An article of significance from ferretshelters.com:
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   [Posted with permission of ferretshelters.com]
 
Shelter Shock
 
There are many reasons for surrendering ferrets.  Some are good ones, some
aren't.  Most are due to misinformation, or lack of information concerning
ferret needs and care.  Whatever the reason, the effect on the ferret is
the same.
 
Shelter Shock is a very real "illness".  Ferrets over the age of 3 are
especially susceptible.  For ferrets over the age of 5 or 6, it is often
a death sentence.  Shelter Shock is a combination of several problems with
symptoms that begin as deceptively minor troubles but act as catalysts for
each other and merge into a vicious cycle from which there is often no
return.
 
When it becomes necessary to surrender your ferret to a shelter, or give
your ferret to someone else, you should make every possible effort to make
the ferret's environment change LESS ABRUPT.  Visit the shelter or new
home with your ferret several times before letting your ferret go.  The
ferret should get to meet the shelter operator or new owner several times
over a two or three week period.  If you are surrendering your ferret to
a shelter, your ferret should be allowed to spend a few minutes in the
quarantine cage he will occupy later.  Take your ferret's bedding from
home with you for this cage introduction.
 
If the shelter will be feeding your ferret a different food, take some of
the shelter's food home with you.  Mix the shelter food with your ferret's
food at home.  It's much less stressful for ferrets to change to a new
food in a familiar environment.
 
Ferrets "imprint" on the smell and taste of food.  To the average United
States ferret, a mouse does not smell or taste like food, even though
rodents are a ferret's natural prey.  That's the primary reason domestic
ferrets do not survive when they escape.  Escaped ferrets are usually
attracted to outdoor dog food bowls and are often killed by dogs.  A
similar problem is encountered when changing brands of ferret food.  The
new food doesn't smell or taste like food, so the ferret refuses to eat
it.  After several missed meals, the ferret's stomach becomes upset.  A
ferret with an upset stomach is even less likely to eat.  Stomach ulcers
form, infection occurs and a downhill spiral to serious illness or death
begins.
 
If your ferret will have only a water bottle instead of a bowl (or vice
versa), make that change at home also.  Not all ferrets automatically
know how to drink from a water bottle and will dehydrate before the
problem is noticed.
 
Your ferret may contract ECE (Green Slimy Poop Disease) on the visit to
the shelter.  It is infinitely better for the ferret to be treated and
begin recovery from ECE in his old home.  ECE causes stomach upset.  It
can strip the capillary blood vessels from the ferret's intestinal lining
inhibiting the ferret's ability to absorb nutrients from digesting food.
ECE in addition to food change stress is the number one Shelter Shock
killer.
 
Do NOT wash your ferret's bedding before taking him to the shelter or his
new owners.  The ferret's bedding should go with the ferret to his new
home and NOT be washed for at least a week!  It is also helpful to send
an unwashed t-shirt or other article of clothing that you have worn with
your ferret.  Smells are critically important to ferrets.
 
Visit your ferret in his new home.  A short daily visit, or every other
day, the first week is ideal; reducing to two or three visits a week for
the next couple of weeks.  However hard this is for you, it could easily
be a matter of life or death for your ferret.  Even though you may not
have been spending any time at all with your ferret at home, your smell
and presence are still there and that is a vital part of "normal & all's
well" in your ferret's world.  In this way, the shelter staff or new
family gradually replaces you.
 
Abruptly losing all contact with "his" humans can cause serious
depression.  Just like in humans, depression decreases the appetite.  A
ferret that quits eating for any reason is critically ill.  The ferret
metabolism is so fast (4 hours from ingestion to excretion) that appetite
disorders cause secondary medical conditions to erupt very quickly.  A
ferret that goes 18 hours without eating is roughly equivalent to a human
not eating for 3 days.  Energy levels drop to near zero; sleep becomes
almost constant.  Death follows within a few days.  A ferret can literally
go from perfectly healthy to death in less than a week, solely due to
depression.
[Posted in FML issue 3694]