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.
Richardson LM, Gordon J, Davila C, Chamoun-Emanuelli AM, Zdyrski C, Whitfield-Cargile CM.Gastrointestinal (GI) disease is a major cause of morbidity and mortality in horses, with disruption of the intestinal epithelial barrier playing a central role in disease pathogenesis. A deeper understanding of the molecular and functional properties of the equine intestinal barrier is essential to improve diagnostics and therapeutics. While intestinal organoids have emerged as a promising tool for modeling GI physiology and disease, equine-specific data remain limited. Existing studies vary in methodology and often lack functional characterization, particularly across different intestinal re...
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...
Choi Y, Rosanowski SM, Parkin TD.To identify risk factors associated with complete humerus fractures in Thoroughbreds in South Korea. Unassigned: A retrospective case-control design with multivariable logistic regression was used. This study included 131 Thoroughbreds diagnosed with complete humerus fractures following racetrack activity between 2009 and 2022 (inclusive). Additionally, 660 healthy Thoroughbreds (699 observations) with at least 1 racetrack activity during the same period were included as controls. Unassigned: A total of 8 variables were associated with the risk of complete humerus fractures. Notably, horses wi...
Korac L, St George L, MacNicol J, McCrae P, Jung L, Golestani N, Karrow N, Cánovas A, Pearson W.Low-dose intra-articular injection of recombinant equine interleukin-1β (reIL-1β) may offer a useful model for studying early onset or subclinical joint inflammation in horses. This pilot study aimed to determine the lowest intra-articular dose of reIL-1β required to produce biochemical evidence of synovitis, and to correlate synovitis biomarkers with functional, upper-body asymmetry parameters. Saline (control) and 50, and 75 ng reIL-1β were injected into the left or right intercarpal joint of three ( = 3) horses in a three-way crossover design. Synovial fluid was collected by aseptic art...
Ganbaatar O, Batbaatar V, Kimura T, Ganzorig S, Tseren-Ochir EO, Suzuki Y, Takai S.ELISA antibody titers against Rhodococcus equi strain ATCC 6939 were measured in serum samples collected from 644 horses aged 1-21 years at 13 provinces and the capital of Mongolia, of which 631 (98%) samples showed values of approximately zero. The mean antibody titers in the 14 areas ranged from -0.08 to -0.01. Nine samples (1.4%) exhibited titers of 0.1-0.2, and surprisingly, four horses (0.6%) each aged 2, 5, 8, and 9 years demonstrated positive values in the range of 0.3-0.8. Considering the age resistance characteristic of this disease, the positive horses were hypothesized to exhibit no...
Mlyneková E, Zaťko S, Halo M, Imrich I, Halo M.This study aimed to examine the seasonal dynamics of non-structural carbohydrates in pasture and their relationship to metabolic indicators in horses with a history of laminitis. Thirty Hucul mares were divided into a laminitis group (LG, = 15) and a control group (CG, = 15). Insulin, glucose, fructosamines concentrations and body weight were monitored during four sampling periods (S0-S3), while pasture variables were analyzed during three periods (S1-S3). The concentration of water-soluble carbohydrates was highest in May (126.8 g/kg DM) and measured lower in October (57.9 g/kg DM), while s...
Morales CJ, Sykes BW, McKemie DS, Kass PH, Knych HK.Current treatment options for equine gastric ulcer syndrome (EGUS), such as omeprazole-a proton pump inhibitor (PPI)-have notable limitations, including the need for administration on an empty stomach. Potassium-competitive acid blockers (P-CABs), such as vonoprazan, are a newer class of acid suppressants that offer several advantages over PPIs in humans and may provide similar benefits in horses. Objective: To describe the pharmacokinetics and effect of a single oral dose of vonoprazan on intragastric pH in horses. We hypothesised that vonoprazan would follow linear kinetics across the doses ...
Ferreira C, Palhares MS, de Melo UP, Leme FOP, Maranhão RPA, Garcia HC, Gheller VA.Starvation and nutritional support clinically influence horses, particularly during the treatment of gastrointestinal diseases and post-surgical recovery. In this study, we aimed to evaluate the effects of different nutritional strategies on the endocrine response of horses subjected to exploratory laparotomy followed by food deprivation. Sixteen healthy adult horses were randomly allocated into four groups (n=4) based on treatments: enteral fluid therapy without (ENTFL) or with glutamine (ENTGL), and parenteral fluid therapy with glucose (PARFL) or total parenteral nutrition with glutamine (P...
