• Journal of Life Science
• /
• v.31 no.12
• /
• pp.1088-1093
• /
• 2021

Jeju horse (Equus ferus caballus) is a Korean horse breed that has been native to Jeju Island for a long time. Jeju horses are used as racehorses, and their racing ability is a major economic trait. The role of the myostatin (MSTN) gene in skeletal muscle mass has been studied in various mammals, and mutations in the MSTN gene are known to affect the racing ability and stamina of thoroughbreds. In this study, we compared the frequency of mutations in the MSTN gene in several horse breeds, including 1,433 Jeju horses. Among the mutations (ECA18 g.66493737C>T) in the MSTN gene, the long-distance aptitude genotype (TT) was found to have a frequency of 0.826 in Jeju horses, which was higher than that in Halla horses (0.285) and thoroughbreds (0.252). The genotypes and arrival records of Jeju horses were compared according to various distances (400 m, 800 m, 900 m, 1,000 m, 1,110 m, and 1,200 m). According to the results, the CT type showed a faster-reaching record than the TT type in races of less than 1,000 m. However, almost identical results were confirmed in races over 1,110 m. This study suggests that the MSTN mutation in Jeju horses may be related to race distance aptitude. In future research, the data in this study can be used for developing markers related to race distance aptitude and racing abilities in Jeju horses.

• Korean Journal of Veterinary Research
• /
• v.51 no.4
• /
• pp.297-301
• /
• 2011

The racehorses that under arthroscopic surgery due to be injured his limbs were studied during exercise or training at Busan Race Park from 2005 to 2010. Rate of arthroscopic surgical treatments was 1.4% (63/4,642). Affected bones were radius, radial carpal bone, third carpal bone, proximal phalanx, third metacarpal bone, femur, tibia, proximal sesamoid bone and intermediate carpal bone. The lesions were fracture, chip fracture, slap fracture, osteochonrosis, and osteochondrotitis dissencans. Number of patients under arthroscopic surgery were 63. Success horses of returned to racetrack or tried to return to racetrack were 58, and 5 horses were in training or resting at the time of publication. Success horses of returned to their previous use in the patients were 49 horses (84.4%) and no returned to the racetrack were 9 horses (15.6%) in 58 horses.

• Journal of Animal Science and Technology
• /
• v.50 no.6
• /
• pp.741-746
• /
• 2008

The objective of this study was to estimate the effects of change in body weight on racing time in Thoroughbred racehorses, using total 8,197 horses and 155,656 racing records collected from Korea Racing Association(KRA). The average body weight of the racehorses was 449kg, and the average body weights of stallion, gelding and mare were 460kg, 454kg and 441kg, respectively. Body weight of stallion was the greatest. The considerable loss of body weight was observed in March, April and May for mare, and in May, Jun and July for stallion and gelding. Overall, the body weight of the racehorses decreased in spring and summer, and increased in autumn and winter. The estimated heritability and repeatability for racing time were 0.237 and 0.525, respectively. The heritability for body weight estimated from total records was 0.612. The estimated heri- tabilities for body weight were 0.472, 0.578 and 0.555 for gelding, stallion and mare, respectively. As the change of body weight was greater than ±10kg, the racing time increased significantly. When the body weight changed more than ±20kg in comparison to the changes of body weight of ±5kg, the racing time increased by 0.3 second. When the change of body weight was ±0.5% of body weight, the racing time was the best(fastest). When the change of body weight was more than ±2.5%, racing performance decreased considerably.

• Journal of Veterinary Clinics
• /
• v.26 no.1
• /
• pp.69-71
• /
• 2009

A 2-year-old, female Thoroughbred racehorse was referred to the Equine Hospital of Korea Racing Authority. The horse was presented with fluctuant swelling at the base of the left temporal ear tooth. We performed physical examination, radiography and ultrasonography, and diagnosed as dentigerous cyst on the left temporal ear tooth-(dentigerous cyst). The horse was treated with removal of a dentigerous cyst(aural fistula). After surgical procedure for 12 days, the patient was recovered completely.

• Journal of Animal Science and Technology
• /
• v.50 no.3
• /
• pp.309-314
• /
• 2008

The objective of this study was to estimate effects of the condition of racetrack on racing time in Thoroughbred racehorses, using 148,865 racing records for 8,189 heads that collected from KRA(Korea Racing Association). The results obtained were as follows. Based on moisture contents, the condition of racetrack was classified into Heavy, Good, Soft, Yielding and Sloppy. The condition of racetrack for last 12 years was 40.7%, 34.4%, 14.4%, 8.7% and 1.8% for Heavy, Good, Soft, Yielding and Sloppy, respectively. The frequency of heavy condition for racetrack was the highest and those of Yielding and Sloppy were relatively low. On the other hand, the frequency of heavy condition for racetrack was increased in spring and winter, whereas frequency of sloppy racetrack was increased in summer. The frequency of good condition was the highest in autumn. The regression coefficients of moisture contents in racetrack for racing time by racing distance ranged from －0.068~－0.162 seconds and the racing time was faster in sloppy condition than other track conditions. The time differences between Heavy and Sloppy ranged from －1.47~－3.41 seconds by distance.

