Statistical analysis in equine research involves the application of mathematical techniques to collect, review, and interpret data related to horse health, behavior, and performance. This field encompasses a variety of methods, including descriptive statistics, inferential statistics, and multivariate analysis, to identify patterns, test hypotheses, and draw conclusions from equine data. Statistical analysis aids in understanding various aspects of equine science, such as disease prevalence, treatment efficacy, genetic traits, and performance metrics. This page aggregates peer-reviewed research studies and scholarly articles that explore the methodologies, applications, and outcomes of statistical analysis in the context of equine studies.
Rudman R, Keiper RR.The summer body condition of 47 adult feral ponies on Assateague Island (off the coast of Maryland, USA) was assessed in June 1988 using a visual body condition scoring system. Winter body condition for 36 of the ponies was assessed in February and March, 1989. The ponies were categorised by gender, reproductive status and location on the island, and body condition scores of the ponies in each category were then compared by statistical analyses. No significant seasonal differences were found in the body conditions of the ponies. However, body condition of stallions was better than that of mare...
Baldwin JL, Cooper WL, Vanderwall DK, Erb HN.Serum samples for determination of IgG concentration were obtained between postpartum hours 18 and 48 from 132 Standardbred foals. Results of the IgG assay were not known to farm personnel. None of the foals was given plasma IV for treatment of hypogammaglobulinemia. Foal health records were examined retrospectively to determine prevalence of infectious-type illness (foal treatment days [FTD]), prevalence of life-threatening infectious illness (foal treatment days-serious condition [FTD-SC]), and number of diseases (NOD) per foal. Values for FTD, FTD-SC, and NOD per foal were compiled for the ...
Wilson DA, Baker GJ, Pijanowski GJ, Boero MJ, Badertscher RR.Suspensory ligaments (SL) from 32 Thoroughbreds and 32 Standardbreds were collected to evaluate the variation in muscle content with respect to age, breed, sex, limb, and use. Six transverse sections, each 3 to 5 mm thick, were obtained from each SL. Four sections were taken from the body of the SL and 1 from the midportion of each branch. Sections were stained with van Gieson picric acid-fuchsin solution, then photographed, and black-and-white slides were made from the processed negatives. The transverse-sectional area of the SL and the contained muscle were determined by use of a computer wi...
Vörös K, Holmes JR, Gibbs C.This study was performed on 15 horses to validate the cardiac anatomy as imaged with two dimensional echocardiography (2DE) and to determine the accuracy of intracardiac measurements. 2DE images were recorded in five horses in life with a Diasonics DRF100 ultrasound system and a 3.5 MHz transducer in different tomographic planes. After slaughter, the hearts were fixed in 10 per cent formalin. To compare in vivo and in vitro results, the specimens were suspended in a water-filled tank and 2DE images were made using the same transducer positions as in life. In vitro 2DE and autopsy measurements ...
Pascoe PJ, Ducharme NG, Ducharme GR, Lumsden JH.In order to determine which variables are useful and accurate in estimating prognosis in horses with abdominal pain, data were analyzed from 231 horses presented at a veterinary teaching hospital. Using multiple stepwise discriminant analysis in a recursive partition model, we obtained a decision protocol that identified survivors and nonsurvivors. The prevalence of survivors was 61% in this population. The sensitivity, specificity, and positive and negative predictive values of this model were 71, 83, 87 and 65%, respectively. This decision protocol was validated by Jackknife classification a...
Lord PF, Croft MA.Echocardiography may be an accurate method of measuring left ventricular (LV) volumes and mass of the horse's heart. If so, studies of the heart size and hypertrophy would be possible. This study evaluated geometric models of the external and internal LV shapes, to determine which could be applied to echocardiographic measurements. We preserved 30 horses' hearts and measured their dimensions and cross sectional areas. These measurements were entered into seven formulae representing different geometric models of the ventricle and its chamber. We derived a correction factor to estimate the long ...
