Thoroughbreds are a breed of horse known for their agility, speed, and spirit, often associated with horse racing and equestrian sports. Originating from crossbreeding native English mares with imported Arabian, Barb, and Turkoman stallions, Thoroughbreds have a well-documented pedigree that traces back to the late 17th and early 18th centuries. This breed is characterized by a refined head, deep chest, and long legs, contributing to their athletic capabilities. Thoroughbreds are primarily bred for their performance in racing but are also utilized in other equestrian disciplines. This page compiles peer-reviewed research studies and scholarly articles that explore the genetics, physiology, and performance characteristics of Thoroughbreds, as well as their management and welfare in various equine activities.
Keenan DM.Changes in concentration of a number of blood metabolites in 30 thoroughbred horses were recorded after an 1110 metre race. No significant changes occurred in blood urea or aspartate aminotransferase during the three hours after racing. Plasma sodium, potassium and calcium levels were increased immediately after racing but had returned to normal one hour after racing. Plasma phosphate showed a significant fall in concentration one hour after racing. Creatinine and lactic acid concentrations were elevated ten minutes after racing and although they subsequently decreased, the level of lactic aci...
Smyth GB.An abnormal cryptorchid testicle removed from the abdominal cavity of a 4 year old Thoroughbred stallion is described. The abnormal organ conforms to the requirements of Willis (1960) for a teratoma. The difference between these tumours in man and horses is discussed.
Blackmore DJ, Willett K, Agness D.Selenium and gamma-glutamyl transferase activity has been measured in the serum of clinically health thoroughbreds. The thoroughbreds, whose performance was reported to be unsatisfactory, had consistently low concentrations of selenium and high activity of gamma-glutamyl transferase in the serum when compared with those whose performance was as expected. Vitamin E levels in the serum showed no such difference. The only other biochemical and haematological abnormality was lower serum phosphate concentrations in the unsatisfactory group. These results suggest that low concentrations of selenium ...
Rose RJ, Backhouse W, Chan W.Changes in plasma sodium, potassium, chloride, total carbon dioxide, urea, creatinine, glucose, total bilirubin, iron, total protein, albumin, alkaline phosphatase (AP), aspartate amino transferase (AST), calcium, inorganic phosphorus, cholesterol and triglycerides were studied in 45 Thoroughbred foals 15 min to 28 days after birth. The results were analysed in 3 groups; Group 1 (0--12 h), Group 2 (12--36 h), Group 3 (1--4 weeks). When Group 2 was compared to Group 1, there were significant reductions of sodium, creatinine, iron and calcium and elevations of total protein and bilirubin. When G...
Sato T, Oda K, Kubo M.Hematological and biochemical parameters in five Thoroughbred foals during the first six months of life are reported. The samples were analyzed for red blood cell, packed cell volume, hemoglobin, platelet, white blood cell, absolute number for leukocytes, and erythrocyte fragility and serum calcium, inorganic phosphorus, sodium, potassium, chloride, magnesium, alkaline phosphatase, icterus index unit, bilirubin, blood urea nitrogen, nonprotein nitrogen, blood glucose, lacticdehydrogenase, glutamic pyruvic transaminase, glutamic oxalacetic transaminase, total protein, albumin, globulin, and A/G...
Mason TA.Two cases of bilateral atresia of the nasolacrimal orifice are described. The presenting sign was a persistent ocular discharge, clear in the one case and purulent in the other. Treatment by the creation of a fistula between the distal extremity of the blind ending duct and the nasal cavity was successful in both cases.
Peaker M, Rossdale PD, Forsyth IA, Falk M.Small samples of mammary secretion were taken for analysis from Thoroughbred mares during the last 3 weeks of pregnancy up to the time of foaling. The concentrations of sodium and chloride decreased while those of lactose, potassium, citrate, phosphate, calcium, magnesium and protein increased. The time-course of these changes showed marked variation between animals. The concentration of whey proteins began to increase about 10 days before parturition. The appearance of the secretion and the size of the mammary glands increased in the last few days of pregnancy. It is suggested that the concen...
