Most Australian Thoroughbreds are expected to be racing by the age of three, but some have yet to make it on to the track. Indeed, some never have racing careers.
Researchers at the University of Melbourne wanted to learn more about why some Thoroughbreds fail to enter race training before they turn four.
Meredith Flash, Adelene Wong, Mark Stevenson and James Gilkerson, writing in the open-access journal PLOS ONE, noted that there was a lack of data on the barriers for Australian Thoroughbreds transitioning from the stud farm to the racetrack.
They examined the biographical records of Australian Thoroughbred horses born in 2014 to determine the number of horses that had not officially entered race training by the start of their 4-year old racing season (August 1, 2018).
They found that, of the 13,677 foals born in 2014, 66% had started training and 51% had raced before the beginning of their 4-year-old season in Australia.
The authors selected a geographically representative sample of the 2014 Thoroughbred foal crop of 4124 animals, of which 1275 horses were identified by the records as having not entered training.
Their breeders were sent an online questionnaire, with follow-up phone calls for those who had not responded, to learn the fate of the horses.
In the end, they received 633 responses (50%).
The study team expected each horse to fit into one of four categories:
- Alive and active within the Thoroughbred racing industry;
- Alive and active outside of the Thoroughbred racing industry (for example, being used a pleasure horse);
- Exported; or
The researchers found that 239 of the 633 horses (38%) had died, with just over half (52%) dying in the first 12 months of their life, with the first week being the most critical.
Across all 239 deaths, fractures claimed 44 horses under 12 months of age, with 33 suffering a similar fate over the age of 1.
The most frequently reported cause of death in horses younger than one year of age was congenital malformation.
Eight percent (19) of the 239 horses who died were reported as having done so during unofficial training or pretraining, without ever registering a stable return with Racing Australia, the authors said. Five of these horses were reported to have died at one year of age, seven at two years of age, and seven at three years of age.
Traumatic causes of mortality, including fracture, tendon/ligament injuries, wounds/trauma or horses that had multiple traumatic injuries, were reported for 32% of deceased horses (77 animals). This included horses where respondents selected multiple causes of death.
Nineteen percent (15) of the 77 traumatic injuries were reported to have occurred during training/pretraining, although there was no official record of these horses having entered training.
The remaining 81% of traumatic injuries, involving 62 animals, were due to paddock accidents or misadventure-type incidents.
Overall, 73% (175) of deceased horses died under 2 years of age. These horses were not old enough to be eligible to start in a race at the time of their death.
Involved in racing
Twenty-four percent of the 633 horses (154) were categorised as actively participating in training or racing activities, despite no record of this activity in an official racing database at the time of selection for the study.
Eighteen percent of horses (117) were categorised as actively participating in race training in Australia as a four-year-old at the time of the survey, and 6% (37) were categorised as spelling, based on the assumption that a spelling horse must previously have undergone some form of training or pre-training.
Thirteen percent of the 633 horses (84) were categorised as having been sold at public or private sales. About half were sold as yearlings. Those surveyed often indicated that they were not aware of the outcome for horses once they had been sold.
Just one of the horses was categorised as having been exported.
The authors noted a loss of traceability at the point of sale.
Rehomed or retired
Thirteen percent of the 633 horses (83) were categorised as having been rehomed or retired, with 61% having never undergone any form of official training or pretraining.
The main reasons for being rehomed or retired were due to an illness or injury followed by poor performance.
The most common types of injuries were tendon/ligament injuries (7 animals) followed by congenital malformation (6) and wounds or trauma-related injuries (5).
It seems that respondents tended to use “congenital malformation” and “conformation fault” interchangeably, with “bad knee conformation”, “weak hocks” and “born premature” categorised as congenital malformation.
Horses were mainly rehomed into equestrian or pleasure pursuits, followed by companion and other unridden activities. For horses that were categorised as rehomed to equestrian or pleasure pursuits, pleasure horse or hack was the most frequent category, followed by pony club, adult riding, dressage and showjumping.
A further 3% of horses (20) were categorised by survey respondents as having a status other than the options listed in the survey, and were being held with an intent to race.
“Respondents indicated that these horses had not yet entered training because of financial or personal reasons, they had wanted the horse to grow and mature, or the horse had experienced an injury when it was young. Some did not provide an outcome reason,” the researchers wrote.
In all, the fate of 6% of the horses (35 animals) was reported as unknown. Those surveyed either indicated that they could not remember, did not know the outcome, or did not select an outcome.
The researchers expanded the numbers, based on the proportions obtained from the 633 horses that did not race before their four-year-old season, to see how the numbers would look across the 2014 foal crop.
They extrapolated the survey results out to the 3878 horses that had not registered an official stable return before August 1, 2018. The table below shows the results.
Discussing their findings, the researchers said that, as a whole, the survey results indicated that most deaths occurred due to non-training related illnesses or injuries.
“Research is needed to investigate how stud farm design and infrastructure are associated with risk of fatality in horses,” they said.
They said that while official race records provide an accurate indication of the number of horses that start in a race, industry data underestimates the proportion of the national foal crop that enters training.
Flash ML, Wong ASM, Stevenson MA, Gilkerson JR (2020) Barriers to entering race training before 4 years of age for Thoroughbred horses born in the 2014 Australian foal crop. PLoS ONE 15(8): e0237003. https://doi.org/10.1371/journal.pone.0237003