Sweeney CR, Soma LR, Maxson AD, Thompson JE, Holcombe SJ, Spencer PA.The effects of furosemide on the racing times of 79 horses without exercise-induced pulmonary hemorrhage (EIPH) and 52 horses with EIPH were investigated. Racing times were adjusted to 1-mile equivalent racing times by 2 speed handicapping methods, and analysis of covariance was used to adjust actual racing times by winning time and distance for each race. All 3 methods of determining racing time indicated that geldings without EIPH had significantly faster racing times (P less than 0.05) when given furosemide before racing than when furosemide was not given before racing. Females and colts wi...
Loch W, Worthy K, Ireland F.Sixteen non-pregnant pony mares were divided into four groups of similar age and bodyweight (bwt). Groups were randomly assigned to one of four treatments consisting of oral administration of perphenazine (0.5 and 1.0 mg/kg bwt, phenothiazine (10 mg/kg bwt) and a control group. Blood samples were taken by jugular venepuncture and plasma prolactin concentrations measured using an homologous assay for equine prolactin. Analysis of variance was conducted on data designed as a split plot over time. Perphenazine given orally (0.5 and 1.0 mg/kg bwt) increased plasma prolactin concentrations when mea...
López-Rivero JL, Agüera E, RodrÃguez-Barbudo MV, Galisteo AM, Morales-López JL.Samples taken from the middle gluteal muscle of 95 untrained adult horses of different ages and sex were subjected to histochemical analysis using the myosin adenosine triphosphatase (m-ATPase) and nicotinamide adenine dinucleotide tetrazolium reductase (NADH-TR) staining techniques. Fibres were classified into types I, IIA and IIB according to m-ATPase activity after preincubation at pH 4.4. The percentage of FT (Fast-Twitch Glycolytic) fibres and the proportion of IIB fibres with "high" and "low" oxidative capacity were determined in serial sections stained for NADH-TR. Statistical analysis ...
Jones RS, Lawrence TL, Veevers A, Cleave N, Hall J.Fifty-three horses, all but two of them over two years of age and varying in type, sex and liveweight (230 to 707 kg) were weighed and seven different body measurements were recorded in duplicate by a single operator. The best overall prediction of liveweight using an equation with two variables was found to be: liveweight (kg) = (umbilical girth [cm])1.78 X (length of body from tuber ischii to elbow [cm]0.97/3011). This equation had an adjusted R2 value of 94.9 per cent and was derived from the pooled data, because differences of sex, type and weight did not significantly affect the relations...
Copland VS, Hildebrand SV, Hill T, Wong P, Brock N.Blood pressure during anesthesia and surgery was compared for 2 groups of horses. Group A, consisting of 23 horses, had a tourniquet placed on the distal portion of a limb. The other group of 20 horses (group B) had surgery of comparable nature and duration as did group-A horses, but a tourniquet was not used. There was a statistical difference (P less than 0.05) in the peak systolic arterial blood pressure between the groups; group-A horses had a mean (+/- SEM) peak of 151 +/- 6 mm of Hg and group-B horses had a peak of 118 +/- 4 mm of Hg. In addition, group-A horses had immediate decrease in...
Craig AM, Blythe LL, Lassen ED, Rowe KE, Barrington R, Slizeski M.Fluctuations of serum vitamin E (alpha-tocopherol), cholesterol, and total lipids were monitored in 12 horses at 3-hour intervals for 72 hours. Mean coefficients of variation were 12, 5, and 15%, respectively. Statistical analyses were used to conclude that instrumentation error was accountable for only a small portion of the vitamin E variation. Results indicated that a single serum sample assay is an unsatisfactory indicator of vitamin E status in horses. These data have clinical application in the evaluation of horses suspected to be affected with equine degenerative myeloencephalopathy. Th...
Berndtson WE.Data from testes of 16, 2- to 3-yr-old stallions and 34 yearling beef bulls were utilized in a components of variance approach to calculate the number of observations required per testis and(or) the number of animals required per treatment group to provide experiments of known sensitivity and precision, where treatment was to be assessed by one of several endpoints. The latter included paired testes weight, seminiferous tubular diameter, the number of germ cells per seminiferous tubular cross-section, or the number of elongated spermatids per gram of testicular parenchyma or per testis. For al...
