The more important aspect of natural lighting is enough true full
darkness rather than a lot of light.  Ferrets are descended from
animals which lived largely in appropriated burrows and were active
mostly at dawn and dusk, not creatures which scampered around in the
sun.  The reason that darkness is so useful is because it is during
darkness that bodies produce their own melatonin.
 
Re: Ferret Tears; Do they cry?  No, not with tears though they will
whimper or cry with a "whraak whraak" noise, and they can get very
depressed.  If there is a lot of fluid coming from the eyes during a
hard time like mourning than more likely that they have caught a bug
like influenza or a bacterial sinus infection (not a cold) while they
are so stressed and their eyes are watering too much from that.  Stress
does tend to make individuals more vulnerable to infection.  Their eyes
are of course lubricated and that lubrication can increase with
irritation.
 
Actually, MF does not kill the unwanted ones last time I discussed this
topic with an executive there.  I was a little involved with several
industrious and loving people (both out of MF and in it) in setting up
viable alternatives which were welcomed years back and as far as i know
have been used since, and don't forget that MF workers themselves tend
to have ferrets in their families which actually made the need for
alternatives low.
 
The USDA makes its inspection data public.  I don't know if they still
use the old method (where a request is sent to them and then the data is
released) or if they have switched to fully website access now which was
a possibility that was under debate.  You can learn that with your own
searches or by seeking the past posts in the FML Archives.
 
Given my druthers since "backyard breeders" are so much worse than anyone
else who breeds for causing harm to ferrets I'd like to see stronger laws
which provide serious punishments for people who do terrible things to
animals through such a situation.
 
The best, of course, are private breeders who keep serious health and
longevity records and readily cull lines through sterilization if there
are health problems present -- placing health, longevity, personality
and such long before appearance aspects such a pelage.
 
Farms all fall between the two worst and best.
 
Distributors and pet stores are yet a different difficult topic; there
are good ones but there are also horrid ones.
 
Rumors have a tendency to be worse than reality, and that goes for
the ones about MF as well as those too many have sadly encountered.
[Posted in FML issue 4179]