Elizabeth,
 
You are right that your ferret does need IMRAB-3 but wrong on the live
virus.  Only a killed virus should ever be used, and only IMBAB-3 is
recognized as effective in a ferret by public officials.  The others might
work just as well, but you might as well be giving them saline as far at the
officials are concerned.  Even with IMRAB, if the officials are called in on
a ferret bite, most states will kill the ferret.
 
Dick B.
[Posted in FML issue 1797]