Sources of calcium for embryonic development in eggs of the snapping turtleChelydra serpentina

✍ Scribed by Packard, Mary J. ;Short, Terry M. ;Packard, Gary C. ;Gorell, Thomas A.

• Book ID: 102890435
• Publisher: John Wiley and Sons
• Year: 1984
• Tongue: English
• Weight: 834 KB
• Volume: 230
• Category: Article
• ISSN: 0022-104X
• DOI: 10.1002/jez.1402300111

✦ Synopsis

Flexible-shelled eggs of snapping turtles (Chelydra serpentina) were analyzed for calcium content at different times in incubation to determine sources of mineral for developing embryos and to characterize the pattern of its mobilization. Yolk and albumen of freshly laid eggs contained 11.70 and 0.16 mg of calcium, respectively. Almost all calcium was withdrawn from the yolk during incubation, but this calcium was not sufficient to satisfy requirements of embryos. Calcium contained within eggs increased to 27 mg between oviposition and hatching owing to mobilization of approximately 15 mg of calcium from the calcareous eggshell. Thus, embryonic snapping turtles obtain slightly more than half (56%) of the calcium required for development from the eggshell, with the remainder (44%) coming from stores present in the yolk at oviposition.