The World Professional Chuckwagon Association says Dr. Doyle Mullaney died Sunday of an apparent heart attack.
The association says Mullaney had the heart attack while battling a grass fire near his home in Hartell, Alta., southwest of Calgary.
He was 68.
The association says Mullaney was affectionately known as "Doc" or "Colourful Irishman" and had recently celebrated five decades on the chuckwagon circuit.
It says he was a great ambassador to chuckwagon racing.
Mullaney recently celebrated 50 years in the chuckwagon business after his annual trip to the Houston Astrodome to run pony wagons this past winter.
He was a second generation chuckwagon man who started his career as a chuckwagon driver and outrider in 1964 as part of Cliff Claggett’s legendary barnstorming chuckwagon show.
Mullaney also competed in bull riding and bareback bronc riding, and graduated from Western College of Veterinary Medicine in 1973.
He owned and operated the Big Rock Animal Clinic in Okotoks, Alta., until he sold his practice in 2010.
Mullaney also participated in numerous parades and exhibitions, including driving chuckwagons as part of the opening ceremonies at the 1988 Winter Olympics in Calgary.