Equine health encompasses the study and management of diseases, disorders, and overall well-being of horses. It involves understanding various physiological systems, preventive care, and treatment strategies to maintain optimal health in equine populations. Common areas of focus include nutrition, infectious diseases, orthopedic conditions, and reproductive health. Research in equine health aims to advance knowledge on diagnostic methods, therapeutic interventions, and management practices that improve horse welfare and performance. This page collects peer-reviewed research studies and scholarly articles that explore the diverse aspects of equine health, offering insights into current findings and advancements in the field.
Nixon W, Buckley P, Butler R.There is a lack of information on horse parasite management practices currently used by individual horse owners in Australia. A voluntary, anonymous online survey was developed for and distributed by Pony Club Australia to its members seeking information on horse population; housing; paddock, manure and parasite management; and owner attitudes. From a total of 98 completed responses, 95/98 of participants indicated their horses spent time in paddocks, 91/98 administered anthelmintics, 42/98 guessed their horse's body weight for dosing, 78/98 recalled the dewormer brand or active ingredient las...
Aliani C, Lorenzetto Bologna C, Francia P, Bocchi L.Standing equine computed tomography (CT) acquisitions are susceptible to residual postural sway, which can introduce view-inconsistent motion and degrade image quality. External optical tracking based on ChArUco fiducials is a promising, low-cost strategy to enable projection-wise motion compensation, yet quantitative guidance on how camera-marker geometry affects pose-estimation performance remains limited. This CT-motivated benchtop study characterizes how the relative camera-ChArUco configuration influences both the accuracy (bias with respect to ground truth) and the precision (repeatabili...
Mukai K, Takahashi Y, Ebisuda Y, Sugiyama F, Yoshida T, Miyata H.This study tested the hypothesis that 6 weeks of high-intensity interval training (HIIT) would induce greater physiological adaptations than moderate-intensity continuous training (MICT) in Thoroughbred horses. Seven untrained horses completed two distance-matched treadmill training protocols (three sessions per week) in a randomized crossover design, separated by a three-month washout: MICT (6 min at 70% ) and HIIT (6 × [30 s at 100% with 30 s at 30% ]). Incremental exercise tests were conducted at weeks 0, 3, and 6 to assess exercise performance and physiological responses. M...
Aimonetti E, Genton M, Lischer CJ, Rossignol F.To determine the benefit of using a three-dimensional (3D)-printed titanium aiming device for placing two 5.5-mm transarticular screws during proximal interphalangeal joint (PIPJ) arthrodesis in equine species. Methods: Ex vivo study. Methods: A total of 40 cadaveric forelimbs from adult horses. Methods: A senior surgeon and a first-year resident each performed 20 constructs: 10 using the device and 10 using a freehand technique. Procedure duration and number of intraoperative radiographs were recorded. Final radiographs were evaluated by an ECVS-certified surgeon unaware of treatment group, b...
Mählmann K, Lischer CJ.This technical note describes the use of a manual graphic roadmap (MGR) to assist fluoroscopic guidance during transarterial coil embolization (TACE) for guttural pouch (GP) arterial hemorrhage. Horses underwent MGR-assisted TACE at the Equine Clinic, Free University of Berlin, between 2012 and 2024. Surgery was performed under general anesthesia with fluoroscopic guidance. Following the initial angiogram, a transparent foil was secured to the fluoroscopy monitor, and an assistant traced the vascular anatomy with a waterproof marker to create the MGR, which then served as a guide for catheter ...
Strugava L, Serighelli-Júnior G, Stadler LM, Flores LADS, Minozzo GA, Dornbusch LPTC, Moreno JCD, Dornbusch PT.Rectal amputation is a surgical approach indicated for the management of severe rectal lacerations or extensive rectal prolapse when transmural compromise or primary repair is unfeasible. These conditions, although uncommon, present substantial challenges in equine practice due to the anatomical complexity of the pelvic region and the potential for life-threatening complications if not adequately addressed. This study aimed to describe and standardize a reproducible surgical technique for rectal amputation in horse cadavers. Six equine cadavers (mean body mass, 441.83± 66.84 kg) were position...
Gallacher K, Woolford L, Gilbert RO, Santos LC, McLeod J, Hebart M, Agne GF, du Preez S, Kind KL.Assessment of the endometrium is an essential component of a breeding soundness examination in mares. The current reference standard for evaluating equine endometrial health is histopathological assessment of an endometrial biopsy, however, inconsistencies may arise when a single blinded biopsy is used. Confocal laser endomicroscopy (CLE) is non-invasive and enables real-time in-vivo imaging of the endometrium across multiple locations within the uterine lumen. An initial study revealed variation in CLE image quality between mares. Objective: This study aimed to compare the quality of endometr...
