General Keywords: Blut = blood, Fortpflanzung = reproduction, Gopherus, Gopherus agassizii, Habitat = habitat, Nordamerika = North America, Schildkröten = turtles + tortoises, Testudinidae Creators: Grumbles, Lance, Rostal Collection: Journal of Experimental Biology |
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| Abstract |
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Blood samples from 30 female and 20 male adult desert tortoises, Gopherus agassizii, were collected at monthly intervals during the annual reproductive cycle (April to October). Plasma corticosterone and the sex steroids in each of the samples were analyzed by radioimmunoassay. Mean corticosterone levels in males were significantly higher than in females (P < 0.001) in every month. Male tortoises showed a marked seasonal pattern in plasma corticosterone with a highly significant peak in July, August, September, and October that corresponded with a similar peak in plasma testosterone. Testosterone and corticosterone in the male showed a highly significant correlation (P < 0.0001). The pattern of corticosterone in the female was less marked, with a significant peak in May during the mating and nesting season, but no association with the peak in estradiol in late summer was apparent. The highest levels of corticosterone in the males were associated with the peak in spermatogenesis and intense male-male combat. These results support similar data from other reptiles that suggest increased glucocorticoid secretion during periods of increased activity and metabolism. Copyright 2001 Wiley-Liss, Inc. Testudinidae
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