I've been feeding raw for 4 years now. I feed the whole fish, usually frozen Tilapia, but yes, head, eyes, spine, etc. I use wire cutters to remove the large dorsal, pelvic and anal spines in the fins, as I don't want to risk my dogs not being able to digest them. They also are thick and sharp enough that I'm afraid they'll puncture my dog's mouth as they try to chew on them, frozen or thawed. But they get the entire fish otherwise, to include all the organs, etc. Never had a problem, and they love love love raw fish!