Actually it may be the other way around.  Darkness may be more important
than sunlight exposure.  The photoperiod is what starts the ferret breeding
season in the early spring and what terminates it in the early fall.  It is
actually the amount of darkness that controls this.
 
The amount of darkness controls the amount of melatonin
that is produced. During the short days of the fall/ winter
(i.e., more darkness) more melatonin is produced. Melatonin
directly and indirectly acts as a GnRH inhibitor. During the
long days of the spring/summer (less darkness) less melatonin
is produced. GnRH is released and the breeding season happens.
In ferrets that have been spayed or neutered, the adrenal glands
act like gonads. The adrenal glands have LH receptors and respond
to stimulation (long light days) by producing the sex hormones.
Most ferrets that are kept indoors are exposed to long days year round.
This overstimulation may cause adrenal hyperplasia and tumor formation
(adrenal gland disease). This is also why melatonin and Lupron depot can
be used to medically treat adrenal gland disease. Thus it is important
to make sure your ferret gets enough darkness to help prevent adrenal
gland disease. At 12 weeks of age, she should be old enough and her
teeth big enough to eat Totally Ferret without adding water to it.
Remember she is in a rapid growth stage, so she will indeed need all
the food she can eat. Only time will tell if angoras are less likely to
get adrenal gland disease and insulinomas, but I do not expect that to be
the case.
 
Hope that helps,
Jerry Murray, DVM
Dallas, Texas
[Posted in FML issue 3491]