• Journal of Microbiology and Biotechnology
• /
• 제19권9호
• /
• pp.1041-1050
• /
• 2009

Equine respiratory disease is a common cause of poor performance and training interruptions. The higher incidence rate of infectious upper respiratory disease (IURD) in thoroughbred racehorses at the Seoul Race Park coincided with the frequent stabling season, shorter stabling periods, and younger ages in this study. Incidence rates were also correlated with significantly lower proportions of cells expressing MHC class II-, CD2 antigen-, $CD4^+$- or $CD8^+$-T lymphocyte-, and B lymphocyte in IURD patients compared with healthy control groups in the summer and fall and in 2-and-3-year-old groups. The data suggested that movement and new environments may have resulted in immunosuppression and inappropriate responses to respiratory pathogens in IURD patients. The IURD incidence decreased with age, perhaps by the acquisition of immunity, and study results suggested that immunologic protection was associated with IURD, particularly in young thoroughbred racehorses. Streptococci isolates were identified in 11 of 72 IURD horses, and 3 of these isolates were identified as Streptococcus. equi subsp. equi. S. equi subsp. zooepidemicus was isolated from 2 of 23 IURD horses in the spring (8.7%), 5 of 23 in the summer (21.7%), and 1 of 6 in winter (16.7%). S. equi subsp. zooepidemicus (5%) was also identified in 3 of 61 isolates from clinically normal horses. Racetracks should implement anti-IURD protective measures by assessing the capacity of equine immunologic protection at the Park and by limiting the introduction of specific respiratory pathogens (such as S. equi subsp. equi) by preventing the access of infected but subclinical horses with a specified respiratory pathogen-free certification system prior to Park entry.

• Asian-Australasian Journal of Animal Sciences
• /
• 제19권11호
• /
• pp.1632-1637
• /
• 2006

We studied the changes in biochemical markers of bone metabolism in growing Thoroughbred horses. Serum osteocalcin (OC), as a marker for bone formation, and carboxy-terminal propeptide of type-I collagen (PICP), as a marker for bone formation, carboxy-terminal telopeptide of type-I collagen (ICTP), as a marker for bone resorption, were determined in nine clinically healthy horses from 3 d to 17 mo of age. The BW and withers height (WH) increased during the study. On the other hand, a rapid reduction in body weight gain (BWG) was observed between 1 mo and 9 mo of age and a rapid reduction in withers height gain was observed between 1 mo and 5 mo of age. The serum markers decreased significantly with increasing age. In particular, dramatic changes in serum markers occurred between 3 d to 1 wk and 5 to 7 mo of age in these horses, which suggests that bone turnover rapidly decreased after birth. On the other hand, the ratio of PICP to ICTP decreased through the experiment. This result suggests that the reduction in bone formation exceeded that of bone resorption. There was a significant correlation between markers and growth parameters, except for the correlation between PICP and BWG on single linear regression analysis. Serum OC and ICTP were affected by the WH in multiple linear regression analysis. These results indicated that the age-related variation in serum biochemical markers of bone metabolism reflected bone growth, but neither BW nor BWG. Therefore, we consider that changes in bone modeling are the major factor affecting the levels of serum biochemical markers by 17 mo of age in horses.

• Journal of Animal Science and Technology
• /
• 제63권3호
• /
• pp.651-661
• /
• 2021

