So do you want specifics or just a quick overview?
Uglygreen is correct on the salmon carcases going back for recycling. Hatcheries feed dry and moist pellets to the fish. with the pellet being 65 to 85% fish. Other ingredients are blood meal, bone meal, wheat or other grains, vitamins, and medicins for medicated feed. They also in the private industries add dye to color the meat of the fish. And the Purina Trout chow use to be a mainstay for the private fish farms in Idaho. Worked two yeas over there rasing everything from trout,catfish,talapia,sturgeon,and Gators. :grin:
Hope this helps. :cheers:
Hagen