Relevance of equine doping for welfare

Doping and doping control both have potential to significantly impact horse welfare in negative ways. The former is, clearly, unregulated and unlikely to ever have the horse’s best interest at heart. Conversely, doping control, which is all about protecting the horse, must be balanced to achieve its objective while having minimal impact on legitimate use of effective therapeutic medicines.

Doping of horses is undertaken to alter the performance of the animal with the intention of yielding monetary or social reward for the culprit. Horses may be doped to enhance or supress their performance, the latter where the reward from betting income exceeds that from prize money. An injured horse may be cynically administered a legitimate therapeutic agent to disguise pathology from which it is suffering, in order to circumvent regulatory checks or in an attempt to restore its normal performance. Drugs, such as furosemide, may be used to mask the use of doping agents by increasing urine output and, thereby, dilution of the illicit agent.

There are many different drugs that have been used to enhance performance over the years. Manipulation of the horses’ genome to alter an animal’s physique, to increase production of endogenous agents that impact metabolic processes or manipulate pain tolerance are increasingly relevant.

Performance enhancing drugs may stimulate a horse to perform beyond its natural physiological limit, increasing the risk of injury and disease in the process. The drugs themselves may cause disease through direct pharmacological effects. Use of analgesics and anti-inflammatory drugs used to mask disease or injury increase the risk of catastrophic musculoskeletal injury and are likely to exacerbate existing pathology.

Drugs used to suppress performance may have direct negative effects and may also increase the risk of an accident in competition, causing injury to the doped horse and those in close proximity

Gene doping is associated with a range of additional threats to horse welfare, especially in a totally unregulated environment. Immune responses to vectors used to transfer genetic material and to transgene expression have been documented in humans and other animals. Vector integration, predisposing to cancerous mutation, overexpression of transgenic proteins and severe side-effects have also been recorded. Furthermore, the integrity of the natural genome may be damaged if genes in germ line cells are interfered with.

The distinction between “doping” and the legitimate use of therapeutic agents to care for horse welfare can be controversial. Many racing jurisdictions are full signatories to the guidelines documented in article six of the International Agreement on Breeding, Racing and Wagering of the International Federation of Horseracing Authorities, which requires zero tolerance towards presence of prohibited substances in horses at the time of competition. However, some would argue that temporary cessation of administration of drugs such as omeprazole, in order to comply with this rule may not be in the best interests of the horse. Nevertheless, racing authorities and analytical laboratories in relevant countries go to lengths to establish realistic screening limits for therapeutic medications, which set levels of detection (screening limits) at a point that allows valid use of the medication as late as possible while ensuring that the therapeutic effect of any residual drug at the time of competition is negligible.

Dr Chris RIGGS

BVSc, PhD, DEO, DipECVS, FRCVS

Chris studied Veterinary Science at the University of Bristol, UK, in the early nineteen eighties. He received further training in Equine Surgery at the Royal Veterinary College, UK and was awarded a PhD for research into the causes of racehorse fractures in 1991. He subsequently worked as a Senior Lecturer at the Philip Leverhulme Equine Hospital, University of Liverpool, where he developed specialist skills in equine surgery. He gained further clinical experience at several equine referral centres in the United Kingdom and Australia before joining the Hong Kong Jockey Club as Head of Veterinary Clinical Services in 2003. He was appointed to a new role in the Club as Director, HKJC Equine Welfare Research Foundation/ Chief Advisor, Mainland Veterinary Engagement in 2019.

Chris has a particular interest, and specialist qualifications, in surgery and orthopaedics. He has published over 80 scientific papers about fatigue damage in bone and its role in racehorse fractures, among other topics. He also cares deeply about helping to provide opportunities for young colleagues to further their clinical skills, with a focus on Mainland China.

Chris is a Fellow of the Royal College of Veterinary Surgeons, UK and holds positions as Adjunct Professor at the College of Veterinary Medicine and Life Sciences, City University, Hong Kong, Special Professor at the School of Veterinary Medicine and Science, University of Nottingham, UK, and Guest Professor at Inner Mongolia Agricultural University.