Many cold-blooded reptiles enjoy snacking on egg shells to supplement their calcium intake. The two most common groups that exhibit this behavior are turtles and lizards.
Rabbits
Rabbits are one of the most common mammals that eat eggshells. In the wild, rabbits will eat eggs from bird nests as a source of protein and calcium. The eggshells provide rabbits with important minerals like calcium that are necessary for their health and growth.
Rabbits have strong teeth that allow them to crunchy through the shells with ease.
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