This study aimed to investigate whether breed, sex, and age affected temperament differently (more or less neophobic) in mature horses during a novel object test. The study included Jeju crossbred (n = 12, age = 9.42 ± 4.57 y), Thoroughbred (n = 15, age = 10.73 ± 3.09 y), and Warmblood horses (n = 12, age = 13.08 ± 3.55 y) with the females (n = 22, age = 11.36 ± 4.24 y) and geldings (n = 17, age = 10.65 ± 3.66 y). Jeju crossbreds (Jeju horse × Thoroughbred) are valuable considering their popular usage in Korea, but limited studies have explored temperament of Jeju crossbred horses. A trained experimenter touched the left side of the neck with a white plastic bag (novel object). The test ended when the horse stopped escape response and heart rate (HR) dropped to baseline. Behavioral score and escape duration were measured as behavioral variables. Multiple variables related to HR and heart rate variability (HRV) were measured to reflect emotional state. These included basal HR (BHR), maximum HR (MHR), delay to reach maximum heart rate (Time to MHR), standard deviation of beat-to-beat intervals (SDNN), root mean square of successive differences (RMSSD), and ratio of low to high frequency components of a continuous series of heartbeats (LF/HF). Statistics revealed that Thoroughbreds had significantly higher behavioral scores, and lower RMSSD than Jeju crossbreds (p < 0.05), suggesting greater excitement and fear to the novel object in Thoroughbreds. None of the behavioral or cardiac parameters exhibited sex differences (p < 0.05). Age was negatively correlated with SDNN and RMSSD (p < 0.05), indicating that older horses felt more anxiety to the novelty than younger horses. Thoroughbreds and females had distinct correlations between behavioral and HRV variables in comparison with other groups (p < 0.05), implying that escape duration might be a good indicator of stress, especially in these two groups. These results are expected to improve equine welfare, safety and utility, by providing insights into the temperament of particular horse groups, to better match reactivity levels with specific functions.

• Molecules and Cells
• /
• 제40권10호
• /
• pp.796-804
• /
• 2017

Endogenous retroviruses (ERVs) have been integrated into vertebrate genomes and have momentously affected host organisms. Horses (Equus caballus) have been domesticated and selected for elite racing ability over centuries. ERVs played an important role in the evolutionary diversification of the horse genome. In the present study, we identified six equine ERV families (EqERVs-E1, I1, M2, P1, S1, and Y4), their full-length viral open reading frames (ORFs), and elucidated their phylogenetic relationships. The divergence time of EqERV families assuming an evolutionary rate of 0.2%/Myr indicated that EqERV-S3 (75.4 million years ago; mya) on chromosome 10 is an old EqERV family and EqERV-P5 (1.2 Mya) on chromosome 12 is a young member. During the evolutionary diversification of horses, the EqERV-I family diverged 1.7 Mya to 38.7 Mya. Reverse transcription quantitative real-time PCR (RT-qPCR) amplification of EqERV pol genes showed greater expression in the cerebellum of the Jeju horse than the Thoroughbred horse. These results could contribute further dynamic studies for horse genome in relation to EqERV gene function.

• Journal of Animal Science and Technology
• /
• 제58권11호
• /
• pp.40.1-40.5
• /
• 2016

Background: Currently about 26,000 horses are breeding in Korea and 57.2% (14,776 horses) of them are breeding in Jeju island. According to the statistics published in 2010, the horses breeding in Jeju island are subdivided into Jeju horse (6.1%), Thoroughbred (18.8%) and Halla horse (75.1%). Halla horses are defined as a crossbreed between Jeju and Thoroughbred horses and are used for horse racing, horse riding and horse meat production. However, little research has been conducted on Halla horses because of the perception of crossbreed and people's weighted interest toward Jeju horses. Method: Using 17 Microsatellite (MS) Markers recommended by International Society for Animal Genetics (ISAG), genomic DNAs were extracted from the hair roots of 3,880 Halla horses breeding in Korea and genetic diversity was identified by genotyping after PCR was performed. Results and conclusion: In average, 10.41 alleles (from 6 alleles in HTG7 to 17 alleles in ASB17) were identified after the analysis using 17 MS Markers. The mean value of $H_{obs}$ was 0.749 with a range from 0.612(HMS1) to 0. 857(ASB2). Also, it was found that $H_{\exp}$ and PIC values were lowest in HMS1 (0.607 and 0.548, respectively), and highest in LEX3(0.859 and 0.843, respectively), and the mean value of $H_{\exp}$ was 0.760 and that of PIC was 0.728. 17 MS markers used in this studies were considered as appropriate markers for the polymorphism analysis of Halla horses. The frequency for the appearance of identical individuals was $5.90{\times}10^{-20}$ when assumed as random mating population and when assumed as half-sib and full-sib population, frequencies were $4.08{\times}10^{-15}$ and $3.56{\times}10^{-8}$, respectively. Based on these results, the 17 MS markers can be used adequately for the Individual Identification and Parentage Verification of Halla horses. Remarkably, allele M and Q of ASB23 marker, G of HMS2 marker, H and L of HTG6 marker, L of HTG7 marker, E of LEX3 marker were the specific alleles unique to Halla horses.

