Double Chocolate, a 16-year-old thoroughbred mare ridden by Katrina McQuarters, was eliminated at fence 22 on the cross-country at the Mitavite International Horse Trial at Kihikihi, in Waikato. The horse had completed the first 21 fences clear before being eliminated. McQuarters had dismounted and was leading Double Chocolate home when the horse became distressed and collapsed, according to a statement made by Equestrian Sports New Zealand.
"The treating vet was on hand within two minutes and advised that the horse was already beyond all aid," ESNZ said.
It said the cause of the mare's death was a heart attack.