Horse put down after breaking leg in Calgary Stampede chuckwagon race

A horse was put down Sunday night at the Calgary Stampede after it suffered a broken hind leg during the fifth heat of the chuckwagon races, officials confirmedMonday.

The horse wastaken away in an ambulanceand examined by a veterinarian, who determined it had a severely fractured cannon bone on its left hind leg, the Stampede said in a release.

The veterinarian determined thehorse, part of Roger Moore's team, should be put down.

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"It's not specific tochuckwagonracing, it's just a running injury," said Calgary Stampede spokesperson Kristina Barnes, addingthe horse did not come into contact with anything on the track.

Barnes said the driver, Moore, is a man of few words, but you could see he was visibly upset by the death. She said the Stampede was respecting his privacy following the incident.

Rick Barnett often attends the Stampede and said incidents like this are difficult to watch.

"You know, those kinds of things do happen and it's unfortunate, but they do their best to make it as safe as possible."

After four horses died in the 2015 Rangeland Derby as the chuckwagon races are officially called the Stampede introduced new safety measures, includingnew wagon inspections that test the welds of the vehicles, arebuiltinner rail of the track to prevent erosion during rainstormsand "minor tweaks" to the barrel placements to better align drivers as they come out of the opening figure-eightturns and reduce the chance of collisions.

More recently, the Stampede helped fund research with the University of Calgary, looking at the stress placed on chuckwagonpoles during races.

Cause unclear

"Data is preliminary right now, it's going to progress, we'll have a report in to the Stampede by the end. But what we're finding now, it's not shocking, is that polls are bending during races, but nowhere near the point where they're going to break," said researcher Sam Pollock.

He hopes his work with help refine chuckwagondesign and provide a template for consistency.

It's not yet clear what caused Sunday night's incident.

The Vancouver Humane Society, a long-time critic of the Stampede's rodeo events, tweeted about Sunday's incident, saying60 horses have died in the chuckwagon racessince 1986.

The latest horse death prompted others on social media to call for a ban on the chuckwagon races, which have been a fixture of the Stampede's grandstand show since 1923.