"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.
Hellige M, Schröder C, Seehusen F, Cavalleri JM, Rohn K, Stadler P, Geburek F.Computed tomographic myelography (CTM) and radiographic myelography (RxM) are diagnostic for extradural spinal cord compression, but knowledge about the contrast distribution in flexion and normal position of nonaffected horses is lacking. Objective: (1) To determine the inter- and intravertebral ratios at C3-C4 of CTM in neutral and flexed positions in Warmbloods. (2) To compare the diameters of the spinal cord and the contrast columns at C3-C4 between neutral and flexed positions in CTM and RxM. (3) To evaluate the variability of measurements. Methods: Terminal in vivo method-comparison stud...
Sanigavatee K, Wonghanchao T, Poochipakorn C, Pongnarudech P, Suchairat T, Jitsopin S, Wanichayanon B, Sripiboon S, Chanda M.Long-distance road transport is known to be stressful for horses, with most research conducted in temperate climates. This study investigated horses' stress responses during long-distance transport before and after a jumping competition in a tropical environment. Ten healthy horses (aged 7.9 ± 1.9 years) were studied. Blood cortisol concentrations, haematology, and heart rate variability (HRV) were monitored during outbound (OTJ) and inbound journeys (INJ). Cortisol concentrations increased five minutes after unloading and remained elevated for up to 180 minutes in the OTJ (P < 0.05-0.001)...
Argue BJ, Labens R.Campdrafting is a unique Australian cow horse sport, which evolved from mustering cattle and is one of Australia's fastest growing equine sports. This discipline is associated with its own unique set of musculoskeletal injuries yet to be reported. Objective: To describe the prevalence, anatomical location, and diagnostic modality used to localise lameness in campdrafting horses to better assist efficient orthopaedic management of the campdraft horse. Methods: Retrospective case series. Methods: Medical records were examined from one private practice equine group and one university veterinary h...
Gazzano V, Curadi MC, Capsoni S, Baragli P, Kêdzierski W, Cecchi F, Gazzano A.In humans, aging is often accompanied by cognitive decline, as seen in Alzheimer's disease. In contrast, the aging process in horses remains poorly characterized. This study aims to explore the presence of blood-based biomarkers associated with cognitive degeneration in this species. Twenty-three Arabian horses were enrolled, and 5 mL of blood was collected from each to measure serum levels of β-amyloid peptides (Aβ40 and Aβ42) and phosphorylated tau protein (pTau181), both considered reliable indicators of cognitive impairment in other species. Aβ42 was undetectable in all samples, while ...
Vaughan B, McKerney ER, Wollenberger C, Cloninger A, Spriet M, Galuppo L, Stover SM.Humeral stress fractures in racehorses can progress to catastrophic fracture if unrecognised. Scintigraphy is the gold standard diagnostic technique but is limited by accessibility and cost. It was hypothesised that ultrasonography could be used to visualise caudoproximal humeral stress fractures. Objective: To determine the utility of ultrasonography to identify caudoproximal humeral stress fractures in racehorses. Methods: Clinical case series. Methods: Seven racehorses that had a clinical history consistent with the presence of a humeral stress fracture were examined using humeral ultrasono...
Ryan CA, Berry DP, Bugno-Poniewierska M, Burke MK, Raudsepp T, Egan S, Doyle JL.Autosomal trisomy, a genetic disorder characterized by the presence of an extra autosome, is a rare but important chromosomal abnormality in horses, often associated with infertility, developmental abnormalities, and reduced life expectancy. This study represents the largest population-level screening for autosomal trisomy in horses; the analysis used single nucleotide polymorphism (SNP) panel genotype intensity data from 17,078 horses, 6601 of which were juveniles (i.e., ≤12 months of age) when genotyped. Using methodologies adapted from similar screening studies in cattle, the only aneuplo...
Collins E, Barr E, Zhang C, Steadman M, Gilger B, Henriksen ML.To describe the most efficient topical horizontally centrifuged platelet-rich fibrin (H-PRF) treatment protocol for equine ulcerative keratitis (EUK) that is easy to use, and to report the preliminary concentration of growth factors and cytokines in equine H-PRF. Unassigned: 5 client-owned horses diagnosed with EUK were enrolled over an 11-month period. Unassigned: 3 horses were geldings, and 2 were mares. The mean (± SD) age was 5.95 ± 5.01 years. The owners' main goal was to avoid surgery for EUK. Unassigned: H-PRF was used in 3 different protocols: solid H-PRF, sutured to the EUK area (n ...
