average lifespan of a thoroughbred horse
Asker's rating. Report Abuse. the average lifespan of a horse is 20 to 25 years...not entirely sure if a racehorses life is slightly shorter or longer...most standardbreds (harness racers) have a much longer career than an average thoroughbred, or quarter horse even though they race as often as weekly...doingitright44 Â· 9 years ago.Thumbs up.sker's rating. Report Abuse. the average lifespan of a horse is 20 to 25 years...not entirely sure if a racehorses life is slightly shorter or longer...most standardbreds (harness racers) have a much longer career than an average thoroughbred, or quarter horse even though they race as often as weekly...