Luedke LK.This article provides an overview of equine paranasal sinus disease with emphasis on relevant anatomy, diagnostic considerations, and commonly encountered pathologic conditions. It outlines the structure and drainage of the paranasal sinuses to establish a foundation for understanding disease development and spread. The discussion reviews available diagnostic modalities and their roles in localizing disease and determining underlying causes. Common sinus disorders are presented with attention to their general pathophysiology, diagnostic features, treatment approaches, and expected outcomes. Co...
Samuels AN, Collins N, Albrecht M, Cuming R, Reed S, Gomez D, Toribio R.To evaluate associations between the neutrophil-to-lymphocyte ratio (NLR), nonsurvival, illness severity, and infectious etiologies. Unassigned: This was a retrospective multicenter study that included 100 healthy horses and 444 horses presenting with acute diarrhea to 5 equine referral hospitals. Inclusion criteria were diarrhea duration < 48 hours, complete hemograms, and outcome data. Illness severity was assessed using systemic inflammatory response syndrome. The results of pathogen testing for Salmonella spp, equine coronavirus, Clostridium spp, and Neorickettsia risticii/findlayensis ...
Cerullo A, Scilimati N, Di Nicola MR, Colla L, Mazza S, Bertoletti A, Nannarone S, Gialletti R.Left dorsal displacement of the large colon (LDDLC) is a common cause of colic in horses and it is frequently associated with recurrent episodes, with significant implications for horse management, athletic performance, and owner satisfaction. Laparoscopic nephrosplenic space (NSS) ablation is a preventive surgical technique aimed at reducing recurrence in horses with a history of medically or surgically treated LDDLC. This retrospective study evaluated 48 horses that underwent laparoscopic NSS ablation in two Italian Veterinary Teaching Hospitals between 2016 and 2024. Short-term outcomes, in...
Burns JJ, MacMillan KM.The Standardbred racing industry plays an important role in the North American economy and is expected to continue operating and growing. However, public perception is often unfavorable, with increasing concern about the health and welfare of Standardbred racehorses. Despite this, limited research has examined Standardbred well-being. To address this gap, a survey of equine trainers on Prince Edward Island (PEI) was conducted to evaluate key health and welfare issues during racing careers. Results showed that over one quarter of respondents had at least one horse displaying stereotypic behavio...
Häussling MPP, Steinberg T, Büttner K, Hannig C, Hannig M, Lemke L, Zierau O, Staszyk C.Destructive lesions of the peripheral and infundibular cementum are increasingly recognized in equine dentistry. While similarities to human caries have been noted, current evidence does not conclusively support this classification. This study aims to assess the prevalence, distribution, and potential risk factors associated with these lesions in a defined horse population. Unassigned: A total of 114 horses from northern Germany underwent standardized oral examination between 2021 and 2023. Clinical data on peripheral and infundibular lesions, diastemata, and influencing factors such as age an...
Zimmerman-Cameron SR, Colbath AC, Caruso MA, Hoffman RM, Logan AA.Navicular syndrome is characterized by palmar foot pain and is a common cause of lameness in horses. Palmar digital neurectomy (nerving) removes sensation to the heel region of the hoof and may serve as a treatment for navicular-afflicted horses, while analgesia (blocking) results in temporary loss of sensation. Objective: The purpose of this pilot study was to examine the effect of loss of sensation in the heel on the forelimb area and force while tracking on soft and hard ground at the walk and trot. Methods: Three horses that scored a 0 or 1 on the AAEP lameness scale were fitted to Tekscan...
Hallowell KL, van Eps AW, Kulp JC, Schnabel LV.Lipemia is a common comorbidity in horses with obesity or equine metabolic syndrome, but the impact of lipemia on the measurement of insulin and adiponectin has not been evaluated. Objective: To evaluate endogenous and exogenous lipemic interference with equine insulin and adiponectin measurements via several commercial assays. Methods: Endogenous lipemia was evaluated using plasma and serum samples with triglyceride concentrations of 1000 mg/dL (n = 6 each). Sample insulin concentrations were determined via fluorescence enzyme immunoassay (FEIA), ELISA, and lateral flow assay (LFA). ...
Bramall LM, Hinnigan GJ, Wattam AD, Owen KR.This case report describes the successful hemithyroidectomy of the largest equine solid follicular adenoma described in the veterinary literature to date. A 19-year-old thoroughbred mare was referred to Oakhill Veterinary Centre for the surgical removal of a large, left-sided thyroid gland measuring 26cm in diameter. Pre-operative considerations, the hemithyroidectomy surgical technique as well as the intra- and post-operative complications encountered, are discussed. Following surgery the horse had no long-term complications and continues to thrive four and a half years post-operatively.
