"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.
Van Cleemput J, Poelaert KCK, Laval K, Vanderheijden N, Dhaenens M, Daled S, Boyen F, Pasmans F, Nauwynck HJ.β-Defensins protect the respiratory tract against the myriad of microbial pathogens entering the airways with each breath. However, this potentially hostile environment is known to serve as a portal of entry for herpesviruses. The lack of suitable respiratory model systems has precluded understanding of how herpesvirus virions overcome the abundant mucosal β-defensins during host invasion. We demonstrate how a central alphaherpesvirus, equine herpesvirus type 1 (EHV1), actually exploits β-defensins to invade its host and initiate viral spread. The equine β-defensins (eBDs) eBD1, -2, and -3...
Alonso JM, Rosa GDS, Santos B, Guerra S, Ribeiro M, Watanabe MJ, Alves A, Rodrigues C, Takahira RK, Hussni CA.Intraperitoneal administration of ceftriaxone maintains therapeutic abdominal concentrations for 24 hours in healthy horses. Therefore, it is a possible treatment for septic peritonitis. The aim of this study was to evaluate the efficacy of ceftriaxone as an adjuvant treatment in horses with septic peritonitis. Methods: Twenty-six horses with clinical signs, sonography and/or laboratory findings of septic peritonitis were included. Peritoneal fluid was collected for microbiological culture and in vitro microbial sensitivity profile assessment. Daily intraperitoneal administration of ceftriax...
Lambertini C, Bombardi C, Zannoni A, Bernardini C, Dondi F, Morini M, Rinnovati R, Spadari A, Romagnoli N.Proteinase activated receptor 4 (PAR) in the gastrointestinal tract is involved in the regulation of inflammation and pain pathways. The aim of the present study was to evaluate the distribution and expression of PAR in the jejunum of healthy horses and in the pathologic tracts from horses undergoing surgery for herniation of the small intestine through the epiploic foramen. Eight healthy horses (Group H) and eight horses with epiploic hernia (Group EH) were included; the jejunum samples were collected at the slaughter or intraoperatively after enterectomy, respectively. To evaluate PAR expres...
Küls N, Trujanovic R, Otero PE, Larenza-Menzies MP.Colic surgery is one of the most painful procedures carried out in horses. Common strategies to alleviate immediate postsurgical abdominal pain include the administration of potent systemic analgesics; however, these may cause unwanted adverse effects such as cardiovascular depression, ileus, and ataxia. The administration of local anesthetics at the incision site in form of an ultrasound-guided subcostal transversus abdominis plane (TAP) block may therefore be preferred to provide adequate analgesia without significant side effects. To date, no technique for a TAP block in horses undergoing m...
Freeman DE, Mooney A, Giguère S, Claire J, Evetts C, Diskant P.Measurements of water consumed by fed healthy horses might not apply to horses that are unwilling or unable to drink or are not fed for any reason. Objective: To examine the effects of feed deprivation on voluntary water consumption compared with fed conditions. Methods: In vivo experiment. Methods: Eight healthy adult Thoroughbred geldings were used in a randomised crossover design so that each horse served as its own control for fed vs feed-deprived conditions. Water intake, bodyweight, physical findings and vital signs were measured during 4 days of feeding and 4 days of feed deprivation....
Mellor DJ.A proposition addressed here is that, although bitted horses are viewed by many equestrians as being largely free of bit-related mouth pain, it seems likely that most behavioural signs of such pain are simply not recognised. Background information is provided on the following: the major features of pain generation and experience; cerebrocortical involvement in the conscious experience of pain by mammals; the numerous other subjective experiences mammals can have; adjunct physiological responses to pain; some general feature of behavioural responses to pain; and the neural bases of sensations g...
Maia MPM, Weber SH, Bastos LFC, Michelotto PV.This study aimed to investigate the prevalence of juvenile osteochondral conditions (JOCCs) in yearling Thoroughbred (TB) racehorses in Southern Brazil, as well as to examine the same animals studied as weanlings by Bastos et al. (2017) and compare the radiographic findings for the two ages. Radiographs of 76 male and female TB yearlings from Paraná State, Southern Brazil, were investigated. The proximal interphalangeal, metacarpophalangeal/metatarsophalangeal (MC/MT), tarsal, and femorotibial (FT) joints were evaluated using 24 radiographic projections. The evaluation consisted of a severit...