Dagenais A, Juette T, Benoit-Biancamano MO, Vanore M.(1) Context: Squamous cell carcinoma (SCC) is the most prevalent ocular neoplasm in horses, with a reported 45% recurrence rate when managed by surgery alone. (2) Objective: To evaluate the effect of adjunctive cisplatin biodegradable beads (CBBs) on recurrence rates of equine corneolimbal squamous cell carcinoma (SCC) and to document associated adverse effects. (3) Methods: Seventeen cases of histopathologically confirmed corneolimbal SCC in horses were retrospectively identified. Masses were surgically excised by keratectomy and/or conjunctivectomy under general anesthesia, followed by impla...
Medina-Bautista F, Morgaz J, Quirós-Carmona S, Caravaca-Paredes ME, Navarrete-Calvo R, Medina ALS, Gómez-Villamandos R, Granados MDM.Standing sedation in horses provides immobilization and analgesia for surgery while avoiding the high risks of general anesthesia. Ketamine at subanesthetic doses may enhance sedation and reduce xylazine requirements, but evidence in clinical settings is limited. In a randomized blinded trial, we evaluated whether adding a low-dose ketamine infusion could reduce the xylazine dose required for effective sedation during standing ventriculocordectomy and laryngoplasty. Fifty-one horses were randomly assigned to sedation with xylazine alone (SX group) or xylazine plus ketamine (KX group) in a cont...
Shahid MA, Guitart AS, Bertin FR, Simon O, Ceusters J, Serteyn D, Whitworth DJ.A minimally invasive microbiopsy-based method for the isolation of mesenchymal stem cells (MSCs) from equine skeletal muscle (M-MSCs) provides a readily accessible source of MSCs for clinical applications. We examined the expression of genes associated with immunomodulation and anti-inflammatory pathways, in addition to those of growth factors and the major histocompatibility complex (MHC) molecules I and II, at constitutive levels and after priming with inflammatory cytokines, an immunostimulant, and heat-shocking. While there was notable variation between the M-MSCs from each of the horses i...
Kirmse L, Thieme K, Doherr MG, Eule JC.To evaluate different laboratory procedures for determining the etiologic diagnosis of equine recurrent uveitis regarding intraocular infection with Leptospira spp. and to establish a diagnostic guideline. Methods: Eighty horses with a history of ERU were ophthalmologically examined. Serum and aqueous humor were collected. Total protein, albumin level, and MAT against Leptospira spp. were evaluated on serum and aqueous humor. PCR for Leptospira spp., EHV-1 and -4 was performed on aqueous humor. Goldmann-Witmer coefficient (GWC) and C-value (CC) were calculated based on MAT. In 42 cases, an add...
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, ...
In horses, heat exposure modulates the hypothalamic-pituitary-adrenal axis, autonomic nervous system, and hypothalamic-pituitary-thyroid axis to maintain body temperature and prevent excessive heat accumulation. However, during strenuous exercise under hot and humid conditions, heat production may exceed dissipation, leading to heat stress, anhidrosis, heat stroke, or brain damage. Unassigned: Incremental field standardized exercise tests (fSETs) provide a reliable approach to assess training and fitness levels. Six Arabian horses from Italia Endurance Stable and Academy were monitored during ...
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...
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...
Cooper CJ, Arroyo LG, Hammermueller JD, Botts MM, Pearl DL, Wootton SK, Lillie BN.Equine herpesvirus-1 (EHV-1) is ubiquitous in the horse population, but prevalence estimates have ranged from 3 to 88% depending on the population and method of sampling. No prevalence studies have been carried out in Ontario, Canada. The objective of this study was to measure the prevalence of EHV-1 shedding in healthy broodmares in Ontario. A total of 381 mares from 42 farms in Ontario were sampled, including pregnant and barren broodmares. Samples were collected from the nose, vagina, and blood of each mare up to 6 times from December 2016 through October 2017 using a cross-sectional study ...
