"Horses" is a broad topic that encompasses various aspects of equine biology, behavior, and management. This category includes studies on the anatomy, physiology, and genetics of horses, as well as their behavior, nutrition, and care. Research in this area may also cover the historical and cultural significance of horses, their roles in agriculture, sport, and therapy, and the challenges associated with their conservation and welfare. The page aggregates peer-reviewed research articles and scholarly studies that explore the multifaceted relationships between humans and horses, examining both scientific and socio-economic perspectives.
Page AE, McPeek JL, Carattini S, McGreevy E, Adam E.The goal of this project was to examine the metabolic effects of IA methylprednisolone acetate (MPA) following injection into multiple low-motion joints. Unassigned: Six 3-year-old geldings without pituitary pars intermedia dysfunction or insulin dysregulation were randomly injected with 20 mg of IA MPA/joint (80 mg total; bilateral distal hock joints) or an equal volume of saline. Serial blood samples were collected for resting ACTH, cortisol, insulin, and glucose, as well as insulin and glucose following repeated low-dose oral sugar tests. Treatments were crossed over after a 6-week washout,...
Environmental contamination with heavy metals, resulting from industrialization, urbanization, and agricultural intensification, poses serious ecological and health risks. Horses, due to their grazing behavior and close association with human environments, serve as reliable sentinel species for assessing environmental pollution. This study aimed to evaluate the bioaccumulation of heavy metals and trace elements in different biological matrices of horses-blood, hair, hooves, and synovial fluid-and to investigate their relationship with hematological biomarkers as indicators of physiological str...
Barua S, Tarannum A, Huber L, Easterwood LA, Velayudhan B, Da Silveira BP, Enyetornye B, Cohen ND, Dimitrov KM, Schwarz ER, Awtrey A, Groover E....Over the past decade, newly identified equine hepatotropic flavi- and parvoviruses, such as equine parvovirus-hepatitis (EqPV-H) and equine hepacivirus (EqHV), have generated considerable scientific and clinical interest. Pegiviruses, including Pegivirus (P.) caballi and P. equi, are also recognized and known to frequently cause persistent infections. However, comprehensive epidemiological data in the United States remain limited. This study analyzed 1195 equine serum samples collected from university-owned horses and diagnostic submissions across Alabama, Georgia, and Texas. Quantitative PCR ...
Pereira GF, Blimbliem MCH, Machado ALPR, Abdala JBR, Nogueira GM, Toma HS, de Carvalho TF, Delfiol DJZ.Arsenic poisoning in horses is rarely reported in the literature. However, arsenic compounds can be present in rodenticides, pesticides, and herbicides, representing a potential source of accidental exposure for horses. Objective: To describe the epidemiological, clinical, and laboratory findings from a herd of 31 horses exposed to pasture treated with an overdose of sodium hydrogen methylarsonate, and to compare results in a group of horses exposed to the recommended dosage of the same product. Methods: Observational field study. Methods: Thirty-one horses were evaluated after grazing on a pa...
da Silva Rocha MB, Avelar BR, Martins Dos Santos GC, Ferreira TP, de Sousa Vieira T, de Oliveira GF, Gomes BT, Klafke GM, Correia TR, Cid YP, Scott FB.The objective of this study was to standardize a stall-trial methodology for horses in order to evaluate the pharmacokinetics and efficacy of a 1 % fipronil pour-on formulation against Dermacentor nitens. Brazilian pony breed horses were housed in individual stalls within a covered barn and artificially infested with D. nitens larvae on alternate days from day -31 to -1 before treatment. The animals were treated on day 0 with a fipronil 1 % pour-on at a dose of 1 mg/Kg body weight. To determine the therapeutic efficacy, the number of engorged females naturally detached from control and t...
