Endurance Horses Research Articles

Type, prevalence, and risk factors for the development of orthopedic injuries in endurance horses during training and competition.

To report the type, prevalence, and risk factors for the development of orthopedic injuries in endurance horses. 235 endurance horses. Medical records of horses examined between January 2007 and December 2018 were reviewed. Recorded data were birth; breed; sex; dates of first and last examinations; presence of any conformation fault, lameness, positive flexion test result, and orthopedic injury; starts in endurance competitions; level of athletic activity; professional status of trainer or rider; and whether an orthopedic injury developed in > 1 limb or during or within 2 days after competition, lameness resolved after treatment, reinjury occurred, horse was eliminated from competition after treatment, and the horse required retirement from endurance competitions. Anatomic locations of injuries were classified as proximal portion of the metacarpal area, midportion of the metacarpal area, metacarpo- or metatarsophalangeal (fetlock) area, tarsus, or foot. For each outcome, multivariable logistic regression models were developed after bivariable logistic regression and collinearity analyses. 351 orthopedic injuries were detected in 76.6% of the horses, with 27.1% that affected the fetlock area, 21.4% the proximal portion of the metacarpal area, 21.1% the foot, 12.8% the tarsus, 9.1% the midportion of the metacarpal area, and 8.5% other sites. High suspensory disease (21.4%) was the most common condition, followed by arthropathy of the metacarpo- or metatarsophalangeal joint (19.4%) and solar pain (14%). Age at first examination (OR, 1.70; 95% CI, 1.37 to 2.11), months of observation (OR, 1.03; 95% CI, 1.01 to 1.05), conformation fault of forelimbs (OR, 4.08; 95% CI, 1.53 to 10.89), and amateur status (OR, 2.62; 95% CI, 1.86 to 7.99) remained significant in the final multivariable regression model for the development of orthopedic injuries. A large number of endurance horses developed ≥ 1 orthopedic injury during training or competition. Clinical and diagnostic examinations should be focused with particular attention to the metacarpophalangeal joints, proximal portion of the metacarpal area, and foot.

64 Feeding elite equine athletes: Perspectives from high-goal polo and endurance riding competitors

Knowing equine stakeholder feeding practices can better inform research, extension, and education programs. The objective of this exploratory survey was to describe feeding management and activity of horses performing at elite levels in polo and endurance riding. High-goal polo participants were targeted for survey distribution through a polo magazine publication during the winter of 2018. A researcher recruited endurance riders to participate at an American Endurance Ride Conference sanctioned event held in Florida during March 2018. Participants were contacted 3 times to complete a questionnaire to describe horse management practices, dietary information, and preferences with regards to equine nutrition. Eight of 11 (72.7%) polo players and 9 of 22 (40.9%) endurance riders completed the survey. Seventy-six percent of barns (13/17) were located in Florida at the time of survey completion. To compare disciplines, continuous data were analyzed using t -test and categorical data using a Mann-Whitney U-Test. Polo ponies were fed alfalfa hay, with 50% (4/8) of respondents predominately feeding alfalfa hay, and the remaining feeding alfalfa/grass hay mixtures. Endurance horses were more likely ( P = 0.056) to have ad libitum access (7/9) to forage than polo ponies (2/8), likely because most endurance horses were housed on pasture (6/9). For hay, nutritional value was extremely important in forage selection decisions for both polo and endurance sports. Polo respondents were more likely to value ( P = 0.018) forage color and smell than endurance participants. All respondents reported feeding their horses grain or concentrate, a typical recommendation for feeding horses with elevated nutrient requirements due to increased workload. Nutritional value was the most important factor for selection of grain or concentrate, followed by feed availability, veterinarian or nutritionist recommendation, feed manufacturer reputation, cost, or industry professional recommendation, in order of preference. Polo ponies worked an average of 51 ± 24 min/d (STD DEV) 6 times per week. Endurance horses worked longer (115 ± 52 min/d, P = 0.007) but less frequently (4 times per week, P = 0.001) than polo ponies. Polo ponies tended to compete more frequently (3.9 ± 2.3 times per month, P = 0.101) than endurance horses (1.8 ± 0.7). During a race, endurance horses were fed more frequently and offered different feeds than the typical ration. These data indicate feeding management preferences are specific to athletic activities. Widespread use of this questionnaire could help target equine educational programs to the needs of the industry.

