The name "strangles" was coined due to the strangled breathing sounds made by horses with enlarged lymph glands that are characteristic of the disease. Strangles is caused by the bacterium Streptococcus equi that is specific to horses and is considered to be the "strep throat" of horses
A sick horse with signs of strangles.
Good horse management techniques are necessary to prevent the spread of strangles through contaminated water buckets, brushes, stalls, fences, and other surfaces in stable and pasture areas.
© 2017 by S. Hanusch New window.
A horse that is exposed to Streptococcus equi will begin to show signs within two to six days and the characteristic abscessed lymph nodes will develop within one to two weeks after exposure. The lymph nodes rupture and drain and the drainage is highly contagious. Typical early signs of the disease include loss of appetite, fever, listlessness, and difficulty breathing.
When the lymph nodes rupture and drain, they often affect the horse's gutteral pouches which contain the nerves responsible for crucial body functions, such as breathing, swallowing, and chewing. When the abscessed lymph nodes drain internally, the guttural pouches and sinuses can become infected. Known as a retropharyngeal abscess, this condition may damage the nerves at the back of pharynx, paralying the swallowing muscles or the muscles of the face and ears.
Prevention of strangles includes separating or quarantining a horse at the earliest signs of the disease. This is important because the disease is highly contagious and may be passed from one horse to another via nasal secretions and pus from ruptured abscesses in the lymph nodes. Horses remain contagious for approximately a month after having the disease.
Good horse management techniques are necessary to prevent the spread of the disease through contaminated water buckets, brushes, stalls, fences, or any other surface in the stable or pasture area. Bleach or other disinfectant should be used to wash down stalls including walls and floors, all equipment and tack, and any other surfaces that may have become contaminated by a horse with the disease. Fortunately, the bacteria die fairly quickly in the environment.
Treatment of strangles depends on the general health of the horse and the severity and stage of the particular horse's case. Penicillin has been effective, but should be administered during the initial stages of the disease or after any abscesses have ruptured. Once abscesses form, penicillin has been reported to delay the opening and draining of the abscesses, which can lead to complications.
In mild cases, some veterinarians prefer to let the disease work its course because the disease is self-limiting and can be fought off by the immune system of most healthy horses without medication. Some veterinarians maintain that antibiotics may do more harm than good by killing off beneficial bacteria the horse needs to fight the strangles infection.