Jandová V, Huber N, AlMheiri FG, Bábor K, Trachsel DS.Stress represents a serious health and welfare concern; however, its objective assessment remains difficult. The equine gastric ulcer syndrome (EGUS) and orthopedic diseases that cause pain are among stress associated diseases in equine medicine. The leukocyte coping capacity (LCC) quantifies oxygen radical generation of neutrophil granulocytes which is altered under stress. Therefore, LCC could be a novel biomarker for stress in horses and we hypothesized that horses with stress associated diseases would have lower LCC values in comparison to horses without these diseases. Methods: In this ob...
Curry O, Everett A, Pearson G, Dwyer C, Duncan J.Despite the availability of several equine pain assessment tools, their use in equine veterinary practice appears limited compared to small animal practice. This study explores potential barriers to equine pain assessment, as reported by staff at a single UK equine teaching hospital. Methods: Nine hospital staff members were interviewed using semi-structured interviews. Key themes were identified through reflexive thematic analysis. Results: Participants acknowledged the importance of pain assessment, yet highlighted limitations in current methods and their inconsistent use. Key challenges inc...
Willems T, Dias ABM, Dedecker L, Matamalas SS, De Lange L, de Beauregard T.Nephrosplenic space entrapment (NSE) has reported recurrence rates of 8%‒23%, and closure of the nephrosplenic space (NSS) has been shown to lower the incidence. Described techniques for nephrosplenic space closure (NSC) with concurrent left dorsal displacement (LDD) of the colon at the time of surgery consist of reducing the displaced colon prior to closure. Methods: A retrospective study was performed to evaluate the medical records of horse undergoing NSC between 2017 and 2024. A total of 18 horses with LDD at time of NSC and 21 without displacement at time of NSC were evaluated. Short- a...
Rangel A, Sellon DC, Sanz MG, Pinnell E, Pietras ZM, Villarino NF.Pharmacokinetics (PK) of intramuscular (IM) and subcutaneous (SC) ketamine in horses has not been described. This study aimed to evaluate the PK and safety of ketamine and its metabolites after a single SC or IM administration. In Phase 1, two horses received 0.5 or 1 mg/kg of ketamine via SC and IM routes. In Phase 2, eight horses received 0.5 mg/kg IM. Plasma or serum concentrations of ketamine and major metabolites were determined by a validated liquid chromatography-mass spectrometry method at baseline and selected intervals post-administration. Subcutaneous administration resulted in ...
Stäubli T, Theiss F, Bischofberger A.A total of 48 horses with unilateral (n = 44) or bilateral (n = 4) overstrain-induced complete rupture of the superficial digital flexor tendon (SDFT) in the forelimbs were retrospectively analysed. A telephone questionnaire, carried out an average of 5,9 years post-injury, served as a long-term follow-up in 25 horses. The mortality rate associated with SDF tendonitis was 12,0 % (3/25). Superficial digital flexor tendonitis did not recur in 76,0 % (19/25) of the horses, but at least one subsequent episode occurred in 24,0 % (6/25). The results of this study indicate that it is reasonable...
Kwak ML, Echigo H, Hoketsu T, Taya Y, Numata H, Shiraki Y, Kelava S, Markowsky G, McInnes D, Hayashi N, Nonaka N, Kawai M, Nakao R.The control of ticks is challenging owing to their ubiquity, complex ecologies, and difficulties relating to costs and non-target impacts of chemical control programs. Nature-based solutions centre around co-opting natural processes and biodiversity to address socio-environmental problems; and in some cases, rewilded species can provide nature-based solutions. In northern Japan, the winter ecology of ticks is poorly studied, though some species are believed to overwinter under the snow. Winter grazing activity of rewilded horses may disturb overwintering ticks, exposing them to sub-zero temper...
Haugaard SL, Schneider MJ, Kjeldsen ST, Sattler SM, Bastrup JA, Saljic A, Birk JB, Hansen C, Synnestvedt JN, van Hunnik A, Sobota V, Carstensen H....Horses are one of the few animals that spontaneously develop atrial fibrillation (AF), making them a powerful model for studying AF mechanisms and treatment effects. Despite the initial effectiveness of treatment in horses and humans, AF-induced atrial remodeling compromises its long-term success. Observational studies have suggested that metformin may reduce the risk of AF, but its effects on progressive AF-induced atrial remodeling have yet to be evaluated in a high-fidelity large animal model. Unassigned: Here, we used a longitudinal horse model of tachypacing-induced self-sustained AF to c...
