Bacterial Infections and Horses

Bacteria is everywhere and while most microorganisms do not have much impact on our daily lives, some types can cause disease. Our horses are exposed to bacteria daily and most of the time their immune system is able to fight it off without showing any signs of sickness. Bacterial disease occurs when a horse’s immune system is weakened and the bacteria is able to replicate and spread in the horse’s body.

Common types of pathogenic bacteria in dogs include:
– Tetanus
– Potomac Horse Fever
– Salmonella
– Strangles
– E Coli

The source of bacteria is usually contaminated water, food or feces. Horses tend to get infected with bacterial diseases after their immune system has already been compromised by a virus. Bacterial infections are more common in horses that that travel or spend a lot of time at training stables where lots of different horses are coming and going. Foals and geriatric horses are much more at risk of becoming sick because their immune systems are not as strong as adult horses in their prime.

Horses who are sick with a bacterial infection usually have digestive upset (diarrhea) or an upper respiratory infection (coughing, runny nose). Bacterial infections typically cause a fever and lethargy. Cleanliness practices around the barn are key to keeping bacteria from spreading. It is a good idea for each horse to have their own supplies and grooming tools to prevent spreading germs in stables where many horses from different owners are living together.

If you think your horse may have a bacterial infection you should call your veterinarian. Vets typically treat bacterial infections with antibiotic drugs and in severe cases additional support such as fluids for dehydrated horses may be needed. Left untreated, bacterial infections can lead to colic or laminitis.


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Evaluation of working conditions of workers engaged in tending horses.

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