It's been known for years that ferrets do NOT get human rhinoviruses
(colds).  They DO get some of the same bacterial infections we get and
they do get influenza, and can trade these back and forth with humans.
(This knowledge is why they are used in labs in testing flu vaccines but
not used to test cold preparations; there's actually a decent base on
what assorted lab animals can and can't get due to those people needing
that info for such work.) It is not unusual for a human to think that a
mild sinus infection or a mild case of influenza is a cold.
 
Keep an eye on the ferret.  If you are given cause for concern DO go to
the vet because secondary infections do happen at times and they can hide
pneumonia well till they are incredibly ill.
 
Do NOT use OTCs (over-the-counter) preparations unless your vet okays a
specific one.  Every influenza season there are sad stories of ferrets
who have died because they were OTCs which are safe for humans but
damage or kill ferrets.  A common one is serious liver damage from
acetominophren (I can never spell that off-hand since we won't even have
it in house).  To check on this and on them not getting rhinoviruses look
the medication up in the Complete Archives of the FHL for vet replies
(See below my signature.), or in the archives of the Ferret Mailing List
at http://listserv.cuny.edu/archives/ferret-search.html (a very useful
resources whose addy is in the header of every FML).
 
Coughing or wheezing, or both warrant a chest x-ray, and often also an
ultrasound.  They can be brought on by infection such as pneumonia, by
cardiomyopathy, by ascites from other causes, etc.  It IS possible for a
ferret to have severe pneumonia and pleurisy and NOT have a vet be able
to tell that from listening.  We've been there with one who just had a
mild cough.  The x-rays scared the vets there when they saw them.
 
An enlarged belly could indicate ascites which can be caused by multiple
things that also can cause the other symptoms you describe.  In this
situation I definitely would have a chest x-ray done, very likely
followed by a chest ultrasound (perhaps an abdominal ultrasound as well
depending on blood test results), would have a CBC with Chemistry Panel
done, and if the nodes are up would have a node pulled for biopsy.
Possible causes of ascites included but are not limited to:
cardiomyopathy, A/V Heart Node Block, lymphoma, kidney disease, liver
disease, etc.  You will find many things written by ferret expert vets
and those with long ferret experience at the sites below to help with
treating such things.
 
Sukie Crandall
Recommended on-line health resources:
http://www.smartgroups.com/groups/ferrethealth
http://fhl.sonic-weasel.org/
http://www.ferretcongress.org  (Critical References)
[Posted in FML issue 4033]