Artificial Insemination Techniques With Horses

Artificial insemination is an expensive option that possesses distinct advantages over natural breeding, the chief reward being access to the best stallion irrespective of location. There are, of course, disadvantages to artificial insemination and not all breeds recognize it as a reproductive option. The Jockey Club, Breed Registry for Thoroughbred horses in the United States, Canada and Puerto Rico has set rules in place to prevent registration of horses born out of artificial insemination.

  1. Artificial Insemination

    • Artificial insemination (AI) carries many advantages over live cover, where horses physically meet and breed. AI is a cleaner, safer breeding method, especially from the stallion owner’s perspective. Regardless of the stallion’s temperament, live cover requires additional handlers to control the breeding environment, keeping stallion and mare safe. AI poses no danger to the mare or stallion and one person can collect semen without assistance. After collection, breeders may evaluate semen prior to use or shipment as a means of quality control. Breeders have the ability to split a single collection into multiple shipments, saving a stallion’s energy.

      Artificial vaginas (AV) used in artificial insemination consist of a water jacket covered with a hard shell and rubber liner. A second disposable rubber liner inside the AV collects the semen. A stallion ejaculates based on the temperature and pressure exerted by the AV. The water inside the water jacket should contain water heated to approximately 55 degrees Fahrenheit. Any temperature higher than that can cause pain in the penis and may pose a death threat to the sperm.

      Mares receive insemination preparation in a clean, well-lit environment, including restraint stocks. Passage through the cervix is complicated; therefore the mare should be rectally palpated prior to, and during, insemination.

    Deep Uterine Insemination

    • Artificial insemination plays an ever-increasing role in breed futures. Deep uterine insemination (DUI) utilizes frozen semen; however, breeders commonly use freshly collected semen specimens. Breeders inseminate mares using a minimum of 500 million progressively motile live sperm, known as the insemination dose. Semen enters the mare’s uterus via a slowly advancing a loaded catheter. Once inside the uterus, the sperm travel to the oviduct entrance. It is here that sperm fuse with and fertilize the oocyte (egg).

    Endoscopic Insemination

    • An alternate insemination employs use of an endoscope, which is a long and flexible tube equipped with a bright light source on one end. The endoscope enters the uterus through the vagina and cervix, allowing the breeder to see the tip of the uterine horn. Air passes through the endoscope into the uterus, allowing a visual path inside the mare’s reproductive tract. The semen reaches the oocyte via a specialized catheter gently inserted down the endoscope and is blown out of the catheter.