Preliminary Examination of the Biological and Industry Constraints on the Structure and Pattern of Thoroughbred Racing in New Zealand over Thirteen Seasons: 2005/06–2017/18

This study aimed to examine thirteen seasons of flat racing starts (n = 388,964) in the context of an ecological system and identify metrics that describe the inherent characteristics and constraints of the New Zealand Thoroughbred racing industry. During the thirteen years examined, there was a 2–3% per year reduction in the number of races, starts and number of horses. There was a significant shift in the racing population with a greater number of fillies (aged 2–4 years) having a race start, and subsequent longer racing careers due to the inclusion of one more racing preparation post 2008 (p < 0.05). Additionally, there was an increasingly ageing population of racehorses. These changes resulted in more race starts in a career, but possibly because of biological constraints, there was no change in the number of race starts per season, starts per preparation, or days spelling between preparations (p < 0.05). There was no change in the proportion of horses having just one race start (14% of new entrants), indicating that the screening for suitability for a racing career remained consistent. These data identify key industry parameters which provide a basis for future modelling of intervention strategies to improve economic performance and reduce horse injury. Consideration of the racing industry as a bio-economic or ecological model provides framework to test how the industry may respond to intervention strategies and signal where changes in system dynamics may alter existing risk factors for injury.

Occurrence and Genetic Diversity of Babesia caballi and Theileria equi in Chilean Thoroughbred Racing Horses

This study aimed to serologically and molecularly survey Babesia caballi and Theileria equi in thoroughbred horses from racecourses in Chile. Additionally, the genetic diversity of the positive samples was assessed. A total of 286 thoroughbred horses from the Santiago and Valparaíso racecourses had their serum samples submitted to an ELISA for B. caballi and T. equi, and 457 samples (from the Santiago, Valparaíso, and Concepción racecourses) were tested with nested PCRs for the B. caballi 48 KDa rhoptry protein (RAP-1) and T. equi 18S rRNA genes. Selected RAP-1 and 18S positive products were sequenced to perform phylogenetic and haplotype analyses. An overall seroprevalence of 35.6% was observed for these Chilean racecourses: 23.7% for T. equi, 8.4% for B. caballi, and 3.5% for both agents. Overall, a 53.6% occurrence by nPCR was detected for the three Chilean racecourses: 44.2% for T. equi, 5.4% for B. caballi, and 3.9% for both agents. Phylogenetic analysis of T. equi and B. caballi showed genetic proximity with sequences previously detected in other countries. Haplotype analysis revealed a low diversity among the Chilean sequences, which may have originated from those reported in Brazil, Israel, or Cuba. Babesia caballi and T. equi were detected for the first time in Chilean thoroughbred horses.

Introduction

On October 20, 1923, at Belmont Park in New York, Kentucky Derby champion Zev toed the starting line alongside Epsom Derby winner Papyrus, England's top three-year-old colt. Few happenings had ever been covered so closely by American newspapers as the spectacle officially dubbed the International Race. The extraordinary hype surrounding the event was even more notable considering that only a few years earlier Thoroughbred racing had been on the brink of Progressive-era extinction in the United States. But following a post-World War I political sea change in the United States, in what would later be remembered as a "golden age" of sport, Americans rallied around the horse that was, in the words of its owner Harry F. Sinclair, "racing for America," while Sinclair was engaged in a scheme to defraud the United States of millions of barrels of publicly owned oil in one of the most notorious instances of political corruption in American history -- the Teapot Dome scandal. America First examines the postwar revival of American horseracing, culminating in the intercontinental showdown between Zev and Papyrus, that captured some of the incongruity and contradiction of 1920s America.