Markowitz JS.Equibase (EQB) race charts provide the official record of North American Thoroughbred races and often document catastrophic injury, euthanasia, or equine-ambulance transport. Because chart documentation and regulatory classification differ, fatalities occurring > 72 hours after a race fall outside international regulatory definitions applied by the Equine Injury Database (EID) and may not appear in EID aggregates. EQB charts confirm horse identity, race participation, finishing status, and last recorded start. Horseracing Wrongs (HRW), an advocacy group, publishes horse-level fatality data tha...
Bish-Jones AR, Papich MG, Orsini JA.This study describes the pharmacokinetics of ertapenem, a carbapenem antimicrobial that has not been previously studied in equids. Administered as a 30 mg/kg intravenous bolus to six healthy horses, serial blood and synovial samples were obtained over 8 h after administration. Pharmacokinetic analysis of plasma and synovial fluid was performed. In plasma, the AUC was 353.10 h × μg/mL (CV = 49.02%), Vss 79.34 mL/kg (CV = 22.85%), CL 84.96 mL/h/kg (CV = 31.31%) and t1/2 2.03 h (CV = 15.32%). In synovial fluid, the AUC was 524.10 h × μg/mL (CV = 16.03...
Kamr A, Fortin-Trahan R, Arroyo LG, Hostnik LD, Gomez DE, Toribio RE.Hypocalcemia is frequent in horses with colitis. Information on serum parathyroid hormone (PTH) concentrations and its association with bone turnover biomarkers in horses with colitis is lacking. We aimed to determine the association between serum bone resorption biomarkers (C-terminal telopeptide of type I collagen [CTX-I]) and bone formation (osteocalcin [OCN]) with blood PTH, total calcium (tCa), ionized calcium (iCa), phosphorus (Pi), and total magnesium (tMg) concentrations, and mortality in horses with acute colitis. A total of 163 horses were divided into colitis (n = 127) and healt...
Díaz-Alvarado T, Alcala-Canto Y, Elghandour MMMY, Salem MZM, Mariezcurrena-Berasain MD, Salem AZM.Gastrointestinal endoparasitic diseases, particularly those caused by some strongyles, represent one of the main health challenges in equine production. The prolonged use of synthetic anthelmintics has led to the development of resistance, which has prompted the search for more sustainable therapeutic alternatives. However, plant extracts rich in secondary metabolites are emerging as a promising option. Objective: The objective of this study was to evaluate the in vitro anthelmintic activity of aqueous extracts and bioactive compounds (total phenols and saponins) from Azadirachta indica and Cn...
Hall NP, Sweeney DM, Holmströem M, Kim W, Wang Y, Donahue KD, Palmer SE, Lambert DH, Bayly WM.To determine whether targeted lesion-specific algorithms developed from data collected with accelerometer-based inertial measurement units worn by racing Thoroughbreds could retrospectively identify horses at high risk of incurring forelimb condylar or proximal sesamoid fractures. Unassigned: Fracture-specific algorithms were generated from July 2021 to December 2024 with accelerometer data from 42,623 races by 15,755 horses, including 54 races by 23 horses that subsequently suffered condylar fractures and 90 races by 31 horses that later sustained proximal sesamoid fractures. Fracture-specifi...
Castillo JDCR, Forte L, Elghandour MMMY, Maggiolino A, De Palo P, Ponce-Covarrubias JL, Salem AZM.Parasitic infections remain a major constraint to equine health and performance, and the worldwide rise of anthelmintic resistance is forcing a shift toward integrated parasite management and new complementary tools. Caesalpinia coriaria (Divi-divi) pods are exceptionally rich in tannins and have been proposed as a potential source of antiparasitic phytochemicals. This review summarizes the current evidence on C. coriaria, focusing on its relevance to equine gastrointestinal helminths. Most available data come from in vitro screening against ruminant nematode models (mainly Haemonchus contortu...
Kremer H, Bartling B.The nasal vestibule of numerous horses is pigmented. In the ventral part of the nasal vestibule, this pigmentation is often disturbed resulting in a clearly depigmented area. As nasal discharge passes this area, our study aimed at the practical quantification of the depigmented area in the nasal vestibule of horses and the analysis of its relation to nasal discharge and other parameters.This study included 74 horses (59 warmblood horses, 15 ponies) with pigmented nasal vestibule. When a depigmentation was found to be present in the ventral part, this area was photographed and quantified by use...
