Schaefer EA, Edman J, Magdesian KG.Hematology is a diagnostic tool used to evaluate the health status of horses. However, breed differences are often not considered. Objective: The objective was to compare complete blood count variables among Warmbloods, Thoroughbreds, and stock horses (SH). Methods: Ninety-six healthy horses were grouped by breed (Warmbloods, Thoroughbreds, and SH). Samples were collected through venipuncture for complete blood count analysis. One-way ANOVA with Tukey's tests or Kruskal-Wallis with Dunn's post hoc tests were used to compare hematologic variables among groups. Results: Warmbloods had a signific...
Massie S, Bayly W, Ohmura H, Takahashi Y, Mukai K, Lu00e9guillette R.Comparatively little is known regarding the initial cardiorespiratory response of young racehorses to training. The objectives were to compare physiological parameters before and after introductory training and determine whether young Thoroughbreds show endoscopic signs of exercise-induced pulmonary hemorrhage (EIPH). Ten Thoroughbreds (20-23 months) underwent 12-weeks of introductory training, including weekly speed sessions. Two 600 m high-speed exercise tests (HSET) were performed following weeks 4 and 12 while wearing a validated ergospirometry facemask. Peak oxygen consumption (V̇Opk...
Busechian S, Orvieto S, Nocera I, Rueca F.Equine Gastric Ulcers Syndrome (EGUS) is a worldwide disease present in equids of different breeds, activity levels, and age groups. It is divided into two different illnesses: Equine Squamous Gastric Disease (ESGD) affecting the squamous mucosa and Equine Glandular Gastric Disease (EGGD) affecting the glandular mucosa. The historical horserace is a traditional competition that is common in Italy. They can be divided into two different types: speed races and jousting tournaments. Anglo-Arabians and Thoroughbreds are used for the two competitions with training and management systems similar to ...
Neville E, Pigott J.To describe the clinical presentation of a Thoroughbred filly with acute hemoperitoneum from a splenic source immediately after racing. Methods: A 3-year-old Thoroughbred filly used for racing and that had raced shortly before presentation to the hospital. Unassigned: On presentation, the filly was quiet, alert, and responsive with a heart rate of 76 beats/min, pale mucous membranes, and absent borborygmi. All other physical examination parameters were within normal limits. Abdominal ultrasound was performed and revealed echogenic free abdominal fluid and a splenic hematoma. Abdominocentesis y...
Forbes B, Ho W, Parkes RSV, Sepulveda Caviedes MF, Pfau T, Martel DR.Racehorses commonly train and race in one direction, which may result in gait asymmetries. This study quantified gait symmetry in two cohorts of Thoroughbreds differing in their predominant exercising direction; we hypothesized that there would be significant differences in the direction of asymmetry between cohorts. Methods: 307 Thoroughbreds (156 from Singapore Turf Club (STC)-anticlockwise; 151 from Hong Kong Jockey Club (HKJC)-clockwise) were assessed during a straight-line, in-hand trot on firm ground with inertial sensors on their head and pelvis quantifying differences between the minim...
Park T, Yoon J, Yun Y, Unno T.Exercise plays an important role in regulating energy homeostasis, which affects the diversity of the intestinal microbial community in humans and animals. To the best of the authors' knowledge, few studies have reported the associations between horse gut microbiota along with their predicted metabolic activities and the athletic ability of Jeju horses and Thoroughbreds living in Korea. This study was conducted to investigate the association between the gut microbiota and athletic performance in horses. This study sequenced the V3 and V4 hypervariable regions of the partial 16S rRNA genes obta...
Aminou O, Badaoui B, Machmoum M, Piro M.The International Society for Animal Genetics (ISAG) currently advocates for a transition towards single nucleotide polymorphism (SNP) markers as a potential alternative for equine parentage verification. To ascertain the efficacy of this transition, it is imperative to evaluate the performance of parentage testing using SNPs in juxtaposition with short tandem repeats (STRs). As per ISAG's recommendation, we used an equine genotyping-by-sequencing panel with 144 SNPs for this purpose. Equine parentage is currently realized using 16 microsatellites (STRs) excluding the LEX3 marker. In this stud...
Shoemaker S, Wang Y, Sellon D, Gold J, Fisher A, Bagshaw J, Leguillette R, Sanz M, Bayly W.Little has been reported regarding the prevalence and severity of exercise-induced pulmonary hemorrhage (EIPH) in 2-year-old Thoroughbred racehorses. Objective: Evaluate EIPH prevalence and severity and its association with performance, speed index, furosemide administration, race distance, and track surface. Methods: A total of 830 2-year-old Thoroughbreds. Methods: Prospective blinded observational study. Videoendoscopy was performed 30 to 60 minutes postrace at 15 American racetracks. Three blinded observers independently assigned an EIPH grade (0-4) to each video, and prevalence and seve...
