You're welcome... now since I'm trying to read between the lines... your stallion has bred before but never to a mare that has not been a part of his/your herd?
Did I read that right? I'm wondering, which is why I ask these questions, what experience you have in breeding stallions to mares... not the reverse. There is a difference. As the stallion's guard you'll need know a tad more about putting him together with mares you know little or nothing about personally.... other than if she is healthy. A fine stallion, capable of breeding well for years, may be inhibited severely by an encounter with certain mare behaviors... not only during the cover of the mare, but for time to come. Any stallion who is capable of pasture breeding without injury to the mares is worthy of particular care. Any mare incapable of responding in kind to Gentleman Jim needs a close eye kept on her.