We are going to breed her momma again this spring, that is if I can get Mack to come out and help. And no:) they can't do it by themselves. We have always halter bred so to keep the stud from getting kicked, or the mare bit. We don't bred the stud often so it's been 2 yrs since he bred one, he may be a bit aggressive.
No way can Mack substitute for the stud.
That would be construed as cruel and inhumane treatment for the mare.
And besides, they would have one ugly baby!