I feed Flock Raiser to all my flock but I also feed dried meal worms as an afternoon treat, my Toulouse goose loves them my Embden gander won't touch them.Geese do not need to eat meat in order to get protein. Flock Raiser and Layena use 100% plant protein, no animal products at all, same as all commercial poultry feed.
Like I said, commercial feed uses plant protein and are strictly vegetarian. Plants have protein, and herbivores the world over seem to do just fine without preying on other animals.
I raise Embdens, Americans, Africans, and Chinese geese. None of them fish in my pond, they leave the fishing to the ducks. They dive with their feet in the air to eat aquatic plants. Suggesting that a person needs fish, or some other animal product, to raise healthy geese is just fallacious.