Pécresse B, Moiroud C, Hanne-Poujade S, Hatrisse C, De Azevedo E, Coudry V, Jacquet S, Audigié F, Chateau H.Locomotor disorders involving the spine are a major cause of impaired performance and early retirement in sport horses. Swimming is increasingly incorporated into rehabilitation protocols, but its effects on spinal biomechanics remain poorly understood. This prospective study evaluated changes in thoracolumbar mobility in sixteen sport horses diagnosed with cervical or thoracolumbar axial musculoskeletal lesions over a 12-week rehabilitation program comprising 4 weeks of land-based training followed by 8 weeks during which swimming sessions were incorporated three times per week. Weekly measur...
Jastrzębska E, Dobbek D, Pawłowska A.Back pain in horses is a frequent musculoskeletal issue that affects performance and welfare. Magnetotherapy has been proposed as a complementary, non-invasive treatment to reduce pain and support soft tissue recovery, but studies in horses remain limited. This pilot study aimed to evaluate the effects of low-frequency pulsed magnetic field therapy on horses with hypersensitivity to palpation along the longissimus dorsi muscle. Four recreational horses participated in a 10-session magnetotherapy program, with changes assessed using palpation, neck flexibility tests, heart rate measurements and...
Almaqhawi AA, El-Jalii IM, Al-Sabi MNS, Al-Ali A, Khalid AM, Abduljawad M, Shawaf T.Equine babesiosis is a widespread protozoan disease in Saudi Arabia. The most common finding of clinical babesiosis is splenomegaly, which can be detected using non-invasive splenic ultrasonography. Unassigned: This study aimed to investigate changes in the spleen size in horses infected with babesiosis using ultrasonography before and after treatment. Unassigned: This study employed 15 male and female Arabian horses. Each animal was examined clinically for clinical signs, and blood samples were collected in plain tubes to detect antibodies against . The spleens of healthy and affected horses ...
Lopes A, Aitkin E, Louro LF.Post-anaesthetic colic (PAC) is a complication in horses undergoing general anaesthesia (GA). Various preoperative feeding strategies are used in equine practice, yet their impact on PAC remains unclear. Objective: To identify perioperative risk factors associated with PAC and evaluate the influence of preoperative fasting on PAC prevalence and faecal output. Methods: Retrospective cohort study. Methods: Medical records of horses undergoing non-abdominal surgery under GA were reviewed. Horses were categorised into fasted and non-fasted groups based on their pre-anaesthetic feeding regimen. Mul...
Seeger MG, de Vargas APC, Vogel FSF, Cargnelutti JF.Streptococcus equi subsp. equi (S. equi) is the etiological agent of strangles, a contagious equine disease characterized by lymph node abscess and respiratory complications. To clarify the epidemiology and virulence factors of isolates, this study demonstrated phenotypic and genotypic differences between S. equi obtained from nasal secretions and lymph node aspirates of clinical strangles cases. Additionally, circulating alleles were differentiated through sequencing of the 5' end of the seM gene. A total of 23 clinical isolates collected from horses with strangles over the past decade were a...
Zedler S, Jukic C, van Eps A, Stefanovski D, Genton M, Rossignol F.To compare the biomechanical properties of a three-dimensional (3D) printed titanium plate and spacer (3DM) and a 4.5 mm broad locking compression plate (LCP) for intervertebral fusion of C4-C5 in the horse. Methods: Ex vivo experimental study. Methods: Twenty-four equine cadaveric cervical spines. Methods: Twenty-four cadaver equine cervical spines were randomly assigned to ventral intervertebral fusion with either 3DM (n = 12) or LCP (n = 12) at C4-C5. Four-point bending tests were performed in flexion (3DM n = 6, LCP n = 6) and extension (3DM n = 6, LCP n = 6) in a sin...
Ekstrand C, Michanek P, Hernlund E, Gehring R, Spjut K, Salomonsson M.There has been a growing interest in the use of cannabinoids in horses in recent years. Several studies have reported on the pharmacokinetics of cannabidiol (CBD) in horses. However, cannabidiolic acid (CBDA) has received less attention, despite limited evidence suggesting clinically beneficial effects in other species. Horses were administered 3 mg/kg of CBD, 3 mg/kg of CBDA, and a placebo per os in a crossover design, with a one-week washout period between treatments. Plasma and urine samples were collected and analyzed using ultra high-performance liquid chromatography coupled to tandem...