Al-Kass Z, Morrell JM.Artificial insemination (AI) is used frequently in the breeding of sport horses, apart from Thoroughbreds. Most AIs are carried out with cooled semen rather than frozen semen because of the difficulties in identifying a protocol that is suitable for freezing most ejaculates and the necessity to inseminate close to ovulation because of the short life of the thawed spermatozoa. More widespread use of frozen semen would improve biosecurity, allow greater choice of stallions, and offer more flexibility when managing deliveries of semen to the stud. It would even decrease the amount of antibiotics ...
Miglio A, Falcinelli E, Cappelli K, Mecocci S, Mezzasoma AM, Antognoni MT, Gresele P.Training has a significant effect on the physiology of blood coagulation in humans and in horses. Several hemostatic changes have been reported after exercise in the horse but data available are inconclusive. The aim of this study was to investigate platelet activation and primary platelet-related hemostasis modifications in young never-trained Thoroughbreds in the first incremental training period in order to improve knowledge on this topic. Twenty-nine clinically healthy, untrained, 2-year-old Thoroughbred racehorses were followed during their incremental 4-month sprint exercise training. Bl...
Ciamillo SA, Wulster KB, Gassert TM, Richardson DW, Brown KA, Stefanovski D, Ortved KF.Catastrophic injuries of the fetlock joints occur in Thoroughbred racehorses and are preceded by stress-induced bone injury. Early detection of subchondral bone injury is essential to prevent irreversible damage or bone failure. Objective: To investigate the use of standing, robotic cone-beam computed tomography (CBCT) for assessing longitudinal changes in subchondral bone morphology and pathology of the fetlock joints associated with race training in young Thoroughbreds. Methods: Observational cohort study. Methods: Forty-one 2-year-old Thoroughbred racehorses were recruited prior to the star...
Racehorses may experience exercise-induced bronchodilation or bronchoconstriction, with potential differences between healthy and asthmatic individuals. Objective: To identify exercise-related lung function variations by oscillometry in racehorses, compare lung function between healthy and mild equine asthma (MEA) horses, assess oscillometry's potential as a predictor of racing fitness. Methods: Prospective case-control clinical study. Methods: Fourteen Thoroughbred racehorses (5 healthy, 9 MEA) underwent a protocol including respiratory oscillometry at rest, exercise with fitness monitoring, ...
Peat FJ, Kawcak CE, McIlwraith CW, Keenan DP, Berk JT, Mork DS.Radiological findings in the proximal sesamoid bones (sesamoids) are a persistent source of controversy at Thoroughbred sales, due to inconsistent classification and conflicting assignment of potential clinical importance. Objective: To define the prevalence of sesamoid findings on sales repository radiographs in yearling and 2-year-old Thoroughbreds and to analyse associations with racing performance. To track the changes in sesamoid findings between 1 and 2 years of age in horses that present for sale at both ages. Methods: Prospective cohort study using an enrolled sample. Methods: Horses...
Lawson JM, Verheyen K, Smith KC, Bryan JS, Foote AK, de Mestre AM.Excessive umbilical cord length (UCL) is associated with equine pregnancy loss. However, a lack of UCL reference values makes it difficult to define excessive UCL. Further, factors associated with differences in UCL are poorly understood. Objective: To (i) report the total, allantoic and amniotic UCL in healthy term pregnancies in Thoroughbreds, (ii) describe the relationship between gestational age and UCL, fetal weight and crown rump length (CRL) using clinically normal pregnancies (CNPs) from mares dying during gestation, and (iii) identify associations between UCL and maternal age and pari...
Sawesi OK, Elbaz AK, Mahmoud AS, Duro EM, Alteab AA, Milad KK, Bennuor EM.Hematological evaluation is an important step for health assessment in equine medicine. Besides biochemical tests, that evaluation could be pivotal for diagnosis, prognosis, and treatment monitoring. In Libya, the horse population has drastically increased in the last years, and hitherto, no report addressed the reference hematological values for the existing equine breeds. Unassigned: This study aimed to establish the reference for hematological indices of traditional equestrian and stud-farm equine breeds in Western Libya in regard to some variables such as individual characteristics, manage...
