Yes I do a quick boil or microwave any fresh fish I give them, because here in San Diego I'm not trustworthy of our local fresh fish as far as germs. I go to a small restaurant supply store call 'Smart and Final' and they have a cheap canned Salmon with softened bones. My dog splits it with the...
Their favorite is Salmon, then tuna. Some liked the mackerel some didn't. They loved it when my neighbor brought over some leftover fish from his fishing trip.