FROLICKING FERRETS ALL YEAR LONG
Ferrets' bodies change with the alternating seasons, and it may be
important to provide natural lighting cycles to keep them healthy.
Agustus wearily raises his furry, snow-white head and peeks from his cozy
sack on the third floor of the cage. He fixes his beady, pink eyes on me in
an angry stare. One by one, three more ferrets' heads pop up: Cleo from the
second floor, Brutus from the fourth-floor hammock, and Ambro out from under
Brutus. I can just hear their collective, unspoken thought. "I hate it
when you do that!"
I can't blame them. It is one of my own pet peeves to have a light turned
on overhead while I am sleeping. Yet, nearly every evening for the last
three years, I have trooped into the computer room where my ferrets live and
flicked on the lamps: one in the corner and one over the monitor and
keyboard. Ah! Brightness, just as darkness falls outside. And I wake up the
ferrets. I have discovered that this might not be a good idea.
While our human days are not confined to the natural hours of sunshine
anymore, some of the changes in our ferrets' bodies are dictated by
fluctuating hours of daylight. Although these changes are natural and do not
present immediate concerns for health, some ferret experts and enthusiasts
say the long term health of a ferret may depend on the animal's exposure to
a natural pattern of lighting, which could decrease the prevalence and
relieve the symptoms of adrenal gland disease.
When the temperature cools and days grow shorter, our fuzzies gain
weight. At the same time, thick winter fur grows on their bodies, making
many ferrets look lighter in color. In spring these changes reverse.
"A ferret's big seasonal change is the loss or gain of about 30
percent body weight," says veterinarian Mark Burgess, who has been
working with ferrets for more than 10 years.
This sounds like a lot, and it is. Imagine a 150 pound person losing
fifty pounds every spring and gaining it back in the fall. This sort of
fluctuation in a ferret's weight will be obvious to the pet owner, but all
ferrets do not gain and lose so much, and more subtle changes may go
unnoticed. Veterinarian Arlene Jones, of Portland, Oregon, explains
that the seasonal change in weight, however small or large, is a result of
fluctuating hormones that regulate a ferret's metabolism. In the fall,
ferrets retain fat due to a slowed metabolism. Our fuzzy friends then lose
weight in the spring as the days lengthen and the metabolism speeds up. The
hormonal changes are triggered by day length.
Veterinarian Tye Wood, also of Oregon, says there is "quite a
variation" in what may be considered a healthy weight for a domestic
ferret. He has seen healthy ferrets in his practice weighing less than one
pound, and others that tipped the scales at nearly seven pounds -- about the
weight of a newborn human baby.
My own female ferret, Ambro, won the prestigious title of "heaviest
female" at the Oregon Ferret Association's 1996 fun match, weighing in
at about two pounds. A larger female grabbed the blue ribbon the following
year, however, when Ambro, still healthy, had simply slimmed too much to be
competitive. Usually, as with Ambro, seasonal weight change is not a major
medical problem, says Wood, and it takes care of itself.
Another common seasonal change in pet ferrets is modification of the
coat. According to Dr. James Fox, author of "Biology and Diseases of
the Ferret," a winter coat change usually happens in November, at the
same time extra weight comes on. Shedding occurs in late spring or early
summer.
In the summer, according to Fox, "the coat appears sleeker and lies
flatter," while the winter coat is fluffier and softer because a thick
undercoat covers the body. The undercoat is light colored, which explains
why many ferrets look much darker in the summer and have a more clearly
pronounced mask on the face. Ambro, for example, wears a raccoon-like mask
in the summer, which almost completely gives way to white fur in the winter.
Brutus' rich Siamese color, on the other hand, becomes much lighter all over
his body in the winter, and he becomes much softer to the touch.
These coat changes, like weight change, happen because of the fluctuation
in day length, which triggers hormones, including estrogen, that regulate
the growth or loss of hair, Fox says.
Burgess says neutering and "captive conditions" may result in
less consistent coat changes. For example, leaving lights on at night will
lengthen the ferret's day and can cause the animal to keep the same coat for
more than one season. He says that this is not a medical problem, but some
ferret fanciers and experts suggest that manipulating a ferret's exposure to
light may be an important aspect of the animal's long-term health.
