Years past I was never interested in indoor birds... Fast forward, get ducks, chickens and turkeys and all feathered friends are awesome. I sit out on my deck and watch the wild birds with a whole new interest.
Most chicken feed has fishmeal. Hopefully manhaden, which is the best.
Unfortunately, I've seen the same thing.
Guilty. For the vast majority of nutritional issues either canned pink salmon with some boiled or scrambled eggs or raw beef liver with the same eggs.
Canned pink salmon is loaded with vitamins, protein, amino acids, omega-3/6 fats, etc. Eggs have the perfect balance of amino acids for a bird even though the protein is pretty low. Combining the two is a good approach to first aide dietary needs. Raw liver lacks the fats and has a higher concentration of B vitamins and the rest of the goodies. So again paired with eggs is a good think.