I have no doubts there are quite a few multi generation inbred animals out there. Unfortunately there is no real way to know unless you produce everything yourself. Even then do you know with certainty where your original snakes came from. The point is to not perpetuate the scenario and try and put new blood in your lines. I would even do something like trade straight across for the same animal just to get new blood (ie, Mojave female for Mojave female).
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