Ellis DR.Eighteen cases of fractures of the proximal sesamoid bones in Thoroughbred foals are described. Most of the fractures were in foals under 2 months old and all but one occurred in the forelegs. The bones commonly fractured when the foal galloped to exhaustion trying to keep up with its dam in the paddock. The types of fracture varied but a simple fracture of the medial sesamoid was most frequent and the majority were towards the base of the bone. Six foals sustained a fracture of more than one sesamoid bone and one foal fractured all 4 proximal sesamoid bones in its front legs. Treatment includ...
Butterfield RM, Matthews RG.Data from 937 Thoroughbred mares, when analysed as a single population, showed no significant difference between the activity of the right and left ovaries and the frequency of location of 35-day pregnancies in the right and left uterine horns. Nor were any differences shown when the data were analysed in years or sire groups. However, significantly more ovulations occurred in the right ovary in September and December and in the left ovary in October and November. Whereas the left and right ovulations were equal in lactating and dry mares, there was a highly significant increase in the number ...
Pope AM, Campbell DL, Davidson JP.Foal heat was significantly delayed in 15 Thoroughbred and Quarter-horse mares by 200 mg progesterone in oil from Days 5--14 post partum. Nine of these mares subsequently received daily i.v. injections of 2 mg of a synthetic GnRH preparation (AY-24,031) from Day 2 of the progesterone-delayed oestrus but this treatment did not significantly shorten oestrus or hasten ovulation. Uterine biopsies taken on Day 15 post partum from all the mares showed a mixed endometrial morphology having both oestrous and dioestrous characteristics. There was an increased proliferation of endometrial glands in thes...
Gunn HM.Histochemical profiles of individual muscle fibres were established using myosin adenosine triphosphatase (myosin ATPase), succinate dehydrogenase (SDHase), and glycogen phosphorylase (GPase) reactions in three muscles (semitendinosus, diaphragm, and pectoralis transversus) of the horse and dog. The major histochemical difference between fibres lies in their myosin ATPase activity; fibres can be subdivided into those with a high and those with a low activity. In horse muscle, all fibres have a high activity of GPase. In the diaphragm and pectoralis transversus, all fibres have a high SDHase ac...
Blackmore DJ, Greenwood RE, Johnson C.During an investigation of a group of clinically well thoroughbreds housed in the same stable, it was noted that seven of the 14 had no detectable thyroxine in the plasma (less than 5 nmol/litre). An investigation of thoroughbreds in this stable over a five month period suggested that the thyroids were functioning normally and that the thyroxine was excreted in the urine. Thyroxine binding studies on the blood of these horses suggested that the major part of the circulating thyroxine was bound to albumin. The thyroxine had been displaced resulting in an apparent absence of plasma thyroxine sin...
Powell DG, David JS, Frank CJ.This report contains details of the code of practice for the control of contagious equine metritis (CEM) during the 1979 breeding season. It was prepared under the guidance of a scientific committee established by the Horserace Betting Levy Board under the chairmanship of Sir David Evans, FRS. The code is similar to the one introduced for the 1978 breeding season but takes into account the experience gained during the past 12 months. Following discussions with colleagues in Ireland it has been agreed that a similar code of practice will be introduced in the United Kingdom and Ireland so as to ...
Gunn HM.The mean fibre areas of samples from m. semitendinosus, m. diaphragma and m. pectoralis transversus of thoroughbred horses and greyhounds have been compared with those in similar samples from other members of their species. Athletes (greyhounds and thoroughbreds) have larger fibres in the semitendinosus and diaphragm than their fellows. However, the mean area of pectoralis transversus is similar in the two types of animal within each species. During growth the mean fibre areas increase to a greater extent in athletes than in non-athletes. Detraining adult greyhounds for a period of one year di...
Allen BV.The assay of serum folate has been used to investigate the folate status of thoroughbreds in training to race, in-foal thoroughbred mares at stud and crossbred ponies kept permanently at grass. Throughbreds in training, with no obvious haematological or clinical abnormalities, had lower serum folate levels (mean 3.3, range 1.5 to 6.1 microgram per litre) compared with thoroughbred mares at stud (mean 10.6, range 6.4 to 15.8 microgram per litre) and crossbred ponies at grass (mean 10.9, range 7.4 to 16.6 microgram per litre. Intensive exercise, over a period of six months, significantly decreas...
