I have a neighbor with 80 acres whose property borders about 1/8 of my place. He is constantly running heiffers in there with no bull, and his heiffers are usually coming into heat, or go into heat, while on that particular pasture. If he had a bull, both his heiffers and my bull would be better off for obvious reasons.
His fences are in poor condition and he refuses to repair them, so after making repair upon repair, I finally said I'm done fixing the mutual fence alone. His heiffers get onto my place every now and then and ocassionally, my bull goes over and visits his heiffers for a little romance.
We have a Charlais bull and I have no intention at all of getting rid of him. I guess it depends on the situation and the neighbor, regarding keeping the bull or not, but putting heiffers in heat, without a bull, in a pasture next to a pasture with a bull with weak fences, is not real smart anyway. No matter the breed of the bull, that is just asking for trouble, for both parties, especially when those "fluzzie" heiffers flaunt it at the fence line constantly!!
I think this neighbor does it on purpose anyway since he has repeatedly stated what a good looking bull we have and how good looking the calves are that he sires! I look at it as "Country Romance with a wink!"