Horse breeding is part science, part art, part craftsmanship. We choose our mare and stallion carefully, hoping that together they will pass on their finest traits to the foal. But despite all our detailed planning, the end result may still be somewhat of a surprise. Perhaps we get a solid color when we’d hoped for a splashed paint or a little guy when we’d expected a hefty type. Experienced breeders know that surprises are a part of the business, but they also know that there are many steps they can take to make the process go smoother. This month’s “Horseman’s Corner” brings you tools of the breeder’s trade.

Good Hygiene
One of the most important tools of the trade is good hygiene. Disposable gloves, disinfecting all instruments, and frequent hand washing prevent diseases like EVA (Equine Viral Arteritis) and CEM (Contagious Equine Metritis). CEM is a sexually transmitted disease and can be passed during artificial insemination as well as live cover. Technicians, veterinarians, and all handlers must use disposable gloves and change them between each horse. Using disposable items when available and thoroughly disinfecting all non-disposable items, including collection units, surgical instruments, and phantoms goes a long way in preventing disease outbreaks.
When breeding a mare, ask the owner if his stallion has been tested and cleared for CEM. If the stallion is a new import to the United States you should be able to obtain a record of his disease status. If the stallion also does live cover, the risk is higher for contracting and transmitting CEM, EVA, and other bacterium, but this should not exclude him as your choice so long as the farm has solid hygiene practices in place.

Tools for Testing Semen
Hemocytometer: After collecting the semen from the artificial vagina, large breeding facilities will test the semen for motility and concentration. The hemocytometer was originally developed to count blood cells, but is now also used for different types of cells and microscopic particles. Through intense magnification, the technician is able to count the number of sperm within a pre-described grid. The information gleaned from the hemocytometer will help determine how much to dilute the semen prior to shipping.
NucleoCounter-SP-100: At a cost of somewhere around $15,000 as opposed to the hemocytometer at $200-300, it is out of reach for many small breeding operations and labs, but its accuracy and ease of use surpasses the hemocytometer by a long shot. The total cell count can be had in 30 seconds.
PH Testing: We know that normally semen is alkaline. This alkalinity offers built in protection against the acidity of the vaginal fluid. Semen that tests acidic can indicate a problem with stallion fertility.

Collecting
Breeding Phantom: Most stallions can be easily trained to mount a breeding phantom. The phantom is designed to mimic the body of a mare and should be angled to encourage the stallion to mount correctly. The phantom is soft and padded to protect the stallion from injury.
Artificial Vagina (AV): The artificial vagina is used to collect semen from the stallion for use in artificial insemination programs. The artificial vagina is placed into the phantom mare. As the stallion ejaculates, experienced handlers lower the AV to allow the semen to run into the collection bottle. Once the stallion ejaculates, the AV is removed and incubated.
Shipping Containers: These vary in style, but are usually made of a molded plastic exterior. The Equitainer® has built in x-ray protection, a double centrifuge for easy handling, and recessed latches and hinges to protect accidental opening during shipping. Containers are on loan for the duration of shipping and must be returned to the breeding facility.

Insemination
Artificial Insemination (AI): This process is a relatively simple procedure that can be performed by your equine veterinarian. The mare is restrained in breeding stocks during the procedure to protect handlers. Her perianal area is thoroughly scrubbed with a Betadine® solution or similar surgical scrub, and her tail should be wrapped and secured to the side. Your veterinarian will remove the semen with the use of a pipette. The pipette is gently moved through the center of the cervix and into the uterus where the semen is deposited.
Endoscopic Artificial Insemination or Deep Horn Insemination: This process is sometimes performed when there is a question of fertility, a lower sperm count, or in the case of extremely valuable (but low quantity) sperm. Through the use of an endoscope, a veterinarian deposits sperm at the uterotubal junction of the pre-ovulatory mare. The procedure is rather expensive and requires specially trained personnel, but has a high success rate.

Fetal Monitoring
EKG: Your veterinarian can perform a routine EKG in the field. The electrocardiogram offers valuable information on the health of the fetus by measuring the heart rate. Using a 24-hour fetal heart rate monitor helps to track the heart rate during the mare’s average daily activity. The information used is valuable in detecting problems.
Ultrasound: Like the EKG, the ultrasound is a non-invasive method of making sure the fetus is healthy and can also be performed in the field. It provides information on position, movement, size, heart rate, and placental thickness and integrity. The drawback of the ultrasound when used in equine reproduction is its inability to provide a view of the entire foal at once. Because of the size of the foal in late gestation, the ultrasound provides its total picture in bits and pieces. The veterinarian must put the pieces of the puzzle back together in order to create a complete diagnostic picture.
Blood Tests: A simple blood test can also test your mare’s progress. Blood is tested for hormone levels. If abnormal levels of progesterone or estrogen are found, your veterinarian may prescribe special treatment.
The goal of every breeder is a healthy foal. We may not have ultimate control over the color of the little guy, (or girl), but we do have some control over the process of breeding, gestation, and foaling. Establish a good relationship with a qualified equine veterinarian and consult on any questions that arise.

Photo by Helen Peppe