It only seems like the past 15 years or so, that people started talking about gluten intolerance and gluten free diets. Well what’s good for humans could be good for dogs. I just read about a lady called Tena Norman (in the United States of course) who has set up a company selling gluten free treats for dogs.
I don’t know anything about dog physiology, but I do know a bit about human psychology. If their pet appears under the weather they will happily spend money looking for a solution. And if gluten free diets work for some humans, maybe they’ll work for dogs too. If you’re looking to break into the pet food/treat market, this could be a profitable angle.