Ejaculatory disorders of the stallion.

Ejaculatory disorders of the stallion seem to occur more frequently than hitherto accepted. The condition is manifested differently in individual stallions from normal copulation without ejaculation to an abnormal pattern of copulation without or with occasional ejaculation. The condition is probably caused by a functional disturbance of the nervous mechanism which controls the ejaculatory process, and may be caused by environmental or other factors. Eleven cases of ejaculatory disorders in normal healthy stallions were investigated and three of these animals recovered after simple correction of environmental factors, including the number of mares served. Of the eight stallions which did not respond to environmental changes, one recovered after treatment with pilocarpine and one after treatment iwth ephedrine. Possible causes of failure of the nervous regulation of the reproductive tract are discussed.