Barnes RJ, Comline RS, Jeffcott LB, Mitchell MD, Rossdale PD, Silver M.The concentrations of 13, 14-dihydro-15-oxo-prostaglandin F(PGFM), the stable metabolite of prostaglandin F, were measured in the plasma of catheterized mares and foetuses and non-catheterized thoroughbred mares and ponies during the last months of gestation. The plasma concentration of PGFM increased gradually towards term in all groups of animals. During the operation for insertion of catheters, maternal and foetal concentrations of PGFM were high, but the values fell to basal levels 24--48 h after the operation. It was found the preoperative starvation (24 h) led to a rise in the concentrat...
Littlejohn A, Blackmore DJ.The occasions, position and relative concentration of LDH iso-enzymes in the blood tissues of the thoroughbred horse were determined. Locomotor muscles possess a high concentration of LDH 5 whereas non-locomotor muscles have a low concentration of this iso-enzyme.
Digby NJ.Experimental studies of endometrial smears from 26 normal mares showed that after a period of sexual rest exceeding 7 days smears were generally free from inflammatory cells. Smears from 9 mares showing signs of persistent endometritis contained inflammatory cells in 91 per cent while bacterial culture was positive in only 45 per cent. Smears were also taken from 242 Thoroughbred mares as a routine procedure in 1977. It was concluded that endometrial cytology provides a better guide to uterine inflammation than bacteriology. The routine clinical use of endometrial cytology is recommended to ai...
Murray DR, Ladds PW, Johnson RH, Pott BW.Extensive subcutaneous phycomycosis of the lower hindlimb developed over a period of 8 months in a Thoroughbred filly. There was no response to treatments such as trichlorphon, sodium iodide, or etisazole. Extension of the limb lesion over the following 3 months was associated with an enlarged inguinal lymph node, which was removed. Characteristic phycomycotic lesions were observed in the node, and a fungus having the morphologic features of Hyphomyces destruens was isolated from both the limb and nodal lesions.
Jondorf WR, Moss MS.1. Cross-bred and thoroughbred geldings were injected with veterinary doses of various synthetic anabolic steroids. Urines collected sequentially from treated animals were analysed, following solvent extraction, by radioimmunoassay using 19-[3H]nortestosterone and an antibody raised against a 19-nortestosterone immunogen. 2. Urinary excretion of 19-nortestosterone and/or its cross-reacting metabolites was detectable for various times after administration of different nortestosterone esters, as follows: phenylpropionate (400 mg), greater than 14 days; cyclohexylpropionate (100 mg), greather tha...
Weitkamp LR.Polymorphism of equine Gc protein was demonstrated by immunofixation electrophoresis with a goat anti-human Gc antibody. Three different phenotypes, F, FS and S, were found. Family data supported the genetic theory of two autosomal codominant alleles, GcF and GcS. Both alleles occurred in Standardbred, Thoroughbred and Arabian horses and in Shetland ponies. A frequency of 0.23 for GcS in the American Standardbred horse indicates the system should be useful for problems of identification and parentage.
Strömberg B, Rejnö S.The clinical and radiologic features of osteochondritis dissecans in the knee and hock joint of horses are described. The material includes 91 horses, of which 43 had the lesion in one or both knee joints, and 48 in one or both hock joints. It was found that osteochondritis dissecans of the knee joint was more common than the one in the hock joint in thoroughbreds and halfbreds, while the lesion in the hock joint was most common in standardbred trotters. In the knee the lesion was most often located to the lateral trochlear ridge. In the hock joint the predilection site was the intermediate ri...
Kavazis AN, Kivipelto J, Choe HS, Colahan PT, Ott EA.The objective of this study was to investigate the effects of ribose supplementation on blood ammonia-N, plasma lactic acid, plasma glucose, volume of oxygen consumption (VO2), heart rate, and performance in Thoroughbred geldings performing a maximal treadmill standardized exercise test (SET). The hypothesis tested was that ribose supplementation would decrease ammonia-N and lactic acid accumulation during exercise, and improve performance. Eight Thoroughbred geldings were assigned randomly to one of two groups: glucose or ribose. The glucose group received 0.15 g glucose/kg of BW, and the rib...
Kamm JL, Bramlage LR, Schnabel LV, Ruggles AJ, Embertson RM, Hopper SA.Analysis was performed to examine a method for refining the preoperative prognosis for horses that had surgery to remove apical fractures of the proximal sesamoid bones (PSBs). Objective: To determine if: 1) there was a difference in size or configuration of apical fractures between the different anatomical locations of the PSBs, which have been shown to affect the prognosis; and 2) the size or configuration could predict the prognosis for racehorses with these fractures. Methods: The study included 110 weanlings and yearlings and 56 training racehorses that underwent surgery to remove apical ...