Tolnai CH, Forgách P, Marosi A, Fehér O, Paszerbovics B, Tenk M, Wagenhoffer Z, Kutasi O.In the last three decades, West Nile virus (WNV, Flaviviridae, Orthoflavivirus genus) has become one of the most important encephalitic agents worldwide, causing substantial numbers of cases in humans and horses every year by re-emerging in endemic areas and emerging in new territories. It is considered that after natural WNV infection, humans and birds develop long-term immunoprotection, but data on immunoprotection in horses is scarce. Objective: West Nile virus infection provides long-term humoral immunity in subclinically infected horses. Methods: Client-owned, naturally WNV subclinically ...
Berni P, Del Bue M, Conti V, Andreoli V, Ramoni R, Angelone M, Squassino GP, Bari E, Torre ML, Rinaldi M, Dotti S, Rossi R, Yusuf I, Mauri P....Most in vivo studies on MSC-secretome for osteoarthritis (OA) have relied on animal models, using products lacking pharmaceutical quality, not formulated for clinical use, and insufficiently characterized, limiting knowledge of its effectiveness. This study reports veterinary clinical trials on dogs and horses with spontaneous OA: in dogs (26 subjects), the trial is randomized, double-blinded, and controlled; in horses, 5 clinical cases were treated for safety assessment. Treatment consisted of hyaluronic acid with either lyosecretome - a freeze-dried, injectable MSC-secretome obtained through...
Gozalo-Marcilla M, Redondo JI, Bettschart-Wolfensberger R, Domenech L, Doménech J, Johnston GM, Taylor PM.To report on the Confidential Enquiry into Perioperative Equine Fatalities 4 (CEPEF4). Methods: Confidential, observational, prospective, multicentre, cohort study. Methods: 47,396 horses/ponies undergoing general anaesthesia (GA). Methods: Characteristics of each GA (249 variables) were collected. Outcomes after seven days were ALIVE (or discharged), EUTHANASIA or DEAD. Logistic regression analysed patient demographics and the anaesthetic drugs (p < 0.05). Results: Data were collected from 47,396 GAs in 93 centres in 28 countries. Death rates were 1.2% overall, 0.6% for cases classified as NO...
Kholik K, Sukri A, Priscilia Riwu KH, Ayu IW, Dewi IN.The transmission of () containing virulent genes from animals to humans and the environment poses significant public health challenges. This study aimed to detect the virulence factor of the () in isolated from the feces of apparently healthy horses in the island of Sumbawa, Indonesia. The study utilized 52 fecal samples from a total horse population of 283, calculated using the disease detection formula. Fresh feces were collected immediately after excretion and placed in buffered peptone water for subsequent analysis. The samples were then isolated on eosin methylene blue media and identi...
Horne CR, Redding WR.The location of a suspensory ligament (SL) injury heavily influences the clinical presentation, prognosis, and treatment options. Diagnostic imaging is necessary to provide an accurate diagnosis and is critical to ensure the institution of the most appropriate treatment. The hindlimb proximal SL in particular can be challenging to diagnosis, carries a guarded prognosis, and typically requires aggressive treatment to achieve soundness.
Pelli A, Schütrumpf L, Büttner J, Blomeyer S, Gerlach K, Troillet A.Feeding disorders in horses may have various underlying causes. A thorough clinical examination of the oral cavity is essential for clarification and is often supplemented by imaging techniques such as oral endoscopy, radiography, and computed tomography (CT) of the head. Sonographic examinations of the head and oral cavity are less commonly described diagnostic methods for the investigation of feeding disorders. This case report describes 2 horses presented to the clinic due to impaired feed intake. In both cases the radiographic examination of the head did not reveal any abnormalities relate...
Munoz Moran JA.This study was performed to evaluate the efficacy of intra-articular (IA) injections of a combination of platelet rich plasma (PRP) and hyaluronic acid (HA) on joint effusion following arthroscopic removal of OCD in the tarso-crural joint (TCJ) in young Andalusian horses. Methods: Forty Andalusian horses diagnosed with OCD of the distal intermediate ridge of the tibia (DIRT) were included in the study. Horses enrolled in this study had persisting synovial effusion after arthroscopic removal of OCD in the TCJ. A subjective semi-quantitative effusion score was adopted in the study to define the ...
