University of Sydney research has found thoroughbreds that begin racing in Australia at younger ages were more likely to have longer careers than those starting their careers later in life.
In the most comprehensive study yet, the findings showed there was no detrimental effect on a horse’s career if it started racing as a two-year-old.
“This is the largest and most extensive study of its type as we investigated the careers of over 115,000 Australian thoroughbred racehorses and evaluated them throughout a 10 year period,” said Natasha Hamilton, supervising author at the University’s Faculty of Veterinary Science.
Dr Hamilton is co-supervisor of PhD candidate Brandon Velie, lead author of the study published in the Equine Veterinary Journal. The study also used the horse’s exact age at each race as defined by its birth date, rather than simply by year of birth, making it more accurate than comparable studies.
“The survival analysis showed the risk of retirement from racing decreased the younger the horse was when it ran its first race,” Dr Hamilton said.
Risk of retirement also decreased with the number of starts a two-year-old had, and the average distance raced. “Our study supports earlier findings but is based on a much larger sample”, said Dr Hamilton, who alongside her university career has worked as a raceday official for more than 15 years.
Overall, the research suggests that the racing and training of two-year-olds is not harmful as long as there is an awareness that combining an inappropriate training regime with a genetic predisposition to injuries can result in injuries that prevent the horse from continuing or beginning its racing career.