Ahmed HT, Berner D, Zhang Q, Verheyen K, Llabres-Diaz F, Peter VG, Chang YM.Fractures are a leading cause of morbidity and mortality in Thoroughbred racehorses, posing a significant threat to their welfare and careers. This study introduces a deep learning model specifically designed to facilitate fracture detection in equine athletes. By leveraging extensive training on human fracture data and refining the model with equine imaging, it highlights the transformative potential of transfer learning across species and medical contexts. This approach is not limited to equine fractures but could be adapted for use in detecting injuries or conditions in other veterinary spe...
Werner CA, Wimmer-Scherr CM, Schwarz BC.Equine laryngeal dysplasia (ELD) is the umbrella term for various malformations of laryngeal structures that arise from the 4th and 6th branchial arches during embryogenesis. The disease is rare and may be subclinical. In symptomatic patients with clinical signs, the clinical presentation is highly variable and is the result of functional limitations of the larynx as well as of the esophageal sphincter. The spectrum of signs may range from respiratory changes such as abnormal respiratory noise, coughing, and at times dyspnea all the way to poor performance, dysphagia, aerophagia, and colic. Th...
Schmidt S, Swagemakers JH, le Jeune SS.The cervical vertebral column in horses plays a crucial role in movement, posture, and performance and disorders affecting it can cause pain, ataxia, or lameness. This review discusses major acquired (traumatic, infectious, neoplastic) and degenerative (osteoarthritis, foraminal stenosis, intervertebral disc disease) conditions. Acquired lesions often arise from trauma, bacterial infection, or neoplasia, with clinical signs ranging from neck pain to neurologic deficits. Degenerative disorders, particularly osteoarthritis of articular process joints, are common in the caudal cervical spine and ...
Starrett A, Arnold CE, Burr A, Sarturi JO, Leatherwood JL, Pilla R, Awosile BB, Chaffin MK.To quantify gastrointestinal motility at 3 anatomic locations of the large colon in healthy horses fed 2 diets. Unassigned: 12 American Quarter Horses were enrolled in a prospective crossover study. Horses received either a complete pelleted diet fed at 1.35% body weight (BW) per day or Coastal Bermudagrass hay fed at 2% BW with 0.5% to 0.7% BW of complete pelleted feed. Each diet was fed for 13 days prior to motility assessment. Two ultrasonographers recorded the frequency of contractions at the sternal flexure of the large colon, left ventral colon, and cecum for 4 consecutive, 1-minute peri...
Hein M, Volkmann N, Probst J, Kemper N, Venner M.This retrospective report investigated whether starting racehorses' training and racing early is associated with a less successful and a shorter racing career. The data of 600 Thoroughbred racehorses from the German Racehorse Association's archiving programme were evaluated. The horses were classified into three groups regarding their different ages when starting training and racing: early training (16-24 months old)/early racing (two years old); early training/late racing (>two years old); and late training (25-30 months). Statistical models investigated effects on the horses' length of caree...
Vasco ACCM, Warren LK, Silva GM, Cuervo-Vivas W, Brandi RA, Silva VP, Lance JM, Dubeux JC, Wickens CL.Rhizoma peanut (RP, Arachis glabrata Benth) is an alternative legume forage to alfalfa (ALF, Medicago sativa L.) with less non-structural carbohydrates and crude protein. Yet, metabolic responses to consuming RP hay have never been evaluated in horses. Objective: The objective of this study was to investigate the effect of feeding RP 'Florigraze' hay on fecal and blood metabolic variables compared to alfalfa 'Legendary XHD' and bermudagrass (BMG, Cynodon dactylon L. 'Coastal') hays fed to maintenance horses. Methods: Six mature Quarter Horse geldings (596±40 kg) were randomly assigned to one ...
Henderson AR, Valverde A, Côté N, Sanchez A, Arroyo LG, Gu Y, Johnson R.To compare cardiopulmonary variables and recovery scores in isoflurane-anesthetized horses undergoing arthroscopy using two different intravenous (IV) lidocaine constant rate infusions (CRIs; 50 or 100 μg kg minute) under intermittent positive pressure ventilation (IPPV) or spontaneous ventilation (SV). Methods: Prospective, randomized, clinical study. Methods: A group of 30 client-owned horses, 8-156 months old (range), with body masses of 280-550 kg. Methods: Anesthesia protocol consisted of xylazine, ketamine and diazepam, and maintenance with isoflurane and a CRI of dexmedetomidine. All g...