Beaumont A, Emond AL, Pourcelot P, Fayaubot L, Ravary-Plumioen B, Dupays AG, Desquilbet L, Denoix JM, Crevier-Denoix N.To quantify changes in the cross-sectional area (CSA) of the midmetacarpal superficial digital flexor tendon (SDFT) in young Trotters during training. Unassigned: In this experimental study, 12 healthy 3-year-old French Trotters, assigned to either a soft-track or a hard-track group, were trained for 4 months (June through September of 2012 and 2013). Both groups followed the same exercise program of increasing intensity. Ultrasonographic examinations of both forelimb SDFTs of each horse were performed before the beginning of training (D0), after 2 months of training (M2), and after 4 months o...
Foucaud M, Haegeman L, Kadic D, Vinardell T, Mariën T, Declercq J.To describe a direct arthroscopic approach of the distal pouch of the palmar/plantar recess of the fetlock to facilitate fragment removal, highlighting its advantages over previously described arthroscopic methods for the fetlock. Additionally, to evaluate and present a retrospective case series. Methods: Ex vivo and retrospective clinical study. Methods: A total of 25 fetlocks in 23 horses. Methods: A direct approach to the distal pouch of the palmar/plantar recess of the fetlock was developed on five cadaveric limbs. Arthroscopic anatomy and landmarks were examined. The approach was clinical...
Boado A, Pollard D, Dyson S.There is limited information about the orthopaedic health of dressage horses. This study aimed to document the orthopaedic status, lesion distribution, and evolution of injuries in 70 horses undergoing a minimum of five in-depth orthopaedic assessments at six-months' intervals. Warmblood (70.0%) and Iberian (24.3%) breeds predominated. The median lameness grade at initial examination was 2/5 (interquartile range 2,2; range 0,3). Hypermetria (42.9%) or hypermetria and weakness (12.9%) were observed at the initial examination and did not change over time. Metacarpophalangeal/metatarsophalangeal ...
Peeters MWJ, Ott S, van Veggel E, Berner D, Perrier M.Limited reports in the literature are available regarding desmitis of the palmar/plantar ligaments of the proximal interphalangeal joint (PL-PIPJ); the clinical significance of such injuries is unknown. Objective: To describe the ability to differentiate the PL-PIPJ on low-field magnetic resonance (MR) examination. To describe the injury characteristics of the PL-PIPJ on MR examination and the correlation with clinical features and lameness. Methods: Retrospective case series. Methods: Data and MR images of 29 horses were collected from the databases of three institutions. Horses were included...
Coelho C, Vintem C, Silva AS, Santos C, Santos AM, Leite A, Souza V, Siqueira R, Filho HCM, Simões J.The present work aimed to evaluate the influence of a training programme on energy expenditure (EE), cost of transport (COT, cardiac beats to move the body mass during exercise) and metabolic power (Pmet) in young Purebred Lusitano horses used in dressage. With this purpose, nine male horses, ~4 years old, were evaluated before (M1) and after 6 weeks (M2) of a training programme that included 40-80 min of preparatory dressage exercises, 6×/week, individually adjusted. In M1 and M2, the animals were examined in a dressage field test (DFT), when heart rate (HR) and respiratory rate (RR), body...
Everts RE, Caron R, Foster G, McLoone K, Martin K, Brooks SA, Lafayette C.The roan coat color is described as the dispersion of white hairs within an otherwise solid background color coat. This phenotype is primarily expressed on the body of the horse, with the head and legs exhibiting few to no white hairs. Previous studies mapped the locus for roan to the KIT region and observed linked variants in a small number of breeds. However, utilizing those linked markers to determine the roan genotype in other breeds has seen limited success. In this communication we identify a second roan allele (RN2) which, in conjunction with a previously observed roan allele (RN1) disc...
Sales NAA, Carvalho JRG, Littiere TO, Costa GB, Silva ACY, Rodriguez IDM, Castro CM, Anjos LS, Ottati ACM, Alcaide JA, Ramos GV, Ferraudo AS....Whole-body vibration (WBV) has the potential to enhance post-exercise recovery in humans. Heart rate variability (HRV), a well-established biomarker of cardiac autonomic regulation (CAR), provides insight into autonomic reactivity during recovery from exercise. Objective: To investigate CAR in healthy horses during post-exercise recovery following an acute intensive exercise bout (AIEB) with WBV intervention. Methods: A single AIEB was prescribed at velocities corresponding to lactate threshold (VLT), and the eight horses performed on treadmill with 5 % slope, 2 min at 110 % VLT followed by 3 ...
