Growing up my dad raised Norweigan Elkhounds and he would pressure-cook the carcasses and heads and feed it to the dogs -- They loved it!

I used to freeze a lot of crab bait to have readily available but my local QFC does all the cutting for a number of stores and gives me buckets of fresh bait free on a moment's notice so I save the freezer space.
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. . . and God said unto them, Be fruitful, and multiply, and have dominion over the fish of the sea . . .