Yoo H, Lee S, Shin KY, Seo JP.This study aimed to describe the computed tomographic (CT) dimensions and the contrast attenuation of the eye in Jeju horses and Thoroughbreds. We evaluated the CT images of 10 Jeju horses and 6 Thoroughbreds without ocular abnormalities to assess the ocular dimensions and contrast attenuation. The following measurements showed significant differences between Jeju horses and Thoroughbreds (P<0.05): the diameters of the lens, globe, posterior segment, orbital fossa, and lateromedial distance of the anterior chamber; and the Hounsfield units of the vitreous body. This study describes the CT a...
Mouncey R, Arango-Sabogal JC, de Mestre A, Verheyen KKL.Early-life locomotor activity during turn out may alter susceptibility to musculoskeletal disease and injury via modulation of behaviours and tissue development during growth. Objective: Investigate associations between turn out practices and rates of musculoskeletal disease and injury in young Thoroughbreds on stud farms in the United Kingdom. Methods: Prospective cohort. Methods: Daily records were kept on location and duration of turn out for 134 Thoroughbred foals on six stud farms, from birth until leaving the farm or study exit. Data on veterinary-attended episodes of musculoskeletal dis...
Ratcliffe TOC, Robinson P, Rosanowski SM.To evaluate and compare the prognosis for Thoroughbred racehorses to return to galloping and racing with injuries to the palmaroproximal metacarpus diagnosed with MRI. Methods: 29 flat racing Thoroughbreds at the Hong Kong Jockey Club that underwent MRI between 2014 and 2022. Methods: Clinical, radiographic, ultrasonographic, and MRI reports were collected from veterinary clinical records, and these were combined with training and racing data. Horses were categorized on the basis of MRI diagnosis: (1) proximal suspensory ligament (PSL) involvement only, (2) PSL and concurrent proximal third me...
Spoormakers TJP, Veraa S, Graat EAM, van Weeren PR, Brommer H.Data on equine lumbar pathology hardly exist in breeds other than Thoroughbreds. Objective: To describe pathological changes of the osseous lumbar vertebral column in Warmblood horses, Shetland ponies and Konik horses. Methods: Descriptive post-mortem study. Methods: The lumbar vertebral columns of 34 Warmblood horses, 28 Shetland ponies, and 18 Konik horses were examined by computed tomography (CT). Osteoarthritis (OA) of articular processes (APJs), OA of intertransverse joints (ITJs), intervertebral disc (IVD) mineralisation, impingement of spinous (SPs) and transverse (TPs) processes and sp...
Ryu SH, Sohn Y, Forbes E, Jeon HS, An SJ, Kim BS, Kyung SG, Lee I.The incidence of colic and the outcomes of colic surgery have not been surveyed in racetracks in Korea. Objective: 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 horse...
Atroshchenko M, Dementieva N, Shcherbakov Y, Nikolaeva O, Azovtseva A, Ryabova A, Nikitkina E, Makhmutova O, Datsyshin A, Zakharov V, Zaitsev A.Horses were domesticated later than other farm animals. Horse breeds have been selectively developed by humans to satisfy different needs and purposes. The factory and indigenous breeds are of particular interest, having been bred in purity for many centuries without the addition of foreign blood. Data from 31 stud farms, as well as ranches, located in fifteen regions of the Russian Federation were used in this work. DNA was sampled from 102 stallions of 11 breeds: Arabian, Akhal-Teke, Don, Orlov Trotter, Vladimir Heavy Draft, Russian Heavy Draft, Soviet Heavy Draft, Kabardin, Yakut, Tuva, and...
Martineau M, Kokabi E, Taiebi A, Lefebvre S, Pradier S, Jau00ff M, Tardy F, Leon A.Mycoplasmas are pathogens involved in respiratory disorders of various animal hosts. In horses, Mycoplasma (M.) equirhinis is the species most frequently detected in clinical respiratory specimens, with a prevalence of 12-16%, but its clinical implication in equine respiratory disorders remains unclear. Here we screened 1948 clinical specimens for the presence of M. equirhinis. The samples were both tracheal washes (TW) and bronchoalveolar lavages (BAL) collected by veterinarians in France in day-to-day work between 2020 and 2022. The samples were associated with a standardized form that serve...
Ishimaru M, Okano A, Matsui A, Murase H, Korosue K, Akiyama K, Taya K.The effects of an extended photoperiod (EP) on body composition of Thoroughbreds colts and fillies from December at one year old to April at two years old were investigated. Seventy-three Thoroughbreds reared and trained in Hidaka Training and Research Center, Japan Racing Association, Hokkaido were used. Forty-one horses were under the EP conditions from December 20 to April 15, and the 32 horses were under natural light alone as the control group. Body weight (BW), rump fat thickness (RFT), fat free mass (FFM) and percentage of fat (%F) were used as parameters of body composition. The presen...