Jonsdottir S, Stefansdottir SB, Mirkovitch J, Ziegler A, Torsteinsdottir S, Marti E.Insect bite hypersensitivity (IBH) is an IgE-mediated dermatitis in horses caused by bites of spp. The allergens are salivary gland proteins from these insects, and nine major allergens from have been identified and expressed in . However, proteins expressed in procaryotic systems have limitations in cellular assays, particularly in functional assays assessing the allergen-induced release of mediators , such as sulphidoleukotrienes (sLT) from basophils. The aims of the study were to produce functional allergens in insect cells, to assess their allergenicity using a sLT release assay, and to...
Dosi M, Scott L, Payne H, Poldy J, Keen J, McGorum B, Malbon A, Morgan R.Hyperinsulinaemia (HI) is an important feature of Equine Metabolic Syndrome (EMS). It has been suggested that reduced hepatic clearance of insulin contributes to HI, particularly in humans affected by metabolic dysfunction-associated steatotic liver disease (MASLD). Objective: In obese horses with HI, insulin clearance is impaired and associated with MASLD. Methods: Tissue samples were collected at post-mortem from clinically well-characterized horses with HI (n = 13; basal insulin > 20 mIU/l) and without HI (control; n = 20). Methods: Retrospective observational study. Molecular d...
Dai F, Toson M, Bertotto D, Dalla Costa A, Heinzl EUL, Lega F, Minero M, Padalino B, Stefani AL, Trestini S, Maietti F, Zonta G, Di Martino G.The present study aimed to evaluate the effects of self-loading training on the overall stress response during pre-slaughter transportation in slaughter horses. Thirty-two slaughter horses were divided into two groups: the control group (CG) and the Trained Group (TG). For six weeks, the TG horses were trained to self-load using a method based on target training and shaping. Animals from both groups were transported to the same slaughterhouse in small groups on different days using the same truck along the same route. The baseline and post-transportation values of the eye temperature and fecal...
Janczarek I, Gazda I, Barłowska J, Kurnik J, Łuszczyński J.It is assumed that horses have a strong herd instinct that cannot be suppressed by any form of social support from humans. The aim of this study was to assess the behaviour and heart rate parameters of horses that received various forms of human support during short-term social isolation. The research material consisted of 12 clinically healthy recreational warmblood mares and geldings. The test was carried out four times. The research test consisted of two parts, which began in the presence of accompanying horses and under conditions of social isolation, with and without support provided by a...
Abbas I, Ahmed F, Muqaddas H, Alberti A, Varcasia A, Sedda L.Climate change can cause spatio-temporal shifts in the epidemiology of various vector borne pathogens, especially in vulnerable areas such as the Mediterranean Basin (MB). Among these pathogens, the West Nile virus (WNV) became endemic in the region. This systematic review and meta-analysis study summarizes WNV epidemiology, molecular characteristics, and surveillance in various MB countries, relying on data and scientific articles on WNV published during 2010-2023. The number of published articles varied across the three MB subregions: Southern Europe (n = 153), North Africa (n = 33), and...
Ribeiro RM, Oliveira TO, Ribeiro DSF.The use of thermal cameras in horses has proven effective for monitoring surface body temperature non-invasively, enabling the early identification of disease and inflammation. This study evaluated the agreement between a thermal camera compared to an infrared thermometer in the measurement of surface temperatures of 60 healthy horses (27 mares, 33 stallions; 7.88 ± 4.01 years; 466 ± 50.1 kg). Measurements were taken at the neck, thorax, and coronary band between 8:00-9:00 a.m., under controlled environmental conditions. Analysis revealed strong correlations between the two methods at the co...
Parra-Moyano LA, Cedeño A, Darby S, Johnson JP, Gomez DE.The effectiveness of the peritoneal fluid L-lactate-to-total solids ratio (PFL:PFTS) as a diagnostic marker for strangulating lesions of the small intestine (SI) and large colon (LC) has not been investigated. Objective: Describe and compare the PFL:PTFS and blood lactate (BL), peritoneal fluid lactate (PFL) and PFL:BL difference and PFL:BL ratio of horses with SI and LC strangulating (SO) and non-strangulating (NSO) obstructions and determine sensitivity and specificity to predict SO. Methods: A total of 282 horses, 117 with SI lesions (59 classified as SINSO and 58 as SISO), and 165 with LC ...
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...
