16% is what is used for commercial layers raised in confinement and bred for efficient production. It's not made to be optimal for long-term health but to support a lightweight production bird for approximately 1 year of laying life before she's culled without costing the farmer so much that it...
Unless you are raising Cornish X meat birds, chickens will not overeat and, under normal backyard conditions, will do best with free access to their feed at all times when not on their roosts for the night.
It's possible to use a number of rationed feed systems successfully, but it requires a...