Cox D L, Koob T J, Mecham R P, Sexton O J
Comp Biochem Physiol B. 1984;79(3):481-7. doi: 10.1016/0305-0491(84)90409-7.
Eggshells of the skink, Eumeces fasciatus, and of the rough green snake, Opheodrys vernalis, contain 28-40% of total shell mass as calcium at oviposition. After incubation, both calcium concentration and content were reduced 17-41%. Protein accounted for 33-65% of shell mass in Eumeces and Opheodrys eggshells at oviposition. Reductions in protein concentration and content from 22-86% following incubation were observed. Comparing amino acid compositions of eggshells collected following oviposition with those collected from the same clutch after hatching reveals similarities among all eggshells except those of Eumeces from Michigan which lack desmosine and isodesmosine. Concentrations of desmosines in eggshells from Missouri and Michigan Eumeces appeared to decrease following incubation by 49.7% and 12.2%, respectively. Although neither the mechanisms involved in apparent losses of calcium and protein, nor the fate of the mobilized materials are known, possible pathways for mobilization of eggshell constituents are outlined and their pertinence to the physiology of squamate eggs and the evolution of viviparity in reptiles is suggested.
四线石龙子（Eumeces fasciatus）和绿瘦蛇（Opheodrys vernalis）的蛋壳在产卵时，钙含量占蛋壳总质量的28 - 40%。孵化后，钙浓度和含量均降低了17 - 41%。在四线石龙子和绿瘦蛇的蛋壳中，蛋白质在产卵时占蛋壳质量的33 - 65%。孵化后，观察到蛋白质浓度和含量降低了22 - 86%。将产卵后收集的蛋壳氨基酸组成与同一窝卵孵化后收集的蛋壳氨基酸组成进行比较，发现除了密歇根州的四线石龙子蛋壳缺乏锁链素和异锁链素外，所有蛋壳之间都存在相似性。密苏里州和密歇根州四线石龙子蛋壳中的锁链素浓度在孵化后似乎分别降低了49.7%和12.2%。尽管目前尚不清楚钙和蛋白质明显损失所涉及的机制，也不清楚被动员物质的去向，但本文概述了蛋壳成分动员的可能途径，并提出了它们与有鳞目卵的生理学以及爬行动物胎生进化的相关性。
