Proactive Management of the Equine Athlete

Competing interests at the heart of equine sports medicine ethics: A scoping review and thematic analysis

BACKGROUND

The ethics of using horses in sport is receiving increasing attention and media scrutiny. Sports medicine ethics is an important and well-established discipline within human medicine and biomedical ethics, which has, thus far, received little application to the equine veterinary field.

OBJECTIVES

The purpose of this scoping review was to explore the existing literature on equine sports medicine ethics, to understand the current concerns and issues, and to map areas for future research.

STUDY DESIGN

Scoping review.

METHODS

Academic databases (PubMed, Web of Science, CAB abstracts) were searched to identify papers, published in English, between 2000 and 2022, that mentioned aspect(s) of the ethics of veterinary provision to the performance horse. Additionally, grey (including lay) literature was identified through global search engines to locate supplementary and opinion articles. Relevant data on article characteristics and ethical concerns were extracted and charted. Thematic analysis was employed to identify key issues.

RESULTS

A literature source of 41 papers/articles was used; of which 35 were from veterinary sources, mostly veterinary journals and conference proceedings. Several themes were identified including: competing stakeholder interests; governing bodies, rules and regulations; provision of optimal veterinary care; confidentiality; and social licence for the veterinary profession. The most commonly mentioned specific ethical concern was the use of medication in performance horses.

MAIN LIMITATIONS

In this scoping review, we have not sought to critically analyse the ethical arguments within the included literature, but rather to collate them so that an overview of ethical concerns can be established.

CONCLUSIONS

Further consideration is required as to how the veterinary profession and sporting governing bodies can support individual veterinary surgeons to strive for the highest levels of professional conduct in equine sports medicine. The veterinary profession should continue to work towards establishing processes for determining what veterinary practices are ethical, optimal, excessive, permissible and impermissible.

Associations between turn out practices and rates of musculoskeletal disease and injury in Thoroughbred foals and yearlings on stud farms in the United Kingdom

BACKGROUND

Early-life locomotor activity during turn out may alter susceptibility to musculoskeletal disease and injury via modulation of behaviours and tissue development during growth.

OBJECTIVES

Investigate associations between turn out practices and rates of musculoskeletal disease and injury in young Thoroughbreds on stud farms in the United Kingdom.

STUDY DESIGN

Prospective cohort.

METHODS

Daily records were kept on location and duration of turn out for 134 Thoroughbred foals on six stud farms, from birth until leaving the farm or study exit. Data on veterinary-attended episodes of musculoskeletal disease or injury were collated concurrently. Average daily turn out times (hours), areas (acres) and group size (n foals) were calculated for rolling 7- and 30-day periods of age. Multivariable Cox regression, including farm as a random effect, was used to investigate associations between turn out practices and musculoskeletal disease and injury.

RESULTS

The overall incidence of musculoskeletal disease or injury was 5.3 cases/100 foal-months at risk (95% confidence interval [CI]: 4.2-6.6). Compared with 24/7 turn out, average daily turn out times of between 9 and 23 hours over a 7-day period were associated with a 4.6-fold increase in musculoskeletal injury rate (95% CI: 1.7-12.3; P < 0.001), adjusting for farm and paddock area. Each 1-acre increase in the average daily turn out area during the 4th month of life, reduced the rate of musculoskeletal disease and injury between 6 and 18 months of age by 24% (hazard ratio 0.76, 95% CI: 0.58-0.99; P < 0.001), adjusting for farm and turn out time.

MAIN LIMITATIONS

Non-random sample of participants may affect generalisability. Use of veterinary-attended events likely underestimates disease/injury rates.

CONCLUSIONS

Results suggest that disruptions or alterations to turn out time routines increase injury risk and should be avoided where possible. Turn out in larger paddocks, particularly before weaning, may confer protection against subsequent musculoskeletal disease and injury.

Champing at the Bit for Improvements: A Review of Equine Welfare in Equestrian Sports in the United Kingdom

Equestrian sports, including racing (e.g., flat, steeple-chasing, harness or donkey derby); show-jumping; cross-country; dressage; polo; polocrosse; endurance; carriage driving; vaulting and hunting; are hugely popular in the UK, and they involve a significant number of people, both as participants and spectators, and tens of thousands of equids. In this paper, we discuss animal welfare as a complex and disputed issue, clarifying what the term means and how it can be measured. We review many aspects of welfare risk to equids used for sport, addressing issues encountered throughout their lives, including housing, feeding, veterinary intervention, shoeing, handling, training, breeding and equipment. This is followed by a unique exploration of the institutions and social processes influencing equine welfare. The institutional components comprise the rules of competition, the equids, attributes of the stakeholders and the space where participants strive to achieve a common purpose. We endeavour to untangle the most significant elements that create barriers or provide opportunities for equine welfare improvement. We expose the challenges faced by a broad range of stakeholders with differing ethics, attitudes and values. Evidently, there are many welfare risks to which equids used in sports continue to be exposed. It is also evident that significant improvements have occurred in recent times, but there remains a barrier to reducing the risks to an acceptable level. We conclude with recommendations regarding a process for change, involvement of stakeholders and management of knowledge to improve equine welfare that involves identifying and prioritising the risk factors and ultimately leading to interventions, further research and/or education.

