Researchers from Proteomics International and the University of Western Australia, led by Dr. Christopher James, have developed a simple, stable test that uses a dried blood spot - just a small drop of blood on paper - to measure a specific marker of muscle damage and recovery.
The patented OxiDx test looks at a substance in the blood called thiol-oxidised albumin, a marker of oxidative stress. Oxidative stress occurs when the body’s natural balance is tipped during intense exercise or illness, and it plays a key role in inflammation and muscle repair.
In both humans and animals, higher levels of thiol-oxidised albumin have been linked to muscle damage following hard physical activity. Unlike older tests, such as measuring creatine kinase (CK), this new method is proving to be more sensitive and may detect early or low-level muscle strain that other tests miss.
Blood samples were collected from thoroughbred racehorses before and for seven days after racing. Trainers collected the dried blood spot samples at their stables, making the process simple and stress-free. The researchers also took liquid blood samples on Days 2 and 5 after the race to measure standard muscle enzymes (CK and AST).
The test results showed that thiol-oxidised albumin peaked 2 days after the race, increasing by an average of nearly 4%. Levels generally returned to normal by Day 5, though some horses recovered more quickly or slowly, highlighting individual differences in recovery.
The new test also showed a relationship with AST, another muscle-related blood marker.
Muscle injuries are very common in racehorses. Studies show that up to 85% of thoroughbreds will suffer at least one injury during their 2- or 3-year-old seasons. Often, the signs of muscle strain or damage are subtle or go unnoticed, but continuing to train or race with underlying injuries can lead to reduced performance, more serious muscle damage, such as strains or tears. These may lead to longer recovery times or being withdrawn from competition altogether.
This new test offers a practical way to monitor recovery after each race, helping trainers and vets make better decisions about when a horse is ready to return to training or racing.
This research, published in the journal Veterinary Science and Medicine, suggests that thiol-oxidised albumin could become an important tool for managing recovery and preventing injury in hard-working racehorses.
By tracking how muscle stress builds and resolves after racing, trainers and vets may be able to spot horses that need more rest, or identify those who recover quickly and are ready to safely return to work.
As the racing industry increasingly focuses on welfare, performance longevity, and injury prevention, this test may offer a way to keep horses healthy and at their best.
Proteomics International Managing Director Dr Richard Lipscombe said, “these exciting results mark a significant milestone in applying the OxiDx test to equine veterinary medicine. OxiDx has the potential to empower trainers to monitor muscle recovery with precision, helping their racehorses achieve peak performance while prioritising equine health and well-being.”
The company plan to launch the OxiDx test in Australia later this year
For more details, see:
The level of thiol-oxidised plasma albumin is elevated following a race in Australian Thoroughbred horses
Christopher James, Erin M. Lloyd, Peter G. Arthur
Veterinary Medicine and Surgery (2025)