• Asian-Australasian Journal of Animal Sciences
• /
• v.28 no.6
• /
• pp.771-781
• /
• 2015

Thoroughbred, a relatively recent horse breed, is best known for its use in horse racing. Although myostatin (MSTN) variants have been reported to be highly associated with horse racing performance, the trait is more likely to be polygenic in nature. The purpose of this study was to identify genetic variants strongly associated with racing performance by using estimated breeding value (EBV) for race time as a phenotype. We conducted a two-stage genome-wide association study to search for genetic variants associated with the EBV. In the first stage of genome-wide association study, a relatively large number of markers (~54,000 single-nucleotide polymorphisms, SNPs) were evaluated in a small number of samples (240 horses). In the second stage, a relatively small number of markers identified to have large effects (170 SNPs) were evaluated in a much larger number of samples (1,156 horses). We also validated the SNPs related to MSTN known to have large effects on racing performance and found significant associations in the stage two analysis, but not in stage one. We identified 28 significant SNPs related to 17 genes. Among these, six genes have a function related to myogenesis and five genes are involved in muscle maintenance. To our knowledge, these genes are newly reported for the genetic association with racing performance of Thoroughbreds. It complements a recent horse genome-wide association studies of racing performance that identified other SNPs and genes as the most significant variants. These results will help to expand our knowledge of the polygenic nature of racing performance in Thoroughbreds.

• Journal of Animal Science and Technology
• /
• v.53 no.1
• /
• pp.23-27
• /
• 2011

This study was conducted to provide basic information for the improvement of racing performance of Jeju pony & Halla horse, using the 85,732 racing records collected from Jeju & Kwacheon racecourses from January 1, 2005 to December 31, 2009. During the last 5 years, a total of 2,892 heads of horses were racing at the Jeju racecourse and 11.7% (338 heads) of them were Jeju ponies. The average body weight of Jeju pony and Halla horse were 267 kg & 287 kg, respectively, which were 58% and 62% of that of Thoroughbred (460 kg). The repeatabilities of Jeju pony, Halla horse and Thoroughbred for finishing time were estimated in the range of 0.26-0.66 (average, 0.54), 0.34-0.68 (average, 0.56) and 0.37-0.60 (average, 0.50), respectively, and as the racing distance increased, the repeatabilities decreased. In the racing distance of 1,000 m, the differences in the finishing times between Thoroughbred & Jeju pony, Thoroughbred & Halla horse, and Jeju pony & Halla horse were 24.33 seconds, 10.81 seconds and 13.52 seconds, respectively. The racing performance of Halla horse was improved by 55.6% than that of Jeju pony at the 1,000 m race.

• Journal of Veterinary Clinics
• /
• v.39 no.6
• /
• pp.405-410
• /
• 2022

An 11-year-old thoroughbred post-partum broodmare presented with the symptoms of colic. The physical and clinical examinations indicated a large colon displacement or volvulus. Immediate surgical intervention was performed, and a strangulating large colon volvulus (LCV) was defined as a volvulus of >540° in the counterclockwise direction. After correcting and assessing the gut viability, approximately 80% of the entire large colon was resected and anastomosed using an end-to-end technique. With supportive care after surgery, the horse regained its appetite and vitality without significant clinical complications and was discharged on postoperative day 9. This report presents the first surgical correction using a large colon resection and anastomosis (LCRA) and the critical care for a strangulating LCV in a horse in Korea. This case enhances the current knowledge of clinical LCV and the related considerations for treatment.

• Safety and Health at Work
• /
• v.10 no.3
• /
• pp.384-388
• /
• 2019

The horse stable hand workers are one of the most important occupations in horse-racing industry. However, suicide problem of the horse stable hand workers in Korea has raised the necessity of new study on how these workers experience mental health problems such as occupational stress and depression in organizational situation. Therefore, this study investigated the occupational stress and depression level of the horse stable hand workers and identified the structural relationship in the horse-racing industry through a detailed interview. A total of 207 horse stable hand workers participated in this study, and occupational stress and depression level were surveyed using the Korean Occupational Stress Scale (KOSS) and Korean version of the Center for Epidemiologic Studies-Depression Scale (CES-D). The results of this study showed that the occupational stress level of horse stable hand workers was higher than the median of Korean population. The significant difference in occupational stress among the detail job grade was also identified. In addition, 34% of the horse stable hand workers showed high risk of depression, and job demand, organizational system, and inappropriate compensation as the subfactors of occupational stress were showed to mainly affect depression. Although there are some limitations according to the field survey, this study also has significant meaning in that it identifies the relationship between the occupational characteristics of the horse stable hand workers and the mental health. It will be necessary to study the diverse organizational situation and individual mental health for new occupations.

• Asian-Australasian Journal of Animal Sciences
• /
• v.19 no.6
• /
• pp.784-788
• /
• 2006

