Strangles, or Streptococcus equi (S. equi), is one infectious disease that can cause a major disruption in performance barns. The swelling of the lymph nodes around the throat can make it difficult for a horse to breathe normally and recovery can take quite some time for a single horse or an entire training barn. However, it is a disease that can be preventable with extra caution. “The number of animals affected by this disease can be mitigated by making biosecurity a priority and recognizing signs of illness,” says Jennifer Strasser, DVM, field veterinarian for the Indiana State Board of Animal Health.
Strangles gets its common name because of how it can affect the horse’s respiratory tract. Lymph nodes become infected, causing swelling and abscesses. The abscesses eventually rupture, and the swollen lymph nodes can compress the respiratory tract. There’s nothing pretty about strangles.
Know the Signs
Strangles is more commonly identified in horses ranging in ages from 6 to 10 years of age, and the severity of the disease can vary. The incubation period for strangles is three to eight days. Younger horses may have more severe clinical signs than older horses, but it affects them all the same.
The most common clinical signs of strangles include:
• Mild lethargy or depression
• Fever of 102⁰F to 103⁰F
• Watery discharge from the nose
If the disease progresses, symptoms can increase in severity:
• Thick, yellow nasal discharge
• Trouble swallowing
• Loss of appetite
• Enlarged lymph nodes in the lower jaw
First Step: Quarantine