Bianchi M.In 13 horses from both sexes, between 5 months and 18 years of age, in good nutritional state, statistical evaluations of fat cell sizes were performed in 16 body regions. From direct and indirect measurements referred to the cell diameter and cell number in equivalent areas, carried out on sections from paraffin embedded material and on preparations of dissociated whole cells, it emerged that the adipose cells of the subserous fat of the abdominal floor are consistently the largest, whereas those of the orbital fat body and supraorbital fossa are the smallest. In the other regions the cells h...
McMurphy RM, Cribb PH.This study was designed to investigate the effect of the nasotracheal insufflation of oxygen at a flow rate of 15 L/min on the arterial partial pressure of oxygen during the recovery period following inhalation anesthesia in the horse. It has been stated that this is a suitable flow rate to prevent postoperative hypoxemia but without any experimental evidence to support those statements. Horses being used for the study of healing of cartilage were anesthetized on two separate occasions. Following one period of anesthesia they were allowed to recover breathing room air, and following the other ...
Irvine CH, Alexander SL.Pituitary venous blood was collected by a painless nonsurgical cannulation method from five ambulatory stallions at 5-min intervals for 5-6 h during the breeding season. In four adult stallions, statistical analysis showed that pulses of gonadotrophin-releasing hormone (GnRH) and LH were coincident (P less than 0.01), as were pulses of FSH and LH (P less than 0.05). Furthermore, the patterns of changes in concentration of FSH and LH were highly correlated in each of the four stallions. However, seemingly ineffective pulses of GnRH were also observed, with 28% of GnRH pulses failing to induce a...
Cribb PH.Forty-five horses were maintained on halothane or isoflurane anesthesia for at least 90 minutes and received positive pressure ventilation after the first 30 minutes of anesthesia. Parameters monitored included end-tidal partial pressure of carbon dioxide (ETPCO2), arterial blood pressure, and arterial blood gases and pH. There was a statistically significant correlation between end-tidal carbon dioxide and arterial partial pressure of carbon dioxide (PaCO2) for both halothane and isoflurane anesthesia. There was no significant correlation between end-tidal carbon dioxide and either body weigh...
Ralston JM, Stenhouse AM, Stenhouse NS, Buck GJ, Lucks SF, Reynoldson JA, Bolton JR.A survey of the concentrations of cortisol in blood and urine samples taken from thoroughbred and standardbred horses after racing is presented. Statistical analysis showed the only significant difference between thoroughbred and standardbred horses was a higher cortisol concentration in thoroughbred urine. Urine volume and pH had no significant influence on the urinary cortisol concentration, however 9.5% of the urinary cortisol variation could be explained due to the influence of plasma cortisol concentration. The results of cortisol and ACTH administrations are also shown and compared with ...
Denny JE.Horses receiving a pelleted or cubed dietary supplementation with roughage, have serum inorganic phosphate (SIP) concentrations consistently below an accepted mean of 1,032 mmol l-1 or 3, 1 mg dl-1. Further, it has been reported that the best eight, two-year-old Irish Thoroughbred track performers of 51 horses tested over a 10 month period, had significantly lower SIP concentrations than the worst eight track performers. In an endeavour to assess any nutritive effect on SIP concentrations and also to assess any effect of SIP concentrations on track performance, metabolic blood profiles from 30...
Leach DH, Sprigings EJ, Laverty WH.Standard univariate and bivariate statistical methods and two multivariate methods, stepwise regression and factor analyses, were used to analyze 17 stride-timing measurements of 22 racing Thoroughbreds filmed at the beginning of races. All horses were in a right-lead transverse gallop. Data were extracted from frame-by-frame analysis of 16-mm film taken with a high-speed camera. The mean stride duration was 0.405 s and the mean stride frequency was 2.47 strides/s. Stride duration had a higher correlation to the suspension-phase duration (r = 0.864) than to stride-stance-phase duration (r = 0....
von Segesser L, Jornod N, Faidutti B.The risk of repeat sternotomy is higher than that of the initial sternotomy, especially if the pericardial sac was left open at the first intervention. In 200 consecutive patients with a pericardial defect after open heart operations, the pericardium was closed with a glutaraldehyde-preserved equine pericardial patch. Precardiac adhesions at reoperation were assessed in four groups of patients on a scale of 6, ranging from 0 (no adhesions) to 5 (calcified or ossified adhesions). Group I comprised 13 patients in whom the pericardium was left open at the first operation and an equine pericardial...
