Stallions Ready for Action

Before your stallion heads to the shed, make sure he’s in peak physical health and mentally prepared to handle the rigors of the breeding season.

Another breeding season is just over the horizon, and stallion owners and managers will soon be awaiting the arrival of mares for live cover, or orders for shipped semen. Breeding season dates and methods vary among registries, but they have one thing in common: when the season starts, managers must have done their homework so stallions in their charge are healthy, virile, have a high sperm count, and present a strong libido.

Preparing the stallion for breeding season is a year-round job involving proper diet, exercise, and many other factors. It's important to consider stallions with special needs or those breeding for the first time.

Two researchers with extensive experience in the equine reproduction field, Edward L. Squires, MS, PhD, and Juan Samper, DVM, PhD, Dipl. ACT, will provide helpful suggestions for stallion owners and managers preparing for the upcoming season.

Squires is executive director of the University of Kentucky's Gluck Equine Foundation and research professor in UK's Department of Veterinary Science. Samper is a private practitioner in Langley, British Columbia, specializing in reproduc-tion.

Another resource is an article The Horse published by the late John Steiner, DVM, Dipl. ACT, who practiced at Hagyard Equine Medical Institute in Lexington, Ky., prior to joining Rhinebeck Equine in New York as theriogenologist (veterinary reproductive specialist). Steiner was a mentor to many, a wonderful source of information for The Horse, and he is greatly missed.

He outlined a management approach:

"Look at the physical condition of the stallion. Is he overweight or underweight? Is he getting out and getting exercise? It's good for a stallion to get out as much as possible, not only for exercise, but for his overall well-being. Make sure his teeth are okay. He should be on a regular vaccination schedule. All of his vaccinations should be given 30 to 60 days before the breeding season starts. I prefer 60 days. That way, if he has a reaction to the vaccination and gets sick or has a fever, it won't affect his breeding ability. Don't vaccinate the stallion in the middle of the breeding season because a high fever can affect sperm, which take about 60 days to mature in a stallion.

"For any stallion, I recommend a breeding soundness exam prior to the breeding season. This includes collecting the stallion and evaluating the semen. This gives you a baseline to evaluate ... or can help you find problems early and allow you to manage the stallion differently. Then, if there is any problem during the breeding season, you have a baseline to go back to and compare to see where the problem lies."

Determining semen volume and quality is especially important in the young stallion, say Squires and Samper, especially if he is coming off the racetrack. These stallions often have smaller testicles than normal due to stress and, perhaps, some medication types. The testicles return to normal size rather quickly--generally in a month or two--and the young stallion, barring other problems, will be capable of producing adequate healthy sperm.

Breeding Shed Introduction

One of the next steps is to familiarize the stallion with the breeding routine.

It is very important to get a young horse started right in the AI breeding shed. This involves everything from teaching him to drop his penis so it can be washed, to correctly mounting the breeding phantom.

Proper handling of the stallion on a year-round basis is paramount, in Squires' opinion. Quite often, he says, one of the most common causes of infertility in the stallion is mismanagement.

Make sure you consider the horse's age. Squires is a strong proponent of waiting until a stallion is 3 years old before breeding. A 2-year-old stallion might produce adequate sperm amounts, but stallions bred at 2 are more apt to develop bad habits, such as mounting without an erection and excessive biting of the mare, he says.

Overuse, particularly in the young horse, can also lead to development of problems. If a stallion is pushed too hard, Squires says, sexual behavior problems can develop whether using natural cover or collecting. Overuse can occur especially when breeding in the fall or winter months, which is when a stallion's libido is the lowest.

Lack of exercise, housing in isolation, and having been kicked during breeding are all implicated in causing sexual behavior problems, notes Squires. Stallions that have been kicked are often those that mount the mare, enter her, and begin thrusting, but do not ejaculate.

