Equids are members of the family Equidae, which includes modern horses, donkeys, and zebras, as well as extinct species. Equids are characterized by their long limbs, single-toed hooves, and herbivorous diet, which is primarily composed of grasses. Horses, specifically, have been domesticated for thousands of years and have played significant roles in agriculture, transportation, and sport. This page compiles peer-reviewed research studies and scholarly articles that explore various aspects of equids and horses, including their evolution, physiology, behavior, and interactions with humans. The collected works provide insights into the genetic diversity, adaptive traits, and conservation efforts related to equid species.
is one of the most pathogenic nematodes affecting equids. Larval migration through the cranial mesenteric artery (CMA) with attendant arteritis and thromboembolism can result in fatal non-strangulating intestinal infarction. Once considered a historical disease, recent studies have described the reemergence of this pathogen in several European countries; however, little is known of the current prevalence of in the Canadian horse population. Unassigned: To determine the prevalence of active cranial mesenteric arteritis in horses submitted for postmortem examination to the Diagnostic Services...
Taylor DEF, Lancaster BE, Ellis AD.Visual observation to record grass intake is time-consuming and labour-intensive. Technological methods, such as activity monitors, have been used but only record head position. This study aimed to evaluate sound recorders attached to headcollars to acoustically measure grass intake behaviour in horses as a low-cost alternative method. Pilot Study 1 assessed 6 × 11 min periods comparing bites/min and chews/min between video footage (VD) and sound recorders (SR). Grazing was identified audibly (SR) and visually through soundwave pattern software (SR). Chew rates (SR: 47 ± 5 chews/min, VD: 43 ...
Shaffer SK, Medjaouri O, Swenson B, Eliason T, Nicolella DP.The ability to quantify equine kinematics is essential for clinical evaluation, research, and performance feedback. However, current methods are challenging to implement. This study presents a motion capture methodology for horses, where three-dimensional, full-body kinematics are calculated without instrumentation on the animal, offering a more scalable and labor-efficient approach when compared with traditional techniques. Kinematic trajectories are calculated from multi-camera video data. First, a neural network identifies skeletal landmarks (markers) in each camera view and the 3D location...
Staiger EA, Pereira de Toledo A, Rizzato Paschoal V, Patterson Rosa L.Horse gaits are a trait highly selected and prized in diverse breeds. Meanwhile, gait classification relies mostly on subjective visual observations by evaluators. Noninvasive equipment able to track locomotion in horses and output quantitative gait parameters is not only helpful in evaluating locomotion but also in designating gait types and its variations. Equine locomotion pattern designation based solely on observer evaluation can be subjective; therefore, utilizing tools that provide quantitative results and track individual limb movements, especially during intermediate-speed gaits, can ...
Ferreira I, Pinto JG, Oliveira EGL, Azevedo MCBS, Marcolino LMC, Ferreira-Strixino J.Habronema muscae is a parasitic nematode that causes habronemiasis in horses, leading to chronic skin lesions. The parasite is transmitted via flies, and larvae deposited in wounds result in difficult-to-heal "summer sores". This case study involved treating a 9-year-old gelding male horse with recurrent habronemiasis using photodynamic therapy (PDT) concurrent with conventional treatments. The horse presented with ulcerated, exudative wounds on its limbs and face, unresponsive to traditional treatments. PDT was applied over six months, using methylene blue (MB) as a photosensitizer, combined ...
Choi Y, Jung Y, Wickens CL, Yoon M.Horses are social animals, with early life experiences playing a crucial role in their physiological and behavioral development. This study explored the influence of herd dynamics and foundational training on behavioral and hormonal changes in weaned foals. We examined 13 six-month-old Quarter Horse foals over a three-month training period, performing behavioral observations, temperament assessments, and hormone analyses at the start, midpoint, and end of the training. The results indicated that affiliative behaviors decreased significantly, while agonistic behaviors first increased and then d...
Vallejo-Soto P, Dorado J, Herrera-García R, Álvarez-Delgado C, Gómez-Laguna J, Santiago Á, Manrique M, González Ariza A, León Jurado JM....Assisted reproductive techniques are often extrapolated from horses to donkeys, despite poorer fertility outcomes in jennies. This issue has been attributed to unknown uterine species-specific differences. This study compared, through histomorphometry, the endometrium of jennies and mares. Endometrial biopsies (N = 12) were taken from reproductively sound jennies (n = 6) and mares (n = 6) in estrus. Histomorphometric analysis evaluated luminal (LE, µm) and glandular epithelium height (GE, µm), glandular lumen diameter (LD, µm), glandular area (GA, µm), the number of glands (#G), and glandu...
Liu J, Yang Y, Wen L, Wen M, Zeng Y, Ren W, Yao X.The Kazakh horse is an outstanding dual-purpose dairy and meat breed in China, characterized by early maturity, tolerance to coarse feed, and strong stress resistance. Previous studies have examined gene expression patterns in the testicular tissues of Kazakh horses at different age stages, but the molecular mechanisms regulating testicular sexual maturation remain unclear. To address this gap, this study conducted HE staining and in-depth transcriptome sequencing analysis of Kazakh horse testicular tissue before and after sexual maturity. HE staining showed that the G3 group had well-formed s...
Alves NC, Freitas MM, Faria JRD, Horta CL, Martins-Filho OA, Araújo MSS, Costa GMJ, Costa EA, de Almeida FRL, Amaral PHR, Pérez JCG, Lana ÂQ....Niacin acts as an antioxidant that protects cells from oxidative damage. This study evaluated the effects of adding niacin to the equine semen freezing extender on sperm quality and gene expression after cryopreservation. Ejaculates from ten stallions were frozen using the INRA 96 extender (control) or extenders supplemented with 10- and 20-mM niacin. After thawing, sperm were analysed for motility, kinematics, viability, membrane integrity, mitochondrial potential, lipid peroxidation, nitrite, hydrogen peroxide, malondialdehyde and reactive oxygen species (ROS) concentrations, DNA integrity, ...