Lee S, Hector RC, Hess AM, Wotman KL.To determine whether dexmedetomidine prolongs corneal anesthesia following subconjunctival ropivacaine injection in healthy equine eyes. Methods: Ten horses with normal ophthalmic exams were enrolled in a randomized, blinded, crossover experiment with a minimum 4-week washout between treatments. Baseline corneal touch thresholds (CTT, cm) were measured via esthesiometry and a subconjunctival injection was performed in the treatment eye with ropivacaine (R, 0.3 mL 0.5%) or dexmedetomidine-ropivacaine (DR, 0.1 mL 0.5 mg/mL + 0.2 mL 0.5%) and saline (control, 0.3 mL) in the contrala...
Bolesławska-Szubartowska J, Kucharczuk M, Skrabska A, Zbysław A, Adamowicz J, Alszko A, Domagalska-Stomska K, Durska M, Dziekcierów A....Pain after giving birth is commonly observed in horses, yet there has not been a specific tool developed for assessing this pain in postpartum mares. The goal was to adapt existing equine pain scales and to preliminarily validate a practical pain scale for use by veterinarians and caregivers after foaling. Methods: The pain scale was developed by adapting items from other pain scales, including established orthopedic and colic equine pain scales, and incorporating caregiver feedback. The final scale includes eight areas for assessing pain: behavior, facial expressions, vital signs, udder exami...
Chessari G, Reich P, Criscione A, Falker-Gieske C, Mastrangelo S, Tumino S, Bordonaro S, Marletta D, Tetens J.Single nucleotide polymorphism (SNP) arrays are commonly used for studying the genomic structure and diversity of livestock breeds, but whole-genome sequencing (WGS) provides higher-resolution genomic data. Genotype imputation has become a standard practice for increasing the genomic resolution of association studies. This work aimed to extend imputation to biodiversity analyses, comparing SNP array data before and after imputation. A 40 k SNP dataset of 281 horses from 12 breeds (DS) was imputed to sequence-level using a reference panel of 327 sequenced individuals, generating approximately 9...
Song D, Wang G, Baterin T, Weng Y, Dugarjaviin M, Li B.Normal spermatogenesis in Mongolian horses depends on the mitotic division of spermatogonia, two successive meiotic divisions, and the morphological transformation of spermatids into mature spermatozoa. The gene is involved in the meiosis cycle and is required for normal chromosome association during meiosis. Previous studies have shown that alternative splicing of may promote spermatogenesis in Mongolian horses. In this paper, the regulatory effects of different alternative splicing events on Mongolian horse spermatogenesis are investigated. Results: In this study, two overexpressed lentiv...
Stoeckle SD, Stage HJ, Gehlen H.Thyroid diseases in horses are rare and pose challenges for veterinarians due to the complexity of clinical and diagnostic approaches. This retrospective case series describes cases of equine thyroid disease in a referral hospital population. Files of horses examined for suspected thyroid disease at an equine university clinic between 2009 and 2024 were reviewed. Data from nine horses examined for suspected thyroid disease, including signalment, clinical presentation, laboratory results, imaging findings, fine needle aspirates, biopsies, diagnoses, and treatments, were summarised. Diagnoses in...
Costa VMD, de Aguiar Filho RN, Braz GF, Paz CFR, Drumond BP, Teixeira BM, Kroon EG.Equine infectious anemia (EIA) is a chronic disease caused by the equine infectious anemia virus (EIAV), a member of the Retroviridae family and the Lentivirus genus. Most infected animals are asymptomatic carriers, which makes clinical diagnosis challenging. This study aimed to conduct a clinical and laboratory evaluation of EIA in equids used for equestrian tourism in Jericoacoara National Park, Ceará, Brazil. A total of 112 equids (104 horses and 8 mules) underwent clinical, hematological, biochemical, serological, and molecular assessments. The EIAV seropositivity rates were 11.6% by AGID...
