I have no experience with males so I cannot provide any insights. All my ferrets have been female, all intact and all less than 16 weeks when I got them. Bearing in mind that females come into season in the first spring after birth and the problems caused by early neuter/spay I leave it as long as possible, but no later than the end of February (just to be sure). Tony (not a vet), Sugar and Suki. In memory of Sally and Sue. [Posted in FML 5686]