Katz LM, Gough K, McGivney CL, McGivney B, Sides RH, Hill EW, Bayly WM.Sex effects on ventilatory and oxygen consumption (V̇O) measurements during exercise have been identified in humans. This study's aim was to evaluate the hypothesis that there are sex effects on ventilatory and V̇O measurements in exercising, untrained yearling Thoroughbreds (Tb). Forty-one Tbs (16 colts, 25 fillies; 19.8 ± 1.4 months old) were recruited. Physiological, ventilatory and exercise data were gathered from horses exercising unridden at high intensity on an all-weather track from a global positioning-heart rate unit and a portable ergospirometry system. Data were analysed with an...
Zimmermann E, Ros KB, Pfarrer C, Distl O.Malformations of the equine cervicothoracic junction affect the C6 and C7 cervical vertebrae, the T1 thoracic vertebra and in variable extent the first and second sternal ribs. To date, the clinical impact of this malformation, its prevalence and mode of inheritance in equine populations are not yet determined. We examined five skeletons for signs of malformation of the cervicothoracic junction, including three skeletons from widely used Thoroughbred stallions affected with the malformation and two skeletons serving as a comparison. The three affected historical horses were the Thoroughbred st...
Kerbert MP, Freeland RB, Verhaar N, Baker WT. The lateral trochlear ridge (LTR) of the femur is the most common predilection site for osteochondritis dissecans (OCD) in the equine stifle. The objective was to investigate the relationship between lesion size, racing performance, and sale result of Thoroughbreds with LTR OCD following arthroscopic removal as a yearling. Methods: In this retrospective study, medical records of 145 Thoroughbreds from one equine hospital that underwent surgery for LTR OCD were reviewed; the length and depth of the lesions were measured on preoperative radiographs. Horses were allocated to group S if they...
Massie SL, Bezugley RJ, McDonald KJ, Lu00e9guillette R.Arrhythmias are commonly reported in exercising horses, however due to regulatory constraints electrocardiograms (ECGs) are acquired during training but not competition, raising questions about the repeatability of findings. The aims were (1) compare training and competition arrhythmias and (2) describe the repeatability of arrhythmias during maximal-intensity exercise. A convenience sample of 52 healthy Thoroughbreds (aged 8.7 ± 2.5 years) competing in the World Professional Chuckwagon Association were obtained, totaling 152 training or competition ECGs (2-7 ECGs/horse). Speed, heart rate ...
Sobotkovu00e1 E, Kopec T, Mikule V, Kuu0159itkovu00e1 D.The aim of the research was to assess how age, sex, sire, country of foaling, country of training and race distance influenced the international racing and performance of Thoroughbreds. The research was based on performance ratings of 6216 horses assigned by the International Federation of Racing Authorities between 2004 and 2022. The most common sex was stallion (58.54 %) and more than half of the population consisted of 3- and 4-year-old horses (54.68 %). The majority of the horses had the USA as their country of foaling (25.92 %) and also as their country of training (24.87 %). The ...
Nankervis KJ, Tranquille CA, Chojnacka K, Tacey JB, Deckers I, Newton JR, Murray RC.Water treadmill (WT) exercise may induce limb and back kinematics that meet specific training and rehabilitation goals. The study aimed to investigate the effects of walk speed, at different water depths (WDs), on limb and back kinematics of six Thoroughbreds exercising on a WT. Horses walked at 2.8/4.3/5.5/6.0 km/h (i.e. 0.8/1.2/1.5/1.7 m/s) at dry, metacarpophalangeal and carpal WD. Videography captured limb movement in the sagittal plane. Motion-capture measured thoracolumbosacral flexion-extension (FE), and lateral bend (LB) ranges of movement (ROM) using skin surface markers on the sixt...
Gu00e1spu00e1rdy A, Gallagher G, Bartha B, Cseh S, Fekete SG, Somosku0151i B.The authors aimed to determine the plasma melatonin concentration in mares and their new-born foals in the early post-partum period. Blood samples were collected from the jugular vein of 53 mare-foal pairs within twelve hours after parturition. Plasma melatonin levels were measured by ELISA. The melatonin concentration, adjusted for the moment of parturition using a generalised linear model, was 34.58 pg mL-1 in mares. It was significantly lower (27.63 pg mL-1) in the new-born foals. However, the melatonin concentration declined differently by the end of the twelve hours, it decreased less in...
