the general consensus is that the issue isn't with the dubias themselves, but more what is being fed to the dubias because of how they retain the uric acid. Most of the information that is available on their feeding is from die hard reptile owners, but not much as far as official scientific studies
A reason your vet might not see it much could depend on the life stages of dragons he sees (along with the quantity.) Younger dragons obviously eat younger roaches. Younger roaches have been shown to have significantly lower UA levels than older roaches, due to UA building up over time. Adults (or large dragons that obviously ate way too many feeder insects to become full grown at 9 months old) that eat older/larger dubias are where we see it most often.
It is the high levels of protein in a dubia's diet that increase their UA levels, not any specific food. Although casein protein has been shown to almost double UA levels over other sources of protein (no milk protein in your chow mix!) A low protein diet will help lower roaches UA levels. Here is a post of mine from another thread on the topic:
Even when fed a low protein diet, roaches still have high levels of Uric acid in their bodies. This is because roaches, unlike many other insects, do not expel their uric acid, they hold onto it for various biological reasons that are a bit more in depth than this needs to be. It stays in their body, for further use, and can be converted back into protein nitrogen when needed. But, they can't get rid of it like other insects can. When roaches are fed a high protein diet, they create even more uric acid. This can get to the point where the roach will actually die from it's built up uric acid levels.
A low protein diet for the roaches is the best middle ground, but I would be more cautious on what exactly your supplier considers low protein. Many people feed their roaches a dog/cat chow mixture. Most dog food is 18-25% protein. So with that train of thought, would you consider half of that to be low protein? Say 9-12%? Still, according to one biochemist who oddly enough is also a roach expert, he says the magic number he shoots for with roaches is 4% protein.
So the biochemist roach expert thinks 4% is a good number. I've found that getting too low effects breeding programs (not an issue if you're just buying roaches) Which is why I settled 6%. I've had decent success aiming for that percentage.
Obviously there is more than one contributing factor to gout in dragons, a major one being
hydration, but there really is no benefit in what i've seen to feeding roaches a high protein diet.
-Brandon