Plasma Activin A and Decorin in Exercised Purebred Arabian Horses – Preliminary Study

Development of the musculoskeletal system occurs, in part, through an impact on regulatory proteins, such as activin A and decorin. Activin A induces atrophic effects on skeletal muscle, and decorin regulates the formation of connective tissue proteins like collagen and elastin in tendons and ligaments. The aim of this study was to evaluate the influence of different intensities of exercise on blood plasma activin A and decorin concentrations in horses. Ten young purebred Arabian horses were subjected to routine training sessions on a racetrack, and another 11 adult horses of the same breed participated in endurance rides. Race horses were examined during gallop tests over a distance of 1200 m and endurance horses at distances from 20 to 80 km. Blood samples were collected at rest and after exercise to determine plasma concentrations of activin A, decorin and cortisol. Despite differences in the intensity of exercise, the plasma decorin concentration remained unchanged, and activin A tended to decrease in endurance horses only. The exercise-induced changes in plasma activin A concentrations correlated with the covered distance (r = -0.43; P < .05), but not with the changes in cortisol values. Further studies are needed to confirm the usefulness of plasma activin A as a potential indicator of a horse's endurance performance.

The Physical Activity-Dependent Hematological and Biochemical Changes in School Horses in Comparison to Blood Profiles in Endurance and Race Horses.

Simple SummaryLeisure horse riding is a leading branch of the equine industry worldwide, thus, horses are used for pleasure and in riding schools represent a much larger group than sports horses. Nevertheless, still little is known about the physiological demands and the nature of the exercise metabolism in school horses. The exercise capacity in sport horses is routinely monitored using blood tests including hemogram parameters and selected biochemical indicators. This study aimed to measure the physical activity-dependent blood indicators during the leisure type of work in riding schools in order to compare them with endurance and race horses’ effort-dependent profiles. The similarities between school and race horses in a high level of erythrogram parameters after effort as well as between school and endurance horses in a high level of white blood cell count and high activity of creatine phosphokinase after effort were demonstrated. However, the fluctuations in physical activity-dependent blood indicators were lower in school than in professional equine athletes. The exception was the lactic acid profile, which achieved higher values than in endurance horses and lower than in race horses. Limiting the school horses monitoring to only the endurance or racing blood profile may result in the omission of significant changes in hematological and biochemical parameters.Blood testing is one of the most important ways to improve performance, facilitate recovery and monitor the training of endurance and race horses. However, little is known about the physical activity-dependent changes of blood parameters in horses used for pleasure and in riding schools. This study aimed to perform routine blood tests for training monitoring of sport horses in three different horse types of use. Then the values of blood indicators were compared between school, endurance and race horses to find similarities in the physical activity-dependent profile. The study was carried out on 15 endurance, 15 race and 15 school healthy horses who underwent the typical effort for their disciplines. The hemogram parameters, creatine phosphokinase (CPK), aspartate aminotransferase (AST), blood lactate (LAC), and total serum protein (TSP) concentrations were measured using the same protocol and equipment. Measurements of main hematological and biochemical physical activity-dependent parameters were conducted before, immediately after and 30 min after training. In school horses, the physical activity-dependent increase of WBC (40.9%) and CPK (76.4%) was similar to endurance horses, whereas an increase of RBC (19.1%), HGB (18.6%) and HCT (19.4%) were more similar to race horses. The moderate effort-dependent increase of LAC concentration (2775%) was lower than in race horses (7526%) and higher than in endurance horses (390%). Limiting the training or work monitoring assessment of school horses to only the endurance or racing blood profile may result in the omission of significant changes in hematological and biochemical parameters.

Speed and Blood Parameters Differ between Arabian and Žemaitukai Horses during Endurance Racing.

