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.
Science (New York, N.Y.)January 19, 1973
Volume 179, Issue 4070 235-239 doi: 10.1126/science.179.4070.235
Protsch R, Berger R.Our dates show that cattle and pigs were first domesticated in Europe. Sheep, which were thought to have become extinct in Europe during the terminal Pleistocene, also appear first in Europe. However, there remains little doubt that sheep were first domesticated in the Near East or Turkey, since no wild sheep appear to have existed in Europe at the beginning of the Holocene. Dogs were domesticated in both the Near East and Europe at virtually the same time. In the Near East, Asiab, at around 8000 B.C., qualifies as the first center of goat domestication. It is also the earliest center of domes...
Vetterling JM, Thompson DE.Kidneys from 5 of 40 ponies (Equus caballus) and from 3 of 14 burrows (Equus asinus) were found infected with Klossiella equi. In addition to previously reported sporogonous stages in epithelial cells of Henle's loop, schizogonic stages in endothelial cells of Bowman's capsule and epithelial cells of the proximal convoluted tubules are described. The association of macro- and micro-gametocytes in syzygy is discounted, and a microgametocyte with 8 to 10 microgametes is characterized. Microgametes in the process of migrating to macro gametes are reported. A life cycle for this parasite is propos...
Nunes MM, Gurgel JRC, Munhoz ML, de Giuli V, Carneiro GF, Miragaya MH, Gallelli MF, Guimaraes JD.The aim of this study was to assess the effect of lyophilized freezing extenders, which can be stored at room temperature, on stallion post-thaw sperm total motility (TM). Ejaculates of 28 stallions were frozen with four different extenders: two commercial freezing extenders offered worldwide and two novel lyophilized extenders (STAR and MX3), and two different cryopreservation protocols (CP1 with an equilibration period of 20 min. and CP2 with an equilibration period of 60 min.). The TM was assessed after thaw. Mean TM did not show significant differences between cryopreservation protocols wi...
Ramírez-Agámez L, Castaneda C, Hernández-Avilés C, Grahn RA, Raudsepp T, Love CC.Two methods for preimplantation genetic testing (PGT) have been described for equine embryos: trophoblast cell biopsy (TCB) or blastocoele fluid aspiration (BFA). While TCB is widely applied for both in vivo- and in vitro-produced embryos, BFA has been mostly utilized for in vivo-produced embryos. Alternative methods for PGT, including analysis of cell-free DNA (CFD) in the medium where in vitro-produced embryos are cultured, have been reported in humans but not for equine embryos. In Experiment 1, in vivo- (n = 10) and in vitro-produced (n = 13) equine embryos were subjected to BFA, cultu...
Gallacher K, Woolford L, Santos LC, Serpa PBS, Len J, Gilbert RO, Kind KL.Endometrial health is vital for the reproductive efficiency of broodmares and accurate diagnostic testing is crucial for directing the best treatment options and outcomes. Confocal laser endomicroscopy (CLE) is an endoscopic technique for obtaining in-vivo, real-time microscopic imaging of tissues using a fiber optic probe. CLE relies on induced tissue fluorescence and fluorescein sodium, given intravenously, is the contrast agent most used in human medicine. This study aimed to determine the feasibility of CLE for imaging equine endometrium and determine a standard dose of fluorescein sodium ...
Caldevilla M, Ferrante A, Neild DM.The addition of antioxidants to cryopreservation media reportedly improves sperm post-thaw quality and reproductive performance after artificial insemination. Therefore, the objectives of this study were to evaluate if the addition of L-carnitine and pyruvate to freezing media, or their addition to samples after thawing, improves the post-thaw quality of equine spermatozoa. Thus, in Experiment 1, stallion semen samples were cryopreserved in: (1) EDTA-glucose-based extender with 20% egg yolk and 5% dimethylformamide (EDTA control); (2) skim milk-based extender with 20% egg yolk and 5% dimethylf...
