Blood Tests on Endurance mare

["G & J Thom" <thomlabs@netbistro.com>]

Hello all,

I took my 15 yr old endurance mare to the vet to see
why she is acts like she has a belly ache or is beginning
to tie up whenever I ride her for more then 1/2 hour.  Had
already had the chiro check her back and saddle fit.

The vets did the works the only thing that showed up in the
blood work was a increase in the muscle enezme (sp) 
especially odd since the mare had not been ridden in over 10
days.  Am still waiting for the mineral and selenium tests
to come back they seem to be taking forever.  Was wondering
if anyone had any thoughts on what might be happening.
I rode this mare over 700 miles last year with no problems.

Thanks
Julia