Veterinary Management of Thoroughbred Yearlings after Sales

Who hasn’t heard a story about a yearling or young horse that failed its vet check at the sales but went on to become a champion?

It’s definitely not an exact science, and there are many variables as to why a horse will or won’t be a successful racehorse. But veterinary medicine has come a long way and is getting better all the time at the assessment of young horses to help buyers and vendors determine the risks associated with purchase for future athletic performance. These assessments also have a significant effect on the price horses achieve at sales time. 

So, whilst there will always be exceptions to the rule, it's probably equally important to understand that these are exceptions and that generally speaking, we should be able to agree that veterinarians are now much more skilful at determining the significance of certain issues. 

Veterinary examinations at yearling sales.

Diagnostic tools used at yearling sales frequently include radiography (fetlocks, knees, hocks, stifles, and feet), endoscopy, and ultrasound. Each of these will provide important information for the veterinarian, although several other factors may still influence their final opinion as to the associated risk. These take into account things like breeding and type, the likely training and racing environment the horse will end up in, the ability to sell on in the future, and the clinical experience of the vet and purchaser themselves. All these will combine and ultimately allow the veterinarian to apply their own clinical judgment at the time of sale as to the suitability for purchase. 

Common problems detected that are associated with horse's joints include supracondylar lysis, OCD (osteochondrosis), bone fragments, ligament injuries (entheseopathy), subchondral bone cysts, and osteoarthritis. We will not attempt to discuss the significance of each of these in this article as there are plenty of references available to do that. But there is an opportunity to raise awareness of how vendors, purchasers, and veterinarians can perhaps consider a more proactive approach in the subsequent management of certain orthopaedic lesions given the recent advances in veterinary medicine now available. 

Veterinary intervention in management of yearlings post sales. 

Once a horse is purchased it is often sent off for a period of rest before it is expected to enter an early pre-training period, normally as a rising 2-year-old at approximately 18 to 22 months of age, depending on birth dates. This is an ideal time for the owner, trainer, and veterinarian to review the information that was gathered at sales time. This can then be used to identify any critical areas or joints that may need particular attention during training and to repeat any diagnostic tests, especially radiographs, to assess any changes that may have occurred over time since the sales. 

The key here is that early treatment intervention, especially during this period before pre-training, is now a very real option for young horses. Regenerative therapies using biotechnological substances such as gene therapy, recombinant or autologous growth factors (platelet-rich plasma, autologous conditioned serum- IRAP, and Alpha-2 macroglobulin) and stem cells (allogenic and autologous) are now much more accessible and do not carry the same associated risks or contraindications that were present historically with the likes of corticosteroids in young animals. 

Another novel product now available for veterinarians is Arthramid Vet, a 2.5% polyacrylamide hydrogel (PAAG), registered for use by vets in osteoarthritis treatment. This unique hydrogel once injected into the joint, acts as a bio-scaffold that in turn increases the elastic strength of the joint capsule and provides active cushioning. It also results in the formation of a novel synovial cell membrane layer lining the joint, likely resulting in an improvement in joint fluid quality and prolonged visco-supplementation effects. Published studies have certainly shown it to be superior and longer-lasting than conventional treatments like corticosteroids and hyaluronic acid for resolving lameness associated with osteoarthritis and, if administered early on in the disease process, to act as a preventative to disrupt the otherwise degenerative cycle of arthritis. 

A prophylactic approach to joint health

A prophylactic approach at this early stage may well help reset the course of orthopaedic disease development for the equine patient. 2.5% PAAG may also be considered as adjunctive therapy to support joint rehabilitation following surgery for conditions like OCD and even subchondral bone cysts. Surgical intervention is commonly employed for certain lesions such as OCD fragmentation and may explain why these are less commonly associated with poor performance later in life. If a horse has had surgery then this must be disclosed at the time of sale and enables the veterinarian to make an informed decision as to the future management of that joint. Any sites where OCD surgery has taken place should be reassessed early in the pre-training period and the opportunity for early treatment intervention to occur as necessary, while still taking into consideration the overall management of the horse. 

The latest joint care treatments for horses

New treatment options like 2.5% PAAG are proving a game-changer in how veterinarians can better manage joint disease and associated lameness in young horses. Anything that can alter the progression of a disease, or reduce its consequences once established deserves consideration. Treatments that can be directed at the different phases in the development of a disease, with the aim of eliminating or minimizing its impact, or retarding the progress of disease and disability are desirable. In turn, this leads to improved welfare and safety and, allows young horses the best opportunity to reach their performance potential.  

The challenge in preventative approaches relates to ethical considerations and the evidence base of preventative intervention. But the opportunity is to process the information we do have and make the best decisions along the way, gathering more information as required, and making the right treatment decisions at each critical time point. New technologies and advances in veterinary medicine like 2.5% PAAG are now allowing us to adopt a proactive or preventative approach to joint care and with the potential for major positive implications for ongoing joint health and horse welfare. 

Dr Jason Lowe, Equine Veterinarian and CEO of IMS Vet.