Day P, Collins L, Horan K, Weller R, Pfau T.Tungsten road nails are commonly used by farriers to increase grip between the hoof and the ground surface. There is limited evidence relating the use of road nails to the fundamental mechanics of movement. Grip is important for efficient deceleration on landing and subsequent propulsion, but this must be balanced against an amount of slip to divide the landing force into horizontal as well as vertical subcomponents. Here, we conducted an intervention study to quantify the effect of lateral heel road nail placement on weight bearing and propulsion in 10 horses trotting on tarmac. Wireless iner...
Parsons Aubone AM, Bisiau CM, McCue PM, Bouma GJ.Mammals have a circadian rhythm that is synchronized by a master clock located in the hypothalamic suprachiasmatic nucleus (SCN). The SCN regulates additional clocks located in peripheral tissues, including some involved in endocrine or reproductive functions. Studies in humans and mice report that molecular clocks also exist in the placenta. However, little is known about the presence of "Clock genes," namely Circadian Locomotor Output Cycles Kaput (CLOCK), Brain and Muscle Arnt-Like 1 (BMAL1), Period 1 (PER1), Period 2 (PER2), Cryptochrome 1 (CRY1), and Cryptochrome 2 (CRY2), in equine place...
Spears JW, Lloyd KE, Siciliano P, Pratt-Phillips S, Goertzen EW, McLeod SJ, Moore J, Krafka K, Hyda J, Rounds W.Forty-eight Quarter Horse geldings (3 to 8 yr of age) were used to determine the effects of dietary chromium (Cr), in the form of Cr propionate (Cr Prop) on insulin sensitivity. Horses were blocked by age, body condition score, and glucose response to concentrate feeding on day 0 and randomly assigned to treatments. Treatments consisted of 0, 2, 4, or 8 mg Cr/d from Cr Prop. Horses were fed daily a concentrate mix at a rate of 0.2 kg/100 kg body weight (BW) and grass hay at 1.75 to 2.0 kg/100 kg BW. All horses were fed the control diet for 7 d prior to the initiation of the study. After an ove...
Li B, He X, Zhao Y, Bai D, Li D, Zhou Z, Manglai D.Numerous studies have shown that microRNAs (miRNAs) are essential for testicular development and spermatogenesis. In order to further characterise these physiological processes, three immature and three mature testes of the Mongolian horse were collected and six libraries were established. Using small RNA sequencing technology, 531 mature miRNAs were identified, including 46 novel miRNAs without previously ascribed functions. Among the 531 miRNAs, 421 were expressed in both immature and mature libraries, 65 miRNAs were found solely in immature testis libraries and 45 miRNAs were found solely i...
Rostang A, Desjardins I, Espana B, Panzuti P, Berny P, Prouillac C, Pin D.This study aimed to investigate both the pharmacokinetic behavior and tolerance of methotrexate (MTX) in horses to design a specific dosing regimen as a new immunomodulatory drug for long-term treatment. To determine the primary plasma pharmacokinetic variables after single intravenous, subcutaneous or oral administration, six horses were administered 0.3 mg/kg MTX in a crossover design study. After a 10-week washout, MTX was administered subcutaneously to three of the six previously treated horses at a dose of 0.3 mg/kg once per week for 3 months. In both studies, MTX and metabolite concen...
Jaworska J, Jaworski Z, McDonnell SM, Górecka-Bruzda A.Infanticide, related to a stallion's aggression toward a foal sired by another stallion, and feticide related to a new stallion's aggression and/or pheromonal influence (the Bruce effect) inducing loss of a fetus sired by another stallion, a female's counteraction to infanticide, have been proposed for domestic horses (Equus caballus) in human-managed conditions. The aim of the present study was, in conditions close to natural, to investigate the influence of the natural succession of a harem stallion on the mares' subsequent reproductive performance. In a population of semi-feral Konik polski...
