Strangles is caused by a bacterium with the scientific name of Streptococcus equi subspecies equi. But it is usually referred to as Strep. equi.
Horses of all ages are susceptible to strangles but it occurs most commonly in young horses less than two years of age. Foals under three months are usually resistant due to the protection they get from drinking their dam's colostrum. Although outbreaks can occur any time, they are more common in spring.
A horse infected by this organism does not show any clinical signs of illness for three to fourteen days. The horse can, however, shed the bacteria from its nasal passages four to seven days after infection. Therefore, some infected horses are actually shedding the bacteria into the environment before they show any signs of the disease.
- NZ Equine Research
Horses of all ages are susceptible to strangles but it occurs most commonly in young horses less than two years of age. Foals under three months are usually resistant due to the protection they get from drinking their dam's colostrum. Although outbreaks can occur any time, they are more common in spring.
A horse infected by this organism does not show any clinical signs of illness for three to fourteen days. The horse can, however, shed the bacteria from its nasal passages four to seven days after infection. Therefore, some infected horses are actually shedding the bacteria into the environment before they show any signs of the disease.
- NZ Equine Research