Retrospective analysis of the population dynamics and racing outcomes of the 2014 and 2015 UK and Ireland Thoroughbred foal crops

BACKGROUND

Up-to-date figures on early losses of Thoroughbreds from the racing industry can inform strategies to improve retention and incentivise traceability of Thoroughbreds during this early life period.

METHODS

Data on Thoroughbred mares bred in 2013-2014 and training, racing and sales information of their live offspring were analysed. The proportions and 95% confidence intervals (95% CI) of the entire 2014-2015 United Kingdom and Ireland foal crops that entered training, raced, were imported and/or exported between birth and the end of their third year of life, as well as the racing performance of these horses as 2- and 3-year-olds were described.

RESULTS

A total of 20,661 mares produced 28,282 live foals. Of them, 47.2% (95% CI: 46.7-47.8; n = 13,354) entered training by the end of their third year of life. Of these, 10,595 (79.3%; 95% CI: 78.7-80.0) raced at least once. Around 20% (n = 5712) of horses were exported by the end of their third year of life, of which 3526 (61.7%) had been in training. The overall mortality during the study period was 7.6% (n = 2123).

CONCLUSION

A considerable proportion of Thoroughbreds had not entered training by 3 years of age but of those that had, the proportion that raced at least once was high. Further research is needed to establish reasons for premature losses from the industry.

Effects of aquatic conditioning on cartilage and bone metabolism in young horses

While beneficial in rehabilitation, aquatic exercise effects on cartilage and bone metabolism in young, healthy horses has not been well described. Therefore, 30 Quarter Horse yearlings (343 ± 28 kg; 496 ± 12 d of age) were stratified by age, body weight (BW), and sex and randomly assigned to 1 of 3 treatments for 140-d to evaluate effects of aquatic, dry, or no exercise on bone and cartilage metabolism in young horses transitioning to an advanced workload. Treatments included nonexercise control (CON; n = 10), dry treadmill (DRY; n = 10), or aquatic treadmill exercise (H2O; n = 10; water: 60% wither height, WH). Horses were housed individually (3.6 × 3.6 m) from 0600 to 1800 hours, allowed turnout (74 × 70 m) from 1800 to 0600 hours, and fed to meet or exceed requirements. During phase I (days 0 to 112), DRY and H2O walked on treadmills 30 min/d, 5 d/wk. Phase II (days 113 to 140) transitioned to an advanced workload 5 d/wk. Every 14-d, WH, hip height (HH), and BW were recorded. Left third metacarpal radiographs on days 0, 112, and 140 were analyzed for radiographic bone aluminum equivalence (RBAE). Every 28-d, serum samples were analyzed for osteocalcin and C-telopeptide crosslaps of type I collagen (CTX-1), and synovial fluid samples were analyzed for prostaglandin E2, collagenase cleavage neopeptide (C2C), collagenase of type I and type II collagen, and carboxypeptide of type II collagen using ELISAs. All data were analyzed using PROC MIXED of SAS, including random effect of horse within treatment, and repeated effect of day. Baseline treatment differences were accounted for using a covariate. There were treatment × day interactions (P < 0.01) where OC and CTX-1 remained consistent in both exercise groups while inconsistently increasing in CON. There were no treatment differences (P > 0.30) in RBAE, BW, or HH, but all increased over time (P < 0.01). There were no treatment × day interactions of synovial inflammation or markers of cartilage metabolism; however, there was an effect of day for each marker (P<0.03). Changes in biomarkers of cartilage turnover in horses exercised at the walk, whether dry or aquatic, could not be distinguished from horses with access to turnout alone. This study indicates that early forced exercise supports consistent bone metabolism necessary for uniform growth and bone development, and that there are no negative effects of buoyancy on cartilage metabolism in yearlings transitioned from aquatic exercise to a 28-d advanced workload.