Gentilini F, Ogundipe TG, Turba ME, Romagnoli N, Lambertini C, Pollera C, Cremonesi P, Stancampiano L.Gastrointestinal nematode infections significantly impact equine health and welfare, with rising anthelmintic resistance demanding alternative control strategies. Emerging evidence suggests that parasitic nematodes harbour distinct microbiomes, potentially influencing host-parasite dynamics and parasite survival. This study aimed to characterize and compare the microbiomes of equine gastrointestinal nematodes and their hosts, focusing on differences in composition, diversity, and core microbiota structure across different intestinal sites, nematode subfamilies, and sexes. Faecal and nematode s...
Kellerman TS, Marasas WF, Thiel PG, Gelderblom WC, Cawood M, Coetzer JA.Leukoencephalomalacia (LEM) was induced by the oral administration of fumonisin B1 (FB1) to 2 horses: a filly received 59.5 mg/kg of a 50% preparation of FB1, administered in 21 doses of 1.25-4 mg/kg over 33 days; a colt, 44.3 mg/kg of 95% pure FB1 in 20 doses of 1-4 mg/kg in 29 days. Both animals developed nervous signs such as apathy, changes in temperament, inco-ordination, walking into objects, and one showed paralysis of the lips and tongue. Characteristic lesions of LEM were present in the brains. These trials proved conclusively that FB1 can induce LEM in horses.
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...
Criado-Fornelio A, Martinez-Marcos A, Buling-Saraña A, Barba-Carretero JC.Molecular epizootiology of piroplasmids (Babesia spp., Theileria spp.) and Hepatozoon canis was studied in mammals from southern Europe (mainly from Spain, but also from Portugal and France). Partial amplification and sequencing of the 18s rRNA gene was used for molecular diagnosis. In some particular cases (B. ovis and B. bovis) the complete 18s rRNA gene was sequenced. Blood samples were taken from domestic animals showing clinical symptoms: 10 dogs, 10 horses, 10 cows, 9 sheep and 1 goat. In addition, DNA samples were isolated from blood of 12 healthy dogs and from spleen of 10 wild red fox...
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...
Frisbie DD, Trotter GW, Powers BE, Rodkey WG, Steadman JR, Howard RD, Park RD, McIlwraith CW.To evaluate the effect of arthroscopic subchondral bone microfracture on healing of large chondral defects in horses. Methods: Short- (4 months) and long-term (12 months) in vivo experimental chondral defect model. Methods: 10 horses, aged 2 to 5 years. Methods: Each horse had a 1 cm2 full-thickness chondral defect created in both radial carpal bones and both medial femoral condyles. One carpus and one femoral condyle of each horse had the subchondral bone plate under the defect perforated using an orthopedic awl. All horses were exercised, five horses were evaluated after 4 months and five ho...
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...
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...
Lomas AJ, Ryan CN, Sorushanova A, Shologu N, Sideri AI, Tsioli V, Fthenakis GC, Tzora A, Skoufos I, Quinlan LR, O'Laighin G, Mullen AM, Kelly JL....Tendon injuries represent a significant clinical burden on healthcare systems worldwide. As the human population ages and the life expectancy increases, tendon injuries will become more prevalent, especially among young individuals with long life ahead of them. Advancements in engineering, chemistry and biology have made available an array of three-dimensional scaffold-based intervention strategies, natural or synthetic in origin. Further, functionalisation strategies, based on biophysical, biochemical and biological cues, offer control over cellular functions; localisation and sustained relea...
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...
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 ...
Catlin BW.The clinical significance, Gram stain reaction, and genus affiliation of Gardnerella vaginalis have been controversial since Gardner and Dukes described the organism as the cause of "nonspecific vaginitis," a common disease of women which is now called bacterial vaginosis. The organism was named G. vaginalis when taxonomic studies showed that it was unrelated to bacteria in various genera including Haemophilus and Corynebacterium. Electron microscopy and chemical analyses have elucidated the organism's gram-variable reaction. Controversy over the etiology of bacterial vaginosis was largely res...
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...
Vidal MA, Kilroy GE, Lopez MJ, Johnson JR, Moore RM, Gimble JM.To characterize equine adipose tissue-derived stromal cell (ASC) frequency and growth characteristics and assess of their adipogenic and osteogenic differentiation potential. Methods: In vitro experimental study. Methods: Horses (n=5; aged, 9 months to 5 years). Methods: Cell doubling characteristics of ASCs harvested from supragluteal subcutaneous adipose tissue were evaluated over 10 passages. Primary, second (P2), and fourth (P4) passage ASCs were induced under appropriate conditions to undergo adipogenesis and osteogenesis. Limit dilution assays were performed on each passage to determine ...
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...