Godwin EE, Young NJ, Dudhia J, Beamish IC, Smith RK.Mesenchymal stem (progenitor; stromal) cell (MSC) therapy has gained popularity for the treatment of equine tendon injuries but without reports of long-term follow-up. Objective: To evaluate the safety and reinjury rate of racehorses after intralesional MSC injection in a large study of naturally occurring superficial digital flexor tendinopathy and to compare these data with those published for other treatments. Methods: Safety was assessed clinically, ultrasonographically, scintigraphically and histologically in a cohort of treated cases: 141 client-owned treated racehorses followed-up for a...
Carroll CL, Huntington PJ.Three hundred and seventy two horses of varying breeds, height and fatness were weighed and measured for height at the withers. They were assessed for condition score by adaptation of a previously published method. The heart girth and length of 281 of the horses were also measured. Weight of horses was highly correlated (P less than 0.001) with height (r2 = 0.62), condition score (r2 = 0.22) and girth2 x length (r2 = 0.90). Nomograms were constructed to predict weight from height and condition score, and girth and length measurements. Weight can also be accurately estimated from the formula: (...
Achilli A, Olivieri A, Soares P, Lancioni H, Hooshiar Kashani B, Perego UA, Nergadze SG, Carossa V, Santagostino M, Capomaccio S, Felicetti M....Archaeological and genetic evidence concerning the time and mode of wild horse (Equus ferus) domestication is still debated. High levels of genetic diversity in horse mtDNA have been detected when analyzing the control region; recurrent mutations, however, tend to blur the structure of the phylogenetic tree. Here, we brought the horse mtDNA phylogeny to the highest level of molecular resolution by analyzing 83 mitochondrial genomes from modern horses across Asia, Europe, the Middle East, and the Americas. Our data reveal 18 major haplogroups (A-R) with radiation times that are mostly confined ...
McCue ME, Bannasch DL, Petersen JL, Gurr J, Bailey E, Binns MM, Distl O, Guu00e9rin G, Hasegawa T, Hill EW, Leeb T, Lindgren G, Penedo MC....An equine SNP genotyping array was developed and evaluated on a panel of samples representing 14 domestic horse breeds and 18 evolutionarily related species. More than 54,000 polymorphic SNPs provided an average inter-SNP spacing of ∼43 kb. The mean minor allele frequency across domestic horse breeds was 0.23, and the number of polymorphic SNPs within breeds ranged from 43,287 to 52,085. Genome-wide linkage disequilibrium (LD) in most breeds declined rapidly over the first 50-100 kb and reached background levels within 1-2 Mb. The extent of LD and the level of inbreeding were highest in the ...
Carter RA, Geor RJ, Burton Staniar W, Cubitt TA, Harris PA.This study described a scoring system for the assessment of apparent neck adiposity and evaluated morphometric measurements for assessment of neck and overall adiposity. Twenty-one barren Thoroughbred mares, 13 Arabian geldings and 75 Welsh, Dartmoor, or crossbred pony mares, were clinically examined and blood samples analysed for insulin, glucose, leptin, and triglycerides. Bodyweight (BW), height, length, girth and abdominal circumferences, neck length, neck crest height and neck circumference were measured, and body condition scores (BCS) and cresty neck scores (CNS) were rated. Girth:heigh...
Hill EW, Gu J, Eivers SS, Fonseca RG, McGivney BA, Govindarajan P, Orr N, Katz LM, MacHugh DE.Variants of the MSTN gene encoding myostatin are associated with muscle hypertrophy phenotypes in a range of mammalian species, most notably cattle, dogs, mice, and humans. Using a sample of registered Thoroughbred horses (n = 148), we have identified a novel MSTN sequence polymorphism that is strongly associated (g.66493737C>T, P = 4.85x10(-8)) with best race distance among elite racehorses (n = 79). This observation was independently validated (P = 1.91x10(-6)) in a resampled group of Thoroughbreds (n = 62) and in a cohort of Thoroughbreds (n = 37, P = 0.0047) produced by the same trainer...
Weese JS, Archambault M, Willey BM, Hearn P, Kreiswirth BN, Said-Salim B, McGeer A, Likhoshvay Y, Prescott JF, Low DE.Methicillin-resistant Staphylococcus aureus (MRSA) infection was identified in 2 horses treated at a veterinary hospital in 2000, prompting a study of colonization rates of horses and associated persons. Seventy-nine horses and 27 persons colonized or infected with MRSA were identified from October 2000 to November 2002; most isolations occurred in a 3-month period in 2002. Twenty-seven (34%) of the equine isolates were from the veterinary hospital, while 41 (51%) were from 1 thoroughbred farm in Ontario. Seventeen (63%) of 27 human isolates were from the veterinary hospital, and 8 (30%) were ...
