I may be wrong, but the way I read the question was how long to blow during fitting. I would assume we all know you blow a calf completely dry before starting to fit.
So, the length of time to blow is until all the hair has "popped".
A Cow that looks like a Cow, breeds back on time, every time, can calve a 100lb calf unassisted, averages 600lb calves at six months, and has tons of thick straight Hair!
Brent, I personally know the incredible power of Believers' Prayer. Our God is healer and deliverer. I just lifted Keaton up in Prayer, and your family as well, trusting our Savior.
Keep us all informed.