Muderspach ND, Daucke R, Nielsen MW, Scoggin KE, Fedorka CE, Miller LMJ, May MG, Troedsson MHT, Ferreira-Dias G, Agerholm JS, Schoof EM....Endometrial fibrosis leads to subfertility when periglandular fibrosis impairs endometrial gland function. Identifying distinct protein expressions in mares suffering from this condition is essential for understanding the pathogenesis and developing treatments to delay fibrotic progression. To gain a better understanding of protein dynamics underlying this condition, Data-Independent Acquisition Mass Spectrometry was utilized to comprehensively characterize and compare the equine endometrial and plasma proteome from mares with different severities of endometrial fibrosis. Mares in diestrus wer...
Mège M, Bonsergent C, Viry L, Dhune M, Lecollinet S, Malandrin L.Equine piroplasmosis is a major tick-borne horse disease, caused by the intracellular development of piroplasms (Theileria equi sensu lato and Babesia caballi), with significant economic and sanitary consequences. In 2024, 203 blood samples were collected in Guadeloupe (Caribbean) from asymptomatic horses. Using an 18S rRNA nested PCR (nPCR) specific for each equine genus parasite, 79 samples tested positive for Theileria equi and 9 for Babesia caballi, resulting in respective prevalence of 38.9% and 4.4%. Three horses were co-infected. For B. caballi, 18S rRNA sequence analysis revealed the p...
Brito LFC, Linardi RL, Rosales LAS, Balamurugan NS, Hernández-Avilés C, Ramírez-Agámez L.Efficient use of stallion semen in liquid state is limited by its relatively short shelf-life. A chemically defined extender (Beyond) is now available for long-term liquid semen preservation. The objectives of the present study were to compare Beyond with milk extenders for the preservation of semen at two temperatures, and to evaluate fertility of semen cooled for 4-8 days before artificial insemination. Semen was processed using different extenders: milk, cholesterol (BotuSemen Special); milk-based (INRA 96); and Beyond. Sperm motility, membrane and acrosome integrity, and chromatin struct...
Motta D, Pedrosa J, Lilenbaum W.Leptospirosis is a zoonotic disease caused by pathogenic bacteria of the genus Leptospira. A lesser-known form, equine genital leptospirosis (EGL), has been identified as a chronic and often silent infection involving the colonisation of the mare's genital tract. Despite its potential impact, EGL remains underdiagnosed and poorly understood, particularly in its association with reproductive inefficiency. This study showed the presence of Leptospira spp. DNA by lipL32-PCR in the genital tract of mares with a history of reproductive disturbances. Cervicovaginal mucus samples were collected from ...
Hain AM, Tretow M, Bienert-Zeit A.Outside of Iceland, the Icelandic horse is prone to the development of Equine Odontoclastic Tooth Resorption and Hypercementosis (EOTRH). The aim of this study was to determine the radiographic prevalence and clinical signs of EOTRH in elderly horses (≥15 years) in Iceland. The rostral oral cavity of 170 horses (aged 15-30 years) was examined clinically. In addition, husbandry and nutritional management history was recorded by use of a questionnaire. Radiographs (2-4 views) of 188 horses were evaluated, findings were categorized by numerical staging of the condition and collated with clinica...
Verna M, Amitrano FN, Boeder ZJ.To assess the clinical impact of the cricoarytenoideus dorsalis (CAD) myectomy in the short- and long-term postoperative abduction grade in racehorses. Unassigned: Records from horses presented for surgical treatment of recurrent laryngeal neuropathy from January 2019 through December 2023 were divided into 2 groups: horses that received standard prosthetic laryngoplasty and horses that received a complete myectomy of the CAD (modified myectomy laryngoplasty). Outcomes were compared through endoscopic evaluation after anesthetic recovery, both short term (7 to 10 days) and long term (80 to 90 ...
