Well, I guess we have X's "problem" solved -- I've been giving him the 
ProBios like the vet told me to do ..... his manure is normal (even when we 
ride) ...... everything looks OK and the vet has given him a clean bill of 
health.
    NOW, it COULD be a combination of neither of us being nervous together 
anymore ... PLUS the ProBois ...... don't really know but I'm sure happy that 
he isn't sand colicing or anything (the vet took a sample of his manure and 
had it checked).  Of course we'll never know for sure unless we had him 
x-rayed ..... but, things have smoothed out and he even LOOKS better now.
    I hope that's it now.
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