Veterinary research in horses encompasses the study of diseases, health management, and medical treatments specific to equine species. This field investigates various aspects of horse health, including infectious diseases, metabolic disorders, and musculoskeletal conditions. Researchers focus on understanding the pathophysiology of equine ailments, developing diagnostic tools, and evaluating therapeutic interventions. The study of horse health also involves examining preventive measures such as vaccination protocols and nutritional management to promote overall well-being. This page collects peer-reviewed research studies and scholarly articles that explore the diverse areas of veterinary science related to horses, providing insights into disease mechanisms, treatment strategies, and advancements in equine healthcare.
Atkinson JP.1. The globulins of both normal and diphtheria antitoxic serum exhibit chemically toward reagents the same reactions, being precipitated by magnesium sulphate and split up into fractions in precisely the same way. 2. All of the diphtheric antitoxic power of both normal and immunized serum is always carried by the globulin and its fractional precipitates. 3. During the fractional precipitation of the serum globulin of horses immunized from diphtheria toxin and horses not immunized from diphtheria toxin, some of the globulin is lost, likewise at the same time some of the antitoxic power of the g...
Bertin FR, van Eps AW, de Tonnerre DJ, Kulp JC, Stefanovski D.Dexamethasone is used to experimentally induce insulin resistance; however, its impact on insulin secretion is unclear. This study aimed to assess the responses to oral carbohydrate challenges in dexamethasone-treated horses. Unassigned: 8 healthy Standardbreds received 0.08 mg/kg of dexamethasone IM every 48 hours for 14 days in June 2022 (winter in the Southern hemisphere). Oral glucose tests (OGT) were conducted before treatment (day 1) and on days 8 and 15. Glucose, insulin, triglycerides, total and active glucagon-like peptide-1 (tGLP-1 and aGLP-1) and glucose-dependent insulinotropic pol...
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...
Hoerdemann M, Sahoo DK, Allbaugh RA, Kubai MA.To assess if an affordable, commercially available 275 nm ultraviolet C (UV-C) device can inhibit fungal pathogens associated with equine keratomycosis and to establish the optimal exposure time/dose required in vitro. Methods: Fungal inhibition zone surface areas of isolates from two fungal genera (Aspergillus and Fusarium spp.) were compared in triplicates after UV-C exposure at distances of 10, 15, and 20 mm with single or repeat doses (4 h apart) of 5, 10, 15, or 30 s duration after 24, 48, and 72 h of incubation. Inhibition zones were microscopically assessed, and regrowth chec...
Spacek SG, Hernández-Avilés C, Ramírez-Agámez L, Pearson M, Love CC.Cryopreservation of stallion epididymal sperm has become a common clinical procedure after routine castration, euthanasia, or acute death. Unique features of epididymal sperm compared to ejaculated sperm include the requirement to remove sperm from the cauda epididymis, lack of exposure to seminal plasma, and potential recovery of large sperm numbers. In this study, the effect of the flushing technique (Extender (INRA) vs. AIR), freezing extender (LE, CMLE, MFR5, CFR5, or BOTU), and the concentration at which sperm are cryopreserved (200, 400, or 800 × 10 sperm/mL) on post-thaw epididymal s...
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 ...
Jones CJP, Wilsher S, Aplin JD.We report a lectin histochemical study of oviductal ampulla and isthmus of thirteen mares euthanised at anestrus (1), estrus (5), 1-day post-ovulation (5) or diestrus (2). Staining with a panel of 5 lectins recognizing N-Acetylgalactosamine (GalNAc) residues revealed mosaicism in glycan expression in some specimens of ampulla and isthmus, peaking at estrus and 1-day post-ovulation (ov+1). In the ampulla, this presented as positively stained areas of both ciliated and non-ciliated cells in otherwise negatively-stained ampullae, ranging from small foci (diestrus) to areas up to 200 microns in le...
Volding DM, Flores-Ahlschwede P, Cramer MJ, Landrock KK, Sayre KC, Welsh TH, Bordin AI, Piccione J, Cohen ND.To determine the effects of transfusion of Rhodococcus equi hyperimmune plasma (REHIP) on serum electrolyte and protein concentrations in neonatal foals. Unassigned: A prospective observational study of 355 privately owned Thoroughbred foals from 13 farms in New York and cross-sectional study of REHIP samples. Blood was collected immediately before and after transfusion of either 1 or 2 L of REHIP to foals, and serum samples were separated and frozen until tested for concentrations of sodium (Na), potassium (K), chloride (Cl), total protein (TP), albumin, and globulins. Samples (n = 90) of REH...
