From what we've seen over the years seedy stools tend to be partially
undigested food, and mucusy strings to be mucus.  Those are not uncommon
responses to a number of things -- from too much fiber or another irritant
in the diet, to an intestinal illness, to colitis, to losing too much of
the helpful bacteria colony in the intestine from antibiotics.  Response
is the same: treat any illness or inflammatory condition causing it, avoid
foods which tend to irritate such as milk or foods with a lot of fiber till
inflammation is down, and help replace the missing helpful bacteria by
giving things like yogurt with live cultures.  Yogurt is digested enough
that there shouldn't be any problem with it, and the flavor will depend on
which ones the ferret likes best.  Since you have been giving an antibiotic
I'd suspect that's the inclusion you need.  Ask your vet in case there is
any counter-indication.
 
Our Meeteetse kept having vaginal infections.  There were several possible
causes: personal susceptibility to such infections, a uterine stump, an
adrenal neoplasia or other adrenal growth causing hyperestrogenism, bit(s)
or ovarian tissue accident left in: the normal things one considers for a
ferret with such problems.  It was an adrenal neoplasia when surgery was
done.  Her vulva never did return quite to normal size but it got close and
she's not had any repeat yet (surgery over a year and half ago, I'd guess).
Adrenal growths can even happen with NO symptoms at times -- have
encountered that.
 
Nothing wrong with learning here, and certainly people should also be
accessing pages like http://www.afip.org/ferrets/index.html ,
http://www.ferretcentral.org , http://www.miamiferret.org, etc.  There is
lot wrong with trying to use the list INSTEAD of a vet, though, and that
happens periodically, sometimes (very rarely) with people saying outright
that this is what they are trying to do.
 
Yes, quarantines and initial vet check-ups (with a stool check, too) for
new arrivals are VERY important.
[Posted in FML issue 2930]