Björnsdóttir S, Sigurðardóttir ÓG, Oddsdóttir C, Reynisdóttir I, Hanche-Olsen S, Gröndahl G.Acquired equine polyneuropathy is a neuromuscular syndrome characterized by digital extensor dysfunction, primarily affecting the pelvic limbs, with consistent, repeated knuckling. Despite being recognized as an emerging disease in Scandinavia since 1995, the aetiology remains unknown, and cases have been limited to Norway, Sweden, and Finland. Methods: On a combined breeding and training farm in Iceland, 30 out of 145 horses (21%) presented with acute pelvic weakness, pelvic limb digital extensor dysfunction, knuckling and/or recumbency, from May to August 2019. The affected horses, aged 2-9...
Clark KF, Lemcke RA, Gasiorowski JC, Wagner B.Lyme arthritis, a well-documented subtype of arthritis in humans and dogs, is caused by Borrelia burgdorferi and spread primarily through ticks (Ixodes spp.). While Lyme disease in horses is known to cause a variety of clinical signs, its involvement in the development of equine arthritis is controversial. As climate change enables tick populations to expand, more horses could be exposed to B. burgdorferi; therefore, a greater understanding of how Lyme disease affects joints is critical to preserving soundness. Objective: To determine if systemic, naturally occurring Lyme disease had a discern...
Sullivan J, Blea J, Morales CJ, McKemie DS, Kass PH, Knych HK.Corticosteroids, such as isoflupredone, are effective anti-inflammatory medications and as such are commonly used to treat inflammation associated with training and injuries in performance horses. While the pharmacokinetics and pharmacodynamics of isoflupredone acetate (IPA) following intra-articular administration to horses has been well described, studies characterizing intramuscular (IM) administration are lacking. The objective of the current study was to describe the pharmacokinetics and anti-inflammatory effects of IPA following IM administration to horses. Twelve horses received a singl...
Moghbeli Damane M, Ayatollahi Mehrgardi A, Esmailizadeh A, Momen M.Inbreeding is caused by mating between related individuals and is associated with reduced fitness and performance. Generally, in the horse population, inbreeding is caused by geographically restricted areas and intensive natural or artificial selection. For this reason, assessing accurate inbreeding is essential for developing and implementing effective breeding strategies aimed at preserving genetic diversity and reducing the harmful consequences of inbreeding. One of the most accurate approaches for assessing genomic inbreeding and autozygosity is through the analysis of runs of homozygosity...
Gröndahl G, Righetti F, Aspán A, Bjerketorp J, Frosth S, Frykberg L, Jacobsson K, Guss B, Paillot R, Flock JI, Henriques-Normark B, Waller AS.Strangles, caused by Streptococcus equi subspecies equi (S. equi), is a prevalent infectious disease of horses. This is the first report on the use of a new vaccine, Strangvac, in a natural outbreak of strangles. Objective: To measure the effects of Strangvac vaccination during an outbreak of strangles at a Swedish farm. Methods: Longitudinal cohort study. Methods: Healthy horses (n = 17) were vaccinated on day 0, which occurred 23 days after strangles was first confirmed in three unvaccinated horses on the same farm. Blood serum samples were collected on day 0, day 28 and day 489. A com...
Stachurska A, Wnuk E, Łuszczyński J, Donderowicz W.Correct conformation and symmetry of bilateral hooves are associated with a properly balanced hoof, which has a significant impact on the biomechanics of movement and reduces the risk of injury. The aim of the study was to compare solear aspect dimensions of bilateral hooves in forelimbs (hoof width, length, frog width, length, medial and lateral diagonals) with regard to sex, breed and age of horses. The dimensions were measured with a calliper in 100 horses of four breeds. The results showed that the breed factor significantly affected all dimensions. Age was significant for some variables, ...