Ewers C, Bethe A, Stamm I, Grobbel M, Kopp PA, Guerra B, Stubbe M, Doi Y, Zong Z, Kola A, Schaufler K, Semmler T, Fruth A, Wieler LH, Guenther S.To discern the relevance of ST648 extended-spectrum β-lactamase (ESBL)-producing Escherichia coli as a putative new group of multiresistant and extraintestinal pathogenic strains in animals, its frequency, ESBL types, antimicrobial resistance patterns and virulence gene (VG) profiles should be determined and compared with ST131 strains from the same collection of strains. Methods: ESBL-producing E. coli isolates (n = 1152), consecutively sampled from predominantly dogs, cats and horses between 2008 and 2011, were assigned to a phylogenetic group by PCR. Partial multilocus sequence typing was ...
Biewener AA.The stresses acting in muscle-tendon units and ligaments of the forelimb and hindlimb of horses were determined over a range of speed and gait based on recordings of ground reaction forces and limb kinematics. Maximum stresses of 40-50 MPa were calculated to act in several of the principal forelimb (superficial digital flexor (SDF), deep digital flexor (DDF), ulnaris lateralis (UL) and flexor carpi ulnaris/radialis (FCU/R)) and hindlimb tendons (plantaris, DDF) at the fastest galloping speeds recorded (up to 7.4 m s-1). Smaller stresses were found for the gastrocnemius (GAST) tendon (30 MPa) a...
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...
Autorino GL, Battisti A, Deubel V, Ferrari G, Forletta R, Giovannini A, Lelli R, Murri S, Scicluna MT.During the late summer of 1998, veterinary authorities in Tuscany, Italy, received reports of cases of neurologic disease among horses residing in a large wetland area located in the provinces of Florence and Pistoia. West Nile virus was isolated from two of the six horses that died or were euthanized. A retrospective epidemiologic study identified 14 clinical neurologic cases that occurred from August 20 to October 6 (attack rate of 2.8%). A serologic survey conducted over a 700-km2 area in stables with and without apparent clinical cases confirmed a wider spread of the infection, with an ove...
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...
Frost MJ, Zhang J, Edmonds JH, Prow NA, Gu X, Davis R, Hornitzky C, Arzey KE, Finlaison D, Hick P, Read A, Hobson-Peters J, May FJ, Doggett SL....To determine the cause of an unprecedented outbreak of encephalitis among horses in New South Wales, Australia, in 2011, we performed genomic sequencing of viruses isolated from affected horses and mosquitoes. Results showed that most of the cases were caused by a variant West Nile virus (WNV) strain, WNV(NSW2011), that is most closely related to WNV Kunjin (WNV(KUN)), the indigenous WNV strain in Australia. Studies in mouse models for WNV pathogenesis showed that WNV(NSW2011) is substantially more neuroinvasive than the prototype WNV(KUN) strain. In WNV(NSW2011), this apparent increase in vir...
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...
Sutton S, Clutterbuck A, Harris P, Gent T, Freeman S, Foster N, Barrett-Jolley R, Mobasheri A.Osteoarthritis (OA) is one of the most common and disabling chronic joint disorders affecting horses, dogs and humans. Synovial inflammation or synovitis is a frequently observed phenomenon in osteoarthritic joints and contributes to the pathogenesis of OA through formation of various catabolic and pro-inflammatory mediators altering the balance of cartilage matrix degradation and repair. Catabolic mediators produced by the inflamed synovium include pro-inflammatory cytokines, nitric oxide, prostaglandin E(2) and several neuropeptides, which further contribute to the pathogenesis of OA by incr...
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.
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 ...
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 ...
McIlwraith CW, Frisbie DD, Kawcak CE, Fuller CJ, Hurtig M, Cruz A.Equine models of osteoarthritis (OA) have been used to investigate pathogenic pathways of OA and evaluate therapeutic candidates for naturally occurring equine OA which is a significant clinical disease in the horse. This review focuses on the macroscopic and microscopic criteria for assessing naturally occurring OA in the equine metacarpophalangeal joint as well as the osteochondral fragment-exercise model of OA in the equine middle carpal joint. Methods: A review was conducted of all published OA studies using horses and the most common macroscopic and microscopic scoring systems were summar...
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...
Marklund L, Moller MJ, Sandberg K, Andersson L.The melanocyte-stimulating hormone receptor gene (MC1R) is the major candidate gene for the chestnut coat color in horses since it is assumed to be controlled by an allele at the extension locus. MC1R sequences were PCR amplified from chestnut (e/e) and non-chestnut (E/-) horses. A single-strand conformation polymorphism was found that showed a complete association to the chestnut coat color among 144 horses representing 12 breeds. Sequence analysis revealed a single missense mutation (83Ser-->Phe) in the MC1R allele associated with the chestnut color. The substitution occurs in the second ...
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....
