I'm a college undergrad biology student and currently studying developmental biology as part of my curriculum.
I've read a research journal titled, A Novel Shell-less culture system for chick embryo using a plastic film as culture vessels. by Yutakah Tahara and Katsuya Obara, and happened to be interested with this method but stumbled with a question that kept bugging me out of pure curiosity. While reading their journal I encountered a statement
"...250-300mg calcium lactate pentahydrate powder (Showa Chemical Co., Tokyo, Japan) was added to the culture vessels." and they also added distilled water.
The proponents seem to use Calcium lactate pentahydrate as a substitute for the chick's source of calcium. In dev bio class, I've learned that the chick embryo has two main sources of calcium - the yolk and the egg shell. The egg shell contains 94% Calcium carbonate (literally a major source of calcium). I've read that the Chorioallantoic membrane (CAM) is responsible for the mobilization or transport of calcium from egg shell to the chick's circulation -https://www.ncbi.nlm.nih.gov/pubmed/2955074 - and here is where my question starts:
I understand that the proponents used Calcium lactate pentahydrate powder because its soluble in water - making it easier for the chick to incorporate the dissolved Calcium lactate. I also understand that Calcium carbonate is insoluble in water BUT If CAM is responsible for the mobilization of calcium from egg shell to the chick's circulation to form the skeletal structure of the bird, what difference does it make if I use sterilized powdered egg shells as the chick's 2nd major source of Calcium carbonate?
Thank you for taking the time to read and trying to answer my question! It means a lot 😃