Rossi GAM, Sellera FP, Ferraz CM, Carvalho RS, Oliveira APL, Marques CA, Fávaro EBR, Rosa RDS, Silva LAM, Cardozo MV, Stehling EG, Furlan JPR. Infections caused by antimicrobial-resistant bacteria are difficult to treat and increase the risk of death in animals. This report describes a fatal case of diarrhea in a horse that, despite intensive treatment including surgery and broad-spectrum antimicrobials (ceftiofur and amikacin), experienced a worsening of its condition and subsequent death. A fecal swab sample was subjected to microbiological culture for the identification of bacteria and assessment of their phenotypical antimicrobial susceptibility profiles using the disk-diffusion and broth microdilution methods. The double-disk ...
Pennington MV, Zoller JL, White-Springer SH, Harlin JF, Huseman CJ, Leatherwood JL, O'Reilly CL.Competition stress is a common factor influencing the success of performing athletes. However, few studies have quantified the physiological stress responses in horses and riders surrounding an equestrian event. Objective: The objectives of the current study were to determine salivary cortisol concentrations (SCC) as an indicator of stress in fifteen horse and rider pairs competing in western stock horse events and to investigate the relationship between SCC and performance. Methods: Subjects included male and female Quarter horses aged 3-15 years and equestrians aged 18-22 years. Salivary sam...
Keller P, Vanwesenbeeck I, Hudders L, Decloedt A.To assess horse owners' behaviors and perceptions regarding communication about complementary and alternative veterinary medicine (CAVM) with their veterinarian. Unassigned: A cross-sectional online survey was combined with a qualitative study in the form of in-depth interviews with Flemish horse owners. Unassigned: The study included 1,532 fully completed survey responses and 26 interviews. Overall, horse owners showed high trust in the veterinarian and were satisfied with veterinarian-client communication. While 61.7% of participants indicated that they had already talked about CAVM with the...
McCrae P, Spong H, Moorehead J, Pearson W.A smart textile device has been developed for the recording of electrocardiograms (ECGs) in horses; however, the utility of this device for long-duration heart rate variability (HRV) monitoring and detection of physiological arrhythmias is unknown. Therefore, the objective of this study was to validate a smart textile device for HRV over long durations (6 h) in resting horses. ECGs were recorded simultaneously via the Myant Skiin Equine textile device and a reference device (Televet 100) in 12 horses. ECGs were evaluated by a blinded observer for arrhythmias, and HRV metrics were calculated. ...
Wang T, Li M, Ren W, Meng J, Yao X, Chu H, Yao R, Zhai M, Zeng Y.Yili horses undergo coordinated physiological adaptations across systems in response to customized training. This study aimed to clarify the molecular mechanisms of these adaptations by integrating analyses of cardiac function and multi-omics (lipidomics, transcriptomics, miRNomics). We collected whole blood samples from ten Yili horses before and after 12 weeks of specialized racing training to perform these analyses. Results showed training induced adaptive cardiac remodeling, with substantial increases in LVIDd and LVIDs. At the molecular level, this was accompanied by extensive blood lipid...
Zuluaga-Cabrera AM, Barbosa da Costa G, Martinez ID, Arias MP.Colombian Paso horses (CPs) excel in gait competitions due to their endurance, speed, and precision, which demand a high level of cardiorespiratory fitness. However, their training regimes often lack scientific support, and few studies have linked physiological parameters to optimal training zones. This study aimed to estimate the aerobic lactate threshold (LTaer) using mathematical methods and to correlate it with heart rate (HR) zones and blood lactate. Eighteen CPs were evaluated and classified into trained (GT) and untrained (GD) groups. All animals underwent a field-based incremental exer...
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 ...
Scoles GA, Ueti MW.Equine piroplasmosis is a disease of Equidae, including horses, donkeys, mules, and zebras, caused by either of two protozoan parasites, Theileria equi or Babesia caballi. These parasites are biologically transmitted between hosts via tick vectors, and although they have inherent differences they are categorized together because they cause similar pathology and have similar morphologies, life cycles, and vector relationships. To complete their life cycle, these parasites must undergo a complex series of developmental events, including sexual-stage development in their tick vectors. Consequentl...
