I'm positive salmon does not contain large portions of fat, yeah trout might though when I think about it. However, I would highly doubt either of this fish do as Salmon stop eating when entering freshwater to spawn, there bodies will consume all fat in order to keep swimming to their spawning destination. Trout lose all fat during winter with the lack of food, however they gain it back during salmon season as they consume salmon eggs and salmon tissue until it runs out.
i caught the salmon when they enter freshwater waterways, I caught the trout ice fishing.