Brucellosis
Race Foster, DVM Marty Smith, DVM
Drs. Foster & Smith, Inc.
Brucellosis is a disease
caused by Brucella canis, which is a bacteria that was first isolated
from dead
puppy fetuses in the middle 1960’s. It is the most common bacteria that
can
infect bitches and their fetuses. It seems that over the years much has
been
written on brucellosis in breeding dogs, but despite it all, infection
rates
may run as high as 8-10%. That is right, it is suspected that one in
ten
dogs in this country may carry Brucella canis.
Brucella canis also poses a significant public health hazard since it
is transmissible to humans, especially those handling aborted fetuses.
Humans may develop a serious liver impairment or arthritis.
Medical advancements in controlling this disease have been few and far
between. Contrary to some opinions, it is a very difficult disorder to
treat,
and in most cases, treatment is unsuccessful. A prevalent attitude
among
many people is that "if my dogs get it, then I will treat it." This is
a
serious mistake because you probably will not cure it, and if you do,
the
individual will probably be sterile or be a poor breeding specimen.
Transmission of Brucella canis
B. canis is sexually transmitted by the mating of infected males and
females. Brucella canis in the female dog will live in the vaginal and
uterine tissue and secretions for years, and except in rare cases, for
life. The infected female usually appears healthy with no signs of
disease or indication that she is a 'carrier' or harborer of the
organisms. She can spread the bacteria to other animals through her
urine, aborted fetuses, or most commonly through the act of breeding.
Once pregnant, the bacteria will also infect the developing fetuses
causing illness.
In males, the Brucella bacteria live in the testicles and seminal
fluids. An infected male is just as dangerous as the female as he can
spread the
Brucella bacteria via his urine or semen. Oftentimes, there are no
signs
except in advanced cases when the testicles may be uneven in size.
Litters are commonly aborted, usually in the last two weeks of
gestation, or the puppies may die shortly after birth. If a pregnant
dog aborts after 45 days of gestation, you should be highly suspicious
of brucellosis. Usually, the fetuses are partially decayed and
accompanied by a gray to green vaginal discharge. This discharge can
have very high numbers of Brucella canis.
If embryos die early, they may be reabsorbed and the female may never
appear to be pregnant at all.
What are the risks?
The risks are great. Since the Brucella canis organisms are
transmissible to humans, it is best to avoid all contact with the dead
fetuses and their associated vaginal discharge. The infected mother
will likely be unable
to sustain a pregnancy in the future. Furthermore, she would likely
transmit the disease to any male which breeds her causing fertility
problems in him as well.
Testing
Testing for Brucellosis usually requires a blood test by your
veterinarian and all positives should be retested for a confirmation.
Since Brucella
canis is mainly spread by the act of breeding, it is paramount to test
all
canines, male and female, prior to breeding. Test between every
breeding
of different animals. In other words, if a male (or female) was tested
one
year ago but has bred since, he must be tested again. In the case of a
male,
if he serviced a female since his last test, then he must be tested
again
even if his last test was as recent as four weeks ago. Testing is the
only
sure way to detect carriers.
In cases of abortion, the bacteria may be isolated from the aborted
fetuses. Blood tests can also be performed on the mother's blood to
help confirm
a positive diagnosis of Brucellosis.
Prevention
When possible, all incoming breeding dogs should be isolated for two
weeks upon arrival at the kennel. At the end of two weeks, have the
individual
(male or female) tested by your veterinarian for brucellosis. Do this
even
if the dog was tested before shipment. This may seem excessive, but you
will
spend a lot more money if Brucellosis creeps into your kennel, not to
mention
the disruption in your breeding program and loss of genetic potential.
Artificial Insemination (AI) can lessen the risk of Brucella transfer
at breeding. While rare, transmission of Brucella canis to a bitch can
occur during AI, especially if infected semen is used. However, AI will
protect an infected female from transferring it to a noninfected male.
All positive males and females should not be bred. Surgical spaying or
neutering of these individuals is recommended. Various blood tests are
available
to screen breeding dogs (male and female) and identify those who are
infected (carriers). All individuals used for breeding should be
routinely tested
prior to breeding.
Treatment
There is no reliable treatment for Brucellosis. Brucella canis lives
inside of the dog's cells so it is difficult to reach the bacteria with
antibiotics. Any attempt at treatment would require the use of multiple
types of antibiotics. Various antibiotics such as doxycycline,
minocycline, and dihydrostreptomycin have been partially effective at
causing a temporary reduction in the bacterial organisms after several
weeks of treatment. A complete cure is unlikely.
It is recommended that infected animals be castrated or spayed.
As a rule, do not breed your dog with an individual that is said to be
treated and cured. (Unless of course it is the last of its breed and
even
that would be questionable.) 'Cured' patients often begin shedding the
bacteria
months to years after treatments... Do not knowingly take a chance.
Human health hazards
People can become infected with Brucella canis. People should avoid
contact with dead fetuses or the discharge from aborting dogs.
Transmission has
also occurred from contact with secretions from male dogs.
In conclusion, test and isolate. Do not rely on an uncertain cure. If
you do not heed these suggestions, then you are playing with fire in
your kennel and perhaps with your own health. Remember, statistically
one out of ten
dogs may be carriers and those are very disturbing odds.
Copyright © 1997-2007, Foster & Smith,
Inc.
All Rights Reserved.
Reprinted as a courtesy and with permission from PetEducation.com (
http://www.PetEducation.com)
On-line store at
http://www.DrsFosterSmith.com
Free pet supply catalog: 1-800-323-4208
reprinted with kind permission from Josie Pitterle Article Reprint
Coordinator Drs. Foster and Smith