Simple SummaryLimited information exists on the physiological changes that occur in the horses competing in endurance races. The objective was to provide the initial data describing changes in laboratory measurements of the horses competing in endurance races under temperate conditions and to compare the data between the Arabian horses, which are one of the most popular horse breeds in the world, and a Lithuanian horse breed—Žemaitukai. The study was carried out on 112 horses. Blood samples were collected before and after an endurance race. The Arabian horses were faster compared to the local breed (Žemaitukai). The study showed significant changes in horse blood gasometrical and biochemical indicators.Fédération Equestre Internationale (FEI) has described equine endurance racing as the second largest discipline in the world, above which is only show jumping. The Žemaitukai is an ancient indigenous Lithuanian horse breed known since the 6th or 7th century. The Arabian horse breed is one of the oldest human-developed horse breeds in the world. Compared with other race horse breeds, the muscle tissue of Arabian horses is characterized by significant differences in structure—a predominance of oxidative fiber type I is observed in Arabians, making them the prevailing breed in endurance racing. The Arabian horses are recognized as the leading breed in endurance competitions. Speed, pace, and total time in the race strategy have been extensively studied in human sports, and in contrast, this strategy appears to have been virtually ignored in equestrian sport, despite the potential for contributing to performance optimization. In relation to speed and total time in the race, there are limited data on postrace physical, biochemical, and blood gas parameters of endurance horses. Thus, this study was carried out to investigate the effects of speed on the blood parameters of the Arabian and Žemaitukai horses during an endurance race. Blood samples were taken before and immediately after the exercise. Biochemical and blood gas indicators were analyzed. The study showed significant increases in mean blood gasometrical indicators, such as partial carbon dioxide pressure (8.09–15.18%, p < 0.001); base excess in the extracellular fluid (14.01%, p < 0.001 in the Arabian horses and 172.01% in the Žemaitukai breed, p = 0.006); decreases of the blood electrolyte ionized calcium (4.38–8.72%, p < 0.001) and the hematocrit and hemoglobin values (20.05–20.12%, p < 0.001 in the Arabian horses and 6.22–6.23% in the Žemaitukai breed, p = 0.003–0.004); and decreases in the base excess in the blood values (29.24–39.38%, p < 0.001) and lactate (13.45–31.97%, p < 0.001) in the blood of both breeds in the post-competition horses. Significant increases after competition were determined for the values of creatinine (21.34–30.82%, p = 0.001–0.004), total bilirubin (50.84–56.24%, PH < 0.001), and albumin (2.63–4.48%, p = 0.048–0.001) for both breeds. For the faster Arabian horse breed, recovering after racing took half the time that the local Žemaitukai breed did.

The Ridden Horse Pain Ethogram

SummaryThe Ridden Horse Pain Ethogram (RHpE) comprises 24 behaviours, the majority of which are at least 10 times more likely to be seen in lame horses compared with non‐lame horses. The observation of ≥8/24 behaviours is likely to reflect the presence of musculoskeletal pain, although some lame horses score &lt;8/24 behaviours. A marked reduction in RHpE scores after resolution of lameness using diagnostic anaesthesia proves a causal relationship between pain and RHpE scores. Horses should be assessed for approximately 10 min in walk, trot (including 10 m diameter circles), canter and transitions. The validity of the RHpE has been verified for use in horses which perform dressage‐type movements, and which have been trained to work with the front of the head in a vertical position. It has not, as yet, been used in horses while jumping, racehorses, western performance or endurance horses. The RHpE provides a valuable tool for riders, trainers, veterinarians and other equine professionals to recognise the presence of musculoskeletal pain, even if overt lameness cannot be recognised. Riders with a higher skill‐level may improve gait quality, but cannot obscure behavioural signs of pain, although specific behaviours may change. Tight saddle tree points, the rider sitting on the caudal third of the saddle and rider weight may influence RHpE scores. Accurate application of the RHpE requires training and practice. The RHpE is a powerful tool for the assessment of ridden horses and the identification of likely musculoskeletal pain. Such pain merits further investigation and treatment, to improve equine welfare and performance. The RHpE provides an additional means of evaluating the response to diagnostic anaesthesia. It provides a mechanism for client education and a diplomatic way of communicating with clients about equine discomfort related to saddle‐fit, rider size, their position in the saddle and ability to ride in balance.