Blanco-Doval A, Barron LJR, Bustamante MÁ, Aldai N.Mare milk has often been considered a food product with potential functional properties. However, the bioactive compound composition of mare milk, including vitamins and other minor bioactive compounds, as well as factors affecting this composition have scarcely been studied. Therefore, the present study aimed to characterize the changes during lactation in the content of water- and fat-soluble vitamins and total polyphenols, and the total antioxidant capacity of mare milk from semi-extensive farms. A total of 310 individual milk samples from 18 mares belonging to three commercial farms and 12...
Hernández-Avilés C, Ramírez-Agámez L, Varner DD, Raudsepp T, Love CC.Cases of stallion subfertility due to acrosome dysfunction have been recognized since the 1990s. While some of these were observed in stallions with reduced sperm motility and morphology, a more severe form has been reported in stallions with normal-to-excellent sperm quality parameters, which is also uniquely observed in individuals of the Thoroughbred registry. These stallions carry a susceptibility genotype (A/A-A A in the gene FKBP6, exon 5) for Impaired Acrosomal Exocytosis (IAE). Current clinical observations from our group have identified a few highly subfertile stallions from other bre...
Devine E, McCracken M, Miller L, Miller D, Anderson SL, Hunt JA.Castration is one of the most common surgeries performed in equine practice. Veterinary students require deliberate practice to reach competence in surgical procedures including equine castration, but availability of patients limits students' practice opportunities. A recumbent equine castration model was created and evaluated using a validation framework consisting of content evidence (expert opinion), internal structure evidence (reliability of scores produced by the accompanying rubric), and evidence of relationship with other variables, specifically the difference in scores between experts...
Watson WL, MacKay JRD, Dwyer CM.This study focuses on recreational horse owners in the UK and Ireland to explore the relationship between horse characteristics and welfare issues. An online questionnaire was distributed to 1501 horse owners to collect data on the owners, horses, and health/behavioural issues. Most respondents were female (98%), lived in England (56%), and did not insure their horses for veterinary costs (51%). Horses were typically over 5 years of age (96%), taller than 154 cm (55%), and mostly geldings (65%). Common welfare issues reported included lameness (26%), handling problems (11%), antisocial behavio...
Pezzanite LM, Nelson BB, Downey AC, Gadomski B, McGilvray K, Baer K, Kappel SM, Nout-Lomas Y, Seim HB, Easley JT.To determine the biomechanical properties of pedicle screw and rod (PSR) constructs alone and with an interbody fusion device (PSRIFD) for equine ventral cervical vertebral stabilization. Methods: Cadaveric ex vivo biomechanical analysis. Methods: A total of 14 (n = 14) adult equine cervical vertebral columns. Methods: Cervical vertebral columns were stabilized by PSR alone (n = 6) or PSRIFD (n = 5). Three columns were left unaltered as controls. Non-destructive biomechanical testing showed the kinematic range of motion (ROM), compliance, and neutral zone of each spinal unit in the...
Dubeibe-Marin DF, Borraez DF, Gomez-López DL, Velasco-Acosta DA.This study evaluated the effect of the presence and location of the corpus luteum (CL) on quantity and competence of equine cumulus-oocyte complexes (COCs). Pairs of ovaries were collected at the slaughterhouse and classified into three groups: ovaries with CL (CL+); ovaries with CL in the contralateral ovary (CL-) and ovaries without a CL (NCL). Were evaluated COC quantity, morphology, nuclear maturation rate, and intrafollicular progesterone concentration and gene expression (BAX, BMP-15, ODC1, GDF9, AURKA) in both cumulus cells and oocytes after in vitro maturation. Results showed a lower r...
Vieira GS, Peneiras ABV, Soares TSC, Alonso MA, Curcio BR, Fernandes CB, Oliveira RA.Advancements in equine neonatology enable continuous monitoring of mares throughout pregnancy. However, reference values for oxygenation and biochemical parameters in newborn foals remain limited. Objective: This study aimed to assess the oxygenation status of healthy Mangalarga Marchador foals from birth to 24 h postpartum by evaluating blood gas analysis, Apgar scores, and biochemical and hematological parameters. Methods: Thirty healthy Mangalarga Marchador foals were evaluated. Blood samples were collected from the umbilical artery at birth (T0) and from the dorsal metatarsal artery at 15 ...