McCarthy HE, Bara JJ, Brakspear K, Singhrao SK, Archer CW.A chondrocyte progenitor population isolated from the surface zone of articular cartilage presents a promising cell source for cell-based cartilage repair. In this study, equine articular cartilage progenitor cells (ACPCs) and equine bone marrow-derived stromal cells (BMSCs) were compared as potential cell sources for repair. Clonally derived BMSCs and ACPCs demonstrated expression of the cell fate selector gene, Notch-1, and the putative stem cell markers STRO-1, CD90 and CD166. Chondrogenic induction revealed positive labelling for collagen type II and aggrecan. Collagen type X was not detec...
Baldacchino F, Desquesnes M, Mihok S, Foil LD, Duvallet G, Jittapalapong S.Tabanids are nuisance pests for people and livestock because of their painful and irritating bite, persistent biting behavior, and blood ingestion. About 4400 tabanid species have been described; they are seasonally present in all kinds of landscapes, latitudes, and altitudes. High populations have a significant economic impact on outdoor activities, tourism, and livestock production. Tabanids are also vectors of animal disease agents, including viruses, bacteria and parasites. However, tabanids have received little attention in comparison with other hematophagous Diptera. Here, we highlight t...
Wong K, van der Weyden L, Schott CR, Foote A, Constantino-Casas F, Smith S, Dobson JM, Murchison EP, Wu H, Yeh I, Fullen DR, Joseph N, Bastian BC....Mucosal melanoma is a rare and poorly characterized subtype of human melanoma. Here we perform a cross-species analysis by sequencing tumor-germline pairs from 46 primary human muscosal, 65 primary canine oral and 28 primary equine melanoma cases from mucosal sites. Analysis of these data reveals recurrently mutated driver genes shared between species such as NRAS, FAT4, PTPRJ, TP53 and PTEN, and pathogenic germline alleles of BRCA1, BRCA2 and TP53. We identify a UV mutation signature in a small number of samples, including human cases from the lip and nasal mucosa. A cross-species comparative...
Love S, Murphy D, Mellor D.Cyathostomes are now the principle parasitic pathogen of the horse: a remarkable transformation during the last 25 years from virtual obscurity to focus of attention in equine parasitology. This rise to prominence coincides with the marked decrease in prevalence of large strongyle infections as a result of widespread use of modern anthelmintic compounds. On the basis that strongyle-associated diseases continue to commonly occur in the absence of these large strongyle species, clinical attention has turned to the pathogenicity of cyathostomes. Although many horses harbour burdens of tens of tho...
Chindera K, Mahato M, Sharma AK, Horsley H, Kloc-Muniak K, Kamaruzzaman NF, Kumar S, McFarlane A, Stach J, Bentin T, Good L.To combat infection and antimicrobial resistance, it is helpful to elucidate drug mechanism(s) of action. Here we examined how the widely used antimicrobial polyhexamethylene biguanide (PHMB) kills bacteria selectively over host cells. Contrary to the accepted model of microbial membrane disruption by PHMB, we observed cell entry into a range of bacterial species, and treated bacteria displayed cell division arrest and chromosome condensation, suggesting DNA binding as an alternative antimicrobial mechanism. A DNA-level mechanism was confirmed by observations that PHMB formed nanoparticles whe...
Rubin CT, Lanyon LE.Galileo (1638) observed that "nature cannot grow a tree nor construct an animal beyond a certain size, while retaining the proportions which suffice in the case of a smaller structure". However, subsequent measurement has shown that limb bone dimensions are scaled geometrically with body size (Alexander et al., 1979a), and that the material properties of their constituent bone tissue are similar in animals over a wide range of body weight (Sedlin & Hirsch, 1966; Yamada, 1970; Burstein et al., 1972; Biewener, 1982). If, as suggested in previous scaling arguments (McMahon, 1973; Biewener, 19...
Xu X, Arnason U.The sequence of the mitochondrial (mt) DNA of the horse (Equus caballus) was determined. The length of the sequence presented is 16,660 bp. This figure, however, is not absolute due to pronounced heteroplasmy caused by variable numbers of the motif GTGCACCT in the control region of different molecules. Boundaries of the 13 peptide-coding genes were determined by the presence of start and stop codons, and by analogy with other eutherian mtDNAs. Three genes (COIII, NADH3 and NADH4) were not terminated by a stop codon. Comparison among the peptide-coding genes of the horse and eight other mammals...