Stress response after race and endurance training sessions and competitions in Arabian horses

Assuring a high level of animal welfare is a critical aspect of contemporary animal husbandry. Equine athletes begin their careers at a very young age when they are still developing and they are both physically and mentally immature. Lack of scientific knowledge of the stress related to horse racing impedes the development of optimal training programs to attain equilibrium between the best sport results and optimal welfare. This study aimed to determine the influence of the intensity and type of physical activity on peripheral blood cortisol concentration. Thirty untrained Arabians, 9 endurance and 21 race horses were enrolled in this longitudinal study. Blood samples were analysed every 3-weeks in 4 training sessions and 2 races in racing horses and monthly after 2 training sessions and 1 competition in endurance horses. Cortisol concentration was measured at rest and 30 min. after physical effort. Racing horses were divided into two groups of the best and the worst performers.Cortisol concentration increased significantly after training and competition, however both in racing and endurance horses the increase was more intensive after competition. In the racing horses, cortisol concentration tended to gradually increase after the subsequent trainings during the racing season, however the starting gate did not appear to exert any impact on cortisol concentration. The best performing race horses appeared to have a lesser increase in cortisol concentration after the race than the worst performing horses, however the cortisol concentration after the race was not significantly different between these two groups of horses.This study suggests that an optimal training program can induce a stress response which is likely not to have any harmful impact on an athlete’s welfare. The more intense effort associated with competition events, both in race and endurance horses, results in a greater stress response, indicating that these kinds of events should be limited to assure animal welfare. Finally, better performance horses adapt more readily to physical activity as they experience less increase of serum cortisol concentration after the race.

Indicators of exhaustion and stress markers in endurance horses

Prolonged training and physical effort in endurance horses can influence the performance of the endurance horses negatively. The negative impact of the event is especially noticeable if venues are demanding, i.e. bad weather conditions or demanding grounds, high altitude and especially in cases of insufficiently fit horses. One of the most important factors that influence equine performance is abundance of oxygen in the blood, which is directly related to the air oxygen content and changes with atmospheric pressure, so that high altitude and low air pressure demand additional work from horses and accelerate fatigue. The authors goal was to investigate the influence of workload in endurance racing on sport horse organism. A total of 18 trained and competing endurance horses enrolled in a 60 km long endurance race organized on Zlatibor Mountain were included in our survey. Due to the difficult track 8 horses were disqualified due to lameness, and high heart rate and respiration. Only 10 horses completed the race and these animals were submitted to basic physical, clinical and laboratory examinations, in order to evaluate fatigue and stress reaction in endurance horses in Serbia. Results of the clinical and laboratory testing obtained show significant changes in all parameters evaluated which we attributed to physical effort in all 10 horses that finished the race in comparison with the values obtained before the race. In conclusion, 10 horses finished the race and were tested, and they indicated significant alterations in physiological parameters showing stress reaction. The evaluated parameters decreased into physiological interval values during the 5 days following the race.

Diseases of clinical relevance in endurance horses

Diseases of clinical relevance in endurance horses

SHORT­TERM TRAINING PROGRAM FOR THE PREPARATION PERIOD IN THE ENDURANCE DISCIPLINE OF EQUESTRIAN SPORT

ABSTRACT The competitive pairs of horse and rider in the endurance discipline of equestrian sport in Bulgaria have ranked, in the past several years, among the elite contestants in Europe and the world, which has necessitated deeper studies in the areas of training methods and the ways of achieving high sport results. Therefore, this study is focused on 6 Bulgarian horses (Arabian horse and Shagya, Table 1) that are preparing for European and World championships. They were trained together under the same conditions (climate, time zone, terrain, speed) by riders with the necessary qualifications and experience. Seven training rides were performed, and the pulse was measured at the moment of the highest load, as it is the most indicative of the horse’s level of effort. By studying the pulse of horses during a training session, the research aimed to determine the efficacy of the short-term training program in the prep season. The results showed that 2 to 4 minutes after coming to a full stop, regardless of the terrain, speed (in this research between 5.2 km/h and 22.5 km/h) or distance traveled by the horses, their pulse varied between 36 and 99 bpm (beats per minute) and they improved their physical condition and increased their stamina without this leading to trauma or more serious injuries, which is a main priority in the equestrian sport and allows for the successful completion of every race. In the long run, such a training methodology will allow the horses to be trained and ready to race at any time. Monitoring the heart rate and keeping it within the studied limits showed that this was the optimal option for a training regime for the six examined horses. In the situation with the COVID19 pandemic, this is a possible solution for maintaining athletic fitness in endurance horses.

