red paw - if you're breeding, please read
http://www.cavyspirit.com/breeding.htm
Putting unaltered males and females together is a very bad idea. Of course they are going to fight esp. if they are not neutered. Please separate them asap until you can neuter the males.
If the sows give birth with the males still there, they can be backbred. It's very hard on their bodies. Also, the babies may be trampled if there is fighting going around. Stress is bad for pregnant sows.