Metzger J, Karwath M, Tonda R, Beltran S, u00c1gueda L, Gut M, Gut IG, Distl O.Modern horses represent heterogeneous populations specifically selected for appearance and performance. Genomic regions under high selective pressure show characteristic runs of homozygosity (ROH) which represent a low genetic diversity. This study aims at detecting the number and functional distribution of ROHs in different horse populations using next generation sequencing data. Methods: Next generation sequencing was performed for two Sorraia, one Dülmen Horse, one Arabian, one Saxon-Thuringian Heavy Warmblood, one Thoroughbred and four Hanoverian. After quality control reads were mapped t...
Hill EW, McGivney BA, Gu J, Whiston R, Machugh DE.Thoroughbred horses have been selected for traits contributing to speed and stamina for centuries. It is widely recognized that inherited variation in physical and physiological characteristics is responsible for variation in individual aptitude for race distance, and that muscle phenotypes in particular are important. Results: A genome-wide SNP-association study for optimum racing distance was performed using the EquineSNP50 Bead Chip genotyping array in a cohort of n = 118 elite Thoroughbred racehorses divergent for race distance aptitude. In a cohort-based association test we evaluated geno...
Pacini S, Spinabella S, Trombi L, Fazzi R, Galimberti S, Dini F, Carlucci F, Petrini M.It has been proven that mesenchymal stromal cells (MSCs) can differentiate into tenocytes. Attempts to repair tendon lesions have been performed, mainly using scaffold carriers in experimental settings. In this article, we describe the clinical use of undifferentiated MSCs in racehorses. Significant clinical recovery was achieved in 9 of 11 horses evaluated using ultrasound analysis and their ability to return to racing. Our results show that the suspension of a small number of undifferentiated MSCs may be sufficient to repair damaged tendons without the use of scaffold support. Ultrasound sca...
Gu J, Orr N, Park SD, Katz LM, Sulimova G, MacHugh DE, Hill EW.Thoroughbred horses have been selected for exceptional racing performance resulting in system-wide structural and functional adaptations contributing to elite athletic phenotypes. Because selection has been recent and intense in a closed population that stems from a small number of founder animals Thoroughbreds represent a unique population within which to identify genomic contributions to exercise-related traits. Employing a population genetics-based hitchhiking mapping approach we performed a genome scan using 394 autosomal and X chromosome microsatellite loci and identified positively selec...
Vidal MA, Robinson SO, Lopez MJ, Paulsen DB, Borkhsenious O, Johnson JR, Moore RM, Gimble JM.To compare the chondrogenic potential of adult equine mesenchymal stem cells derived from bone marrow (MSCs) or adipose tissue (ASCs). Methods: In vitro experimental study. Methods: Adult Thoroughbred horses (n=11). Methods: BM (5 horses; mean [+/-SD] age, 4+/-1.4 years) or adipose tissue (6 horses; mean age, 3.5+/-1.1 years) samples were obtained. Cryopreserved MSCs and ASCs were used for pellet cultures in stromal medium (C) or induced into chondrogenesis+/-transforming growth factor-3 (TGFbeta(3)) and bone morphogenic factor-6 (BMP-6). Pellets harvested after 3, 7, 14, and 21 days were exam...
Carter CA, Jolly DG, Worden CE, Hendren DG, Kane CJ.Nonhealing wounds of the lower equine limb represent a challenging model. The platelet is a natural source of a myriad of growth factors and cytokines that promote wound healing. This study evaluates the potential of platelet derived factors to enhance wound healing in the lower equine limb. Platelets were isolated from horse blood and activated with thrombin, a process known to induce growth factor release. This produced a platelet gel composed of platelet-rich plasma (PRP). To test this all-natural wound healant, 2.5-cm(2) full thickness cutaneous wounds were created below the knee and hock ...
Corbin LJ, Blott SC, Swinburne JE, Vaudin M, Bishop SC, Woolliams JA.Many genomic methodologies rely on the presence and extent of linkage disequilibrium (LD) between markers and genetic variants underlying traits of interest, but the extent of LD in the horse has yet to be comprehensively characterized. In this study, we evaluate the extent and decay of LD in a sample of 817 Thoroughbreds. Horses were genotyped for over 50,000 single nucleotide polymorphism (SNP) markers across the genome, with 34,848 autosomal SNPs used in the final analysis. Linkage disequilibrium, as measured by the squared correlation coefficient (r(2)), was found to be relatively high bet...