Bailey CS, Beachler TM, Mochel JP, Wulf LW, Yaeger M, Kundu D, Withowski K, Papich MG.Despite their widespread clinical use, there is limited pharmacokinetic data for many equine intrauterine antimicrobials. This study aimed to measure the concentration of gentamicin and penicillin in the uterine fluid of mares following infusion of either a standard (PPGent) or long-acting (LA-PPGent) compounded formulation. We hypothesized that both formulations would result in therapeutic concentrations, with total concentrations sustained for longer using the long-acting formulation. Mares were administered 2400 mg of procaine penicillin and 200 mg of gentamicin via a single intrauterin...
Ishimaru M, Kume K, Murase H, Sato F, Matsui A, Ohmura H, Taya K.Thoroughbreds born early in the year are believed to have an advantage in racing. However, the development of endocrine functions in early-born foals in the cold winter climate is unclear. The present study was conducted to elucidate the effect of birth month on the development of endocrine function in Thoroughbred foals born from February to May in Hokkaido by comparing hypothalamic-pituitary axis, adrenal and thyroid functions from birth to 24 weeks of age. Eighty-seven Thoroughbred foals were used to compare the changes in circulating luteinizing hormone (LH), follicle-stimulating hormone (...
Lection J, Schnobrich M, Wagner B, Byron M, Back B, Rollins A, Castro Alves RF, Cheong SH, Diel de Amorim M.To evaluate inflammatory cytokine and chemokine concentrations in endometrial samples collected by cytobrush or swab as a potential screening diagnostic marker for equine endometritis. Unassigned: 88 mares had endometrial samples collected, which included cytobrush, swab, and/or biopsy. Clinical reproductive records, reproductive ultrasound examination, endometrial cytology and culture results, and biopsy grading score were recorded. Fluorescent bead-based multiplex assays for the inflammatory markers interferon-γ, interferon-α, IL-1β, IL-4, IL-10, IL-17A, soluble CD14, tumor necrosis facto...
Maria Feitosa Ribeiro L, Bersot Gomes JV, Hernando Ortiz Vega W, da Silva Alves A, Netto Machado M, Junio Wutke L, Raquel Quirino C....Stallion breeding is mostly based on desirable phenotypic traits, with little consideration for semen quality. Objective: To identify relationships among semen parameters in stallions using a non-invasive, integrative approach across summer and winter seasons. Methods: Twenty-four stallions were evaluated, in which semen collections, testicular thermography, and Doppler velocimetry of the testicular artery by Doppler ultrasonography were performed, in addition to the measurement of physiological, environmental, and heat stress parameters, both in winter (coat weather) and summer (T-shirt weath...
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...
Alves LSS, Hasuda AL, Giordano LGP, Frederico I, Dos Santos IH, Pereira PFV, Lisbôa JAN, Flaiban KKMDC.This study investigated isolation of equine neutrophils and the assessment of their antioxidant function using the nitroblue tetrazolium (NBT) reduction test, an indicator of reactive oxygen species (ROS) activation. The objective was to test the viability of neutrophils isolated from equine whole blood and their ability to undergo respiratory burst, comparing the results with whole blood. The hypothesis tested was that isolation of equine neutrophils allows for effective functional evaluation, even after isolation process, with no significant differences between whole blood and isolated cells...
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...
Sosa-Portugal S, Dale L, Devaney J, Sharp A, Malalana F, Timofte D.The "ESKAPE" bacteria include a group of organisms known for their multidrug resistance and potential association with nosocomial infections in human and veterinary hospitals. Objective: This study aimed to evaluate the effectiveness of steam cleaning in reducing the number of ESKAPE organisms on environmental surfaces from the stables of an equine veterinary referral hospital. Methods: Environmental sampling was performed at two timepoints (pre- and post-steam cleaning) on smooth metallic doors and rough rubber stable walls. Microbiological culture targeted ESKAPE organisms and Escherichia co...
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...
Ramírez-Agámez L, Hernández-Avilés C, Samper JC, Love CC.Intracytoplasmic sperm injection (ICSI) using frozen/thawed (F/T) stallion sperm is a common procedure in the equine breeding industry. Historically, sex-sorted (SS) F/T stallion sperm has yielded lower cleavage (<30 %) and blastocyst rates (<5 %) after ICSI when compared to non-sorted (NS) F/T sperm. Recently, a new technology for sperm sex-sorting (Genesis III) has been validated by a commercial company. In Experiment 1, the post-thaw quality between NS-F/T and SS-F/T stallion sperm produced with this technology was compared. The post-thaw sperm motility was higher in NS-F/T (41 %) than i...
