Matan, Are you sure she is in heat?  Sometimes adrenal tumors mimic
heat....swollen vulva, aggressiveness.  A blood test specific for ferrets
can be run at the University of Tennessee to test for this.  Don't let your
vet do the cortisol test for dogs and cats, as it doesn't help with ferrets
because ferrets hypersecrete different hormones from their adrenal tumors.
cb
[Posted in FML issue 3450]