Fuchs R, Militz H, Hoffmann M.The ascertainment of the digestibility of crude nutrients in rations for horses requires the inclusion of movement-based performance as influencing factor. Under the consideration of this requirement, indicator methods gain significance in comparison with the standard method of collecting faeces completely. In two experiments the digestion of the crude nutrients in rations for horses was tested according to the standard method (complete collection of faeces) and the indicator method 4 N HCl-insoluble ash). According to the indicator method the digestibility of crude nutrients was slightly high...
Andersson L, Arnason T, Sandberg K.Investigations on relationships between biochemical polymorphism and variation in quantitative traits are of interest from the perspectives of both theoretical quantitative genetics and practical animal breeding. This subject was studied by using racing performance records of more than 25,000 horses of the Swedish Trotter breed born in the period 1970-1979. For all horses data on six blood group and nine electrophoretic loci were available. Two different performance traits were investigated. A racing performance index value was calculated for all individuals which had started in at least five ...
Pascoe RR, Pascoe DR, Wilson MC.Between 1982 and 1985, 1015 mares were evaluated using the following parameters: age, mare status (maiden, barren, lactating), Caslick index, Caslick operation, ovarian cycle, ovarian and follicular size, treatments (hCG and intrauterine infusions), number of ovulations after mating (184 mares), number of conceptuses present, dimensions of embryonic vesicles, and pregnancy status 45 days after mating. Mares were examined ultrasonographically between Days 12 and 25 to detect the presence of embryonic vesicles and measure the dimensions of each vesicle. The data were analysed by a stepwise logis...
Hodson NP, Wright JA, Hunt J.Plasma levels of adrenocorticotropic hormone (ACTH), cortisol and catecholamines were used to study the role of the sympatho-adrenal system in equine grass sickness. Statistical evaluation determined differences of hormone levels between seven horses with grass sickness (one acute, five subacute and one chronic), six horses with colic (one with laminitis) and 16 control horses before and after mild stress. Plasma levels of the hormones were higher in horses with acute and subacute grass sickness than in the other groups. No differences were detected between horses with colic and stressed contr...
O'Callaghan MW.This study was initiated to determine the accuracy of M-mode echocardiography in measuring left ventricular dimensions and estimating heart weights in horses. Left ventricular free wall and interventricular septal thickness and left ventricular external and internal diameters were measured and heart weights estimated from the echocardiograms of 47 horses. Autopsy measurements of the same parameters were then recorded. Statistical comparison of the data demonstrated: (1) Systolic measurements of wall thickness more closely resembled the heart in death than the diastolic measurements; (2) good c...
Goulden BE, Anderson LJ, Cahill JI.An endoscopic survey was performed to assess arytenoid cartilage movement during quiet respiration in 48 Clydesdale horses. Physical characteristics which could influence the length of the recurrent laryngeal nerves were also recorded from these horses and the relationship of these characteristics to the presence of abnormal left arytenoid cartilage movements was assessed statistically. Some degree of abnormal arytenoid movement was observed in 50% of the animals over one year of age. No significant correlation between sex, age, estimated weight, height, or neck length could be found although ...
Júnior AMCA, da Silva AH, Buroxid RP, Padovan JR, Nunes AT, Poleti MD, Fukumasu H, Gobesso AAO.Intense training in athletic foals may alter fecal microbiota, highlighting the need for nutritional strategies such as hydrolyzed collagen supplementation. Objective: This study aimed to evaluate the effects of dietary hydrolyzed collagen on the fecal microbiome of weanlings in training. Methods: Twenty Mangalarga Marchador foals (206 ± 18 kg; 7 ± 1 mo age) were assigned to two groups: a supplemented group (50 g/day of hydrolyzed collagen for 180 days) and a control group. A completely randomized design with repeated measures over time was used. Foals were exercised five consecutive days pe...