Carvalho KS, de Barros CSL, Mendonça FS, Machado M, Riet-Correa F.In Brazil, CNS diseases in equids were little known until the 1980s. Since then, several diagnostic laboratories have been operating in different universities, initially in the South and Southeast regions and, later, in the Central-West, Northeast and North regions. However, the knowledge accumulated from the diagnoses of nervous system diseases of equids made at these institutions over the years has not been reviewed comprehensively, and many papers are published in Portuguese. Here, we review 18 diseases that occur in the nervous system of equids in Brazil, including some critical infectious...
Urion R, Lustgarten M, Hostnik ET.Technological developments in imaging modalities have advanced the diagnostic capabilities for equine tendon and ligament injuries beyond the traditional methods. This review examines elastography techniques in ultrasonography that assess tissue stiffness and strain properties, computed tomography (CT) innovations including PET/CT fusion and dual-energy CT, and emerging applications of diffusion-weighted MRI for evaluating fiber microstructure and functionality. These complementary approaches offer veterinarians improved means to detect early injuries, assess structural integrity, monitor heal...
Martano M, Montagnaro S, Power K, Cuccaro B, Cutarelli A, Maiolino P, Restucci B.This study investigated the presence of δ bovine papillomaviruses (BPV-1, BPV-2, BPV-13, BPV-14) in equine skin lesions from Southern Italy, focusing on equine sarcoids and their histopathological correlations. 63 equine skin samples were analysed using PCR and sequencing for BPV detection, and their histopathological features were assessed. BPV DNA was detected in 69.84% of the samples, with BPV-1 and BPV-2 being the most prevalent genotype, followed by BPV-13, while BPV-14 was not detected. BPV DNA was also found in non-sarcoid tumours and non-neoplastic conditions. Histopathological analys...
Durham AE.This study aimed to further define and quantify possible cross-reactive peptides when measuring plasma adrenocorticotropic hormone (ACTH) concentration in equids. Equine plasma samples were spiked with known concentrations of exogenous manufactured peptides comprising human ACTH, ACTH (corticotropin-like intermediate lobe peptide, CLIP) and ACTH (corticotropin inhibiting peptide, CIP). All samples were assayed in duplicate using Siemens Immulite 2000xpi chemiluminescent assay (CLA) and Tosoh AIA-900 immunoflurorescent assay (IFA). As expected, ACTH was measured by both assays although higher v...
Martins ALM, Estevam LGTM, Freire MA, Lima ACVMDR, de Oliveira FCB, Dutra-Rêgo F, Carvalho GML, Ribeiro VM, Paz GF.Equine leishmaniasis is a widespread disease in Brazil, mainly caused by Leishmania (Viannia) braziliensis, with occasional cases involving Leishmania (Leishmania) infantum. This study reports a mixed infection in a 6-year-old mare from rural Itabirito, Minas Gerais, Brazil. The mare exhibited nodular cutaneous lesions on all limbs but had no other health issues. Skin and bone marrow samples were collected and analyzed using parasitological and molecular methods targeting the hsp70 gene and ITS1 region. Both L. (V.) braziliensis and L. (L.) infantum were identified, confirming a mixed infectio...
Rey-Conejo R, Toribio RE, Möller S, Müller E, Fores-Jackson P.Insulin dysregulation is a key component of equine metabolic syndrome and is commonly assessed using basal insulin concentrations. Different analyzers may yield variable insulin results, limiting comparability. Objective: To assess the analytical performance of the ADVIA Centaur XPT chemiluminescent immunoassay (CLIA) for equine insulin measurement and to establish adapted decision thresholds based on comparison with a previously used CLIA method. Methods: Precision, linearity, and dilution recovery were assessed for the ADVIA Centaur XPT. A total of 89 equine serum samples submitted for basal...
