Do bear in mind that not all horses will tolerate sheep and some are killed by trying it, so if you do put them together, initially run an electric tape across the field a little was from the fence/hedge, so the sheep can take refuge in that area if the horse charges it. Depending on temperament and the behaviour you observe, you might then be able to remove it, but if not it should stay and will work well. I did this as I have a horse that cant share a field with anything (very dominant and kicks everything into the middle of next week), altho he has a pony over the fence to talk to. By using the electric refuge tape the sheep could duck under neath and they shared ok.