Foods With Calcium For Chickens. You can either leave them in big pieces or you can crush them down a bit. The most common sources of calcium for chickens is limestone.
The recommended level for calcium is 1 or below for these birds. The calcium content of chicken bone from a slaughter plant was about 55 g Ca100 g. Giving young chickens more calcium than their fluffy bodies can absorb causes kidney damage and decreases their lifespan.
A All foods listed are assumed to be in nutrient-dense forms.
If you have your own leftover oyster shells that you want to offer to your chickens start by cleaning them well. Layer feed has up to four times this amount so you should never feed it to birds under 18 weeks. Sardines in oil canned. Some people also clean and crush their used egg shells and feed them back to their hens.