Augusta,
 
I am sure that many folks will to respond to you regarding the extreme
likelihood of adrenal disease.  This is one of the most common ferret
disease, your fuzz-butts are ~middle-aged, and your boy has one the most
commonly reported symptoms (after above-the-tail hair loss).  But, his
symptoms don't mean that HE has the disease!  With adrenal disease, sex
hormones can get way out-of-wack which can cause male aggression or
return-to-male-intact-sexual-behavior, even if the FEMALE has the screwy
hormone levels!  There is much information available about this disease
(start at http://www.afip.org/ferrets/index.html), and there are many
possible symptoms, although the disease can be asymptomatic until fatal
complications arise, so don't put this off.  Please have _BOTH_ ferrets
checked at the most ferret-knowledgeable vet you can find, and get a
second opinion if the first vet doesn't plan to surgically treat or
medicate whichever ferret is suspected to have the disease.
 
My fixed male ferret, Sherlock, (age unknown-guessed at ~7?) exhibited
_just_a_few_ return-to-male-behavior episodes in February.  Both my
ferrets got checked by our vet, and since then we were watching for
additional symptoms to figure out who had adrenal disease.  No other
adrenal diseases symptoms developed in either ferret for months, and
Sherlock completely stopped the return-to-male-behavior!  Just recently
my female, Samantha's (age also guessed at ~7) vulva became somewhat
enlarged, so we went back to the vet and the vet & I now think Samantha
has the disease (although I am still looking for more syptoms from him,
as both could have it!).  Samantha will undergo surgery to locate and
remove the diseased gland(s), then I will keep her on a supplement to
help balance adrenal gland function.  I use Azmira's "Stress & A'Drenal
Plex." You may not want to start the supplement until you are _sure_
which ferret has the disease, just in case it helps enough to delay the
onset of symptoms essential for diagnosis!  I had been giving it to both
of mine after the onset of symptoms in February, but I eventually stopped
when months later no other symptoms were evident.  10 days after taking
them off the supplement Samantha's vulva enlarged!  I am not sure that
this time correlation is based on causation.  I had been giving it to my
last ferret with confirmed adrenal, and it didn't diminish his symptoms,
although his disease had asymptomatically progressed farther them any of
us knew at the time.
 
Of the last 5 older-ferret rescues I have adopted, 2 are still with me
and 1 has adrenal disease, and 3 have passed and 2 of them had adrenal
disease.  Get your little ones to the vet, and give your ferrets a little
snuggle from me!  Best of luck.  I am not a vet.
 
Jenny
[Posted in FML issue 4182]