A prospective cohort study on the acute:chronic workload ratio in relation to injuries in high level eventing horses: A comprehensive 3-year study

In human sport science, the acute:chronic workload (ACWR) ratio is used to monitor an athlete's preparedness for competition and to assess injury risks. The aim of this study was to investigate whether acute and chronic workload calculations for external and internal loads (e.g. high-speed work distance and associated exertional effort) were associated with injury risk in elite eventing horses and to identify workloads performed by horses competing in different competition and at different fitness levels. Training load and injury data were collected from 58 international eventing horses (CCI2*-CCI5* level) over 1-3 years. A total of 94 individual competition seasons were monitored. During this period, heart rate (HR; beat/min) and GPS data were collected of all their conditional training sessions and competitions. External load was determined as the distance (m) covered at high speed (HS¹ ; velocity between 6.6 and 9.5 m/s), and sprint speed (SS² ; velocity>9.5 m/s). Internal load was calculated for HS and SS, using individualized training impulses (TRIMP³ ;AU). For internal and external workload HS and SS the acute (1-week) and chronic (4-week) workloads were calculated and ACWR⁴ determined. The injury data in relation to ACWR was modelled with a multilevel logistic regression. Akaike's information criterion was used for model reduction. Sixty-four soft tissue injuries were registered from a total of 2300 training sessions and competitions. External and internal workload at HS and SS were significantly affected by the year and fitness level of horses. Competition level and year significantly affected the distances covered at SS. The ACWR of high-speed distance of the present week (OR; 0.133, 95 % CI; 0.032, 0.484) and the previous week (OR 3.951, 95 % CI; 1.390, 12.498) were significantly associated with injury risk. Competition level and chronic workload had no significant effect on injuries. In agreement with findings in human athletes, acute spikes of workload in eventing horses increased the risk of injury. Evaluation of horses' workload can be used to design and effectively monitor training programs and can help to improve equine welfare by reducing injury risk.

Commercial equine production in New Zealand. 2. Growth and development of the equine athlete

During the past 20 years, there has been a contraction in the New Zealand Thoroughbred industry and, to a lesser extent, within the Standardbred industry. These changes have seen an increasing proportion of the market being associated with fewer larger commercial farms. Many of these farms manage their own mares, and the mares and foals of several clients. This, in turn, has increased the similarity of the management of breeding and young stock within New Zealand. The temperate climate allows the majority of the management of breeding and young stock to be pasture based. The predominant pasture is ryegrass–clover mix that has been demonstrated to provide adequate nutrition for growth and development. The temperate climate also permits management of horses at pasture year round, which is proposed to stimulate development of the musculoskeletal system. Apart from a brief period during weaning, most young stock remain at pasture from birth until the start of yearling preparation. Free access to pasture exercise provides the opportunity to stimulate the musculoskeletal system for the future challenges as a racehorse. The export focus of many of the equine industries heavily influences the management decisions. Despite the availability of good-quality pasture post-weaning, many foals receive up to 50% of the daily dietary energy requirement as concentrates, possibly reflecting the emphasis on early sales as yearlings and the drive to optimise growth. The observations of drench resistance of common internal parasites presents an emerging problem for pasture-based production systems. A large proportion of the Thoroughbred foal crop is exported as yearlings or ready to run 2-year-olds. There is an increasing trend for Standardbreds to be sold as yearlings and this has resulted in changes in the management of Standardbred young stock.

Equine musculoskeletal development and performance: impact of the production system and early training

The welfare debate around horse racing appears to be focussed on musculoskeletal injury and the racing of 2-year-olds. Much of this debate appears contrary to the evolutionary history of the horse as a cursorial animal and the capability of the equine musculoskeletal system to respond to the demands of race training. Epidemiological studies have reported that 2-year-old racehorses have a longer time period from entering training to the first race and a greater number of lost training days than older horses. However, this is, in part, due to the time taken to learn to train and the impact of dorsal metacarpal disease, which is due to loading of naïve as opposed to immature tissue. Across several racing jurisdictions and codes, it has been demonstrated that horses that train and race as 2-year-olds have longer, more successful, careers than those that start racing later in life. This positive trend has also been observed with horses starting in equestrian sport at an early age. The literature on the growth and development of the horse indicates that the musculoskeletal system is primed for activity and loading from an early age. Additional exercise for the young horse has a positive rather the negative effect, with many tissues having a sensitive period for ‘priming’ when the horse is a juvenile. This implies that under many modern management systems, the challenge to horse welfare is not ‘too much exercise too soon’ but ‘too little too late’. The current limitation in our understanding is the lack of knowledge of what is the correct exercise dose to optimise the musculoskeletal system. Modern management systems invariably provide too little exercise, but is the exercise data from feral horses the ‘gold standard’, or more a reflection of what the horse is capable of if resources such as food and water are limited? Further research is required to refine our understanding of the optimal exercise levels required and development of greater precision in identifying the sensitive periods for priming the musculoskeletal system.

