Literaturdatenbank
Literaturdatenbank |
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Blanvillain, G., Owens, D. W., & Kuchling, G. (2011). Chapter 10 - hormones and reproductive cycles in turtles. In D. Norris & K. Lopez (Eds.), Hormones and Reproduction of Vertebrates Vol. 3 - Reptiles, (pp. 277–303). San Diego: Elsevier.
Added by: Sarina Wunderlich (25 Jun 2011 12:41:16 UTC) |
| Resource type: Book Article DOI: 10.1016/B978-0-12-374930-7.10010-X BibTeX citation key: Blanvillain2011 View all bibliographic details  |
Categories: General Keywords: Ernährung = nutrition, Fortpflanzung = reproduction, Physiologie = physiology, Schildkröten = turtles + tortoises Creators: Blanvillain, Kuchling, Lopez, Norris, Owens Publisher: Elsevier (San Diego) Collection: Hormones and Reproduction of Vertebrates |
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| Abstract |
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Reproductive cycles of cryptodire turtles and species from the northern hemisphere have been investigated extensively compared to those of pleurodire species from the southern hemisphere. Radiography, laparoscopy, and ultrasonography have been used on a few species of turtle to describe a diversity of ovarian and testicular cycles. Radioimmunoassays (RIAs), on the other hand, have provided evidence of the dynamic cycling of peptides and steroid hormones within a reproductive season. All turtles are cyclic breeders and show a range of annual and multiannual reproductive patterns—regulated by nutritional status and environmental conditions—which are most often described as prenuptial or postnuptial. These cycles may be seasonally coordinated by an active pineal gland in the brain via melatonin secretion affecting the hypothalamus. Moreover, the steroid hormone cycles can be rapid and dynamic, and steroid hormones stimulate a carefully orchestrated mating receptivity period: a series of rapid ovulations in the case of multiclutched turtles, egg production, and oviposition events.
Added by: Sarina Wunderlich |