Concentrations of Circulating Irisin and Myostatin in Race and Endurace Purebred Arabian Horses—Preliminary Study

Simple SummaryIrisin and myostatin are regulatory proteins produced by muscle cells. The aim of the study was to evaluate the effect of exercise on plasma irisin and myostatin concentrations in horses in different types of training (speed versus endurance). To find out, we tested 20 Arabian horses, submitted to the two different equestrian disciplines, and consequently different training regimes. The first group of horses realized a short-term, high-speed bout of exercise whereas the second group of horses were submitted to long-lasting, endurance effort. The obtained results showed that the single bout of exercise induced an increase in plasma myostatin concentration. Plasma irisin level decreased during the race season in racehorses. This means that irisin and myostatin may play a regulatory role in the maintenance of the energy balance processes. Skeletal muscle is considered to be the largest endocrine organ determining the maintenance of energy homeostasis. Adaptive changes in skeletal muscles in response to physical exercise influence the production as well as secretion of myokines, which are bioactive factors that play a crucial role in energy expenditure processes. The aim of the study was to investigate the impact of two different types of exercise on the circulating level of two of these, myostatin and irisin, in trained horses. Twenty purebred Arabian horses were involved in the study: 10 three-year-old horses trained on the racetrack and 10 endurance horses aged 7.4 ± 1.9 years. The horses from both groups were regularly trained throughout the entire season, during which they also participated in Polish National competitions. To assess the influence of the training sessions on plasma myostatin and irisin concentrations, blood samples taken at rest and 30 min after the end of exercise were analyzed. In the studied horses, the single bout of exercise did not influence plasma irisin but induced an increase in plasma myostatin concentration. In racehorses, plasma irisin concentration decreased with the length of the training season. Plasma myostatin was higher in endurance horses than in three-year-old racehorses. Lack of exercise-induced fluctuation in circulating irisin in studied horses suggests that myostatin released in response to exercise provides a negative feedback signal to irisin release.

Effect of racetrack surface on glycolytic activity of trained endurance horses

ABSTRACT No study has analysed the effects of wet and dry racetrack surface on the glycolytic activity of Arabian horses. The aim of the present study was to investigate the effects of wet and dry racetrack surfaces during a riding test in an Arabian endurance horse. Using a counterbalanced design, nine healthy and trained mixed-bred Arabian horses performed a single-step riding test on a wet (compacted sand) or dry (uncompacted sand) racetrack surface. The wet racetrack received a daily wetting and was compacted using a tractor, while the dry racetrack was upturned by a tractor daily. Both racetracks were elliptical with straight lines of 600 m and total length around 900 metres. Blood samples were drawn from the jugular vein, immediately after the end of the test, and used for the analysis of blood lactate concentration. Mean blood lactate concentration was significantly higher after the riding test on the dry racetrack (2.6 ± 1.6 mmol/L) compared with wet racetrack (0.9 ± 0.3 mmol/L) surface (p = 0.007; d = 1.48, [large]; 95%CI = 0.37–2.44). In conclusion, dry racetrack surface increases lactic anaerobic contribution in trained Arabian horses during a single-step riding test in the field.