• 대한수의학회지
• /
• 제43권1호
• /
• pp.25-29
• /
• 2003

This study was carried out to investigate a usefulness of the microsatellite DNA markers for parentage verification of Thoroughbred (TB) horses. 9 TB horses samples were genotyped for nine international minimum standard markers (AHT4, 5, ASB2, HMS3, 6, 7, HTG4, 10, and VHL20), and the additional panel of four markers, ASB17, CA425, LEX33, and TKY321. This methods consisted of multiplexing PCR procedures, and it showed reasonable amplification of all PCR products. Genotyping was performed with an ABI 310 genetic analyzer. Foal I was excluded according to principles of Mendelian genetics in AHT4 (H/K), ASB2 (Q/Q), HMS3 (I/P), HTG4 (M/O), HTG1O (K/R), VHL20 (M/P), ASB17 (F/N), LEX33 (M/O), and TKY321 (G/I) markets. Foal II was excluded with markers AHT5 (K/M), ASB2 (M/N), HMS7 (N/N), HTG1O (K/K), VHL20 (I/I), ASB17 (F/F) and TKY321 (G/I). Foal III was excluded with markers AHT4 (O/O), AHT5 (K/K), ASB2 (M/R), HMS6 (M/P), HMS7 (O/O), HTG10 (R/S), VHL20 (L/M), and ASB17 (N/O). These results suggest that the present DNA typing is so useful for parentage verification of TB horses.

• Asian-Australasian Journal of Animal Sciences
• /
• 제30권5호
• /
• pp.728-735
• /
• 2017

Objective: This study was performed to reveal the molecular structure and expression patterns of horse glutamate-cysteine ligase catalytic subunit (GCLC) and glutamate-cysteine ligase modifier subunit (GCLM) genes whose products form glutamate cysteine ligase, which were identified as differentially expressed genes in the previous study. Methods: We performed bioinformatics analyses, and gene expression assay with quantitative polymerase chain reaction (qPCR) for horse GCLC and GCLM genes in muscle and blood leukocytes of Thoroughbred horses Results: Expression of GCLC showed the same pattern in both blood and muscle tissues after exercise. Expression of GCLC increased in the muscle and blood of Thoroughbreds, suggesting a tissue-specific regulatory mechanism for the expression of GCLC. In addition, expression of the GCLM gene increased after exercise in both the blood and muscle of Thoroughbreds. Conclusion: We established the expression patterns of GCLC and GCLM in the skeletal muscle and blood of Thoroughbred horses in response to exercise. Further study is now warranted to uncover the functional importance of these genes in exercise and recovery in racehorses.