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...
The intestinal tract is a rich and complex environment and its microbiota has been shown to have an important role in health and disease in the host. Several factors can cause disruption of the normal intestinal microbiota, including antimicrobial therapy, which is an important cause of diarrhea in horses. This study aimed to characterize changes in the fecal bacterial populations of healthy horses associated with the administration of frequently used antimicrobial drugs. Results: Twenty-four adult mares were assigned to receive procaine penicillin intramuscularly (IM), ceftiofur sodium IM, tr...
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...
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...
Shepherd ML, Swecker WS, Jensen RV, Ponder MA.The diversity of the equine fecal bacterial community was evaluated using pyrosequencing of 16S rRNA gene amplicons. Fecal samples were obtained from horses fed cool-season grass hay. Fecal bacteria were characterized by amplifying the V4 region of bacterial 16S rRNA gene. Of 5898 mean unique sequences, a mean of 1510 operational taxonomic units were identified in the four fecal samples. Equine fecal bacterial richness was higher than that reported in humans, but lower than that reported in either cattle feces or soil. Bacterial classified sequences were assigned to 16 phyla, of which 10 were ...
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...
Bullone M, Lavoie JP.Animal models have been studied to unravel etiological, immunopathological, and genetic attributes leading to asthma. However, while experiments in which the disease is artificially induced have helped discovering biological and molecular pathways leading to allergic airway inflammation, their contribution to the understanding of the causality of the disease has been more limited. Horses naturally suffer from an asthma-like condition called "heaves" which presents sticking similarities with human asthma. It is characterized by reversible airway obstruction, airway neutrophilic inflammation, an...
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),...
Metcalf JL, Song SJ, Morton JT, Weiss S, Seguin-Orlando A, Joly F, Feh C, Taberlet P, Coissac E, Amir A, Willerslev E, Knight R, McKenzie V, Orlando L.The mammal gut microbiome, which includes host microbes and their respective genes, is now recognized as an essential second genome that provides critical functions to the host. In humans, studies have revealed that lifestyle strongly influences the composition and diversity of the gastrointestinal microbiome. We hypothesized that these trends in humans may be paralleled in mammals subjected to anthropogenic forces such as domestication and captivity, in which diets and natural life histories are often greatly modified. We investigated fecal microbiomes of Przewalski's horse (PH; Equus ferus p...
Garber A, Hastie P, Murray JA.Gastrointestinal microbiota play a crucial role in nutrient digestion, maintaining animal health and welfare. Various factors may affect microbial balance often leading to disturbances that may result in debilitating conditions such as colic and laminitis. The invention of next-generation sequencing technologies and bioinformatics has provided valuable information on the effects of factors influencing equine gut microbiota. Among those factors are nutrition and management (e.g., diet, supplements, exercise), medical substances (e.g., antimicrobials, anthelmintics, anesthetics), animal-related ...
Dougal K, de la Fuente G, Harris PA, Girdwood SE, Pinloche E, Geor RJ, Nielsen BD, Schott HC, Elzinga S, Newbold CJ.Faecal samples were collected from seventeen animals, each fed three different diets (high fibre, high fibre with a starch rich supplement and high fibre with an oil rich supplement). DNA was extracted and the V1-V2 regions of 16SrDNA were 454-pyrosequenced to investigate the faecal microbiome of the horse. The effect of age was also considered by comparing mature (8 horses aged 5-12) versus elderly horses (9 horses aged 19-28). A reduction in diversity was found in the elderly horse group. Significant differences between diets were found at an OTU level (52 OTUs at corrected Q<0.1). The ma...
Daly K, Proudman CJ, Duncan SH, Flint HJ, Dyer J, Shirazi-Beechey SP.We aimed to determine the effects of variations in dietary composition on equine gut microbiota and their fermentation products, and proposed that dietary modifications profoundly affect microbial ecosystems and their metabolites. Bacterial communities within the large intestine of three groups of horses were compared using oligonucleotide-RNA hybridisation methodology. Each group consisting of six horses was maintained on (1) a grass-only diet, (2) a concentrate diet (i.e. supplemented with hydrolysable carbohydrates) and (3) a concentrate diet but horses were affected by simple colonic obstr...
