Literaturdatenbank
Literaturdatenbank |
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Packard, G. C., & Packard, M. J. (2002). Wetness of the nest environment influences cardiac development in pre- and post-natal snapping turtles (chelydra serpentina). Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology, 132(4), 905–912.
Added by: Admin (14 Aug 2008 20:36:26 UTC) |
| Resource type: Journal Article BibTeX citation key: Packard2002a View all bibliographic details  |
Categories: General Keywords: Chelydra, Chelydra serpentina, Chelydridae, Habitat = habitat, Nordamerika = North America, Schildkröten = turtles + tortoises, Zeitigung = incubation Creators: Packard, Packard Collection: Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology |
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| Abstract |
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We dissected hearts from near-term embryos and hatchlings of common snapping turtles (Chelydridae: Chelydra serpentina) whose eggs had incubated on wet or dry substrates, and then dried and individually weighed the heart and yolk-free carcass from each animal. Hearts and carcasses of prenatal and neonatal animals grew at different rates, and the patterns of growth by both heart and carcass differed between wet and dry environments. Hearts grew faster, both in actual mass and in mass adjusted for variation in body size, in embryos and hatchlings whose eggs were incubated on dry substrates than in animals whose eggs were held on wet media. This finding is consistent with a hypothesis that embryos incubating in dry settings experience hypovolemia secondary to dehydration and that enlargement of the heart compensates, in part, for the associated increase in viscosity of the blood. Embryonic turtles seemingly exhibit the same plasticity and response that would be expected from other vertebrate ectotherms subjected to the physiological challenges associated with desiccation and an associated reduction in blood volume.
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