Some ferrets do take a while to bounce back from ECE, so I wouldn't be
overly concerned at this point - the worst is certainly over.
 
There are three points that I would like to address from your post -
 
1) If the stools are solid black - that might be something to examine in
more detail - are you currently giving any medication, such as Pepto-Bismol
(which may turn the feces black)?  Black stools suggest gastric bleeding
and I am wondering if he might also have a gastric ulcer that is impeding
his recovery - does he grind his teeth during feeding?
 
2) Have you given any medication within the last thirty day, such as
prednisione.  A month after infection, I often suggest a low-dose of
prednsione for a couple of weeks to ferrets who are not putting weight
back on.  These ferrets often have a profound inflammatory disease going
on as a result of the infection, and a low dose of prednisone may take
the edge off of it.
 
3) Heat is certainly a stressor in ferrets - it would be helpful to note
what the temperature actually is back in there, and if any of the others
are having any problems.  A solution may be to move the cages into a
cooler area of the house during the warmer months.
 
With kindest regards,
Bruce H. Williams, DVM, DACVP
 
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[Posted in FML issue 3446]