For the female (jill) ferret it is essential unless you want to breed from her. Ferrets are induced ovulators, once a jill comes in season she will stay in season until she is mated. Apart from the swollen vulva becoming sore and damaged, the high levels of oestrogen cause anaemia.
The alternative is an injection; given at the beginning of the year there is a good chance of it suppressing the season for the whole year. Used repeatedly there is a risk of womb problems (pyometra).
Using a vasectomised male (hob) exposes the jill to very rough treatment at the time of mating, as well as the pyometa risk. In my opinion, this is not acceptable now there are alternatives.
the uncastrated hob is liable to be aggressive to other ferrets and difficult to handle.
The uncastrated hob has a greasy coat and a highly pungent odour which clings to anything it comes in contact with. You really don't want him as a pet!
PRICES Spaying a female £48 Castrating a male £40
Although the anaesthetics used for ferrets are not licensed for that species, they are widely used and very safe. Ferrets take surgery well and recover quickly.