Be careful,
rabbit
pseudotuberculosis is transferable to humans
Michel Gruaz
(Article published in the animal
journal Tierwelt and graciously allowed to share
here in MediRabbit.com by M. Gruaz)
|
MediRabbit.com is funded solely by the
generosity of donors.
Every donation, no matter what
the size, is appreciated and will aid in the continuing research of medical care
and health of rabbits.
Thank you
|
Warning: this page
contains pictures that may be distressing for some persons.
This sole and
unique reason justifies that owners of rabbits should be informed about this
disease, rare disease, yeti t is observed from time to time. It is important
to recognize it as it is rather atypical.
For several years,
I had 3 cases within few months’ of time, the author of this article can thus
report about the clinical signs of the disease. It affects mostly adult
animals, or those that are several years old. The rabbit eats less and less
and, after a few days, eats only small amounts of fresh food, then stops
eating. The droppings become increasingly smaller, as well as hard and
sticky. The ventral abdomen is soft and during palpation, it is possible to
feel that the content of the abdominal cavity decreases.
The animal loses
weight rapidly. Death follows after a few days, unless the decision was taken
to pts the animal. After presenting the pictures taken during necropsy
to one veterinarian, and later to Dr. med. vet. Richard K. Hoop of the
Institute of veterinary Bacteriology of the University of Zurich (Switzerland),
the diagnosis was pseudotuberculosis. These persons warned the author about
the risks of transference to man and to avoid bringing hands to the mouth
after handling a sick rabbit. It should be noted that no further case has
appeared among the rabbits of the writer.
According
to Boucher et Nouaille the disease is rare in rabbits
Yersiniosis or pseudotuberculosis is rare in rabbit husbandry. It
does, however, affect birds often, e.g. the common wood pigeon or rodents,
including the guinea pig. When there is contact between these and rabbits,
the latter can become infected. The disease is observed in farm rabbits
living in hutches as well as in pet rabbits that live in the vicinity of
birds infected by the bacterium. Wild rabbits and hares can also be a source
of infection. Hares are very sensitive to yersiniosis. In this species the
disease is frequently observed. It is the main cause of mortality in some
regions of France and Germany. The disease is considered zoonotic, that is,
it can be transferred to humans. It affects mainly boys aged 8 to 13. Signs
are similar to those of appendicitis. They can be accompanied by skin
inflammation and redness. Human beings and animals can be affected either by
a generalized infection and severe septicemia, or by localized infections in
the lungs or eyes. The septicemic form leads to death within 24 to 48 hours
while the chronic form may become fatal after 2 or 3 months, although many
survive.
A bacterium called Yersinia is
causing the disease
This infection is caused by Yersinia pseudotuberculosis, a
bacterium that was discovered in 1883 on a guinea pig inoculated with the
nodule of a child that died of tuberculous meningitis. It is a small
cosmopolitan Gram negative bacterium (rod shaped bacterium). This bacillus or
bacterium is present in infected or healthy animal or human beings. Birds and
rodents are the main reservoir. This bacterium can, however, also be found in
the soil, in water or in food soiled with excrements of infected animals. In
rabbits, the bacterium has been observed in fecals as well as in cecal
droppings. It can survive over a year in the soil. It can even multiply at
temperatures between 4 to 10°C. This ability may be linked to the rise of
infected rabbits during the winter season. The ground is apparently is major
source of contamination. Particular care should thus be given when burying a
dead rabbit. Care should be taken when adding manure to the soil. Decay of
bodies in a pile of manure should be avoided. The bacterium can get back to
the soil this way.
After ingestion, the bacterium reaches the intestine where it will
multiply. At 37°C, the bacterial population will grow rapidly and bacteria will
start to invade lymphatic nodules associated to this organ. In the septicemic
form of the disease, the rabbit will die rapidly, without noticeable clinical
signs. In the non-septicemic forms, the rabbit appears tired, emaciated and
exhausted. He stops eating and may suffer from diarrhea. During palpation,
the nodules are hypertrophied. The liver has fairly hard nodules. The
intestine can present necrotic regions. Kidneys and lungs are sometimes
affected. Not all animals die.
Suspicion, onset and passing over of
the disease
Necropsy can be indicative. Hypertrophy of the lymphatic nodules is
observed and the spleen is twice to three times larger than normal. Kidneys,
spleen and intestine have small white/yellowish nodules on their surface.
These nodules resemble those observed with tuberculosis, hence the name
pseudotuberculosis. A bacteriological examination of the affected organs
(kidney, spleen, liver, intestine, bone marrow) is the sole diagnostic tool
that enables to enables to obtain a conclusive diagnosis of the disease. It
is necessary to teach basic hygiene measures to rabbit owners that possess
birds, hamsters, guinea pigs or poultry living in the same barn than rabbits.
The feeding of grains left over by birds living in hutches to poultry is a classical
source of contamination of Yersinia bacteria in the barnyard. It is
also important to look for possible contamination of the soil and plants.
Contamination is often oral and digestive.
The incubation period is long and lasts an average of 15 days. The
bacteria then reach the lymphatic system and nodules appear on different
organs. After the ganglionic stage, the liver is invaded and becomes the
starting point for septicemia.
Prevention is always more desirable
than treatment
It is recommended to disinfect hutches, pens or the living environment
of the rabbit and the soil. Walls can be washed clean. The water should be
treated with an antibacterial product to kill the bacterium, before it is
discarded. Accessories or hay should be burned. Those objects that can be
soaked should be so during at least an hour in a bactericidal solution that
can be found in drugstores. A drinking water chlorine-based disinfectant is
added to the drinking water of the rabbits. Simultaneously riddance of rats
is needed. Other breeding places should also be carefully inspected.
Prophylactic measures should be taken. The treatment itself includes the
administration of enrofloxacin (Baytril), 15 mg/kilo fresh weight during 8
days. After stopping the treatment during 10 days, a second antibiotic cure
is given during an additional 8 days. A bacteriological study (antibiogram)
allows determining the sensitivity of the bacterium to several antibiotics
and can help find the efficiency of another molecule.
More Information
Maladies des lapins de Boucher et Nouaille
Textbook of Rabbit
Medicine, Frances Harcourt-Brown, Oxford,
The Biology of the
Laboratory Rabbit, Patrick J. Manning, Daniel H. Ringler
and Christian E. Newcomer,
Vetstream,
http://www.vetstream.com/lapis/Content/Freeform/fre00324.asp
Zoonoses and Communicable
Diseases Common to Man and Animals: Bacterioses and
Mycoses v. 1 - PAHO Scientific Publications S. No. 580, Pedro N. Acha, Boris Szyfres.
|
|||||||||
e-mail: info@medirabbit.com