Kasashima Y, Takahashi T, Smith RK, Goodship AE, Kuwano A, Ueno T, Hirano S.Overstrain injuries to the superficial digital flexor tendon (SDFT) and suspensory ligament (SI) are among the most common musculoskeletal injuries which contribute to the considerable wastage of racing Thoroughbreds. Many epidemiological studies have demonstrated the prevalence of and risk factors for tendon injury when racing but have not included those injuries sustained during training. However, since tendon injury during training is seen commonly in clinical practice, it is appropriate to determine the overall prevalence of tendon injury sustained during both training and racing. Objectiv...
Cunningham EP, Dooley JJ, Splan RK, Bradley DG.The thoroughbred (TB) horse is one of the oldest breeds of domestic animals, with pedigree records spanning three centuries. Because the population is essentially closed, there is concern about loss of genetic variation. Here we report two parallel analyses. In the first, genetic variation in the current population is measured using data from 13 microsatellite loci in 211 horses with relationships calculated based on allele sharing. In the second analysis, pedigree information is used to calculate genetic relationships between animals based on shared ancestry. These two measures of relationshi...
Rossdale PD, Hopes R, Digby NJ, offord K.An epidemiological study of wastage among racehorses was conducted in 1982 and 1983 among six stables, five of which were in Newmarket. The basis of the survey was the inability of horses to take part in cantering exercise as a result of injury or disease. The greatest number of days lost to training was caused by lameness (67.6 per cent) and respiratory problems (20.5 per cent). Conditions of the foot (19 pe cent), muscle (18 per cent), carpus (14 per cent), fetlock joints (14 per cent), tendons (10 per cent) and sore shins (9 per cent) were the major reasons for training days being lost in 1...
Watts AE, Yeager AE, Kopyov OV, Nixon AJ.Tendon injury is a common problem in athletes, with poor tissue regeneration and a high rate of re-injury. Stem cell therapy is an attractive treatment modality as it may induce tissue regeneration rather than tissue repair. Currently, there are no reports on the use of pluripotent cells in a large animal tendon model in vivo. We report the use of intra-lesional injection of male, fetal derived embryonic-like stem cells (fdESC) that express Oct-4, Nanog, SSEA4, Tra 1-60, Tra 1-81 and telomerase. Methods: Tendon injury was induced using a collagenase gel-physical defect model in the mid-metacar...
McGreevy PD, Cripps PJ, French NP, Green LE, Nicol CJ.A greater knowledge of the effect of management factors is required to investigate the ontogeny of abnormal behaviour in the stabled horse. A postal survey of racehorse (flat) trainers yielded information about 22 yard and management factors. The relationship of the factors to the prevalence of abnormal behaviour was analysed by logistic regression. Management factors related to the time spent in the stable showed the strongest associations with stereotypic behaviour. The risk of horses performing abnormal behaviour increased: 1) as the amount of forage fell below 6.8 kg/day, 2) when bedding t...
Wallner B, Vogl C, Shukla P, Burgstaller JP, Druml T, Brem G.The paternally inherited Y chromosome displays the population genetic history of males. While modern domestic horses (Equus caballus) exhibit abundant diversity within maternally inherited mitochondrial DNA, no significant Y-chromosomal sequence diversity has been detected. We used high throughput sequencing technology to identify the first polymorphic Y-chromosomal markers useful for tracing paternal lines. The nucleotide variability of the modern horse Y chromosome is extremely low, resulting in six haplotypes (HT), all clearly distinct from the Przewalski horse (E. przewalskii). The most wi...
West JB, Mathieu-Costello O, Jones JH, Birks EK, Logemann RB, Pascoe JR, Tyler WS.Bleeding into the lungs in thoroughbreds is extremely common; there is evidence that it occurs in essentially all horses in training. However, the mechanism is unknown. We tested the hypothesis that exercise-induced pulmonary hemorrhage (EIPH) is caused by stress failure of pulmonary capillaries. Three thoroughbreds with known EIPH were galloped on a treadmill, and after the horses were killed with intravenous barbiturate the lungs were removed, inflated, and fixed for electron microscopy. Ultrastructural studies showed evidence of stress failure of pulmonary capillaries, including disruptions...
Park KD, Park J, Ko J, Kim BC, Kim HS, Ahn K, Do KT, Choi H, Kim HM, Song S, Lee S, Jho S, Kong HS, Yang YM, Jhun BH, Kim C, Kim TH, Hwang S, Bhak J....Thoroughbred horses are the most expensive domestic animals, and their running ability and knowledge about their muscle-related diseases are important in animal genetics. While the horse reference genome is available, there has been no large-scale functional annotation of the genome using expressed genes derived from transcriptomes. Results: We present a large-scale analysis of whole transcriptome data. We sequenced the whole mRNA from the blood and muscle tissues of six thoroughbred horses before and after exercise. By comparing current genome annotations, we identified 32,361 unigene cluster...