Vengust M, Jager MC, Zalig V, Cociancich V, Laverack M, Renshaw RW, Dubovi E, Tomlinson JE, Van de Walle GR, Divers TJ.Equine parvovirus-hepatitis (EqPV-H) has been proposed as the aetiological cause of Theiler's disease, also known as serum hepatitis. EqPV-H-associated Theiler's disease has not been previously reported in Europe. Objective: To determine whether EqPV-H infection was associated with a 2018-2019 outbreak of Theiler's disease in four horses on a studfarm. Methods: Descriptive case series. Methods: The medical records of four horses from the same farm diagnosed with fatal Theiler's disease were examined retrospectively. Information collected included a clinical history, physical examination findin...
Verhaar N, Pfarrer C, Neudeck S, König K, Rohn K, Twele L, Kästner S.Pharmacological preconditioning of dexmedetomidine on small intestinal ischaemia/reperfusion injury has been reported in different animal models including horses. Objective: The objective was to assess if xylazine and lidocaine have a preconditioning effect in an experimental model of equine jejunal ischaemia. Methods: Terminal in vivo experiment. Methods: Ten horses under general anaesthesia were either preconditioned with xylazine (group X; n = 5) or lidocaine (group L; n = 5). A historical untreated control group (group C; n = 5) was used for comparison. An established experimental mo...
Gy C, Leclere M, Bélanger MC, Allano M, Beauchamp G, Lavoie JP.Monensin is highly toxic to horses and inadvertent ingestion can result in cardiac injury and death. Objective: To describe sequelae of monensin ingestion and to determine clinical predictors of outcome. Methods: Observational clinical study. Methods: Physical examination, electrocardiogram and echocardiography were performed on 76 horses accidentally exposed to monensin-contaminated feed. Four horses were examined within 14 days of exposure (acute period), 29 horses were examined between 15 and 45 days post-exposure (subacute period) and 70 horses were examined 4-10 months after exposure ...
Gurgul A, Jasielczuk I, Semik-Gurgul E, Pawlina-Tyszko K, Szmatoła T, Polak G, Bugno-Poniewierska M.The current role of the horse as a companion animal resulted in a decrease of interest in breeding and usage of draft horses. This meant that the population of cold-blooded horses in Poland has been dramatically reduced during the last decades. To avoid impoverishment of the gene pool of the local horse population, a conservation program was established which involves draft horses and other local horse breeds. The draft horses bred in Poland can be subdivided in a few horse types of which the most widespread and consolidated are Sztumski and Sokólski horses. These two subpopulations are pheno...
Selim A, Radwan A, Arnaout F.West Nile Virus (WNV) is a flavivirus, mosquito-borne infection and have public health importance worldwide. WNV infection have highly significant impact on animal and human health. The virus has been detected serologically in Egypt among equids. Therefore, the aim of the present study to investigate the serological situation of WNV among horse in north of Egypt and identification of WNV in vector. The serological survey was conducted on 500 serum samples that collected from horses from four governorates at north of Egypt. The infection rate was non-significant differed between four localities...
Crandall A, Hopster K, Grove A, Levine D.In horses undergoing castration, direct comparison of intratesticular lidocaine vs mepivacaine as analgesic adjuncts has not yet been analysed. Objective: To compare the effects of intratesticular lidocaine and mepivacaine during equine castration using the Henderson drill under total intravenous anesthesia. Methods: Randomised, double-blinded clinical study. Methods: Thirty-four stallions were anaesthetised using xylazine-ketamine and randomly selected to receive 10 mL either lidocaine or mepivacaine injected into each testicle. Both surgeon and anaesthetist were blinded to the selected trea...
Bacci B, Stent AW, Walmsley EA.Lymphoma is the most common intestinal neoplasm in horses, but its clinical-pathological features are poorly characterized. Primary intestinal lymphoma was diagnosed in 20 horses on biopsy samples and further confirmed by postmortem examination in 16 cases. Lymphoma was found in the small intestine in 12 of 20 (60%), in the colon in 5 of 20 (25%), and in both small and large intestines in 3 of 20 (15%) cases. Gross findings included thickening of the intestinal wall (45%), mural nodules or masses (30%), and both thickening and nodules (10%). Cases were classified according to the human World H...
