While we can't replicate a wild diet for captive cockatoos, I give them a varied diet that varies by the day. 3 to 4 times per week they receive fruits and veggies* and have that as an exclusive diet until evening. About an hour before bedtime they are given a treat of Zupreme pellets. During the other days they are given a mix of high quality seed mix with Zupreme. About 3 times weekly they are given whole grain bread, millet, and a small piece of string cheese.
*Fruits and vegetables: Peas, lima beans, garbanzo beans, kidney and pinto beans, black-eyed peas, corn-on-the-cob, yams, sweet potatoes, endamame pods, apple, orange, various melons, pomegranate, banana, pear, watermelon, organic grapes, whole grain spiral noodles, etc.
Not every bird likes all of the above, but each bowl is given stuff they don't like - sometimes after years of refusal they'll try and enjoy something! Most of the birds are free-flight in a large room-aviary, so the adage of "what's mine is mine, what's yours is mine" is operative - and there's never any food-fighting!
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