I have heard of a parasite being in salmon and trout. I think this is a article on it.
http://www.doggienews.com/2007/11/sa...se-in-dogs.htm It might just be for raw fish. My husband and I are also fishermen. Our freezer is packed with mostly saltwater fish, albacore, mahi mahi, yellow tail, and yellow and blue fin tuna. Unfortuantly many of the large peditory fish have high mercury counts so I can't feed it very often even to myself. I do need to empty the freezer to be ready for our next long range trip. We do fish fresh water but mostly for Large mouth Bass. We do release them.
My dogs do love fish. I even by cans of Sardines to add to my picky dogs food. It is high in Omega 3. Just one sardine is all I need to get them to eat.