Breakdown injuries in Thoroughbred (TB) racehorses represent an existential threat to the TB horseracing in New York State and throughout North America. These events can be catastrophic or career-ending and have a substantial impact on equine welfare, negatively impact public acceptance of horse racing, and cause severe economic losses for the TB racing industry. Biomarkers that can accurately predict a predisposition for these severe injuries are currently not available. Reliable biomarkers can help veterinarians and trainers to identify horses at increased risk for breakdown injuries and can be used as an indicator for modification of the horse’s training program to mitigate the risk for injury. Our hypothesis is that inflammatory biomarkers can predict breakdown injuries in TB racehorses and their monitoring can help to prevent breakdown injuries from happening. The Specific Aim of this project is to identify predictive biomarkers for breakdown injuries in NYS TB racehorses. We will test serum samples from TB racehorse groups, as defined in the sub-aims below. All samples will be evaluated for a total of 12 inflammatory markers using a novel multiplex assay approach. Inflammatory biomarkers that are easily accessible in equine blood. The goal is to identify the most promising inflammatory biomarker(s) that are associated with TB breakdown injuries. A new inflammatory marker assay for horses was recently developed in the PIs laboratory and normal inflammatory marker values were established. The inflammatory marker assay has been used during the past year for identifying specific biomarkers for several acute and chronic inflammatory conditions in horses through collaborative projects. The diseases we looked at thus far for identification of biomarkers as disease indicators or predictors included arthritis, septicemia, equine asthma, EPM, EHV-1, equine hepacivirus infection, and endometritis. For all of these conditions one or more specific inflammatory biomarkers were identified with marker pattern differing from disease to disease.

During this project, we will use the novel multiplex assay approach for inflammatory markers in four groups of TB horses to identify those that predict breakdown injuries in race horses:
Aim 1a: is to evaluate samples from horses with catastrophic breakdown injuries on NYS racetracks in 2022 and 2023. We expect to collect about 100-150 samples before the horses are euthanized. Aim 1b: is to obtain serum samples from horses with non-catastrophic fractures from Cornell Ruffian Equine Specialists. Samples will be taken before surgery. We expect about 50 samples in 2022. Aim 1c: is to test about 500 samples from NYS race horses that are submitted to the AHDC for the annual Coggins test before the 2022 racing season to obtain specific pre-racing values for this population. Aim 1d: to analyze about 120 samples from clinically healthy and sound 2-year-old horses entering training in 2022 to obtain a ‘healthy racehorse control’ value for all inflammatory markers.

For each inflammatory marker, the four horse groups will be compared using appropriate statistical methods to identify predictive biomarkers for breakdown injuries that can be used to implement safety measures during training to recognize injuries early and to prevent racing of horses with subclinical injuries.

The goal of this project is to identify predictive serum biomarkers for breakdown injuries n horses. These biomarkers can become indicators for recognizing horses that are at risk for breakdown injuries before catastrophic events occur. Predictive biomarkers will benefit the racing industry and prevent future breakdown injuries at racetracks in NYS and beyond.