Keegan KG, Kramer J, Yonezawa Y, Maki H, Pai PF, Dent EV, Kellerman TE, Wilson DA, Reed SK.To determine repeatability of a wireless, inertial sensor-based lameness evaluation system in horses. Methods: 236 horses. Methods: Horses were from 2 to 29 years of age and of various breeds and lameness disposition. All horses were instrumented with a wireless, inertial sensor-based motion analysis system on the head (accelerometer), pelvis (midline croup region [accelerometer]), and right forelimb (gyroscope) before evaluation in 2 consecutive trials, approximately 5 minutes apart, as the horse was trotted in a straight line. Signal-processing algorithms generated overall trial asymmetry me...
Nixon AJ, Dahlgren LA, Haupt JL, Yeager AE, Ward DL.To assess the potential of adipose-derived nucleated cell (ADNC) fractions to improve tendon repair in horses with collagenase-induced tendinitis. Methods: 8 horses. Methods: Collagenase was used to induce tendinitis in the superficial digital flexor tendon of 1 forelimb in each horse. Four horses were treated by injection of autogenous ADNC fractions, and 4 control horses were injected with PBS solution. Healing was compared by weekly ultrasonographic evaluation. Horses were euthanatized at 6 weeks. Gross and histologic evaluation of tendon structure, fiber alignment, and collagen typing were...
Frisbie DD, Al-Sobayil F, Billinghurst RC, Kawcak CE, McIlwraith CW.To discriminate between changes in biomarkers with exercise compared to changes in biomarkers with osteoarthritis (OA) in exercising horses. Methods: Sixteen, 2-year-old horses were randomly assigned either to an exercise-alone (n=8) or OA-affected (also exercised) (n=8) group. All horses had both mid-carpal joints arthroscoped and OA induced in one mid-carpal joint in the OA-affected joints of OA-affected horses. Two weeks after surgery all horses commenced a strenuous exercise program on a high-speed treadmill. Clinical outcomes and synovial fluid and serum biomarkers, were evaluated weekly....
Hauswirth R, Haase B, Blatter M, Brooks SA, Burger D, Drögemüller C, Gerber V, Henke D, Janda J, Jude R, Magdesian KG, Matthews JM, Poncet PA....During fetal development neural-crest-derived melanoblasts migrate across the entire body surface and differentiate into melanocytes, the pigment-producing cells. Alterations in this precisely regulated process can lead to white spotting patterns. White spotting patterns in horses are a complex trait with a large phenotypic variance ranging from minimal white markings up to completely white horses. The "splashed white" pattern is primarily characterized by an extremely large blaze, often accompanied by extended white markings at the distal limbs and blue eyes. Some, but not all, splashed white...
Keegan KG, Dent EV, Wilson DA, Janicek J, Kramer J, Lacarrubba A, Walsh DM, Cassells MW, Esther TM, Schiltz P, Frees KE, Wilhite CL, Clark JM....Previous studies have suggested that agreement between equine veterinarians subjectively evaluating lameness in horses is low. These studies were limited to small numbers of horses, evaluating movement on the treadmill or to evaluating previously-recorded videotape. Objective: To estimate agreement between equine practitioners performing lameness evaluations in horses in the live, over ground setting. Methods: 131 mature horses were evaluated for lameness by 2-5 clinicians (mean 3.2) with a weighted-average of 18.7 years of experience. Clinicians graded each limb using the AAEP lameness scale ...
