I'm racking my brain for how we covered spitters at Harlan's. It was back in the early 1990's though, so will take a bit to remember details.
As best I recall we used a bumper, positioned mare with head downhill, and she was on a lunge line. As soon as stallion dismounted, she was sent off at a smart trot and was kept moving for at least 15 mins. I know we changed feed and water routines for spitters too....just can't pull up the details.
What is a bumper?? A bolster pillow placed between the mares rump and the stallion. If being used to encourage better penetration, we pulled it after he was mounted and stable. He'd then move forward forcefully, thinking the mare was moving off. He also used it when he wanted a better chance for a filly, but left it in place. I was told they had better than an 80% success rate doing this. In the time I was there, the 3 mares we used bumpers on had fillies.
