Question for the trainers/owners-

[GenuineRisk]

-Or anyone who knows more about this than I (which is a lot of people):

From the article on DRF: Mine That Bird Not Certain for the Preakness

"We'll let the horse tell us," Allen, who owns Mine That Bird with Dr. Leonard Blach, said Sunday morning as a light rain fell at Churchill Downs. "We'll run some blood work on him, make sure it's where it should be."

Is doing blood work SOP after a race, even if there's no sign of a problem? What would they be looking for?

I'm not implying anything; I've just never read a quote by an owner after a race stating they were going specifically to do blood work before deciding on a horse's next move.