Artificial Insemination (AI) involves the introduction of sperm into the reproductive tract of the mare without natural mating. AI in the horse was first practiced long ago. Ancient Arabian texts describe how mares were successfully inseminated. In the late 18th Century, an Italian scientist took the idea up again. He performed a series of studies in which he placed stallion semen in the snow and found that he did not necessarily kill the spermatozoa (or “spermatic vermiculi” as he termed them), but merely made them inactive. Upon warming, their motility returned. The use of AI on a regular basis in horse breeding dates back to the beginning of the 20th Century.

The first organized AI programs were run on Russian stud farms. During the past two decades, AI has been accepted by many national and international breed authorities throughout Europe and America. In some countries, for example The Netherlands, several thousand mares are inseminated each year.

There are some breed restrictions to the use of AI, most noticeably the General Stud Book and The Jockey Club, which regulate the Thoroughbred. It is therefore important to know which breed registries permit AI and which do not.

For those of us currently involved in the equine breeding industry, it is obvious that AI is set to play an ever-increasing role in the future. It is equally apparent that there is a need for breeders and veterinarians alike to understand fully and to be familiar with the techniques of AI in the horse. This should ensure first of all the welfare of the horse and secondly the success of AI in the horse.

A successful AI program depends upon both the stallion and the mare, and it involves for the stallion the following compoenents: a thorough examination for breeding soundness, confirmation that the stallion has semen of sufficient quality, and appropriate cooling and storage of the semen sample after collection. <