1. Calcium Supplement: Eggshell calcium is a natural and cost-effective source of calcium. It is often used as a calcium supplement in animal feed to ensure proper bone and skeletal development. Animals like poultry, swine, and even some companion animals like dogs and cats require adequate calcium intake for strong bones, eggshell formation, and overall health.

2. Phosphorus Balance: The calcium to phosphorus ratio in animal feed is crucial for proper growth and metabolism. Eggshell calcium can help maintain the right balance between calcium and phosphorus, which is especially important in poultry and swine nutrition.

3. Improving Egg Quality: In poultry production, providing eggshell calcium to laying hens can enhance the quality of eggshells. This is important because eggshell quality is directly related to the health of the bird and the market value of the eggs.

4. Eggshell Pigmentation: In some cases, eggshell calcium is used in the feed of certain poultry breeds to enhance eggshell color, which can be desirable for specific market demands.

5. Alternative to Other Calcium Sources: Eggshell calcium can serve as an alternative to other sources of calcium, such as limestone or oyster shell, providing flexibility in feed formulations.