• 대한수의학회지
• /
• 제40권4호
• /
• pp.683-689
• /
• 2000

The present study was carried out to investigate the blood markers of Thoroughbred horses (TB) The blood red cell types and blood protein types (biochemical polymorphisms) were tested from 1,125 Thoroughbred horses by serological and electrophoretic procedures, and their phenotypes, gene frequencies, heterozygosity, polymorphic information content values and exclusion probability were estimated. The blood group and biochemical polymorphism phenotypes observed with high frequency were Aaf(91.7%), Ca(94.7%), K-(94.5%), Ua(75.9%), P-(50.6%), Qabc(82.6%), ALB-BB(67.7%), GC-FF(92.7%), AIB-KK(99.6%), ES-II(77.9%), TF-DF1(23.6%), PI-LL(23.2%), HB-B2B2(73.6%), PGD-FS(45.4%) and genotypes Dcgm/dk(16.9%), Dbcm/cgm(13.6%), Dbcm/dk(11.9%), Dcegmn/cegmn(10.0%), Dcgm/cgm(8.7%) in TB. Alleles observed with high frequency were Aaf(0.796), Ca(0.769), Ddk(0.266), Dcgm(0.261), Dbcm(0.211), K-(0.972), P-(0.710), Qabc(0.565), Q-(0.368), Ua(0.509), $HB^{B2}$(0.858), $PGD^F$(0.634), $ALB^B$(0.825), $GC^F$(0.927), $AIB^K$(0.998), $ES^I$(0.881), $TF^{F1}$(0.346), $TF^D$(0.319), $TF^{F2}$(0.184), $PI^L$(0.479), $PI^N$(0.214), $PI^U$(0.116) in TB. The heterozygosity, polymorphic information content (PIC) and exclusion probability (PE) were calculated. The mean heterozygosity and PIC value were 0.3899 and 0.3375, respectively. The highest heterozygosity and PIC were estimated 0.7834 and 0.7492 in blood group D locus, respectively. The cumulated PE obtained by blood groups and biochemical polymorphisms was 0.9813.

• Asian-Australasian Journal of Animal Sciences
• /
• 제31권8호
• /
• pp.1110-1118
• /
• 2018

Objective: This study was intended to identify genes positively selected in Thoroughbred horses (THBs) that potentially contribute to their running performances. Methods: The genomes of THB and Jeju horses (JH, Korean native horse) were compared to identify genes positively selected in THB. We performed cross-population extended haplotype homozygosity (XP-EHH) and cross-population composite likelihood ratio test (XP-CLR) statistical methods for our analysis using whole genome resequencing data of 14 THB and 6 JH. Results: We identified 98 (XP-EHH) and 200 (XP-CLR) genes that are under positive selection in THB. Gene enrichment analysis identified 72 gene ontology biological process (GO BP) terms. The genes and GO BP terms explained some of THB's characteristics such as immunity, energy metabolism and eye size and function related to running performances. GO BP terms that play key roles in several cell signaling mechanisms, which affected ocular size and visual functions were identified. GO BP term Eye photoreceptor cell differentiation is among the terms annotated presumed to affect eye size. Conclusion: Our analysis revealed some positively selected candidate genes in THB related to their racing performances. The genes detected are related to the immunity, ocular size and function, and energy metabolism.

• 한국임상수의학회지
• /
• 제15권1호
• /
• pp.14-21
• /
• 1998

Ultrasonogram for kidney, spleens liver, intestine and heart was evaluated 11 Chriu horses and 14 Thoroughbred horse. The kidney was determined at both flan and both 17th intercostal spaces. The spleen was determined at the left 13-17 intercom spacer and the liver was determined at the right 7-13 intercostal space. The heart was determined at the right 4-6 intercostal space and left 3-6 intercostal space. The length, of rig kidney at the Thoroughbred horse, Thoroughbred foul, Cheju horse and Cheju foul were 16.2, 12.6, 13.1 and 11.2 mm, respectively. The width of right kidney at the Thoroughbed horse, Thorughbred foul, Cheju horse and Cheju foul were 5.4, 4.3, 4.6 and 4.2 mm, respectively. The depth of right kidney at the Thoroughbred horsed Thoroughbred foul, Cheju horse and Chrju foul were 5.2, 4.4, 4.5 and 4.3 mm, respectively. Similar ultrasonographic measurements were obtained for the left kidney, The left ventricular end-diastolic diameter at the Thoroughbred horse, Thoroughbred fouls Cheju horst and Cheju foul were 107, 83, 85 and 73 mm, respectively. The left ventricular end-systolic diameter were at the Thoroughbred horse, Thoroughbred foul, Cheiu horse and Cheiu foul were 63, 52, 53 and 45 mm, respectively. Also, the interventricular septum in end-diastole, interventricular septum in end-systoles left ventricular wall end-diastoles left ventricular wall end-systoles right ventricular end-diastole diameter, aorta and left atrium at t Thoroughbred horse, Thoroughbred foul, Chriu horse and Chriu foul were measured. Experimental renal stone and enterolith of colon were observed by ultrasonography.