Maybe this is why even though the study was done on chickens, feeding growing chicks with Bovine Colostrum added to the mix proved very benefifical in a studyI don't find it work at all. Full disclosure I do have one hyacinth Heidi that still eats a few pellets but everyone else eats real food. If you have a pretty good understanding of nutrition then you shouldn't have any problem. I normally don't give my birds vitamins unless there is some reason for me to, most of the time problems can be corrected with the right foods.
Want them to have great feathers, feed them eggs. Mine eat scrambled and boiled on a regular. Mine also get small amounts of animal protein. I make sure they get a little each morning and a little each night. They don’t always eat it but it is there if they want it. In the morning its usually one of the following, eggs, cottage cheese, cheese or plain greek yogurt. In the evening it is usually whatever meat I am preparing for supper. The size of the bird determines the portion, they don’t need a whole lot. My birds eat dairy all the time, cottage cheese, cream cheese, hard cheese, yogurt, kefir, butter, pudding (occasionally) and on occasional sip of milk from a bowl of cereal.
I sprout all kinds of things I buy spouting blends off Amazon, the health food store along with mung beans and popcorn right off the grocery store shelf. I put sprouts and veggies in breads I make for them. There are books on sprouting for parrots I have a couple if you do a google search they should come up.
All my birds have good feathers, they don’t have any health or behavioral problems and all are sexually mature yet I have no egg layers or hormonal problems.
Love Dr. Jason Crean here is his website Welcome
Another favorite of mine on nutrition Dr. Robert Lustig