Reproductive Diseases

Horse reproductive diseases can affect horse health in more ways than just their ability to reproduce effectively. Some reproductive diseases can cripple, lead to other more serious afflictions and even kill. A basic knowledge of some of the most common horse reproductive diseases is a good way to start protecting your horse.

Complications Following Castration

Castration is a common practice in the care of a horse”s health and a preventive measure in the overall health of a horse”s reproductive system. It is a necessary operation that can lead to complications and endanger the health of a horse. Most of the issues are common and if handled immediately will not result in any further complications:

  • Bleeding after castration: Bleeding from the wound in the scrotum and from the little artery in the posterior portion of the spermatic cord always occurs. It scarcely ever lasts more than about 15 minutes.
  • Pain after castration: Some horses are pained and very restless for several hours after castration.
  • Swelling of the sheath, penis and abdomen: This occurs in certain unhealthy states of the system, in unhealthful seasons, as the result of operating without cleansing the sheath and penis.
  • Tumors on the spermatic cord: These are due to rough handling or dragging upon the cord in castration, to strangulation of unduly long cords in the external wound, to adhesion of the end of the cord to the skin, to inflammation of the cord succeeding exposure to cold or wet or to the presence of infection.

Some Common Horse Reproductive Diseases

Here is a list of some of the more common horse reproductive diseases:

  • Congestion and Inflammation of the Testicles: In the prime of life, in vigorous health and on stimulating feed, stallions are subject to congestion of the testicles, which become swollen, hot and tender, but without any active inflammation. This congestion can result in actual inflammation when there has been frequent copulation, heavy grain feeding, warm weather and the animal has had little exercise. Blows and penetrating wounds impacting the testicles can lead to further deterioration of the horse reproductive system.
  • Sarcocele: This reproductive disease produces an enlarged condition of the testicles, resulting from chronic inflammation, though it is often associated with a specific deposit. The spermatic cord often increases at the same time with the testicle, and the inguinal ring being thereby stretched and enlarged, a portion of intestine may escape into the sac, complicating the disease with hernia. The only rational and effective treatment is castration and even this may not succeed.
  • Degeneration of the Testicles: The testicles may become the seat of fibrous, calcareous, fatty, cartilaginous or cystic degeneration, for all which the appropriate treatment is castration. The health of a horse is in jeopardy if the testicles become the seat of cancer, or tuberculosis. Castration is the only way to help with this reproductive disease, though it does not always succeed.
  • Warts on the Penis: These are best removed by twisting them off, using the thumb and forefinger. They may also be cut off with scissors and the roots cauterized with nitrate of silver.
  • Paralysis of the Penis: This results from blows and other injuries and also in some cases from too frequent and exhausting service. The penis hangs from the sheath, flaccid, pendulous and often cold. The passage of urine occurs with lessened force and the reproductive health of the horse is, at least in the short term, is squashed.
  • Sterility: Sterility may be in the male or in the female. In the stallion sterility may be due to the following causes:

    • Fatty degeneration of the testicles
    • Imperfect development of the testicles
    • Inflammation of the testicles

    Tumors affecting the testicles or penis in the mare barrenness is equally due to a variety of causes:

    • Cystic or other tumors of the ovary
    • Fatty degeneration of the excretory tubes of the ovaries (Fallopian tubes)
    • Fatty degeneration of the ovary in very obese, pampered mares
    • Imperfect development of the ovary
    • Poor feeding, overwork and chronic debilitating diseases.
  • Tumors of the Udder: A reproductive disease stemming from inflammation of the udder, it may become the seat of a hardened diseased growth, which may go on growing and seriously interfere with the movement of the hind limbs. If such swellings do not give way in their early stages to treatment by iodine, the only resort is to cut them out with a knife. As the gland is often implicated and has to be removed, such mares can not in the future suckle their colts and therefore should not be bred.


Michener, CH. B, V.S. (2007). Diseases of the Digestive Organs. Retrieved March 8, 2008, from the Project Gutenberg Web site: