From:
RRC
Date: 2001-05-31 16:18:00 UTC
Subject: Bob C: Back Online; Fractures in Wild Animals; Vet Costs
I am officially back online, although it will take considerable time to
catch up on the older lists and the ton or so of email. Forgive me if
any of my posts answer questions already answered.
[Private email]: "I was wondering if wild animals had broken bones and
survived? Aren't they killed because of...their injuries? ...How do you
pay [vet costs] for all your ferrets?"
For some reason, this question reminded me of the Far Side comic where
the vet is walking through the horse ward, saying "shoot it" regardless
of what was wrong. Down the line was one horse with wide eyes.
ALL wild animals, including polecats (the ferret progenitor) and feral
ferrets from New Zealand frequently break bones and survive. I have
personally seen hundreds of examples, ranging from a healed white-tailed
deer humerus (broken by a bullet), to healed raccoon baculae, to a
crushed and healed opossum skull, to a crushed cougar pelvis, to even
healed fractures in ferrets. Wild bears have a very high rate of healed
fractures; in some populations it may exceed 50%. I think the healed
fracture rate in Goodall's chimps was around 10%, and the rate was 17%
in a population of pine martens from British Columbia that I had the
pleasure to study. In the New Zealand feral ferrets I've looked at, the
healed fracture rate was about 8%, but that could hardly be taken as
accurate since many of the feral ferrets in that country are hunted,
trapped and poisoned, which probably skews the finding.
I strongly insist that IF you EVER suspect your ferret has a broken
bone, you seek a vet immediately and take their advice to heart. The
survival rate of a wild animal with a broken bone depends on three basic
factors, collateral damage, immobility, and infection, but for pet
ferrets, nearly all broken bones are survivable. If you do not seek
treatment for your ferret, then they becomein essencethe same as a
wild animal, and will have a much lower survival rate compared to
ferrets getting treatment. In terms of collatoral damage, an injury
damaging enough to break a bone often (or usually) results in other
injuries. One thing I noticed when looking at feral ferret skeletons was
that there was a much higher rate of fracture for the femur than the
humerus. However, once you realize that the head is much closer to the
humerus than to the femur, the difference in fracture rates may be
actually illustrating collateral damage; a hit to the shoulder area may
be also causing head injury, lowering survival rates, and artificially
elevating femur fracture rates in comparison. The same danger of
collateral damage exists in the home environment; a ferret falling from
a bookshelf may show a broken femur, BUT it can have internal injuries
to the liver or spleen which would result in death if not treated
promptly. This is really important if the ferret was stepped on, where a
broken limb might be obvious, but the real danger is internal injuries.
If you suspect a broken bone, assume there is collateral damage until
proven otherwise.
Immobility is caused by pain or inability to walk. If the break is
severe enough, since the blood vessels and nerves follow the bone, there
is a good chance that they will be injured by or during the break. This
is especially true if the fractured bone ends are sticking through the
skin. An animal with nerve damage rarely survives in the wild (they do
just fine as pets). I have seen dozens of skeletons of predators where a
fracture was apparent, but it only healed for a couple of weeks, just
long enough for the animal to starve to death (I have never seen a
similar case in prey species because they are generally culled by
predators soon after injury). Predators, such as the ferret, have
evolved the ability to go considerable time without eating (the idea
that a ferret HAS to eat every few hours is a myth; excepting sick
ferrets, most can easily go a day or two without food with NO ill
effect). So even if a break causes short term immobility, there is a
fair chance that as the callus on the bone begins to harden, the animal
can start to hunt and get enough to eat to survive (which must have
happened in each and every case where a wild animal has survived a fracture).
Infection is the real problem, and why *I* think every ferret with a
broken bone needs to see a vet. Bone infections are deadly,
debilitating, painful, and even with modern drugs and knowledge, may not
be totally curable. Because bone is the center for fat storage and blood
cell production, it is very vascular; that is, there are a LOT of blood
and lymph vessels which are perfect highways to carry infection to the
rest of the body. Infected bone dies little by little, weakening and
eroding away, leaving behind horrific gaps and holes and large sections
where the bone is bubbly and weak and just plain nasty. The absolute
best cure is prevention. Do not assume that just because the bone has
not poked through the skin, it will not become infected. I have seen
dozens of examples where a simple, minor fracture has become infected,
leading the the death of the animal. Ferrets with fractured bones need
to see a vet.
Wild animals never get to see vets and they do survive. It takes about a
week for the blood clot around the bone to begin to harden enough to
prevent the bone ends from grating against each other. It still cannot
bear weight, BUT, it allows mobility and a search for food. After two
weeks, the blood clot around the bone has been turned into a spongy,
soft bone-like substance called a callus. In three weeks, it will easily
support the animal's weight, although it is weaker than the surrounding
bone and may still be painful. After about a month, while the bone is
not fully healed and the callus is still rough and spongy, the bone is
well enough to be considered functional. This process occurs regardless
if the bone was splinted or not.
