Pasturing Stallions Together Can Work, Says Study

Behavior Quiz: If you put five breeding stallions together in an open pasture, what do you get? A) the Kentucky Derby, minus the jockeys, B) a new pro basketball team, or C) dramatic chaos?

Believe it or not, according to a new study by a Swiss research team, the answer is D) none of the above. In fact, the scientists, led by Sabrina Briefer, DVM, MSc, researcher at the Swiss National Stud in Avenches, found that within a few weeks, study stallions were not only living as a peaceful herd, but were even showing signs of positive social relationships, such as mutual grooming.

"It had a lot to do with hierarchy," Briefer said. "Once that was established, the stallions seemed to know their place and accept it, and then they were fine."

To carry out the test, the five stallions, which had just finished a season at stud, were brought into individual stalls next to each other in the same stable for one week. During that time they were allowed independent time to discover the 11-acre (4.5-hectare) pasture that they would soon be sharing with the other stallions. When the stallions, ranging in age from 9 to 18 years old, were first released together in the pasture, the researchers were ready with equipment to intervene if necessary.

"But actually, there was no need," Briefer said during the presentation of her results at the Swiss Equine Research Day held April 30 in Avenches. "For the first 45 minutes, there was a lot of squealing, rearing up, bucking, kicking--that sort of thing. But there was never actually any biting or kicking or other physical violence." Once the initial "introductions" were complete, the horses began grazing, she said.

However, it's important to recognize that this kind of "success" might not have been possible if several major safety precautions had not been taken, Briefer said. The stallions were in a pasture far from other horses and especially mares, and they had been given the opportunity to know each other in advance by living in adjoining stalls. All the stallions had their shoes removed, and extra-tall fences were set up around the pasture.

Establishment of hierarchy occurred over a period of several weeks for most relationships, Briefer said, which led toward a linear ranking order. However, the two leading stallions did not display a clear hierarchy between each other until after the first three months.

Living in groups in the pasture led the horses to attribute their time differently to their various activities than when they had been in stalls, Briefer said. This particularly affected how often they ate, stood attentively, and rested.

"The advantages of living in a herd are clear," Briefer said. "Horses are naturally social, and maintaining them in groups is what best meets their needs for physical and mental well-being--stallions included."

Even so, more research is necessary before specific recommendations and guidelines can be made for stud farms and stallion owners, she said.

About the Author

Christa Lesté-Lasserre, MA

Christa Lesté-Lasserre is a freelance writer based in France. A native of Dallas, Texas, Lesté-Lasserre grew up riding Quarter Horses, Appaloosas, and Shetland Ponies. She holds a master’s degree in English, specializing in creative writing, from the University of Mississippi in Oxford and earned a bachelor's in journalism and creative writing with a minor in sciences from Baylor University in Waco, Texas. She currently keeps her two Trakehners at home near Paris. Follow Lesté-Lasserre on Twitter @christalestelas.

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