What I hear is that they can get pregnant again quickly after they give birth and that it can be bad for them but i think as long as you have about 1.3 there should be plenty of action for the male.

But I can also see why people would want to give them a break. Maybe get one more male to cut down your recovery period and boost your production? If I was going to do it this way I would only give the time it takes to wean as a recovery period.