Oikawa M.The dorsocaudal extremities of the caudal lobes of the lungs of racehorses are vulnerable to exercise-induced pulmonary haemorrhage (EIPH). The morphology of the lungs at these sites was studied in 13 Thoroughbred horses aged 18 to 22 months. These animals, which had been performing low-intensity exercise on a track at maximum running speeds of approximately 5-8.5 metres/second (m/s), were withdrawn from the racehorse training programme for reasons of unsuitability. Lung lesions observed in the dorsocaudal lung extremities in 10 of the 13 horses were not found in the craniodorsal or craniovent...
Zebarth BJ, Sheard RW.The 2 dominant processes involved in the horse hoof-to-racing surface interaction are the shock loading of the horse's leg upon impact with the racing surface and rotation of the horse's hoof into the racing surface. These processes were measured as impact resistance (ie, the peak deceleration of a moving body upon impact with the test surface) and as resistance to shear. The objective of the present study was to measure physically (under a variety of conditions) those soil and turf factors related to the 2 processes. It was concluded that thatch accumulation and mowing height of the turf did ...
Yokomori T, Tozaki T, Mita H, Miyake T, Kakoi H, Kobayashi Y, Kusano K, Itou T.According to oral traditions of horse caretakers and trainers, the differences in the position and number of facial hair whorls may be associated with temperamental traits. Elucidating genetic background of facial hair whorls and its relationship to temperamental traits may promote more efficient breeding and maintenance of racehorses. In this study, we estimated heritabilities of the position and number of facial hair whorls in Japanese Thoroughbred horses. Results: The number of facial hair whorls varied from one to four and heritability estimate in 4024 Thoroughbred horses was low (h2= 0....
Williams CA, Kronfeld DS, Staniar WB, Harris PA.Plasma concentrations of glucose and insulin following a meal were compared in twelve Thoroughbred mares fed a pelleted concentrate (PC), a traditional sweet feed high in sugar and starch (SS), or a feed high in fat and fiber (FF). The feeds had similar DE and CP but differed in fat (19, 32, and 166 g/kg DM, respectively), NDF (199, 185, and 369 g/kg DM, respectively) and nonstructural carbohydrates (574, 645, and 247 g/kg, respectively). Mares were randomly assigned to two groups balanced for foaling date and weight. All mares received PC in late gestation; then, after foaling, one group was ...
Ordakowski-Burk AL, Kronfeld DS, Williams CA, Gay LS, Sklan DJ.To identify changes in folate status of mares and foals during lactation and growth, respectively. Methods: 20 Thoroughbred mares and foals. Methods: Pregnant mares, and following foaling the same mares with their foals, were maintained on mixed grass-legume pasture and fed either a traditional dietary supplement rich in sugar and starch (SS) or a dietary supplement high in fat and fiber (FF). Blood samples were collected monthly from mares and foals up to 6 months after foaling. Total folate concentration in feed and forage was determined. Analyses of plasma folate, RBC folate, plasma homocys...
Swinburne JE, Hopkins A, Binns MM.The dominant grey coat colour gene of horses has been mapped using a whole genome scanning approach. Samples from a large half-sibling pedigree of Thoroughbred horses were utilized in order to map the grey coat colour locus, G. Multiplex groups of microsatellite markers were developed and used to efficiently screen the horse genome at a resolution of approximately 22 cM, based on an estimated map length for the horse genome of 2720 cM. The grey gene was assigned to chromosome 25 (ECA25), one of the smaller acrocentric horse chromosomes. Based on the current state of knowledge of conserved synt...
Stirk SA.A 5 year old Thoroughbred stallion with diarrhoea of unknown aetiology was referred to Davis. Treatment was aimed at terminating diarrhoea and restoring normal fluid status. Laboratory aids were utilised to establish where inbalance and deficits were present. Antibiotics and corticosteroids were used as an adjunct to fluid therapy. The case history and rationale of treatment of fluid disorders resulting from diarrhoea are discussed.