Boubakeur E, Belmdjahed M.Gestation length is a key parameter in equine reproductive management, yet its variability remains poorly documented in Barb and Arabian mares under Algerian conditions. Objective: This study aims to determine gestation length in mares and to assess the influence of various factors, including breed, year of mating, mating month, mare age, parity, reproductive status, stallion and the foal's sex on gestation duration. Methods: A total of 133 mares from the National Stud Farm of Tiaret (Algeria) were monitored over the period 2021-2024. Results: The mean gestation length was 332.5 days (range: 3...
Almutairi S.Research directly examining the cognitive and academic correlates of horseback-riding in childhood remains limited. This study examined the relationships among monthly horseback-riding hours, executive function (EF), and mathematics achievement in children aged 7–9 years. A sample of 262 participants from Saudi Arabia was assessed using parent interviews and official educational records, with data collected from sports clubs and horse stables. EF was modeled as a latent construct—including organization and planning, working memory, emotion regulation, self-control, and motivation—`using ...
Laseca N, Molina A, Marshall T, González I, Poyato-Bonilla J, Valera M.Accurate parentage assignment is essential for managing livestock breeding and genetic improvement. This study evaluated a breed-specific SNP panel (375 SNPs) for the Pura Raza Española (PRE) horse, comparing its performance against the traditional STR reference panel (18 microsatellite) and the international ISAG SNP core panel (378 SNPs) across population scenarios differing in levels of inbreeding and kinship. The PRE-specific SNPs were selected from the Axiom EQUIGENE array based on high genotyping reliability (call-rate > 99%), Mendelian error minimization, Hardy-Weinberg equilibr...
Sun W, Shen Z, Cairen D, Luo P, Yao X, Meng J, Zeng Y.Body measurement traits are a direct production indicator reflecting growth status and guiding genetic selection. Identifying molecular markers associated with body measurement traits could accelerate animal breeding programs. The Yanqi horse, an important indigenous breed in Xinjiang, is primarily distributed in the Bayingolin Mongol Autonomous Prefecture. However, molecular markers linked to body measurement traits in Yanqi horses remain uncharacterized. In the present study, whole-genome resequencing was performed on 183 Yanqi horses, yielding 13,366,672 single-nucleotide polymorphisms (SNP...
de Siqueira RF, Brito LA, de Figueiredo IM, Dos Santos ACR, Dos Anjos LS.Lineage-based selection is central to the Quarter Horse industry and is often justified by the assumption that morphology determines locomotor function. However, objective evidence linking static conformation to discipline-specific locomotor behaviour under standardised conditions remains limited. Objective: To investigate whether morphological differences among Quarter Horse disciplines are associated with distinct locomotor patterns or whether locomotor function converges across disciplines despite morphological variation. Methods: Cross-sectional. Methods: Barrel racing, reining, and ranch ...
Irons A, Culwell J, Nicodemus MC, Vandiver M, North E, Cavinder C, Rios de Alvarez L, Williams T.Phenotypic characterization of traits like gait and coat color is useful for minor breed identification and conservation. The Mountain Pleasure Horse (MPH) is a minor American breed as it is listed as threatened by the Livestock Conservancy. Objective: The study objective was to utilize phenotypic characterization for identifying gait and coat color phenotype of the MPH. Methods: Gait was characterized utilizing frame-by-frame analysis to identify spatiotemporal variables of purebred horses (n = 6) performing the flat walk and saddle rack. Coat color was characterized using coat color assi...
Markowitz JS.Steeplechase jockeys compete in high-risk races requiring horses and riders to clear fixed obstacles at speed. Although rider dislodgement events are recognized hazards, their incidence and participation consequences are not well characterized. Methods: This retrospective observational study used publicly available race charts from United States National Steeplechase Association races (2023-2025). Dislodgement events were defined as falls or lost rider events. Incidence rates were calculated per 1,000 starts, and timber and hurdle races were compared using Poisson regression. Rider interruptio...
