Well not exactly what your after but here is a scenario that has worked in the past.
My parents did not buy chicken feed for a year. The chickens free ranged for the majority of their food with only table scraps for supplementation. The chickens would eat up any grain feed that the goats dropped and would eat (when given the opportunity) the turkeys feed as well. They still laid eggs but the production did indeed go down. At least their was no feed cost involved. I wouldn't go that route myself. Feed keeps up their laying as it provides a good balance. Chickens loved the garden and bugs and I guess if there is enough of that they can get by quite fine.
There is plenty of info on this site of those who mix their own feed. So really good info.