Personally, I think it is better to have 1 male for each female. Many people do have their male in with multiple females and it seems to work for them at times. Personally, I would rather have one male focus on one female.
Last year I had a male breed two females. This was done due to my other male not being a mature breeder. I had two litters. But, both had half the litter being slugs. So, I lost out on some babies I think due to this. One the other hand. I did luck out and have two litters..........Where I only would have had one.
But, if I had my choice........I would keep one male with one female only.
John
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"To be the best..........You must lose your mind."