Neto ME, Curcio BR, Rafael LA, Pivato GM, Silva GC, Souza RP, Mousquer MA, Nogueira CEW.The cesarian section (C-section) is a potential risk factor for retained fetal membranes (RFM) in mares, requiring prompt diagnosis and treatment to enhance outcomes. This study aimed to evaluate the use of umbilical vessel infusion for the treatment of RFM after elective C-section in mares. Ten pregnant criollo type-mares at 315 days of gestation were monitored daily and underwent elective C-section upon readiness for birth. All mares exhibited RFM, with placentas retained beyond three hours careful extraction of the foal by C-section. Those were randomly assigned into two groups: Umbilical v...
Badr C, Arbi M, Souiai O, Larbi I, Nsiri J, Elbehi I, Bouslama Z, Bennour MA, Essaied MS, Ines Khosrof , Chabchoub A, Ben Aoun B, Ghram A, Lachheb J.Equine influenza (EI) is a highly contagious viral respiratory disease affecting equids, with the potential of causing widespread outbreaks across Europe, the Americas, Asia, and other regions of the world. In Tunisia, in the spring of 2021, an EI virus outbreak occurred in a farm housing purebred Arabian horses that exhibited respiratory signs. This outbreak led to a national lockdown on horse movements and the cancellation of equestrian events. A total of 432 serum samples, collected from 2018 to 2021, were tested using ELISA competition assay. In addition, 100 Nasal swabs were collected dur...
Medina-Bolívar AL, Muñoz-Duque JD, Martínez-Aranzales JR.Information regarding Survivin protein expression in the gastric mucosa of equids is scarce. This protein has been associated with functions related to modulating apoptosis and promoting mitosis in epithelial cells and is considered part of gastric cytoprotection mechanisms in humans and mice, maintaining mucosal integrity and regulating cellular renewal. Objective: This study aimed to determine the expression of cytoplasmic and nuclear Survivin in gastric mucosae of equids (horses, donkeys, and mules). Methods: A total of 30 healthy stomachs, 10 from each species, were evaluated using histolo...
Kyari F, Pogu CJ, Mairiga IA, Adamu L.Nematode infections are a significant health concern in horses, causing a range of clinical signs and economic losses. Early detection and diagnosis are crucial for effective treatment and management. Unassigned: Examining the application of the systemic immune Inflammatory index (SII) as a predictor for nematode infections in horses, using platelets count, leucocytes count, and neutrophils count. Unassigned: A cross-sectional study was conducted on 164 horses, consisting of 66 horses with nematode infections and 98 horses without infections. The SII was computed using the platelets count, leu...
El-Shafaey ES, Hamed M, Amin Y, Alkhodair KM, Shousha S, Aljazzar A, El Sebaei MG, Mosbah E.External genitalia swellings represent diagnostic and treatment challenges in equids. Thus, the present study aimed to describe the clinical, histopathological, and treatment outcomes of external genitalia swellings in horses and donkeys. Unassigned: Seventy-five equids (49 horses and 26 donkeys) from 6 months to 8 years were enrolled based on the clinical evidence of external genital swellings. The descriptive details, including sex, age, lesion location, and treatment outcomes, for each case were recorded and analyzed. Unassigned: Twenty forms of external genital swellings were recorded ...
Merari A, Fielding L.To describe patient characteristics, laboratory data, fetal orientation, methods of correction, survival, and treatment in miniature equids with dystocia. Methods: Retrospective study conducted from January 2002 to June 2023. Methods: Equine referral hospital and field service. Methods: Seventy animals with a total of 78 instances of dystocia. Methods: None. Results: Recorded variables included signalment, clinicopathologic data, fetal presentation, correction method, survival to discharge, and complications. The survival of miniature equid mares was 94% (73/78), while survival of foals was 17...