Hu S, Vincenz C, Buller M, Dixit VM.Molluscum contagiosum virus proteins MC159 and MC160 and the equine herpesvirus 2 protein E8 share substantial homology to the death effector domain present in the adaptor molecule Fas-associated death domain protein (FADD) and the initiating death protease FADD-like interleukin-1beta-converting enzyme (FLICE) (caspase-8). FADD and FLICE participate in generating the death signal from both tumor necrosis factor receptor-1 (TNFR-1) and the CD-95 receptor. The flow of death signals from TNFR-1 occurs through the adaptor molecule tumor necrosis factor receptor-associated death domain protein (TRA...
Savini G, Afonso A, Mellor P, Aradaib I, Yadin H, Sanaa M, Wilson W, Monaco F, Domingo M.Epizootic haemorrhagic disease (EHD) is an infectious non-contagious viral disease transmitted by insects of the genus Culicoides which affects wild and domestic ruminants. The causative agent, the epizootic haemorrhagic disease virus (EHDV), belongs to the family Reoviridae, genus Orbivirus and shares many morphological and structural characteristics with the other members of the genus such as bluetongue, African horse sickness and equine encephalosis viruses. In recent years EHD outbreaks have been reported in countries bordering the European Union. They caused disease in cattle and severe r...
Steele KE, Twenhafel NA.The encephalitides caused by Venezuelan (VEEV), eastern (EEEV), and western (WEEV) equine encephalitis viruses are important natural diseases of horses and humans and potential agents of biowarfare or bioterrorism. No licensed vaccines or specific therapies exist to prevent or treat human infections with VEEV, EEEV, or WEEV. Well-characterized animal models are needed to support the development of such medical countermeasures under the United States Food and Drug Administration's "Animal Rule." This review focuses on the pathological features and pathogenetic mechanisms of these alphaviral enc...
Thorpe CT, Streeter I, Pinchbeck GL, Goodship AE, Clegg PD, Birch HL.Little is known about the rate at which protein turnover occurs in living tendon and whether the rate differs between tendons with different physiological roles. In this study, we have quantified the racemization of aspartic acid to calculate the age of the collagenous and non-collagenous components of the high strain injury-prone superficial digital flexor tendon (SDFT) and low strain rarely injured common digital extensor tendon (CDET) in a group of horses with a wide age range. In addition, the turnover of collagen was assessed indirectly by measuring the levels of collagen degradation mark...
Schmiedel J, Falgenhauer L, Domann E, Bauerfeind R, Prenger-Berninghoff E, Imirzalioglu C, Chakraborty T.Multiresistant Gram-negative bacteria producing extended-spectrum β-lactamases (ESBLs) are an emerging problem in human and veterinary medicine. This study focused on comparative molecular characterization of β-lactamase and ESBL-producing Enterobacteriaceae isolates from central Hesse in Germany. Isolates originated from humans, companion animals (dogs and cats) and horses. Results: In this study 153 (83.6%) of the human isolates (n = 183) and 163 (91.6%) of the animal isolates (n = 178) were confirmed as ESBL producers by PCR and subsequent sequencing of the PCR amplicons. Predomin...
Johnston GM, Eastment JK, Wood J, Taylor PM.To document the equine perioperative mortality rate and to highlight any factor associated with an increased risk of death up to 7 days after anaesthesia. Methods: A prospective observational epidemiological multicentre study. Methods: Data were recorded from all equidae undergoing general anaesthesia in 62 clinics. Power calculations indicated that 45 000 cases were required to detect the significance of important variables. Details of each horse, operation, anaesthetic agents and clinic personnel were recorded. Outcome at 7 days was recorded as: alive, put to sleep (PTS) or dead. Data were a...
Wathan J, Burrows AM, Waller BM, McComb K.Although previous studies of horses have investigated their facial expressions in specific contexts, e.g. pain, until now there has been no methodology available that documents all the possible facial movements of the horse and provides a way to record all potential facial configurations. This is essential for an objective description of horse facial expressions across a range of contexts that reflect different emotional states. Facial Action Coding Systems (FACS) provide a systematic methodology of identifying and coding facial expressions on the basis of underlying facial musculature and mus...
