The British Herpetological Society

The Herpetological Journal is the Society's prestigious quarterly scientific journal. Articles are listed in Biological Abstracts, Current Awareness in Biological Sciences,Current Contents, Science Citation Index, and Zoological Record.

The 2017/18  impact factor of the Herpetological Journal is 1.268

pdf 03. Embryonic use of energy and post hatching yolk in the gray rat snake, Ptyas korros (Colubridae)


Open Access


Authors: Xiang Ji And Ping-yue Sun

Abstract: Female Ptyas korros from a population on Dinghai, Zhoushan Islands, in eastern China, produced one clutch per breeding season. Clutch size varied from 7 to 1 4, and was positively correlated with female SVL. The duration of incubation at 30 ± 0. 5 °C averaged 54. 7 days. Dried shells from freshly laid eggs averaged 30.0% of the entire egg dry mass. Egg contents of the freshly laid egg contained higher quantities of dry material, non-polar lipids and energy than did newly hatched hatchlings. Shells from freshly laid eggs contained higher quantities of ash than did those from hatched eggs. During incubation, approximately 77% of dry material, 54% of non-polar lipids and 69% of energy in the egg contents of freshly laid eggs were transferred to the hatchling. There were inverse relationships between carcass dry mass, post-hatching yolk dry mass and fat body dry mass for hatchlings sampled immediately after hatching. Post hatching yolk could be used to support subsequent growth of newly emerged young, as indicated by significant increases in the carcass dry mass and SVL of hatchlings during their first days of life, following the depletion of post-hatching yolk

Keywords: Colubridae, Ptyas korros, incubation, egg, hatchling, post-hatching

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