Return of Thoroughbred Racing Horses to the Races after Treating Slab Fractures of the Third Carpal Bone with PRP and Stem Cells

Background: Despite the fact that slab fracture of the third carpal bone is an event of great worldwide relevance in racehorses, the third carpal fracture doesn’t have data on treatments and return to racing in Brazil. The search for efficient treatments and which provide recovery providing horses return to racing is an objective of sports equine medicine. Regenerative therapies like Platelet Rich Plasma (PRP) and Stem Cells (MSc) have demonstrated a great potential in the treatment of several injuries. For the treatment of three Thoroughbred racing horses at Brazilian Jockey Club, with sagittal plane slab fractures of the third carpal bone, we used the association of PRP and Stem Cells for reduction of the rest and good return to conditions athletics of these horses.Cases: Three Thoroughbred racing horses, males, 4 and 5 years old, showed slab fracture third carpal bone in different moments of their activity at Brazilian Jockey Club. Usually, the treatment for this type of fracture is the arthroscopic repair and the conservative management. We performed after initial radiographic evaluation dorsoproximal-dorsodistal oblique (DPr-DDiO) “skyline”, intra-articular applications of PRP and MSCs. The treatments were performed according to the radiographic follow-up of the lesion evolution. No other treatment was performed concomitantly with cell therapy in the 3 treated patients. Three treatments were performed in the first patient and 2 in the second and third patients. Before each treatment for all patients, we performed radiography dorsoproximal-dorsodistal oblique (DPr-DDiO) ‘skyline’ of the carpus. After this step, the animal was sedated with 10% xylazine hydrochloride at a dose of 0.5 mg/kg intravenously. Antisepsis of the carpus was performed and applied with radiographic monitoring of the needle positioning, first the PRP in the volume of 2 mL and in sequence, 20 million cells MSCs suspended in autologous plasma from the cell bank of the Cellen veterinary stem cell laboratory, totalizing 4 mL. The 3 horses returned to their training routines and continued to be monitored by clinical examinations and radiography, there were no post-treatment complications and all ran again in the median time of 253 days after the first application of PRP and stem cells. Everyone won the first race after treatment.Discussion: The 3 patients suffered the fractures after running at the Brazilian Jockey Club. All fractures were simple- no comminuted slab fractures of the third carpal. In our study, we chose to carry out the treatments with PRP and MSCs by intra-articular application. The regenerative medicine occupies a prominent place in recovery from injuries and the association of PRP and MSCs have played an important role in the treatment of athlete horses in tendons, bones and joint injuries and our work, the treatment was effective, without complications, helped to reduce local inflammation, perceptually reducing the pain observed before the application and the animals started running again with a quality equivalent to that observed before the occurrence of injuries. This way, our results demonstrated that the association PRP and MSCs was effective in recovering the 3 patients, all of them ran after injury. The median time for racing was 253 days and the horses won their first races after fractures occurred. These results encourage the use of the association of PRP and MSCs also for no comminuted sagittal plane slab fractures of the third carpal in Thoroughbred Racing horses.

Effects of Racing Surface and Turn Radius on Fatal Limb Fractures in Thoroughbred Racehorses

North American Thoroughbred racing is conducted on three types of surfaces—dirt, turf, and synthetic. The tracks are oval, and races are run counterclockwise. The loading on right and left limbs is expected to differ as a function of turn radius, banking, surface, and gait asymmetry. Hind limbs and forelimbs also have different functions related to propulsion and turning, respectively. This study uses the Equine Injury Database for race starts from 1 January 2009 through 31 December 2014, to compare injury rates across participating North American racetracks. The data are limited to catastrophic injuries in which horses died or were euthanized due to a fracture within 72 h of the start of the race. Overall injury rates were lower on turf and synthetic surfaces and the pattern of limb injuries in left vs. right and fore vs. hind limbs were different. Regardless of surface, forelimbs were more likely to fracture. Dirt surfaces showed higher rates of forelimb injuries compared to other surfaces, hind limbs were more likely to experience a fatal fracture on turf than on dirt. The left fore and right hind limbs were more likely to experience a fatal fracture but only on dirt surfaces.

