We feed our rats and mice dog food and one of our suppliers does too. I think i remember hearing that senior formula dog food has a better nutritional value for them too, but don't quote me there I've also never seen any males really fight to the point of them not being able to stay in the same cage. Honestly I can't remember the last time I saw any of our rats fighting. Though the only breeding we do is from the occasional prego feeder, I think your set up sounds pretty solid.