The grain is the teeth of our pigeons. The more well the food is ground, the more nutrients our pigeons can extract from it.
This is one of the reasons why we should not give Redstone or Grit with Redstone to our athletes, and certainly not during racing season. Redstone is crushed with the food and is of no use to our animals.
Most types of gravel available on the market contain little to no gravel and oyster shells because they are relatively expensive. These are exactly the ones you need to have. Pigeons ingest them and stay in the stomach for a longer period of time to help grind the food, resulting in greater absorption of the nutrients in the food. This contrasts with red stone, limestone, etc. These are crushed and this is the reason why pigeons continue to eat them. They also do this to absorb calcium. The problem is that the pigeon's body does not absorb this calcium due to an incorrect calcium-to-phosphorus ratio. It is therefore quite normal that pigeons consume and need very little of our anise grains.
Usage: Provide a very small amount of fresh food in a pigeon jar every day.