Injuries among Maryland jockeys during thoroughbred racing: 2015–2019

ObjectivesOur goal was to characterise jockey injuries at Maryland racetracks during thoroughbred racing activities over 4 years using medical records maintained by the sports medicine team.MethodsInjury data were prospectively gathered by sports medicine physicians who were onsite for all thoroughbred racing activities in Maryland from 12 September 2015 to 5 May 2019 to evaluate and treat any injury to the jockeys. Descriptive statistics (frequencies, rates with corresponding 95% CIs and proportions) of injury types, body parts, mechanisms, severity and location on track were calculated.ResultsOver nearly 4 years of racing and 45 000 mounts, there were 204 injuries involving 184 incidents and 131 falls during those races. The vast majority of injuries (80%) was related to soft tissue, while 4% were concussions. Most injuries involved the lower extremity (31%) or upper extremity (26%) and typically resulted from a fall from the horse. Among all incidents, 79.3% (n=146) resulted in an injury, while 76.3% (n=100) of falls resulted in an injury. We identified a significant proportion of injuries (41%) in and around the starting gate. Over a quarter of incidents resulting in injury required further medical care in hospital or other medical facility, while surgery was required in 2.5% of injuries.ConclusionAccess to a consistent group of sports medicine providers facilitated jockey injury reporting and tracking. The majority of jockey injuries is related to soft tissue and results from falls, while the starting gate area is associated with the greatest proportion of injuries.

378 Making-Do When Big Data Isn’t Big Enough: Limitations and pathways of possible development in the prediction of Thoroughbred racing performance as a breeding outcome

A performance genetics model adapted to real-world data of Thoroughbred racing and breeding will be presented. The continuity of ancestry and performance is documented in the annals of pedigree, not as functional counterparts, but as corresponding signs of market value. Pedigree invites chronic misprision of highly diverse genetic resources competing for scarce opportunity in the racing economy, resulting in samples that are often small and of dubious composition. Data is specialized for competing “pedigree analysis” that packages the system of signification to meet market demand for meaning. Given statistical deficits, this data is a necessary inferential asset of the model. The model’s premise is that predictability is optimized if racing performance is defined as the function of an indivisible relation between parents. Statistical data consists of 6-generation ancestries of mares that produced offspring by a subject stallion. Comparison of proportions is used to identify effects resulting from his relation to individual ancestors of the subject mare. Expected performance by the sire’s offspring is defined as the proportion of mares that produced a superior runner by him. Each ancestor of a subject mare also has descendants among the mares that produced offspring by the stallion. For each of those groups, the proportion of mares that produced a superior runner is compared with the stallion’s expected performance using a t-test of statistical significance at the .10 level. Probable effect is further tested by case study involving such variables as racing class, generational distance, sex-linkage, inbreeding, and an ancestor’s pattern of effect across the stallion population. Stallions with the highest prevalence of positive effects are preferred for the subject mare. This model, under the trade name LyonScore®, has been used since 2012 by Werk Thoroughbred Constultants, Inc. as a component of its client services. Table 1: The data, listed in tabular format below, is graphically displayed for actual use on an ancestry tree whose nodes are numbered by relation to a subject mare (“Position”). Each statistical data item in the table is derived from the stud record of a stallion named Distorted Humor and corresponds with an ancestor of a mare named Positively Royal. Each ancestor of this mare is also an ancestor of a group of mares that produced offspring of Distorted Humor and were at least three years of age as of 2019. A proportion of each of those groups of mares produced at least one superior runner. Proportions that differ significantly from Distorted Humor’s expected proportion are so indicated. Only ancestors involving a group of at least 18 mares are considered to have inferential value on statistical grounds. Table 2: The sire Danzig is an ancestor of Positively Royal, along with 75 mares that produced foals by Distorted Humor, only five of which produced a superior runner by him, significantly fewer than expected. However, since Distorted Humor’s dam is by Danzig, the question of generational distance is relevant as a variable to the effect of inbreeding. The table below shows Danzig’s proportional distribution by genetic relation to those 75 mares as indicated by “Position.” Of the 64 mares in descent of Danzig within three generations, three mares produced a superior runner. It’s notable, though, that 2 of 6 mares with the same relation to Danzig as Positively Royal produced superior runners. Since Danzig is the only ancestor with a negative effect, further consideration is warranted. Table 3: In a population that tends to slough off unprofitable genetic resources, overspecialization is the main risk of close inbreeding. Some generational variations of an ancestor’s contribution can turn inbreeding to less specialized effect, but this depends on generational distance. Distorted Humor’s earliest opportunity with mares in descent of Danzig involved offspring closely inbred to Danzig, but later in his career he encountered mares for which variation was more likely. As the table shows, two of six mares descending from Danzig in position 25 (4th generation) produced Distorted Humor’s best runners inbred to Danzig, so it is of some interest that Positively Royal, the subject mare, is also a postion-25 descendant of Danzig. However, that those two mares happen to be full sisters whose breeding has little else in common with that of Positively Royal leaves the question of Distorted Humor’s fitness for this mare less certain than would be preferred.