Latif SN, Von Peinen K, Wiestner T, Bitschnau C, Renk B, Weishaupt MA.To a large extent the success of a racehorse depends on effective and health preserving training methods. An important issue is the prevention of back pain. The influence of different types of training saddles (normal tree: S(A), treeless: S(B), flexible tree: S(C)) on the saddle pressure patterns in racehorses have not previously been investigated. It is commonly assumed that S(A) limits the motion of the back especially in the lower thoracic region during gallop. Objective: S(A) produces higher pressures in the caudal part of the saddle at trot (rising trot), canter and gallop (both in a joc...
Pye J, Spriet M, O'Brion J, Carpenter R, Blea JA, Dowd JP.To assess the repeatability of equine 18F-sodium fluoride (18F-NaF) positron emission tomography (PET) findings, and to evaluate the ability of PET to monitor the progression of areas of increased radiopharmaceutical uptake (IRU) in the fetlocks of Thoroughbred racehorses. Methods: 25 racehorses with clinical signs related to fetlock injuries. Methods: This study is a prospective, longitudinal clinical study. Twenty-five racehorses (54 fetlocks) underwent three 18F-NaF PET scans 6 weeks apart. The first 18F-NaF PET scan was performed at the start of a 12-week period of rest from racing (lay-up...
Campbell TE, Doughty H, Harris PA, de Laat MA, Sillence MN.The rapid intake of high-cereal, low-roughage meals may cause gastrointestinal and behavioral disorders. We investigated some of the factors that can affect the rate of intake (ROI) in four separate studies. Study 1 investigated the effect of chaff length and addition rate on the ROI of oats. The ROI decreased as more chaff was added to the diet, attaining significance (P < .05, n = 6) at levels above 15% addition and reaching a plateau at ∼50%. This was independent of stalk length (1.4 cm vs. 4.1 cm). Study 2 showed that meal size (varying from 0.5 to 4 g/kg BW) did not affect the RO...
Rossier Y, Sweeney CR, Heyer G, Hamir AN.A 7-year-old Thoroughbred mare was examined because of persistent bilateral epistaxis and respiratory distress. Evidence of bilateral pleural effusion was found during physical examination, and a large amount of serosanguineous fluid was drained from the right side of the thorax. Cytologic examination and bacteriologic culture of the transtracheal aspirate and pleural fluid did not yield evidence of sepsis. A coagulation profile was unremarkable. Radiographic and echographic changes were seen in the lung parenchyma. Pleuroscopy, with the horse standing, revealed numerous dark nodules on the pl...
Colahan PT, Bailey JE, Chou CC, Johnson M, Rice BL, Jones GL, Cheeks JP.Twelve clinically sound, healthy, athletically conditioned Thoroughbred horses were subjected to an incremental exercise stress test to determine the effects and period of detection of a single dose of flunixin meglumine (1.1 mg/kg by intravenous injection) in serum and urine by ELISA. Flunixin concentrations, performance, and hematologic and clinical chemical parameters were measured. All horses were rotated through four treatment groups of a Latin-square design providing for each horse to serve as its own control. Flunixin meglumine reduced prostaglandin F(1alpha) and thromboxane concentrati...
Sato F, Otsuka N, Kuwano A.The shape of the white line of the hoof is closely related to the shape of the notch on the dorsal distal bearing border of the distal phalanx (P3). In this study, a radiographic survey of the P3 of both forelimbs of 163 Thoroughbred yearling horses was conducted. The correlation of the depth and width of the notch were analyzed with the toe white line separation grades (0 to 3). As a result, the toe white line separation grade increased, the depth and the width of the notch also increased significantly. Radiographic examination of the P3 of the forelimbs might be useful for deciding whether t...
Asano R, Suzuki K, Otsuka T, Otsuka M, Sakurai H.Concentrations of trace elements (As, Al, Pb, Cd, Hg, Se, Si, P, Na, K, Ca, Mg, Fe, Cu, Zn, Mn, Cr, Ni and Mn) in the mane hair obtained from 9 female and 15 male healthy racing Thoroughbred horses aged 2-5 years were analyzed by the inductively coupled plasma atomic emission spectrometry (ICP-AES) method. No significant differences between the female and male horses were observed in the mean concentrations of those minerals. Significantly positive correlations with age were observed in Cd (r=0.546, p<0.01) and Mo (r=0.733, p<0.001). Significantly negative correlations with age were observed i...
