Chicken feed if you want to make your own:

Whole oats - 4 lbs.

Dried Whole or Cracked Corn - 2 lbs.

(whole corn ok for mature birds, may still contain some shuck, cracked corn easier for small birds to digest, also crumbles keep em busy and not picking at each other)

Sun Flower seeds - 2 lbs.

Split Peas - 1 lb.

Flax Seed or Chia Seed - 1 lb.

Increase or decrease as needed.

We recently had to lay our horse down and had a full can of senior horse feed and alfalfa pellets. We used that to feed our two ducks and chx. We slightly wet it and mix it around in a bucket to make it moist throughout. Works great also