Mendoza Flores JE, Terrazas A, Lara Sagahon AV, Aleman M.Parasympathetic tone activity (PTA) and its association with behavior in conscious versus anesthesia in horses are unknown. Objective: To study PTA, heart rate (HR), minimum alveolar concentration (MAC), and mean arterial pressure (MAP) during castration under anesthesia. To study PTA, HR, Horse Grimace Scale (HGS), locomotor activity (LA), and behavior in conscious horses before and after castration. Methods: Pilot study including seven healthy adult horses. After habituation (days 1, 2, and 3), PTAm, HR, HGS, LA, and behavior were investigated during pre-surgery (days 4-, 5-, and one-hour pr...
Jafari H, Abebe BK, Cong L, Ahmed Z, Zhaofei W, Sun M, Muhatai G, Chuzhao L, Dang R.The domestication and selective breeding of horses have profoundly influenced the emergence of adaptive traits and stress resistance mechanisms, shaping modern equine populations. This comprehensive review examines the genomic foundations of these traits, emphasizing recent advancements in high-throughput sequencing technologies and bioinformatics. These tools have elucidated the genetic underpinnings of key characteristics such as endurance, speed, metabolic efficiency, and disease resistance. Importantly, the review identifies and connects gene variants associated with thermoregulation, immu...
Valenchon M, Reigner F, Lefort G, Adriaensen H, Gesbert A, Barrière P, Gaude Y, Elleboudt F, Lévy I, Ducluzeau C, Dupont J, Lainé AL, Uszynski I....Social interactions shape both the physiological and behavioural development of offspring, and poor care/early caregiver loss is known to promote adverse outcomes during infancy in both animals and humans. How affiliative behaviours impact the future development of offspring remains an open question. Here, we used Equus caballus (domestic horse) as a model to investigate this question. By coupling magnetic resonance imaging, longitudinal biobehavioural assessments and advanced multivariate statistical modelling, we found that prolonged maternal presence during infancy promotes the maturation o...
Key K, Kirkegaard J, Berg K, Andresen KR, Skov Hansen S.A handheld smartphone-based computer vision algorithm (RealHorse® [RH]) offers accessible alternatives for equine gait analysis but requires validation against a gold-standard three-dimensional multicamera optical motion capture system (Qualisys® [QS]). Objective: To evaluate the accuracy and precision of RH in measuring vertical displacement signals (VDS) at the eye, withers, back and croup in horses trotting on a straight line and on a circle. Methods: Cross-sectional comparative validation study of a markerless computer vision algorithm. Methods: Fifty-nine horses were recorded while trot...
Friend MM, McGaffigan EM, Hall SM, Staniar WB, Smarsh DN.Equine blood samples are often collected in uncontrolled, distant environments and stored for later analysis. Objective: This study aimed to determine how sample storage methods influence complete blood count (CBC) parameters, hypothesizing that temperature and time elapsed from collection to analysis would affect CBC parameters. Methods: Blood samples were collected from 10 healthy Quarter Horse mares (age: 13 ± 4.5 years old) and stored in EDTA tubes at room temperature (22°C), above ice (8°C), refrigerated (4°C), or in contact with ice (2°C). The IDEXX ProcyteDx was used to obtain CBCs...
Cortes D, Mendoza M, Raudsepp T, Ferrer M.Cervical duplication is a disorder of sexual development (DSD) that may be present in the absence of chromosomal aberrations. It is a rare cause of infertility in mares and is attributed to the failure of the Müllerian ducts to fuse properly, leading to the persistence of the median walls along the whole length of the cervix. This case report involves a 13-year-old American Quarter Horse mare with cervical duplication. Prior to this diagnostic, the mare was bred multiple times, but pregnancy was not achieved. The mare presented for a breeding soundness evaluation. During the examination an ab...
Amaral TM, Ramos PDCA, Silva RA, Ferreira MM, Filho EDS.In the context of Brazilian equestrian sports, the Quarter Horse (QH) breed has the third largest population of registered horses and stands out for its numerous abilities in various disciplines. Studies on equine health and athletic performance parameters are scarce, especially involving molecular markers. Objective: This study aimed to investigate the differential expression of microRNAs and target genes involved in metabolic pathways of exercise and to assess hematological and clinical changes in 10 horses (Equus caballus Linnaeus) of the QH breed under different physiological conditions. H...
Bachmann M, Bochnia M, Wensch-Dorendorf M, Glatter M, Schäfer S, Simroth K, Greef JM, Zeyner A.Feed intake and digestibility are important indicators for sufficient nutrient supply, but they can be assessed only to a limited extent in horses on pasture. In horses, feed intake is embedded in a complex behavioural pattern of searching, selecting, chewing and almost constant movement called foraging. The objectives of this study were to estimate organic matter intake (OMI) and organic matter digestibility (OMD) in six horses, 24 h/day on pasture, based on plant alkanes and synthetic n-hexatriacontane (C) excretion. A multi-compartmental model was fitted to the marker excretion and the C m...
Johnson A, Karam B, Schroeder O, McKaig L, Loesch K.A 12-month-old miniature horse filly was presented because of laminitis, suspected lymphangitis, and pyrexia. Although the filly's initial physical examination and diagnostic tests suggested an infectious etiology, ultrasonographic findings were suspicious for generalized steatitis. This was confirmed histopathology. The filly experienced full recovery with continued resolution of clinical signs at 18 mo after presentation. This case included aspects similar to those of previously reported clinical presentations, as well as long-term follow-up in a breed that is not overrepresented, providing...