Gastrointestinal stromal tumor resulting in recurrent colic in a arabian horse gelding a report of case

Background: A Grey 12-year-old Arabian endurance horse gelding was referred to the SHS Veterinary Center for anorexia, mild colic of 5 days duration, and melena of 1 day duration. The owner reported recurring colic, 12 episodes of mild colic in the previous year. Methods: On admission, vital signs were within normal limits and body condition score was estimated to be 3/9. Results: Packed cell volume (PCV) was 28% [reference range (RR): 31% to 47%] and plasma total protein was 58 g/L (RR: 60 to 80 g/L). Hematochezia was observed. Abdominal ultrasound examination detected no abnormalities. Over the next 12 h, the horse experienced hematochezia and several mild episodes of colic and death. A necropsy was performed. A mass arising from the right dorsal ascending colon near the base of the cecum and extending transmurally from the colonic mucosa into the mesocolon was a 8 cm × 5 cm × 8 cm firm, homogenous, tan mass. The portion of the mass that extended into the colonic lumen was pedunculated, with an ulcerated surface. The adjacent segments of colon were markedly reddened and edematous. Histologically, the mass was comprised of large interweaving sheets of small, spindle cells with ill-defined cell borders embedded in abundant myxomatous matrix. Tumor cells contained scant eosinophilic cytoplasm and oval to elongate nuclei with finely stippled chromatin and inconspicuous nucleoli. Mitotic figures were rare (1/10) high power fields. Tumor infiltrated between the muscularis interna and the muscularis externa at the myenteric plexi. Conclusion: Gross and histologic appearance, were consistent with a diagnosis of gastrointestinal stromal tumor.

Plantar fasciitis in 19 endurance horses: Diagnosis, treatment and follow‐up

SummaryLesions of the peritendinous–periligamentous soft tissues of the tarsus (plantar fasciitis) commonly result in a curb‐like appearance and are considered overrepresented in Standardbred racehorses; however, plantar fasciitis is also quite common in endurance horses. Nineteen endurance horses of different ages (median: 7 years; range: 3–13) and athletic activity level comprising a total number of 25 plantar fasciitis cases were described in this study. In nine cases, injury developed during a training session, and in 16 cases, it developed during competition. In 18 cases, there was swelling, heat and pain on palpation, and in six cases, only swelling was detected. Eight cases were not lame at the time of examination, while in 17 cases, lameness ranged from grades 1–3 on the American Association of Equine Practitioners modified grading scale. The degree of swelling was significantly related to the lameness grade. Ultrasonography revealed differing amounts of thickening of the plantar fascia plantar to the superficial digital flexor tendon and peritendinous–periligamentous oedema of heterogeneous appearance. Horses were treated conservatively with several combinations of rest, controlled exercise, ice‐therapy, corticosteroids, local application of working counterirritants and therapeutic shoeing. Seventeen of 25 cases (68%) did not develop re‐injury after treatment and rehabilitation, whilst eight of 25 (32%) developed one or more re‐injury/injuries. Overall, 21 of 25 cases (84%) returned to the previous or a higher level of competition; in one case (4%), the injury was the cause of retirement from athletic activity. Plantar fasciitis can be considered a sport‐related injury in endurance horses of all ages and athletic activity level. Re‐injury rate is low; however, adequate rest and rehabilitation protocols are important. Plantar fasciitis rarely leads to retirement from athletic activity, but it can result in 2–5 months out of training and competition.

Glutamine supplementation affects Th1 and Th2 cell populations in endurance horses

This study was set out to test the effect of glutamine supplementation on Th1 and Th2 cell populations in endurance horses. The sample was comprised 33 horses competing in four FEI races and successfully completing the final vet check. Horses competed in different distance categories, as follows: 80 km (13 horses, 6 supplemented and 3 controls), 120 km (14 horses; 9 supplemented and 5 controls) and 160 km (6 horses; 3 supplemented and 7 controls). Supplementation consisted of 60 mg/kg bodyweight of oral L-glutamine given for 30 days prior to and 15 days after the race. Blood samples were collected into vacuum tubes with and without EDTA at the following time points: short before race start time, prior to tack fitting (T0); right after and within 3 h of the final vet check (T1 and T2 respectively). Further blood samples were collected at the farm of origin 3, 7 and 14 days after the race (T3, T4 and T5 respectively). Glutamine supplementation affected T-lymphocyte population balance, as shown by increased CD4+/CD8+ ratio, and increased Th1 and Th2 cytokine production. Glutamine also modulated post-exercise cortisol increased in supplemented horses in this sample. These findings suggest glutamine supplementation attenuates exercise-induced immunosuppression.