Graham AE, Colgate VA, Floyd EF.Geographical specific data is required to guide empirical antimicrobial selection in equine neonates. Objective: Evaluate antibiograms and survival in foals from a United Kingdom (UK)-based hospital to guide antimicrobial selection. Methods: Blood and synovial fluid samples from 208 foals ≤ 30 days old admitted to Rossdales Equine Hospital from 2018 to 2023. Methods: Retrospective cohort study. Antimicrobial susceptibility was assessed by disc diffusion method. Bacterial culture and susceptibility and foal survival were recorded. The effects of the presence of positive culture or multi...
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...
Hobbs KJ, Ueda Y, Le Sueur ANV, Cooper BL, Burke MJ, Sheats MK.To determine the effect of hemoperfusion with a polymer-based column on systemic cytokine concentrations and neutrophil dysfunction in lipopolysaccharide-treated horses in vivo. Unassigned: 6 university-owned horses received 60 ng/kg lipopolysaccharide, IV, as a bolus and then 60 ng/kg, IV, as a constant rate infusion over 1 hour. Endotoxemia was confirmed by clinical signs and neutropenia. In a crossover model that was completed from January 2024 through July 2024, hemoperfusion was performed for 4 hours with either a sham or polymer column. Blood was collected at 5 time points over a 72-hour...
Martin de Bustamante MG, Plummer CE, Caddey B, Gomez DE.Information regarding the impact of topical antibiotics with or without corticosteroids on the microbiota of the horses' eyes is limited. This study aimed to describe the bacterial ocular surface microbiota in healthy horses and evaluate the effect of topical antibiotics or antibiotic-corticosteroid medication on the ocular surface microbiota. Unassigned: This was a prospective, randomized, longitudinal, blinded study in which one eye of 12 horses was treated 3 times daily for 7 days with neomycin, polymyxin B and bacitracin ophthalmic ointment ( = 6) or neomycin, polymyxin B and dexametha...
Bannai H, Kambayashi Y, Kume K, Takebe N, Endo Y, Kawanishi N, Nemoto M, Tsujimura K.The endemic situation of respiratory disease caused by equine herpesvirus type-1 (EHV-1) and type-4 (EHV-4) was investigated in a training facility for Thoroughbred yearlings in Japan. Vaccination typically starts in mid-September or early October-only after all yearlings have arrived-leaving those introduced earlier unprotected. To bridge this immunity gap, a revised vaccination program that started earlier was implemented. In 2021-2022 and 2022-2023, yearlings were allocated to three groups according to their introduction dates. Each group received a live EHV-1 vaccine (Equi N Tect ERP, Niss...
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...
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...
Hopster K, Soares JHN, Levine D, Ortved K, Driessen B, Araos J.Flow-controlled expiration (FLEX) has been shown to significantly enhance oxygenation in horses under laboratory conditions. Objective: This study aims to corroborate these findings by evaluating the effects of FLEX on gas exchange in a randomised clinical trial involving a large population of clinical horses undergoing orthopaedic surgery. Methods: Prospective randomised clinical trial. Methods: A total of 406 healthy adult horses scheduled for elective orthopaedic procedures were recruited for this prospective clinical trial. Horses were randomly assigned to FLEX or VCV (volume-controlled ve...
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...
Cormier KV, Fontenot RL, Eddy A, Williams ML, Wills RW, Jumper WI, Mochal-King CA.The objective of the study was to evaluate effects of intra-articular decellularized porcine amnion/chorion suspension (dPACLS) in horses. Methods: Controlled, randomized, prospective study. Methods: A total of 10 adult horses. Methods: One randomly selected radiocarpal joint (RCJ) was injected with a high dose (HD) of 50 mg (n = 5) or low dose (LD) of 5 mg of dPACLS (n = 5). The contralateral RCJ received saline as control. Systemic serum amyloid A (SAA), synovial fluid analysis (including SAA) and subjective lameness evaluation were performed prior to injection (time 0) and 24, 4...
Carroll AT, Reed RA, Berghaus LJ, McNabney D, Knych HK.To investigate the effect of cannabidiol (CBD) on thermal and mechanical thresholds and physiologic variables in horses. Unassigned: 6 horses (3 geldings and 3 mares) were enrolled in a prospective, randomized, masked crossover design from March 18 through May 3, 2025. Horses received 3.48 mg/kg CBD oil or placebo (sesame oil) orally every 24 hours for 3 days. Thermal and mechanical thresholds were determined at baseline and 4 and 12 hours after treatment administration on each day. Physiologic variables, including heart rate, respiratory rate, and rectal temperature, were recorded at the same...