Pedler C, Nath L, Agne GF, Hebart M, Franklin S.Atrial fibrillation (AF) is the most common performance-limiting arrhythmia of racehorses. A genetic contribution has been suggested in Standardbred racehorses but has not been investigated in Thoroughbreds. The objective of this study was to determine the heritability of AF in Thoroughbred racehorses. Methods: Horses racing between 2007 and 2019 in Hong Kong and Australia that had AF detected postrace via auscultation (n = 463 cases) were compared with five randomly selected racing contemporaries (n = 2,315 controls). The ASReml-R programme was used to fit an animal model to the AF data t...
Newton JR, Wood JL, Chanter N.A matched case control study was used to determine infections and other factors associated with clinically apparent respiratory disease in young racehorses in training in the UK. A total of 170 cases, defined as horses with sudden onset coughing, nasal discharge or pyrexia, were identified and matched to 632 non-affected controls by trainer and time period. Factors examined included age, sex, time since entry into the training yard, time since last race and different infections including tracheal and nasopharyngeal (NP) bacteria and viruses. Multivariable conditional logistic regression (CLR) ...
Dahl VE, Hitchens PL, Stover SM.OBJECTIVE To determine the effects of racetrack surface and shoe characteristics on formation of wear grooves in the horseshoes of racehorses. SAMPLES 1,121 horseshoes from 242 Thoroughbred racehorses collected during routine horseshoeing procedures at 4 racetracks with dirt or synthetic surfaces. PROCEDURES Data for 1,014 horseshoes from 233 racehorses were analyzed. Horseshoes were photographed, and length and width of grooves formed at the heels of the solar surface of horseshoes were measured on the photographs. Effects of racetrack, racetrack surface, and shoe characteristics (eg, shoe si...
Kuhnke S, König von Borstel U.The present study aimed to assess an agreement between established and novel methods to determine laterality and to identify the distribution of laterality in warmbloods and Thoroughbreds. Nine different methods to investigate a horses' laterality outside a riding context and during riding were compared across two groups of horses (sample A: 67 warmblood- type horses, sample B: 61 Thoroughbreds). Agreement between any two methods was assessed by calculating Cohen's kappa with McNemar's test or Bowker's Test of Symmetry, and the deviation from equal distributions was assessed with chi2-tests. C...
Scilimati N, Pepe M, Pressanto MC, Angeli G, Beccati F.A 4-month-old Thoroughbred filly was referred for evaluation of severe left forelimb lameness of 24 hours duration. Radiographic projections of the shoulder revealed mild irregularity and sclerosis of the proximal humeral apophysis. Ultrasonographic examination showed a moderate increase in the amount of anechogenic synovial fluid within the intertubercular bursa and scapulohumeral joint, and irregularity of the ossifying bone surface of the intermediate tubercle of the humerus. Computed tomographic (CT) examination revealed a circular hypoattenuating area at the level of the proximal apophysi...
Woodward MC, Huff NK, Garza F, Keowen ML, Kearney MT, Andrews FM.The objectives of this study were to evaluate the effects of two commercial feed supplements, Egusin 250® [E-250] and Egusin SLH® [E-SLH], on gastric ulcer scores, gastric fluid pH, and blood gas values in stall-confined horses undergoing feed-deprivation. Methods: Nine Thoroughbred horses were used in a three-period crossover study. For the three treatment groups, sweet feed was mixed with E-250, E-SLH, or nothing (control group) and fed twice daily. Horses were treated for 21 days, then an additional 7 days while on an alternating feed-deprivation model to induce or worsen ulcers (period o...
Reiter S, Wallner B, Brem G, Haring E, Hoelzle L, Stefaniuk-Szmukier M, Długosz B, Piórkowska K, Ropka-Molik K, Malvick J, Penedo MCT, Bellone RR.Warmblood fragile foal syndrome (WFFS) is an autosomal recessive disorder caused by a single nucleotide variant in the procollagen-lysine-2-oxoglutarate-5-dioxygenase 1 gene (PLOD1:c.2032G>A, p.Gly678Arg). Homozygosity for the PLOD1 variant causes an Ehler-Danlos-like syndrome, which has to date only been reported in warmblood breeds but the WFFS allele has been also detected in the Thoroughbred. To investigate the breed distribution of the WFFS allele, 4081 horses belonging to 38 different breeds were screened. In total, 4.9% of the horses representing 21 breeds carried the WFFS allele. The a...