The difference is, splinted bones do not have ends which move against
each other, breaking up the callus or causing additional bleeding (or
tissue damage) which makes the callus larger. Splinted bones are not
very painful; if you have ever suffered from a broken bone, you know
that after the initial pain goes away (2-5 days or so), it doesn't hurt
much. That is NOT true with unsplinted bones, which can hurt for weeks.
Obviously, a broken bone, if not splinted straight, could heal crooked,
but it can also heal without knitting, resulting in a false joint where
the two ends of the bone did not heal together.
Splinting the lower leg bones is simple and effective; you just
immobilize the break as well as the closest top and bottom joints, and
that is all there is to it. Upper limb bones are a different matter.
While humans tolerate body casts to immobilize the shoulder or pelvic
joints, most animals do not, so using a splint is difficult. In those
cases (and even for humans), the best solution is to pin or plate the
bone, which requires surgery. When you pin a bone, you basically drill a
hole and push a rod (or pin) down through the marrow space; this acts
like a dowel to hold the broken ends together. A plate is a small piece
of metal which is directly screwed to both ends of the bone, like a
joiner plate holding two sections of rail together. In ferrets, the
bones are so small (not in size, but in thinness of the compacta which
supports the screws holding the plate), that plates are difficult to
use, and pinning is generally preferred. In some cases, the bone is so
fragmented that neither pinning or plating will work, and sometimes wire
is used to "sew" or "wrap" the larger fragments together. Sometimes
these devices are left in the ferret, but often they are removed later.
The best part about plating or pinning is the ferret can usually use the
limb in a few days.
Sometimes a ferret cannot risk surgery, and the bone cannot be splinted.
The best solution is simply quiet rest. The bone will typically heal
well enough on it's own, believe it or not (that's how wild animals get
by without vets). This happens much more often than you might think;
when a ferret breaks a bone, but it is not always noticed by the owner.
It also happened to my Bear. When Bear was a few months old, he fell on
his hip, pushing the head of his femur through the cup in the pelvis
that holds it (the acetabulum). The tiny bone fragment from the
acetabulum hid the fracture to the head of his femur, which wasn't
noticed until it was mostly healed. Because the treatment was a couple
of weeks of enforced bedrest, the bones healed fine, and while Bear now
has hip problems (he has reinjured the hip twice), they are probably no
more than what would have been expected if surgery was done. It
important to closely monitor the situation, watching for signs of
infection, the bone being moved out of position, or other problems. And
even if this is the course of action you are forced to take, make sure a
vet is involved from the onset. You need an x-ray to make sure the bones
are properly aligned, and vets are trained to look for the slightest
sign of infection and can get immediately involved if the situation
warrants action.
I almost became a vet rather than a zooarchaeologist, but I knew I
couldn't face the frustration of hearing a client tell me they couldn't
afford to treat their pet. People always tend to take in far more
animals than they can afford to care for, and they justify it by saying
the animal is better off. Maybe so; I'm not the judge. From my
experience, ferret owners forget that the cost of a dozen ferrets is NOT
just food and yearly shots, but ALSO a lifetime of medical expenses
compressed into a half dozen years. Ferrets are not sicker than any
other animal; they just have short, compressed lives, which translates
into your pocketbook as yearly medical expenses, especially after the
ferret's 4th birthday (consider if your own life was compressed into an
8 year period; think about how often you would have gone to the doctor
on that timescale and what the annual expenses would be). If you cannot
afford veterinary expenses, then please rethink your desire to own more
than a few ferrets at any given time. I have always suggested to only
own HALF the number of ferrets you think you can afford, because like it
or not, medical expenses will cost you twice what you expect.
I have started a special savings account for my vet expenses. I averaged
my ferret medical costs for a couple of years and deposited that amount
in the account. If you can't afford the total amount, break it up over
several months; I used a tax refund to start the account. If you still
can't afford it after breaking the cost into several months, then you
simply cannot afford the number of ferrets you already own because the
sum represents what you pay out EVERY YEAR in medical costs. I then
divided the average yearly cost by 12 and place that amount in the fund
each month, plus 10% extra. Resist any desire to borrow against the
account. It has saved my butt more than once. For me, with 15 ferrets,
that translates to $75 per month (actually $71.73, but I rounded it up),
which covers my average number of surgeries, shots, and close and
personal inspections. It is a special account using a check that I or
other trusted caregivers can sign. Since I have started the account, I
have never had to hesitate starting treatment because of financial
considerations, and I have the piece of mind knowing that if I am gone
from home, funds are available for the caregivers to begin immediate treatment.
Bob C