• Korean Journal of Veterinary Research
• /
• v.50 no.3
• /
• pp.253-257
• /
• 2010

A 3-year-old female Thoroughbred racehorse was presented following the accidental oral and skin administration of amitraz. This case report describes the clinical signs and the treatment of this horse. Clinical signs of amitraz toxicosis are associated with the stimulation of alpha2-adrenergic receptors. Amitraz is seldom fatal because the effects can be reversed by alpha2-adrenergic antagonists. The horse displayed typical clinical signs of colic, including pawing, small hard drops, tranquillisation, depression, ataxia, muscular incoordination and impaction colic lasting up to 7 days. The syndrome was accompanied by mild dehydration. The horse survived after persistent symptomatic treatment, including the giving of intravenous fluids, antibiotics, multiple doses of mineral oil per os, nonsteroidal anti-inflammatory drugs and dexamethasone intramuscularly and intravenously.

• Journal of Life Science
• /
• v.25 no.11
• /
• pp.1304-1310
• /
• 2015

The period circadian clock gene 3 (PER3) plays a role in the mammalian circadian clocksystem. A regular exercise regime may affect the PER3 transcription in skeletal muscle. Although the effects of day length on circadian and circannual processes are well established in humans and mice, the influence of exercise on these processes in the horse has not been investigated. The present study investigated the expression of the PER3 gene following exercise in a thoroughbred breed of Korean horse. In addition, a comprehensive in silico nonsynonymous single nucleotide polymorphism (nsSNP) analysis of the horse PER3 gene and predicted effects of nsSNPs on proteins were examined. The expression of PER3 in skeletal muscle was significantly upregulated after exercise. Four nsSNPs were functionally annotated and analyzed by computational prediction. The total free energy and RMSD values of PER3 gene showed causative mutations. The results showed that nsSNP s395916798 (G72R) was associated with residues that have stabilizing effects on structure and function of PER3 gene. This study documented role of PER3 gene in phenotypic adaptation related to exercise in skeletal muscle. Further, the SNPs in PER3 could serve as useful biomarkers of early recovery after exercise in racehorses.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.29 no.4
• /
• pp.355-364
• /
• 2009

This research was conducted to investigate the group and individual behavioral patterns of thoroughbred mares which are important for raising race-horses, in paddoks (pregnant) and pastures (nursing). In a group of nursing mare, eating 62%, standing resting 31%, drinking 3%, lying resting 1%, walking 1% and nursing 2% were observed, although no running was observed. Average time spent on individual behavior of mares (3 heads) was eating 295 min (55%), standing resting 193 min (36%), walking 18 min, drinking 18 min (3%), nursing 13 min (2%), lying resting 6 min (1%). Average 11 times of grooming, 2 times of urinating, and 1 time of feces were observed for mare in pasture. 48% of standing resting, 44% of eating, 2% of lying resting, 4% of walking, and 2% of drinking were revealed for pregnant mares in paddock. Average individual behavioral pattern of pregnant mares (3 heads) was 52% of eating, 40% of standing, 6% of walking, and 2% of drinking. Average 15 times of grooming, 1 time of urinating, 3 times of feces, 1 time of fighting, and 2 times of rolling were observed for pregnant mares in paddock. For moving patterns, pregnant mares were inclined to concentrate on where the nearby paddok is close to.

• Journal of Veterinary Clinics
• /
• v.31 no.4
• /
• pp.278-281
• /
• 2014

The object of this study was to determine rate of ability restoration after arthroscopic surgeries in Thoroughbred racehorses. The racehorses that under arthroscopic surgery due to be injured his limbs were studied during exercise or training at Busan Race Park from 2005 to 2010. Rate of arthroscopic surgical treatments was 1.4% (63/4642). The results of arthroscopic surgery for the removal of osteochondral fragments from 70 limbs in 63 horses are reported. Number of patients under arthroscopic surgery were 63 and 58 horses were recovered from the surgeries and 5 horses were in training or resting at the time of publication. Only 52 of 58 horses had previous race experiences before the surgeries. Success horses of returned to the same level of performance were 31 horses (59.6%) and failed horses were 21 horses (40.4%). Average resting periods in success and failed horses were 7 months and 8.8 months, respectively. Resting periods in success horses were shorter than failed horses.

• Journal of Veterinary Clinics
• /
• v.29 no.6
• /
• pp.431-434
• /
• 2012

This study was conducted to survey red blood cell (RBC) antigens Aa, Ca and Qa types, which are considered to be the most significantly associated with occurrence of neonatal isoerythrolysis, and the results are expected to provide valuable informations in organization of breeding plan, hence preventing the disease. Blood samples were collected from 262 Thoroughbred horses in Jeju island. Two percent cell suspension has been prepared from each sample and they were tested by indirect antiglobulin test. Of the 226 mare's samples, 9(3.98%) were Aa negative, 8(3.54%) were Ca negative, 17(7.52%) were Qa negative. Of the 36 Stallion's samples, 1(2.78%) was Aa negative, 3(8.33%) were Ca negative, 3(8.33%) were Qa negative. On the basis of these data, a database for breeding compatability could be set, and it would play an important role as a reference for arranging the mating partners.