Microsatellite polymorphism and the genetic relationship were estimated using genotype information of 305 horses from 11 microsatellite loci. The breeds include the indigenous Korean breeds, Korean native horse (102) and Jeju racing horse (56) together with Japan Hokkaido horse (5), Mongolian horse (19), Thoroughbred horse (108), Quarter horse (11) and Przewalskii horse (4). Allelic frequencies, the number of alleles per locus were estimated by direct counting from observed genotype, and genetic variability was computed using the CERVUX software and DISPAN. The number of alleles per locus varied from 6 (HMS6) to 18 (ASB17) with an average value of 10.45 in horse breeds. The expected total heterozygosity ($H_T$) and coefficient of gene differentiation ($G_{ST}$) ranged 0.764-0.921 (the average value was 0.830) and 0.102-0.266 (the average value was 0.180) in horse breeds, respectively. Four populations (Przewalskii horse, Japan Hokkaido horse, Quarter horse, Thoroughbred horse) showed lower heterozygosity than the average value (the average value was 0.710). The expected heterozygosity within breed ($H_S$) and mean no. of observed alleles ranged from $0.636{\pm}0.064$ (Japan Hokkaido horse) to $0.809{\pm}0.019$ (Mongolian horse), and from 2.73 (Przewalskii horse) to 8.27 (Korean native horse), respectively. The polymorphic information content (PIC) ranged from 0.490 (Przewalskii horse) to 0.761 (Mongolian horse) with an average value of 0.637 in horse breeds. The results showed three distinct clusters with high bootstrap support: the Korean native horse cluster (Korean native horse, Mongolian horse), the European cluster (Przewalskii horse, Thoroughbred horse), and other horse cluster (Jeju racing horse, Japan Hokkaido horse, and Quarter horse). A relatively high bootstrap value was observed for the Korean native horse cluster and European cluster (87%), and the Korean native horse and Mongolian horse (82%). Microsatellite polymorphism data were shown to be useful for estimating the genetic relationship between Korean native horse and other horse breeds, and also be applied for parentage testing in those horse breeds.

• Journal of Veterinary Clinics
• /
• v.37 no.4
• /
• pp.217-222
• /
• 2020

A 3-year-old male Thoroughbred serving as a Korean racehorse named RAON PORTEOUS presented with acute lameness concomitant with edema and fever in the right carpal joint after completing a horse race. Through radiological examination using lateromedial oblique, flexed lateromedial oblique and dorsopromixal-dorsodistal oblique views, the horse was diagnosed with a slab fracture in the 3^rd carpal bone of right forelimb. The fracture was surgically approached and corrected by applying 4.5 mm leg screw fixation during surgery. At eight months post-surgery, the horse was able to return to racing and has had successful racing performances with two wins and several prizes in the last 8 months. This is the first reported case of the successful use of lag screw fixation surgery in Korea with the horse showing complete recovery from a severe injury that is often considered fatal in a racehorse.

• Journal of Veterinary Science
• /
• v.24 no.6
• /
• pp.81.1-81.12
• /
• 2023

Background: The incidence of colic and the outcomes of colic surgery have not been surveyed in racetracks in Korea. Objectives: This study examined the incidence, mortality, and case fatality of colic and investigated the effects of age and sex after an exploratory celiotomy on the long-term survival rate (return to racing), subsequent racing performance, and career longevity. Methods: The incidence, mortality, and case fatalities of colic were examined over an 11-year period. The records of 40 horses that had undergone a celiotomy, after participating in at least one race and 75 race-matched control horses were analyzed. The racing performance and career length of the horses that returned to racing post-surgery were compared with a control group. Results: The annual incidence, fatality rate of colic, and annual mortality rate at Seoul Racecourse were 6.5, 2.8 per 100 horse-years, and 0.2 deaths cases per 100 horse-years, respectively. Of the 40 horses that underwent colic surgery, 26 (65%) returned to racing. The likelihood of returning to racing decreased with increasing age of the horses, and geldings had a lower probability of returning. While the performance in the five preoperative races between the two groups was not significantly different, a significant decrease in racing performance was observed after the surgery date (p < 0.01). Horses that underwent colic surgery did not show a significant decrease in career length. Conclusions: Surgical treatment for colic at the age of three and four years had a negative impact on the racing performance. On the other hand, there was no significant difference in career longevity between the two groups.

• Proceedings of the Korean Society of Veterinary Clinics Conference
• /
• 2006.05a
• /
• pp.110-110
• /
• 2006

• Asian-Australasian Journal of Animal Sciences
• /
• v.31 no.3
• /
• pp.309-315
• /
• 2018

Objective: This study aimed to test the expression patterns of ERBB receptor feedback inhibitor 1 (ERRFI1) before and after exercise and the association of non-synonymous single-nucleotide polymorphisms (nsSNPs) of horse ERRFI1 with racing traits in Thoroughbreds. Methods: We performed bioinformatics and gene expression analyses for horse ERRFI1. Transcription factor (TF) binding sites in the 5'-regulatory region of this gene were identified through a tool for prediction of TF-binding site (PROMO). A general linear model was used to detect the association between the nsSNP (LOC42830758 A to G) and race performance. Results: Quantitative polymerase chain reaction analysis showed that expression level of ERRFI1 after exercise was 1.6 times higher than that before exercise. Ten transcription factors were predicted from the ERRFI1 regulatory region. A novel nsSNP (LOC42830758 A to G) was found in ERRFI1, which was associated with three racing traits including average prize money, average racing index, and 3-year-old starts percentile ranking. Conclusion: Our analysis will be helpful as a basis for studying genes and SNPs that affect race performance in racehorses.

• Korean Journal of Veterinary Research
• /
• v.45 no.1
• /
• pp.127-130
• /
• 2005

The objective of present study was to ascertain sex determination for individual identification, parentage control, and sex chromosome anomalies in horse. PCR amplification products of the equine sex determining region of the Y chromosome gene (SRY) and amelogenin gene (AMEL) were detected by using agarose gel electrophoresis. A normal sire and foal II showed 1 SRY band (430 bp) and 3 AMEL (AMELX, AMELY, and AMELX/Y) band, 175 bp, 160 bp, 190 bp, respectively, and a normal dam and foal I showed a single AMELX band (175 bp). These results enables a quick diagnosis for sex determination prior to cytogenetic analysis.