Commercial equine production in New Zealand. 3. The racing and sport industries

The present review examines the commercial production of racing and sport horses in New Zealand, describing the size and scope of the industries, the management and feeding, and the training and wastage of race (Thoroughbred and Standardbred) and sport horses. The number of horses per head of population in New Zealand (30/1000 people) is high by international standards and the main equine industries generate ~2% of national gross domestic product. In New Zealand the Thoroughbred breeding and racing industry dominates organised equestrian activity (economically and numerically). Furthermore, this Thoroughbred bias has an influence on equestrian culture and may explain, in part, the high proportion of Thoroughbred sport horses registered for eventing in New Zealand, which is in contrast to other international sport-horse populations. An understanding of the production, management and structure of the racing and sport industries in New Zealand is paramount to ensure the health and welfare of the equine athlete and the continuing success of the industries.

The Spatiotemporal Characteristics of 0-24-Goal Polo

Global positioning systems (GPS) have recently been shown to reliably quantify the spatiotemporal characteristics of Polo, with the physiological demands of Polo play at low- and high-goal levels also investigated. This study aims to describe the spatiotemporal demands of Polo across 0-24 goal levels. A player-worn GPS unit was used to quantify distance, speed and high-intensity activities performed. Data were divided into chukkas and five equine-based speed zones, grouped per cumulative player handicap and assessed using standardized mean differences. Average distance and speed per chukka increased in accordance with cumulative player handicap, with the magnitude of differences being trivial-large and trivial-very large, respectively. Differences between time spent in high-intensity speed zones (zones 4 and 5) show a linear increase in magnitude, when comparing 0 goal Polo to all other levels of play (Small-Very Large; 6-24 goals, respectively). High-intensity activities predominantly shared this trend, displaying trivial-large differences between levels. These findings highlight increased cardiovascular, anaerobic and speed based physiological demands on Polo ponies as playing level increases. Strategies such as high-intensity interval training, maximal speed work and aerobic conditioning may be warranted to facilitate this development and improve pony welfare and performance.

Living the 'Best Life' or 'One Size Fits All'-Stakeholder Perceptions of Racehorse Welfare

Simple Summary

British horseracing industry stakeholders were asked to discuss their perceptions of racehorse welfare. From the discussions held with stakeholders eight different areas that would have an effect on welfare were pinpointed, with health as the most important. Two strands ran through all eight identified areas. These were health-related factors and the horse-human relationship. In their view, to live the ‘best life’ possible a horse in training should be treated as an individual whereas a ‘one size fits all’ approach best fitted a life lived where minimum welfare standards were in place. Participants highlighted some of the challenges racehorses face in terms of welfare together with any innovative or uncommon practices they had seen used. Health was seen as the most important challenge to welfare as well as being the most innovative, for instance, the continued growth in specialised veterinary treatments. The results from this study can be combined with practical animal welfare evidence to produce the first British racehorse welfare assessment tool.

Abstract

The purpose of the study was to explore the perceptions held by British racing industry stakeholders of factors influencing racehorse welfare. Ten focus groups were held across the UK with a total of 42 stakeholders from a range of roles within racehorse care including trainers, stable staff and veterinarians. Participants took part in three exercises. Firstly, to describe the scenarios of a ‘best life’ and the minimum welfare standards a horse in training could be living under. Secondly, to identify the main challenges for racehorse welfare and thirdly, to recall any innovative or uncommon practices to improve welfare they had witnessed. Using thematic analysis, eight themes emerged from the first exercise. Two strands, factors that contribute to maintaining health and the horse-human relationship ran through all eight themes. Across all themes horses living the ‘best life’ were perceived as being treated as individuals rather than being part of a ‘one size fits all’ life when kept under minimum welfare standards. Health was both perceived as the main challenge to welfare as well as one open to innovative practices such as improved veterinary treatments. Data obtained, informed by the knowledge and expertise of experienced stakeholders, combined with practical animal welfare science will be used to develop the first British racehorse welfare assessment protocol.

Management of the pregnant mare and long-term consequences on the offspring

The study of early developmental conditioning of health and disease in adulthood is particularly relevant in the horse, which is bred mainly to perform in demanding sport challenges. On the basis of this concept, the management of the broodmare could be considered an effective means to produce animals with the desired features. Knowledge on the Developmental Origins of Health and Disease in the equine species remains relatively scarce, with some experimental studies and one single epidemiologic study. Data highlight the determinant role of the maternal environment for postnatal body conformation, immune response, energy homeostasis, osteoarticular status and thyroidal, adrenocortical, and cardiovascular functions of the foal. Most research, however, focuses on the first months/years after birth. Long-term effects on the adult horse phenotype have not been investigated so far.