Studies on the Oxygen Consumption and Water Metabolism of Turtle Embryos

Abstract

As a result of the early work of Bohr and Hasselbalch and the later experiments of Murray and others there is available a considerable body of information concerning the respiratory exchange of the chick throughout its embryonic life and, although vertebrate groups other than birds have been less extensively investigated, the respiratory characteristics of the embryos of various fishes and amphibians are also fairly well known. Only two investigations of the respiration of reptilian embryos have been reported however, and these deal with but a few stages.Bohr (1904) carried on some experiments with the eggs of the snake, Coluber initi'i.r, and found a decrease in respiration intensity with increasing age. The respiratory quotient as determined by Bohr was about 0.9 at all of the stages studied.Zarrow and Pomerat (1937) studied four eggs of the Green Snake (Liopcltis z'crnalis) which were in late stages of development and also investigated the respiration of the young after hatching. They report that the absolute gas exchange of the eggs was of the same order of magnitude as that of the young snakes but the respiratory quotient of the hatched animals was significantly greater than that of the embryos.

Growth and oxygen consumption in embryonic and early postembryonic development of European pond turtle Emys orbicularis (Reptilia: Emydidae)

“…A similar dynamics of oxygen consumption during embryogenesis was previously reported for other turtle (Lynn and von Brand, 1945;Ackerman, 1981b;Booth, 1998), crocodile (Thompson, 1989;, and lizard species (Thompson and Stewart, 1997;Booth et al, 2000). No deceleration in oxygen consumption increase was observed in snakes prior to hatching (Dmi'el, 1970;Black et al, 1984;Thompson, 1989;Thompson and Russell, 1999b).…”

“…Embryonic weight of European pond turtle demonstrated an S-shaped increase during embryonic development similar to that of other turtle species: Kinosternon subrubrum, Terrapene carolina, Chelydra serpentina, Chrysemys picta (Lynn and von Brand, 1945), Chelonia mydas, Caretta caretta (Ackerman, 1981a), and Chelydra serpentina (Birchard and Reiber, 1996). In certain representatives of the class Reptilia such as snakes and certain lizards, the embryonic weight steadily increased during the whole embryogenesis without a prehatching deceleration (Clark, 1953a;Dmi'el, 1970;Thompson and Russell, 1999a;Nechaeva and Turpaev, 2002).…”

Effects of low‐oxygen conditions on embryo growth in the painted turtle, Chrysemys picta

“…picta (Lynn and Von Brand 1945;Packard et al 1983;Peterson and Kruegl 2005). Our results suggest that critical windows of sensitivity to hypoxia are narrower, at least with respect to overall growth of embryos.…”

“…picta reaches peaks in rates of growth and O 2 consumption during the last third of development (Lynn and Von Brand 1945;Peterson and Kruegl 2005). During this time, decreased O 2 consumption due to hypoxia likely causes reduction of embryo growth, as demonstrated in other emydid turtles (e.g.…”

<b>Chemical characteristics and thickness of <i>Podocnemis expansa</i> post-hatching eggshells (Testudines, Podocnemididae)

“…Cox et al (1984) evaluated the chemical composition of Squamata eggshells and detected that protein concentration gradually decreased during incubation. Changes in the levels of protein in the eggshell may also lead to changes in bound calcium (Cox et al, 1984 of gas and liquids (Lynn & Brand, 1945;Osborne & Thompson, 2005). Crude fat is one of the elements that contributes with this function.…”