Several bacteria of the salmonella species are capable of producing acute
infectious diarrhea in dogs. Salmonella remain alive for many months or years
in soil and manure. In dogs, the disease is acquired by consuming raw or
commercially contaminated foods, by eating animal manure, or by making oral
contact with surfaces that have been contaminated by the diarrhea of an
infected dog. This bacterial infection is a risk in dogs fed a raw diet, unless
excellent food-handling hygiene is practiced at all times.
Puppies and young adults are most susceptible, as are dogs whose natural
resistance has been compromised by a viral infection, malnutrition, parasites, or being housed in crowded, unsanitary
Inflammatory bowel disease (IBD) occurs when a dog’s stomach and/or intestine becomes home to an unusually high number of inflammatory cells. These cells cause changes in the lining of the digestive tract, which inhibit the normal absorption and passage of food.
It is important to note that although some of the symptoms may be similar, IBD is not the same as irritable bowel syndrome, which is caused by psychological stress rather than a physiological abnormality.
Signs of illness include fever, vomiting, and diarrhea. The stool may be bloody and
foul smelling. Dehydration develops when vomiting and diarrhea are
prolonged. Bacteria in the bloodstream can cause abscesses in the liver,
kidneys, uterus, and lungs. The acute illness, which lasts four to ten days,
may be followed by a chronic diarrhea that persists for more than a month. Dogs
with chronic diarrhea shed salmonella in their feces and are a potential source
of infection to other animals and humans.
Treatment: Mild cases respond well to fluid replacement. Many salmonella
species are resistant to common antibiotics. In fact, antibiotics can favor the growth
of resistant bacteria and prolong fecal shedding of bacteria. Accordingly, antibiotics are used
only for seriously ill dogs. Sulfa drugs and the quinolones are the antibiotics
Public health considerations: Salmonellosis is a zoonotic disease, so care
must be taken to practice excellent hygiene when dealing with a dog with
salmonellosis. It is important to wear gloves when cleaning up feces and to
disinfect areas where an affected dog has eliminated.
Bordetella bronchiseptica bacteria are frequently found in dogs with the kennel cough complex and other
respiratory diseases. Signs of upper respiratory illness caused by bordetella
include a dry, hacking cough accompanied by a clear nasal or eye
discharge. In puppies and immune-compromised adult animals, secondary
bacterial invasion of the lower respiratory tract following viral illness may
cause life-threatening pneumonia. Dogs who are carrying the organism and may
not even be ill themselves, may still cough or exhale the organism into the
air. Healthy dogs can then be infected by breathing in that contaminated
The bacteria can be cultured from nasal swabs or transtracheal washings.
Treatment: Treat all upper respiratory infections by placing the animal in a
warm, draft-free environment, humidifying the atmosphere, and avoiding
stressful activities that can interfere with a smooth recovery. Antibiotics are
indicated if the dog develops fever and a mucopurulent nasal discharge. Antibiotics
are also indicated for all cases of upper respiratory infection in which
bordetella is isolated. Antibiotics given by nebulizer may be more effective
than those given orally or by injection. This is because the bacteria attach to
the mucosal surface of the respiratory tract and are difficult to reach with
Prevention: Bordetella vaccinations are not routine, but may be advisable for
show dogs, boarded dogs, dogs who go to grooming salons or obedience classes, and dogs who live