Ghosh S, Qu Z, Das PJ, Fang E, Juras R, Cothran EG, McDonell S, Kenney DG, Lear TL, Adelson DL, Chowdhary BP, Raudsepp T.We constructed a 400K WG tiling oligoarray for the horse and applied it for the discovery of copy number variations (CNVs) in 38 normal horses of 16 diverse breeds, and the Przewalski horse. Probes on the array represented 18,763 autosomal and X-linked genes, and intergenic, sub-telomeric and chrY sequences. We identified 258 CNV regions (CNVRs) across all autosomes, chrX and chrUn, but not in chrY. CNVs comprised 1.3% of the horse genome with chr12 being most enriched. American Miniature horses had the highest and American Quarter Horses the lowest number of CNVs in relation to Thoroughbred r...
Newton JR, Daly JM, Spencer L, Mumford JA.Between March and May 2003, equine influenza virus infection was confirmed as the cause of clinical respiratory disease among both vaccinated and unvaccinated horses of different breeds and types in at least 12 locations in the UK. In the largest outbreak, 21 thoroughbred training yards in Newmarket, with more than 1300 racehorses, were affected, with the horses showing signs of coughing and nasal discharge during a period of nine weeks. Many of the infected horses had been vaccinated during the previous three months with a vaccine that contained representatives from both the European (A/eq/Ne...
Tinker MK, White NA, Lessard P, Thatcher CD, Pelzer KD, Davis B, Carmel DK.A prospective study of one year was conducted on 31 horse farms to obtain population based estimates of incidence, morbidity and mortality rates of equine colic. Farms with greater than 20 horses were enrolled by randomly selecting horse owners from 2 adjacent counties of Virginia and Maryland. Descriptive information for 1427 horses was collected at the initiation of the study and updated at 3 month intervals. Time on the farm during the study was tabulated for each horse. When colic was reported by the owner, investigators visited the farm to obtain information about the colic. The crude inc...
Harris RC, Marlin DJ, Dunnett M, Snow DH, Hultman E.1. Muscle buffering capacity (beta m) and dipeptide content were measured in locomotory muscles of the Thoroughbred horse, Greyhound dog and Man. 2. Beta m and carnosine contents were highest in the horse. Anserine was only found in dog muscle. 3. The higher beta m in horse and dog muscle, compared with man, appears to be predominantly due to higher muscle contents of histidine containing dipeptides in these species.
Gibb Z, Lambourne SR, Aitken RJ.The relationship between stallion fertility and oxidative stress remains poorly understood. The purpose of this study was to identify criteria for thoroughbred fertility assessment by performing a logistical regression analysis using "dismount" sperm parameters as predictors and weekly per-cycle conception rate as the dependent variable. Paradoxically, positive relationships between fertility and oxidative stress were revealed, such that samples that produced pregnancies exhibited higher rates of 8-hydroxy-2'-deoxyguanosine release (1490.2% vs. 705.5 pg/ml/24 h) and lower vitality (60.5% vs. 6...
Yamanaka T, Niwa H, Tsujimura K, Kondo T, Matsumura T.On August 2007, we encountered equine influenza epidemic by Florida sub-lineage strain (H3N8) in Japan Racing Association's facilities where 4142 racehorses in total were stabled. The number of new febrile cases sharply increased, but the occurrence was rapidly calmed down within 2 weeks. The morbidity rate in these facilities was 12.8% and the subclinical infection rate of healthy racehorses examined by rapid antigen detection tests was 19.4% at the early stage of epidemic. The serological studies along with the low morbidity rate and the existence of numbers of asymptomatically infected race...
Wallner B, Palmieri N, Vogl C, Rigler D, Bozlak E, Druml T, Jagannathan V, Leeb T, Fries R, Tetens J, Thaller G, Metzger J, Distl O, Lindgren G....The Y chromosome directly reflects male genealogies, but the extremely low Y chromosome sequence diversity in horses has prevented the reconstruction of stallion genealogies [1, 2]. Here, we resolve the first Y chromosome genealogy of modern horses by screening 1.46 Mb of the male-specific region of the Y chromosome (MSY) in 52 horses from 21 breeds. Based on highly accurate pedigree data, we estimated the de novo mutation rate of the horse MSY and showed that various modern horse Y chromosome lineages split much later than the domestication of the species. Apart from few private northern Euro...