Arı HH, Duro S, Alpak H, Tulobaev A, Ceylan N, Ashyk A, Salykov R, Djordjevic M, Gündemir O.This study aimed to evaluate sexual dimorphism in Kyrgyz horse skulls by separating size and shape components using Mosimann log-shape ratios, based on 18 linear cranial measurements recorded from 39 specimens. Raw linear data were analyzed alongside size-corrected Mosimann log-shape ratios to distinguish overall size from size-independent shape. Males showed larger raw means than females for all 18 variables, and 14 measurements remained significant after false-discovery-rate correction. The strongest raw differences involved skull length to nasale, total skull length, nasal length, breadth b...
Janura M, Å igutová A, Lantelme-Faisan V, HonzÃková L, Bizovská L.Equine Assisted Physiotherapy (EAPT; formerly known as hippotherapy) is known to improve functional mobility, gross motor skills, and postural stability in individuals with Down syndrome (DS). However, it may be challenging to implement as a long-term intervention. The aim of the current study was to assess whether even a single session of EAPT can have effect on postural stability in children with DS. Methods: Nine children with DS underwent a single session of EAPT. Postural stability before and immediately after the EAPT session was assessed with the bipedal stance (variability of lower tru...
Witt J, Ashenefe Wassie B, Tadesse TA, Wakane WZ, Adane AT, Deressa SG, Mor SM.Ethiopia has not only one of the largest livestock populations in Africa, but also a substantial growing human population, increasing the risk of zoonotic disease transmission. Anthrax is a priority zoonosis in Ethiopia due to its risks to both human and animal health. Utilising 13 years of retrospective data (2008-2020) from 92 zones, this study investigated the spatio-temporal distribution of livestock anthrax cases in Ethiopia. High variability in annual incidence was observed, with the lowest number of cases (n=2357, 3.73 %) in 2018 followed by the highest number of cases (n=8210, 12.98 %)...
Próchniak T.The aim of this study was to pilot the assessment of sport predispositions in warmblood horse breeds, both domestic and foreign, and to evaluate factors influencing their performance. Data from 293 horses (725 starts) competing in national Grand Prix events with obstacle heights of 140-145 cm were analysed using general mixed models. The origins of Polish Halfbred Horses were examined, and correlations between results in the Young Horse Championships and later Grand Prix performance were assessed. Results showed that performance is significantly influenced by genetic factors, such as breed and...
Marlowe JL, Hughes L, Barrey E, Leeb T, Bellone R, McCue ME, Durward-Akhurst S. Advances in whole-genome sequencing (WGS) technology have led to the widespread adoption of WGS for investigating genetic diseases and traits in domestic animals. This has created a need for improved methods for prioritizing candidate causal variants. One way variants are prioritized is using variant annotators that predict variant effects based on their proximity to genomic features and effect on amino acid sequence. However, validation of variant annotators for domestic animal genomes is lacking. In this study, we calculated the agreement of three popular variant annotators, Ensembl Varian...
Bou T, Ding W, Gong W, Li Z, Shi X, Dugarjaviin M, Bai D, Yang L.The Grassland Xichun horse is an emerging crossbred population developed from Xilingol mares and Thoroughbred stallions in Inner Mongolia, China, yet its blood physiological profile has not been systematically characterized. In this study, we compared 32 hematological and serum biochemical parameters between 177 Grassland Xichun horses and 35 Xilingol horses maintained under the same extensive grazing conditions. Following Benjamini-Hochberg FDR correction, 17 of 32 parameters differed significantly between breeds. Grassland Xichun horses showed markedly higher RBC count (9.145 vs 7.905 × 10Â...
Shojaei B, Mousanejad E, Afshar FK, Pourjafari F.Morphological variation in equine limb dimensions provides valuable insight into breed-specific characteristics, with biometric parameters serving as reliable tools for such evaluations. Unassigned: This study aimed to provide a quantitative characterization of the external morphology of the limbs in Iranian Arab horses. Unassigned: Morphometric data were collected from 30 adult specimens of this breed, encompassing key anatomical measurements: scapula length, arm length, forearm length, metacarpus length, forepastern length, metacarpus circumference, femur length, gaskin length, metatarsus le...
