After 25 years, I had finally had my first full uterine prolapse on a calf I had to pull. I didn't realize at the time the the most critical thing for survival is to keep the cow from moving due to the likelihood of tearing blood vessels that could result in them bleeding out. So important note to those who haven't dealt with this yet - if it happens to you, it's not like a rectal or vaginal prolapse - DONT MOVE THE ANIMAL while you're waiting for the vet. Just a little something I wish I new a couple weeks ago.