Schneider J, Kaaden O, Copeland TD, Oroszlan S, Hunsmann G.Two glycopolypeptides with molecular weights 160,000 and 120,000 (gp120) are regularly recognized by human immunodeficiency virus (HIV)-specific antisera in lysates of cells persistently infected with HIV. In the present study, gp120 was characterized as the major envelope glycopolypeptide of HIV. Gp120 was identified as the external viral glycoprotein by radiosequencing and by its presence in purified virus. However gp120 was predominantly shed as a soluble protein into the culture fluid. Furthermore gp120 was precipitated by sera from horses infected with equine infectious anaemia virus (EIA...
Rivas F, Diaz LA, Cardenas VM, Daza E, Bruzon L, Alcala A, De la Hoz O, Caceres FM, Aristizabal G, Martinez JW, Revelo D, De la Hoz F, Boshell J....In 1995, the first Venezuelan equine encephalitis (VEE) outbreak in Colombia in 22 years caused an estimated 75,000 human cases, 3000 with neurologic complications and 300 fatal, in La Guajira State. Of the state's estimated 50,000 equines, 8% may have died. An epizootic IC virus, probably introduced from Venezuela, was rapidly amplified among unvaccinated equines. Record high rainfall, producing high densities of vector Aedes taeniorhynchus, led to extensive epidemic transmission (30% attack rate) in the four affected municipalities. Native Wayuu Indians, constituting 24% of the state's popul...
Cooper KL, Sears KE, Uygur A, Maier J, Baczkowski KS, Brosnahan M, Antczak D, Skidmore JA, Tabin CJ.A reduction in the number of digits has evolved many times in tetrapods, particularly in cursorial mammals that travel over deserts and plains, yet the underlying developmental mechanisms have remained elusive. Here we show that digit loss can occur both during early limb patterning and at later post-patterning stages of chondrogenesis. In the 'odd-toed' jerboa (Dipus sagitta) and horse and the 'even-toed' camel, extensive cell death sculpts the tissue around the remaining toes. In contrast, digit loss in the pig is orchestrated by earlier limb patterning mechanisms including downregulation of...
Bosch G, van Schie HT, de Groot MW, Cadby JA, van de Lest CH, Barneveld A, van Weeren PR.Tendon injuries are notorious for their slow and functionally inferior healing. Intratendinous application of platelet-rich plasma (PRP) has been reported to stimulate the repair process of tendon injuries, but there is little conclusive evidence for its effectiveness. A placebo-controlled experimental trial was performed to test the hypothesis that a single intratendinous PRP treatment enhances the quality of tendon repair, as evidenced by improved biochemical, biomechanical, and histological tissue properties. In six horses, tendon lesions were created surgically in the Superficial Digital F...
Yánez-Ortiz I, Catalán J, Rodríguez-Gil JE, Miró J, Yeste M.Sperm cryopreservation is one of the most important procedures in the development of biotechnologies for assisted reproduction. In some farm animals, the use of cryopreserved sperm has so many benefits for which relevance has become more evident in recent decades. Values for post-thaw sperm quality, however, are variable among species and within individuals of the same species. There is no standardized methodology for each of the stages of the cryopreservation procedure (andrological examination, semen collection, dilution, centrifugation, resuspension of the pellet with the freezing medium, p...
Hillier ML, Bell LS.This review brings together a complex and extensive literature to address the question of whether it is possible to distinguish human from nonhuman bone using the histological appearance of cortical bone. The mammalian species included are rat, hare, badger, racoon dog, cat, dog, pig, cow, goat, sheep, deer, horse, water buffalo, bear, nonhuman primates, and human and are therefore not exhaustive, but cover those mammals that may contribute to a North American or Eurasian forensic assemblage. The review has demonstrated that differentiation of human from certain nonhuman species is possible, i...
Fureix C, Jego P, Henry S, Lansade L, Hausberger M.Recent reviews question current animal models of depression and emphasise the need for ethological models of mood disorders based on animals living under natural conditions. Domestic horses encounter chronic stress, including potential stress at work, which can induce behavioural disorders (e.g. "apathy"). Our pioneering study evaluated the potential of domestic horses in their usual environment to become an ethological model of depression by testing this models' face validity (i.e. behavioural similarity with descriptions of human depressive states). Results: We observed the spontaneous behav...
