It is thus an equine venereal disease of the genital tract of horses, brought on by the Taylorella equigenitalis bacteria and spread through sexual contact.
[1] Signs in mares appear ten to fourteen days after breeding to an infected or carrier stallion.
In stallions, samples are taken from the skin folds of the prepuce, urethral fossa, urethra, and the pre-ejaculatory fluid.
Taylorella equigenitalis is susceptible to most antibiotics, although the carrier state in mares is difficult to eliminate.
The disease was first reported in 1977 on horse breeding farms in England, when an unusually high proportion of mares were not becoming pregnant.
[3] A second American outbreak occurred a year later in Missouri but in both cases, the diseases were quickly eradicated.