Is Whip Use Important to Thoroughbred Racing Integrity? What Stewards’ Reports Reveal about Fairness to Punters, Jockeys and Horses

The idea that whip use is critical to thoroughbred racing integrity is culturally entrenched but lacks empirical support. To test the longstanding beliefs that whip use aids steering, reduces interference, increases safety and improves finishing times, we conducted a mixed-method analysis of 126 race reports produced by official stewards of the British Horseracing Authority, representing 1178 jockeys and their horses. We compared reports from 67 “Hands and Heels” races, where whips are held but not used (whipping-free, WF), with 59 reports from case-matched races where whipping was permitted (whipping permitted, WP). Qualitative coding was used to identify and categorise units of analysis for statistical testing via logistic regression and linear mixed model regression. For both types of race, we explored stewards having anything to report at all, movement on course, interference on course, incidents related to jockey behaviour and finishing times. There were no statistically significant differences between WF and WP races for anything to report (OR: 3.06; CI: 0.74–14.73), movement on course (OR: 0.90; CI: 0.37–2.17), interference (OR: 0.90; CI: 0.37–2.17), jockey-related incidents (OR: 1.24; CI: 0.32–5.07), and race times (0.512 s, t = 1.459, p = 0.150). That is, we found no evidence that whip use improves steering, reduces interference, increases safety or improves finishing times. These findings suggest that the WF races do not compromise racing integrity. They also highlight the need for more effective ways to improve the steering of horses.

Seroprevalence of Leptospira in Racehorses and Broodmares in New Zealand

A cross-sectional survey was conducted to determine the seroprevalence of Leptospira in a cohort of horses and to evaluate potential risk factors for Leptospira seropositivity in horses in New Zealand. The convenience sample included 499 Thoroughbred racing and breeding horses from 25 commercial properties in North Island, New Zealand. A questionnaire was used to collect demographic data on horses and property-level information on grazing and management practices, pest (rodent) management, access to natural waterways, other livestock on the property, and possible contact with wildlife. The microscopic agglutination test was used to test sera for serovars Ballum, Copenhageni, Hardjo (bovis), Pomona, and Tarassovi. Logistic regression was used to investigate the risk factors for Leptospira seropositivity to at least one serovar and for each serovar individually. A total of 124 (25%, 95% confidence interval (CI) 21–29%) horses had positive titres to any one of the five serovars. The seroprevalence of Ballum, Copenhageni, Hardjo (bovis), Pomona, and Tarassovi was 5% (95% CI 3–7%), 9% (95% CI 7–12%), 6% (95% CI 4–8%), 6% (95% CI 4–8%), and 6% (95% CI 4–8%), respectively. Broodmares, compared to racehorses and alternately grazing horses with sheep, increased the odds of exposure to any one serovar, whilst grazing the same time as sheep and alternately grazing horses with cattle increased the odds of exposure to Ballum and Hardjo (bovis), respectively. Historical exposure to Leptospira in racing and breeding horses was identified, and risk factors were consistent with pasture-based exposure.