Managers often put mares under lights, beginning in the fall, to bring them into estrus, but Squires doesn't recommend this for stallions. He says it changes the time frame for peak sperm production, and this could cause the stallion to reach his peak too early in the breeding season, when the fewest number of mares are booked.

Posing potential harm to stallions in this regard, he feels, are barns, such as security-monitored show barns, where light is provided 24 hours per day.

An important aspect of a stallion's preparation for AI breeding is mounting the phantom and ejaculating into an artificial va-gina. It is a case where something of a Catch-22 exists. The best time for training a stallion to mount the phantom, Squires says, is the middle of the breeding season, when the stallion's libido is at its highest. The problem is that some mares will have been booked for breeding well before the middle of the season.

Whatever the case might be, proper training of the stallion is paramount, Squires says. In his book Understanding The Stallion, published by Eclipse Press, Squires reports on research at Colorado State (where he spent many years research-ing prior to joining UK) in which he and other investigators examined efficacy of AI collection methods. They found the most effective way for getting stallions to mount and ejaculate the first time was by presenting the stallion to a tease mare, then placing the tease mare parallel to the breeding phantom after he obtains an erection.

Handle With Care

Squires has found that the majority of stallions on large commercial breeding farms are properly handled by experienced personnel. Problems sometimes surface on smaller farms where personnel are less experienced and, in some cases, might even be fearful. He says that demonstrating fear when handling a stallion can serve to stimulate aggressive behavior.

Squires recommends the following:

  • Lead the stallion with a 20-foot leather shank with a short portion of chain. The chain portion should be long enough to thread down one side of the halter and connect to the ring on the opposite side.
  • Place the chain over the tongue in his mouth. A slight tug should cause him to immediately respect the handler.
  • Allow the stallion to be aggressive and do not discourage him from bellowing or obtaining an erection. However, the stallion should never be allowed to endanger the handler/other personnel.
  • The handler should stand beside the stallion with contact between his or her elbow and the stallion's shoulder.

Natural Cover

When preparing a stallion for natural cover, says Samper, the manager should ask two questions. The first question: Has the stallion ever bred mares? (Is he a "maiden"?) The second question: What was the stallion doing before coming to the breeding barn?

If a stallion is fresh off the track, Samper says, he needs a couple of months to recover from the stress of competition and to clear his system of any drugs he received, as well as to allow time for the testicles to return to normal size and function.

Teach the maiden stallion by involving an older, seasoned tease mare that does not kick, bite, or strike when the stallion approaches, says Samper. Handle the stallion with firmness, but not abuse, and allow the horse to carry the breeding act to fruition--mounting, penetrating, and ejaculating.

Generally, Samper says, he will allow the inexperienced stallion to breed the older tease mare on more than one occasion. "One time often is not enough for some horses," he points out. The goal is for the stallion to have a positive breeding experience so that he looks forward to trips to the shed, rather than becoming disinterested.

Stallions should be neither fat nor thin going into the breeding season, but our sources agree these horses might need additional nourishment. The diet depends on the stallion, Samper says. If the horse is highly excitable during breeding season, he will use up more energy than the sedate horse and might need more calories.

Generally speaking, says Squires, caretakers should feed the breeding stallion a ration similar to that of a performance horse that is working relatively hard.

Take-Home Message

There are many things to consider when getting a stallion ready for the shed, so many that books have been written on this subject. Discuss your situation with a reproductive specialist or an experienced stallion manager if you are new to handling stallions or if you have a stud with reproductive problems. The earlier you discover a problem, the more time you have to solve it before your stallion--and your dollars--are on the line in the breeding shed.

About the Author

Les Sellnow

Les Sellnow is a free-lance writer based near Riverton, Wyo. He specializes in articles on equine research, and operates a ranch where he raises horses and livestock. He has authored several fiction and non-fiction books, including Understanding Equine Lameness and Understanding The Young Horse, published by Eclipse Press and available at or by calling 800/582-5604.

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