Mike Janke, ferret owner and secretary of the South Florida Ferret Club and
Rescue, has been gathering information on the topic for more than a year.
His article in the newsletter "Ferret Footnotes" explains that the
light cycle to which a ferret is exposed directs seasonal changes by
stimulating glands, including the adrenal gland, which produces hormones. If
the gland is over-stimulated and begins to function abnormally, then the
ferret develops adrenal gland disease, common in ferrets four years old or
older.
Symptoms are grossly exaggerated seasonal changes, such as extreme hair
loss. For example, Janke says one afflicted ferret at the South Florida
shelter, Flower, was left only with "a few tufts of hair on her head
and on her legs," being otherwise completely naked.
The possible root of this problem is simple, Wood says. "The
biological clock of Earth is the sun, but people don't live by the sun
anymore."
Ferrets live by whatever schedule their owners adopt. This can include
many consecutive hours of exposure to light that would not normally occur. I
do this myself when I work at the computer in the evenings and light a room
that would otherwise be dark. If such unnatural cycles of light contribute
to the prevalence of adrenal gland disease, some say, then a natural pattern
of lighting may prevent the disease and help to relieve its symptoms.
Still, these assertions remain speculation. Veterinary researchers have
studied the question, but many maintain that investigators have not
uncovered a conclusive answer.
"No one is quite sure of the role light plays in ferret
health," says Maryland veterinarian Karen Purcell, who owns four
ferrets herself. Janke concedes that it's a pretty sure bet that light
regulation is not a cure for adrenal disease, but he maintains that it may
be a preventative measure, and it cannot possibly be harmful.
Dayna Frazier of Virginia, a ferret shelter operator for more than
eighteen years, agrees. "Ferrets require natural sunlight to be healthy
and happy," she says.
Both of these ferret owners, and some veterinarians, recommend that pet
owners regulate ferret's light cycles. But how?
Frazier's method is neither complex nor expensive. She recommends that
ferret owners install four-foot, full spectrum lights over their ferret
cages or in ferret rooms, above human head height, and connect them to an
appliance timer to regulate the hours of light for their pets. The
approximate cost of two bulbs, a fixture and timer is $30.00.
Wood agrees that full-spectrum lighting will best emulate natural light.
"It's hard to beat Mr. Sun," he says.
Wood suggests setting the timer for the lights to come on at sunrise and
go off at sunset. A newspaper or tidal guide will give the times to set the
lights. Check these sources weekly to adjust the timer, says Wood. Depending
on geographical location, this method will result in about 10 total hours of
light per day in the winter, changing gradually to 14 in the summer.
Burgess recommends the same total number of lighted hours, but he says
the use of full-spectrum lighting "is not critical." Regular
incandescent lights will work OK, he says. A good rule of thumb for
determining brightness, says Frazier, is to make sure the bulbs provide
sufficient light to grow healthy African Violets.
One problem with this schedule is that many pet owners like to spend time
with their ferrets during a period of the day that is normally dark. A
possible solution is to use red lights to simulate nighttime, says Christine
Mathis, owner and operator of the Oregon Ferret Shelter. The idea is to
provide light for the humans that will not interfere with the ferrets'
natural light cycle. Mathis says the idea was suggested by a consulting
veterinarian for the shelter.
Yet, no one knows if red light is really harmless, says Wood, in terms of
affecting a ferret's normal light cycle.
Frazier is certain her technique is successful. Even ferrets with
advanced cases of adrenal disease experience reversal of symptoms when
introduced to her shelter's lighting program, she says. Without it, they
live shorter lives. Ferrets bodies do change with the seasons, and in some
cases quite drastically. Helping our pets by accommodating natural seasonal
change, and encouraging healthy cycles that may keep the adrenal gland in
check, could result in happier, longer relationships.
According to Fox, the life span of a pet ferret is between eight and
eleven years. My own Agustus will be three next year, and Ambro will soon
turn four. Brutus and Cleo are about two years old. None of them has yet
shown symptoms of adrenal gland disease, and I'm keeping my fingers crossed
as they grow older. Yet, I'm not going to rely entirely on crossed fingers.
When Ambro turns four this spring, I will give them all red lights for her
birthday.
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