There are three types of poultry grit available.
* Oyster Shell grit - which is a source of calcium to help form strong egg shells.
* Layers Grit - which is used for grinding down food but also contains some Oyster shell.
* Growers Grit - which is used for grinding down food, by young birds, pre-egg laying.
In order to form strong egg shells, chickens require a certain amount of calcium in their diet. Most of an egg shell is made up of calcium. These days, with the research that has been done for formulated feeds (available as layers mash or layers pellets), it isn’t so critical to provide oystershell grit because layers feeds contain sufficient calcium, however, it’s cheap and it’s easy to mix some in with the flint grit that they need above so it’s a good idea to provide some, in case they need more calcium.
Oyster shell should always be available to your birds in a strong, all weather container. The container just needs to be sturdy, so it doesn’t get tipped over or filled up with water.