Cullen E, Carslake HB, Henderson I, Stoneham S, Pinchbeck GL, Archer DC.Broodmares are at increased risk of gastrointestinal colic. However, colic risk factors specific to this population have not been investigated. Objective: To investigate horse- and management-level risk factors for post-partum colic in a cohort of Thoroughbred broodmares in the United Kingdom and Ireland. Methods: Prospective, nested case-control study. Methods: Twenty-nine Thoroughbred stud farms in the United Kingdom and Ireland were recruited, and 1044 mares were followed over the 2021 and/or 2022 foaling seasons. Data were collected on signalment, medical and management history for post-pa...
Delecave Dias T, Hauser RG, Cleary KB, Durward-Akhurst S.Arrhythmias can cause poor performance and sudden death in horses. Long-term (>24 h) electrocardiogram (ECG) monitoring has been used to identify arrhythmias in humans and is superior to short-term monitoring for transient arrhythmia detection. Televet is the current equine gold-standard ECG device. The Cardea SOLO™ (CS) is a single-use monitor with automated ECG analysis software allowing ECG monitoring for 7 days. Objective: Our objective was to validate the performance of the CS compared to the Televet. Methods: Method validation. Methods: ECGs were performed on 12 healthy horses s...
Cranston N, Buckley P, Rose L, Loy J, Randle H.Weaning is a stressful time in a foal's (Equus caballus) life. As humans artificially manage weaning in domestic horses, it provides an opportunity to safeguard horse welfare early in life, with potential long-term benefits. While numerous studies have examined the effects of different weaning and management interventions on foal stress, optimal weaning practices have yet to be identified. Overall purpose of the study: To identify which weaning interventions and management practices have the greatest potential to improve foal welfare based on physiological and behavioural outcomes. Research qu...
Takahashi K, Mukai K, Shirai T, Ebisuda Y, Sugiyama F, Yoshida T, Hatta H, Kitaoka Y.This study investigated whether different pacing patterns during high-intensity exercise elicit distinct transcriptional responses in equine skeletal muscle. Eight Thoroughbred horses completed two treadmill exercise sessions in a randomized crossover design. In the positive-pacing condition, horses exercised at 110% maximal O₂ uptake (V˙O₂max) for 1 min followed by 90% V˙O₂max for 1 min, whereas in the negative-pacing condition, the order was reversed. At 4 h after exercise, the positive-pacing protocol resulted in upregulation of 1,989 genes and downregulation of 840 genes, whereas t...
Bordignon V, Buratini J, Cue RI, Barrilari V, Gonçalves MA, Merlini G, Fernandes CB, Squires E, Pontes JHF, Fleury PDC.Equine OPU‑ICSI supports commercial IVEP, yet substantial variability persists. We retrospectively analyzed a large dataset generated in Brazil spanning Quarter Horses, Warmbloods, and Mangalarga to evaluate whether predictors previously identified in the literature show comparable patterns under distinct ecological and breeding conditions. Overall oocyte and embryo outcomes were aligned with broadly reported trends from previous studies. Oocytes retrieved from estrous mares bearing a dominant follicle exhibited higher maturation and blastocyst rates. Stallion effects segregated into distinc...
Santana ML, Bignardi AB.Resilience, defined as the capacity to maintain consistent performance under variable conditions, has emerged as a relevant breeding objective in livestock systems, yet remains largely unexplored in equine populations. The objectives of this study were to (1) derive indicators of resilience from longitudinal barrel racing time (BRT) records in Brazilian Quarter Horses, (2) estimate genetic parameters for these indicators, and (3) quantify their genetic relationships with BRT and accumulated career earnings (ACE). The dataset comprised BRT records from barrel racing events held between 2010 and...
Gao Y, Luo Z, Dong Z, Li S.Equine colic remains one of the leading causes of mortality in horses, with timely diagnosis and accurate prognostic assessment being critical for clinical decision-making. In recent years, artificial intelligence (AI) has been increasingly applied to support diagnostic and prognostic evaluation in veterinary medicine. However, the scope, methodological characteristics, and performance of AI models in equine colic have not been systematically mapped. Therefore, this scoping review was conducted to summarize current AI applications in equine colic, identify commonly used algorithms, describe re...