Vidal MA, Walker NJ, Napoli E, Borjesson DL.Mesenchymal stem cells (MSCs) from adult and neonatal tissues are intensively investigated for their use in regenerative medicine. The purpose of this study was to compare the onset of replicative senescence in MSCs isolated from equine bone marrow (BMSC), adipose tissue (ASC), and umbilical cord tissue (UCMSC). MSC proliferation (cell doubling), senescence-associated β-galactosidase staining, telomere length, Sox-2, and lineage-specific marker expression were assessed for MSCs harvested from tissues of 4 different donors. The results show that before senescence ensued, all cell types prolife...
Schnittger L, Ganzinelli S, Bhoora R, Omondi D, Nijhof AM, Florin-Christensen M.The order Piroplasmida, including the genera Babesia, Cytauxzoon, and Theileria is often referred to as piroplasmids and comprises of dixenous hemoprotozoans transmitted by ticks to a mammalian or avian host. Although piroplasmid infections are usually asymptomatic in wild animals, in domestic animals, they cause serious or life-threatening consequences resulting in fatalities. Piroplasmids are particularly notorious for the enormous economic loss they cause worldwide in livestock production, the restrictions they pose on horse trade, and the negative health impact they have on dogs and cats. ...
Harr KE, Flatland B, Nabity M, Freeman KP.As all laboratory equipment ages and contains components that may degrade with time, initial and periodically scheduled performance assessment is required to verify accurate and precise results over the life of the instrument. As veterinary patients may present to general practitioners and then to referral hospitals (both of which may each perform in-clinic laboratory analyses using different instruments), and given that general practitioners may send samples to reference laboratories, there is a need for comparability of results across instruments and methods. Allowable total error (TEa ) is ...
Smith AV, Proops L, Grounds K, Wathan J, McComb K.Whether non-human animals can recognize human signals, including emotions, has both scientific and applied importance, and is particularly relevant for domesticated species. This study presents the first evidence of horses' abilities to spontaneously discriminate between positive (happy) and negative (angry) human facial expressions in photographs. Our results showed that the angry faces induced responses indicative of a functional understanding of the stimuli: horses displayed a left-gaze bias (a lateralization generally associated with stimuli perceived as negative) and a quicker increase in...
Schnellmann C, Gerber V, Rossano A, Jaquier V, Panchaud Y, Doherr MG, Thomann A, Straub R, Perreten V.Because of the frequency of multiple antibiotic resistance, Staphylococcus species often represent a challenge in incisional infections of horses undergoing colic surgery. To investigate the evolution of antibiotic resistance patterns before and after preventative peri- and postoperative penicillin treatment, staphylococci were isolated from skin and wound samples at different times during hospitalization. Most staphylococci were normal skin commensals and belonged to the common coagulase-negative group. In some cases they turned out to be opportunistic pathogens present in wound infections. M...
Hill EW, Gu J, Eivers SS, Fonseca RG, McGivney BA, Govindarajan P, Orr N, Katz LM, MacHugh DE.Variants of the MSTN gene encoding myostatin are associated with muscle hypertrophy phenotypes in a range of mammalian species, most notably cattle, dogs, mice, and humans. Using a sample of registered Thoroughbred horses (n = 148), we have identified a novel MSTN sequence polymorphism that is strongly associated (g.66493737C>T, P = 4.85x10(-8)) with best race distance among elite racehorses (n = 79). This observation was independently validated (P = 1.91x10(-6)) in a resampled group of Thoroughbreds (n = 62) and in a cohort of Thoroughbreds (n = 37, P = 0.0047) produced by the same trainer...
Weese JS, Holcombe SJ, Embertson RM, Kurtz KA, Roessner HA, Jalali M, Wismer SE.Disruptions in the gastrointestinal microbiota may trigger development of post partum colic. Objective: To determine the effects of the periparturient period on the faecal microbiome and identify associations between the faecal microbiota and post partum colic. Methods: Longitudinal case-control study. Methods: Pre- and post partum faecal samples were collected from mares on 3 farms in central Kentucky. Next generation sequencing of the V4 region of the 16S rRNA gene was performed on samples from 13 mares that developed colic, 13 mares that did not display colic and 5 nonpregnant controls. Res...