Combining Threshold, Thurstonian and Classical Linear Models in Horse Genetic Evaluations for Endurance Competitions.

Simple SummaryEndurance competitions are carried out across the countryside worldwide, where the adapted physical and metabolic conditions of the horses are essential to satisfactorily end the competition. Horse breeding programs usually use the rank and time to improve the performance of horses in competitions. It is also relevant to analyse the placing trait i.e., whether or not a horse finishes the race. The discontinuous nature of rank and placing traits require special methodologies to deal with them. Here we have used 6135 endurance records from 1419 horses, with a pedigree containing 10,868 animals, to develop a multitrait model with a new free software tool (GIBBSTHUR). The obtained results suggest that it is possible to ignore the race time and use rank and placing to perform the genetic evaluation in endurance horse populations.The racing time and rank at finish traits are commonly used for endurance horse breeding programs as a measure of their performance. Even so, given the nature of endurance competitions, many horses do not finish the race. However, the exclusion of non placed horses from the dataset could have an influence on the prediction of individual breeding values. The objective of the present paper was to develop a multitrait model including race time (T), rank (R) and placing (P), with different methodologies, to improve the genetic evaluation in endurance competitions in Spain. The database contained 6135 records from 1419 horses, with 35% of the records not placed. Horse pedigree included 10868 animals, with 52% Arab Horses. All models included gender, age and race effect as systematic effects and combined different random effects beside the animal and residual effects: rider, permanent environmental effect, and interaction horse-rider. The kilometers per race was included as a covariate for T. Heritabilities were estimated as moderately low, ranging from 0.06 to 0.14 for T, 0.09 to 0.15 for P, and 0.07 to 0.17 for R, depending on the model. T and R appeared mostly as inverse measures of the same trait due to their high genetic correlation, suggesting that T can be ignored in future genetic evaluations. P was the most independent trait from the genetic correlations. The possibility of simultaneously processing the threshold, Thurstonian and continuous traits has opened new opportunities for genetic evaluation in horse populations, and much more practical genetic evaluations can be done to help a proper genetic selection.

A Descriptive Study of Training Methods for Fédération Equestre Internationale Endurance Horses in New Zealand

Training measures, particularly those that examine the interactions between training volume, speed, and recovery, can improve understanding of training practices that contribute to success and avoid adverse horse welfare outcomes in endurance competitions. This study describes the training of Fédération Equestre Internationale (FEI) 100–160 km level horses in New Zealand. A convenience sample of 16 participants and 25 horses were surveyed before commencement of training. Participants then reported daily data for an entire nine-month season of training and competition. Participants began their season with predetermined goals and individual training plans for each horse. They intended to use competitions for training. Competitions contributed a median of 44% [IQR, 36%–49%] of total accumulated distance (in training and competition) for each horse for the season, despite being only 11% (207/1,933) of all days worked. Most starts (80%) were in domestic-level (CEN) competition ≤80 km. Speed ranged from 2–18 km/hour on home training days to 6–18.5 km/hour in CEN competitions and 10.9–16.9 km/hour in FEI competitions. Horses were worked 34% [IQR, 21–38] of days in training, ranging from 12% to 55% for individual horses. The most common horse health problem was lameness, affecting 12/25 horses, for a median of 9 (range, 1–78) days. This study highlights the potential for CEN data as a resource to improve understanding of training and competition load, speed, and recovery and therefore reduce adverse horse welfare outcomes in FEI competitions.

Hold your horses! A typology of endurance horse-riding participants

ABSTRACT Rationale: Limited research is available on endurance horse riding participants. Purpose: This research identified different segments of these niche participants. Methods: Self-administered questionnaires were distributed to participants during an international endurance ride held in South Africa. Based on convenience sampling, a total of 116 completed questionnaires were obtained. Five motives to participate in the race (race, challenge, intrinsic, equine performance and event experience achievement) and four behavioural involvement pursuits (passive equine pursuits, event loyalty pursuits, active equine pursuits, and health and fitness pursuits) were identified. Based on these factors, three distinct endurance horse riding participant segments were identified: Equine achievers, Equine pursuers, and Equine challengers. Findings: The findings confirm that endurance sport participants cannot be regarded as homogenous. Contributions: Endurance horse riding events can be seen as a means to facilitate and encourage additional behavioural involvement pursuits that help expand the endurance horse-riding industry in South Africa.