Khanahmadi A, Rahimi Mianji G, Moradi Shahrebabak H, Hafezian SH, Zandi MB.Breakthroughs in genomic technologies have enabled the formulation of methods to identify genomic variation in domestic animal species. Detection of the variation is necessary because it is associated with breed characteristics and economic importance in domestic animal genetics. Unassigned: This study aimed to identify the genomic regions in Turkmen and Kurdish horse breeds that have been the target of different selections over many years. It also sought to locate the genes and Quantitative trait loci (QTL) in these regions that contributed to the differentiation of these two breeds or the di...
Demeyere M, Dufourni A, Verhaeghe LM, Vernemmen I, De Backer T, van Loon G, Decloedt A.Mitral valve regurgitation (MR) is frequently detected in horses, but its classification and prognostication remain challenging. This study investigated whether auscultatory findings and left atrial function are associated with MR severity. Methods: Fifty controls (no/trivial MR) and 101 MR horses (58 mild, 36 moderate, seven severe) were retrospectively evaluated. All were in sinus rhythm and underwent auscultation and echocardiography. Mitral regurgitation severity was graded using a scoring system. Systolic murmur characteristics (duration, type and grade) were recorded. Left atrial functio...
Asadollahpour Nanaei H, Seguin-Orlando A, Negara K, MacLeod JN, Kalbfleish T, Orlando L.The Thoroughbred horse is a legacy of centuries of selective breeding for speed, emerging from the admixture of British mares and imported Oriental stallions. While previous work explored its genetic diversity, inbreeding, and selection signatures, the breed demographic and selection dynamics during the 20-century remain poorly understood. Here, we sequenced the genome of Phar Lap, a late-1920s/early-1930s racing champion, and analyzed the largest time-series of Thoroughbred whole-genome sequences, within a global panel of 850 horse genomes. Demographic modeling reveals a marked decline in gen...
Allen SE, Taylor S, Given J, Verheyen KLP.Horse falls are an important safety and welfare concern in jump racing, as they are associated with an increased risk of equine fatality and injury, as well as jockey injury. Objective: To identify risk factors for horse falls in British jump racing. Methods: Retrospective cohort. Methods: All jump race starts made on British racecourses between January 2010 and April 2023 were considered. Available horse, race, racecourse, trainer and jockey data were collated and combined with faller data recorded in official databases. Horses that were 'brought down' by another horse were not considered a f...
Gong Y, Liu X, Zheng Z, Zeng S, Zhang Y, Pu Y, Pan J, Ma Y, Jiang L.The selection of horses has been instrumental in shaping long-range mobility, advancing warfare strategies, and diversifying equine phenotypes. However, the structural variants (SVs) favored by this process remain largely unexplored. Utilizing high-fidelity Pacific Biosciences sequencing, we assembled three high-quality horse genomes, incorporating 237 Mb (9.48%) of novel sequences relative to the existing reference genome. These assemblies achieved an average Benchmarking Universal Single-Copy Orthologs completeness of 95.1%. By employing a graph-based approach, we genotyped 23,163 high-con...
Young LM, Courtney ER, Freeland RB.The racing outcome of horses that have undergone surgical repair of neonatal rib fractures is not well documented. Objective: To evaluate the impact of surgical repair of neonatal rib fractures on subsequent sales and racing performance in Thoroughbreds. Methods: Retrospective cohort study. Methods: Medical records of neonatal Thoroughbreds that underwent surgical repair of rib fractures at a referral hospital between 2014 and 2025 were reviewed. Sales and racing data were obtained from publicly available databases. Outcomes assessed included sale price at weanling and yearling sales, total ca...
Puentes MMM, Guzman YL, Torreglosa JCT, Isaza PAL, Guzman-Barragán BL.Equine infectious anemia (EIA) is a persistent lentiviral disease with important sanitary and economic implications in tropical regions; however, epidemiological information in Colombia remains limited. Objective: To estimate seroprevalence, identify risk factors, and evaluate hematological alterations associated with EIA in horses from Casanare, Colombia. Methods: A cross-sectional study including 1,228 horses from 204 production units across 121 rural districts. Serological diagnosis was performed using agar gel immunodiffusion. Demographic and management data were obtained through an epidem...