Carroll AT, Reed RA, Perlini M, Clough AE, Rocha M, Moorman VJ.To evaluate the effect of cervical epidural injection of morphine alone and morphine in combination with detomidine on recovery from anesthesia in horses. Methods: Blinded, randomized, crossover, Latin square design. Methods: A group of six healthy adult horses aged 9 ± 3 years and weighing 471 ± 76 kg (mean ± standard deviation). Methods: Horses were administered each of three treatments during a 1 hour general anesthetic with a 4 day washout period. Treatments were: 1) cervical epidural injection of saline 0.011 mL kg (S); 2) morphine 0.1 mg kg (M); and 3) morphine 0.1 mg kg with detomidi...
Majcher AM, Troillet A, Gerlach K, Tönnies PR, Brehm W, Ulrich R.Nine days after a surgical intervention due to an injury of the left hind hoof capsule, a 9-y-old, 538-kg female Wielkopolski horse was found recumbent in its stall with an unplugged permanent intravenous catheter positioned in the left jugular vein. Despite immediate resuscitation attempts, the animal died within minutes. Suspecting venous air embolism, radiographic imaging and detailed postmortem examinations were performed. However, visualization of the heart by radiography was hindered by the animal's body mass and postmortem changes. The autopsy followed a modified Richter method, origina...
Loyd A, Neto R, Caldwell F, Boone L, White A.This study aimed to determine the safety and macroscopic/microscopic effects of fluorescence biomodulation (FBM) on experimentally induced, full-thickness, distal limb wounds in horses.This was an experimental study ( = 6 horses). Two full-thickness wounds were created on both dorsal metacarpi of six adult horses. Each forelimb was randomly allocated to either control (no FBM) or treatment (FBM) and randomly allocated to visual or histological assessment of healing. Wounds were treated within each experimental group every 7 days for four treatments. Fluorescence biomodulation wounds were ...
Amari M, Brioschi FA, Auletta L, Ravasio G.Radiofrequency ablation (RFA) and pulsed radiofrequency (PRF) are non-pharmacological techniques employed in humans for chronic pain, but their veterinary application is unexplored. This pilot study evaluated clinical effects of RFA and PRF in twenty-four horses with chronic distal forelimb lameness. Ultrasound-guided RFA (N = 8; 60-90 °C, 2-8 min) or PRF (N = 16; 42 °C; 12 min) was applied to palmar digital nerves. Lameness was scored (American Association of Equine Practitioners scale) at baseline and monthly for six months (T1-T6). At T2, partial- and non-responders in both groups receive...
Gandini M, Bertone C, Giusto G.Castration remains a common surgical procedure in equids, yet postoperative complications such as hemorrhage, infection, and eventration persist, influencing surgical outcomes. This retrospective study introduced a novel modified semi-closed castration technique aimed at minimizing these complications. Eighty-five sexually intact mature male equids (including horses, ponies, and donkeys) underwent the described inguinal castration procedure under general anesthesia. The technique involved a carefully managed opening and subsequent secure closure of the parietal vaginal tunic, enabling direct i...
Porter MM, Davis DJ, McAdams ZL, Townsend KS, Martin LM, Wilhite C, Johnson PJ, Ericsson AC.Fecal water syndrome (FWS) in horses is characterized by two-phase defecation, including both solid and liquid phases. While satisfactory explanations for FWS are unavailable, bacterial dysbiosis has been suggested as a contributing or causative factor. The objectives of this study were to determine whether fecal bacterial dysbiosis is associated with FWS in horses in the midwestern USA. Fecal samples were collected from horses with FWS and from unaffected horses at the same location. In total, 16S rRNA amplicon libraries produced from fecal bacterial DNA were sequenced using the Illumina sequ...
Kovarikova S, Blahova J, Steffenova V, Vaskova N, Jahn P.Currently, there is relatively little published information on the urine protein-to-creatinine (UPC) ratio in horses, a parameter commonly used in dogs and cats. The aim of this study was to determine the reference range of UPC in urine samples of apparently healthy horses and to assess the influence of age and sex. Urinalysis and the determination of urinary protein and creatinine concentrations and ratios were performed. A total of 118 urine samples from apparently healthy horses were included in the study: 10 from foals younger than 6 months and 108 from horses older than 1 year. The median...