Do waiting times in endurance vet gates affect the cardiac recovery index?

The cardiac recovery index (CRI) is currently a key component of veterinary inspections to assess endurance horses metabolic status and fitness. Originally published by Ridgeway, it instructs veterinarians to subtract from the first heart rate (HR1), collected when the horse is initially presented for examination, a second HR (HR2), taken 1 min after the horse starts a 125 feet (38.1 m) out and back trot to assess gait. It is widely believed that an increase of more than 4 bpm from HR1 might be an indicator of fatigue. The FEI rules instruct the veterinarians to start the stopwatch exactly 1 min after the HR1 count instead of trot start, as described previously. The aims of this study were to investigate how time delays in the vet gate affect the HR1 count and the CRI during endurance competitions, and to characterise and compare the time taken by veterinarians to measure the original version of the CRI (tCRIRIDG) and the adapted CRI used in FEI endurance events (tCRIFEI). Data from 972 veterinary inspections of horses that took place in different endurance competitions in three different venues were collected. There was no association between the time elapsed from entering the vet gate to the start of the HR1 count or from the HR1 count to the start of the trot-up and the HR1 or the CRI (P&gt;0.05). However, larger studies involving more venues and different layouts are needed to corroborate our findings and to characterise the sensitivity and specificity of the CRI regarding the baseline heart rate. Although this study did not show an influence of waiting times on the CRI, a reduced deviation from the mean observed across all veterinarians when using the original Ridgeway guidelines to calculate the CRI (tCRIRIDG) seems to point a better time-wise consistency when this version is used.

Relative aerobic and anaerobic energy contribution in race fit endurance and Thoroughbred racehorses during strenuous exercise

The objective was to compare fit Arabian endurance and Thoroughbred racehorses’ responses to a maximal intensity standardised incremental treadmill test (MaxSIT) with respect to: (1) their relative aerobic contributions during maximal exercise; and (2) selected physiological parameters related to performance. Six high-level endurance Arabians and six race-ready Thoroughbreds performed a MaxSIT starting at 8 m/s and increasing by 1 m/s increments 60 s until maximum oxygen consumption (V̇O2max) was reached. Heart rate (HR), blood lactate concentration (BLac), haematocrit (Hct), minute ventilation (V̇E) and oxygen consumption (V̇O2) were measured. V̇O2max, the speeds at which the HR were 200 and 160 bpm, respectively (V200, V160), the speed at which the BLac reached 4 mmol/l (VLa4) and lactate at HR200(BLa200) were calculated. The relative aerobic energy input was determined using ΔBLacPeak-Restingincrease as previously described. Data were expressed as median with interquartile range and analysed with a Wilcoxon rank sum test (P&lt;0.05). Endurance horses had greater V̇O2max(202.5 ml/(kg.min) (190.3-211) vs 152.7 ml/(kg.min) (140.5-158.3);P&lt;0.001) and had a greater aerobic energy contribution to total exercise effort (89.9% (87.0-96) vs 82.8% (81.1-84.1);P=0.009) than Thoroughbreds. Endurance horses reached HR&gt;200 bpm on the treadmill, but had a lower HRmax(210 bpm (205-217) vs 226 bpm (219-228);P=0.008), BLa200(3.8 mmol/l (2.7-5.5) vs 4.8 mmol/l (3.6-5.2);P&lt;0.001) and Hctmax(56.4% (54.9-57.5) vs 61.5% (59-64);P=0.002). Endurance horses median VLa4 was 11.6 m/s (11.0-13.0); V200=11.9 m/s (10.9-12.3) and V160=8.5 m/s (7.2-8.6). Because of the HR and speed characteristics of modern endurance races, we proposed BLa200as a new calculated parameter with which to assess endurance horses. Trained endurance horses accumulate less lactate, have a greater V̇O2maxand relative aerobic contribution to their energy requirements at maximal intensity exercise despite a lower blood haematocrit.