In the past week I have had 2 of my 3 male breeders die. All of my females are healthy as far as I can tell; no wheezing, nice coats, stools are normal, eyes clean and clear. My males were large too around 300g and healthy as well. I keep 2 females per tub in a 7 tub rack system. Temp is around 68 degrees at all times. I clean every 5 days and change water daily. I dont have a gravitational water system just bottles. I use Mazuri Rodent Breeder and they are never out of food. Could my females be killing my males? I dont know what the heck is going on... The thing is neither male showed any signs of foul play. They just looked like they had dropped dead.... My males usually spend about 10-14 days in each tub before being moved into another. Could it be that the ladies get aggressive after a while and off the guys?