The Stampede says the death of an outrider’s horse at the chucks Friday night appears to have been from natural causes.

However, spokesperson Bonni Clark says a post mortem exam will be done to pinpoint exactly what happened.

She says the 12 year-old thoroughbred with Doug Irvine’s team collapsed just after the end of the fourth heat, and the vet determined the horse died immediately.

Clark says the animal had also been examined prior to the race and had not shown any signs of illness.

The death of the outrider horse and the previous death of the steer during the steer wrestling competition has animal rights groups speaking out.

Spokesperson for the Calgary Animal Rights Coalition Michael Alvarez-Toye says there is nothing natural about what the animals are put through.

“A horse knows instinctively when to ease off if it’s running in a natural environment.  Here, there’s nothing natural about it, it took place in an arena where they are goated into running alongside or in front of chariots run by a team of horses that are being whipped and compelled to run faster, and in tighter turns.  So there is certainly nothing natural about that.”

He goes on to say the deaths of the steer and now outrider horse are inevitable, and the only way to stop the deaths, is to stop the events.