Farries G, Bryan K, McGivney CL, McGettigan PA, Gough KF, Browne JA, MacHugh DE, Katz LM, Hill EW.While over ten thousand genetic loci have been associated with phenotypic traits and inherited diseases in genome-wide association studies, in most cases only a relatively small proportion of the trait heritability is explained and biological mechanisms underpinning these traits have not been clearly identified. Expression quantitative trait loci (eQTL) are subsets of genomic loci shown experimentally to influence gene expression. Since gene expression is one of the primary determinants of phenotype, the identification of eQTL may reveal biologically relevant loci and provide functional links ...
Ramzan PHL, Wylie CE.Arthroscopy has been advocated as the treatment of choice for dorsal osteochondral chip fracture of the metacarpo/metatarsophalangeal (MCP/MTP) joint. However, there is no published research on racing performance outcomes of horses with this pathology managed nonsurgically. Objective: To compare racing career outcomes of Thoroughbred racehorses with nonsurgically (non-SX) or surgically (SX) managed MCP/MTP dorsal osteochondral chip fracture alongside a cohort of horses with no dorsal osteochondral chip fracture (unexposed). Methods: Retrospective cohort study conducted between 2006 and 2014. M...
Hackett ES, Embertson RM, Hopper SA, Woodie JB, Ruggles AJ.Large colon volvulus results in strangulating obstruction requiring surgical treatment. Duration of this disease prior to surgical treatment is likely to influence survival directly. Objective: The primary objective of this study was to evaluate the influence of duration of large colon volvulus on patient survival to discharge. Relationships between other factors and survival following large colon volvulus were also examined. Methods: Retrospective case analysis. Methods: Medical records of Thoroughbred mares aged ≥2 years undergoing surgical treatment for large colon volvulus between 1 Marc...
Kniazev SP, Reissmann M, Wagner HJ, Kuraĭ MV, Samovolov NV.Results of the first in Russia survey of the gene pool of the breeding nucleus of the Russian population of thoroughbred horses by means of PCR analysis of the E (Extension) locus MC1R gene mutations are presented. The data on the structure of breeding populations from the leading stud farms Voskhod and Oros with regard to color phenotypes as well as genotype and allele frequencies are presented. The population structure parameters are discussed with respect to possible specific features of microevolution processes.
Ley WB, Scott Pleasant R, Dunnington EA.Studies evaluating nutritional and seasonal influences on hoof strength and composition in horses, as well as the scientific justification for feeding supplements to improve hoof quality, are lacking. The horseman and veterinarian need controlled studies in this area to make informed decisions. This project quantified, in 2 trials, relative elasticity, tensile strength, % moisture, and mineral composition of hooves of 48 mature Thoroughbred mares maintained on different nutritional/management regimens, sampled quarterly over 12 month periods. Tensile strength was positively associated with sul...
Tennent-Brown BS, Goetz TE, Manohar M, Hassan AS, Freeman DE, Bundy JS, Evans MR.Dehydration and the associated impairment of cardiovascular and thermoregulatory function comprise major veterinary problems in horses performing prolonged exercise, particularly under hot and humid conditions. For these reasons, there is considerable interest in using pre-exercise hyperhydration to help maintain blood volume in the face of the excessive fluid loss associated with sweat production during prolonged exertion. However, recently it was reported that pre-exercise hyperhydration causes arterial hypoxemia in horses performing moderate intensity exercise simulating the second day of a...
Ishikawa S, Horinouchi C, Murata D, Matsuzaki S, Misumi K, Iwamoto Y, Korosue K, Hobo S.Mesenchymal stem cells (MSCs) are adult multipotent stem cells that are capable of self-renewal and differentiation into multiple cell lineages. Methods for cell therapy using MSCs have been developed in equine medicine. Recently, human dental pulp stem cells (DPSCs) have drawn much attention owing to their trophic factor producing ability and minimally invasive collection methods. However, there have been no reports on equine dental pulp-derived cells (eDPCs). Therefore, the aim of this study was to isolate and characterize the eDPCs from discarded wolf teeth. Plastic-adherent spindle-shaped ...