Chandriani S, Skewes-Cox P, Zhong W, Ganem DE, Divers TJ, Van Blaricum AJ, Tennant BC, Kistler AL.Theiler's disease is an acute hepatitis in horses that is associated with the administration of equine blood products; its etiologic agent has remained unknown for nearly a century. Here, we used massively parallel sequencing to explore samples from a recent Theiler's disease outbreak. Metatranscriptomic analysis of the short sequence reads identified a 10.5-kb sequence from a previously undescribed virus of the Flaviviridae family, which we designate "Theiler's disease-associated virus" (TDAV). Phylogenetic analysis clusters TDAV with GB viruses of the recently proposed Pegivirus genus, altho...
Bellone RR, Brooks SA, Sandmeyer L, Murphy BA, Forsyth G, Archer S, Bailey E, Grahn B.The appaloosa coat spotting pattern in horses is caused by a single incomplete dominant gene (LP). Homozygosity for LP (LP/LP) is directly associated with congenital stationary night blindness (CSNB) in Appaloosa horses. LP maps to a 6-cM region on ECA1. We investigated the relative expression of two functional candidate genes located in this LP candidate region (TRPM1 and OCA2), as well as three other linked loci (TJP1, MTMR10, and OTUD7A) by quantitative real-time RT-PCR. No large differences were found for expression levels of TJP1, MTMR10, OTUD7A, and OCA2. However, TRPM1 (Transient Recept...
Schnabel LV, Pezzanite LM, Antczak DF, Felippe MJ, Fortier LA.The horse is a valuable species to assess the effect of allogeneic mesenchymal stromal cells (MSCs) in regenerative treatments. No studies to date have examined recipient response to major histocompatibility complex (MHC)-mismatched equine MSCs. The purposes of this study were to immunophenotype MSCs from horses of known MHC haplotype and to compare the immunogenicity of MSCs with differing MHC class II expression. Methods: MSCs and peripheral blood leukocytes (PBLs) were obtained from Thoroughbred horses (n=10) of known MHC haplotype (ELA-A2, -A3, and -A9 homozygotes). MSCs were cultured thro...
Angele P, Abke J, Kujat R, Faltermeier H, Schumann D, Nerlich M, Kinner B, Englert C, Ruszczak Z, Mehrl R, Mueller R.Collagen-based scaffolds are appealing products for the repair of cartilage defects using tissue engineering strategies. The present study investigated the species-related differences of collagen scaffolds with and without 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC)/N-hydroxysuccinimide (NHS)-crosslinking. Resistance against collagenase digestion, swelling ratio, amino acid sequence, shrinkage temperature, ultrastructural matrix morphology, crosslinking density and stress-strain characteristics were determined to evaluate the physico-chemical properties of equine- and bovine-collagen...
Montelaro RC, Parekh B, Orrego A, Issel CJ.The recurrent nature of equine infectious anemia has been attributed to relatively rapid antigenic variations in equine infectious anemia virus (EIAV) during persistent infection under selective immune pressures. This model was tested by serological and biochemical analysis of virus isolates recovered from separate febrile episodes in two experimentally infected ponies. Neutralization assays employing immune sera from the experimentally infected ponies demonstrated that distinct antigenic strains of virus predominate during sequential febrile episodes in a single pony. Analysis of the test str...
Mehlhorn H, Schein E.The horse-parasitizing species Babesia equi Laveran, 1901 was redescribed as Theileria equi Mehlhorn, Schein 1998 and, thus, transferred from one valid genus to another. This transfer was needed since it turned out that this horse parasite showed the relevant characteristics of theilerians with regard to biological data, morphological features, biochemical properties, and molecular biological relationships.
Azlaf R, Dakkak A.The objectives of this epidemiological study on cystic echinococcosis (CE) in Morocco (2001-2004) were to update the prevalence of CE in different animal species living in the most important areas of the country and to collect protoscoleces and germinal layers for genetic research purposes. The post mortem inspection concerned 2948 sheep, 2337 goats, 618 cattle, 482 camels and 455 equines (325 horses, 60 mules and 70 donkeys) in five different regions: the Rif (Mediterranean coast and high mountains of the Rif), the Loukkos (Atlantic northwest plain), the center (Rabat and Casablanca regions),...