Nomura M, Kuroda T, Tamura N, Muranaka M, Niwa H.Although Clostridioides difficile-associated diseases (CDAD) is considered to be associated with colitis in horses, few studies have been performed with a focus on the characteristics of CDAD in thoroughbred racehorses. Between 2010 and 2018, a test for C. difficile was performed using faecal samples from 137 thoroughbred racehorses with colitis presenting with diarrhoea and fever. The mortality rate, clinical findings, predisposing factors and the selected treatments were investigated in a retrospective manner. Twenty-four cases were diagnosed as CDAD and 113 as non-CDAD. The mortality rate w...
Campaigners are working hard to preserve access routes through the countryside for ramblers, dog walkers and horse riders. They invite you to join them. reports.
Kuzmina ТА, Zvegintsova NS, Yasynetska NI, Kharchenko VA.Resistance of strongylids in domestic horses to benzimidazole anthelmintics (BZ) has been detected worldwide; however, information on the presence of BZ-resistance in wild equids has not been published to date. The purpose of this study was to analyze the manifestations of the BZ resistance in strongylids in domestic and wild equids kept in the Askania Nova Biosphere Reserve, Ukraine. Four species of equids: domestic horses and Shetland ponies (Equus caballus), donkeys (E. asinus), plains zebras (E. burchelli) and Grévy’s zebras (E. grevyi) kept under semi-free conditions were examined usin...
Steuer AE, Stewart JC, Barker VD, Adams AA, Nielsen MK.The role of the immune response to cyathostomin infections in horses remains unknown. Intestinal goblet cell hyperplasia has previously been noted as a component in cyathostomin infection; however, the function is unclear. The goal of this study was to evaluate the local and systemic gene expression to cyathostomin infections following larvicidal treatment and explore their relation to goblet cells. Thirty-six ponies with naturally acquired cyathostomin infections were randomly allocated into three groups: fenbendazole-treated (10 mg/kg PO 5 days), moxidectin-treated (0.4 mg/kg PO once) and...
Totorikaguena L, Olabarrieta E, Lolicato F, Romero-Aguirregomezcorta J, Smitz J, Agirregoitia N, Agirregoitia E.The cannabinoid (CB) system has been involved in many aspects of reproduction and it is known that the systemic chronic use of exogenous CBs are deleterious to reproductive processes. Even so, it is not known what happens in relation to the physiology of the ovary when CB receptors are absent. The present study investigated the effect of the lack of CB1 and CB2 receptors in mice ovarian morphology, folliculogenesis, oocyte retrieval, and oocyte maturation and evaluated the use of Δ9-tetrahydrocannabinol (THC) on oocyte in vitro maturation (IVM) by comparing classical IVM and two-step IVM by a...
Decloedt A, Ven S, De Clercq D, Rademakers F, van Loon G.Aortic regurgitation (AR) may lead to left ventricular (LV) dilatation, cardiac arrhythmias and heart failure. Close follow-up of horses with AR is therefore paramount to detect onset of cardiac decompensation. The aim of this study was to examine whether two-dimensional speckle tracking (2DST) can be used to detect altered myocardial function in horses with chronic AR compared to control horses. Speckle tracking was performed on short axis and long axis images of the LV in 29 healthy Warmblood horses and 57 Warmblood horses with AR. Radial, circumferential and longitudinal strain, strain rate...
Tomlinson JE, Jager M, Struzyna A, Laverack M, Fortier LA, Dubovi E, Foil LD, Burbelo PD, Divers TJ, Van de Walle GR.Equine parvovirus-hepatitis (EqPV-H) has recently been associated with cases of Theiler's disease, a form of fulminant hepatic necrosis in horses. To assess whether EqPV-H is the cause of Theiler's disease, we first demonstrated hepatotropism by PCR on tissues from acutely infected horses. We then experimentally inoculated horses with EqPV-H and 8 of 10 horses developed hepatitis. One horse showed clinical signs of liver failure. The onset of hepatitis was temporally associated with seroconversion and a decline in viremia. Liver histology and in situ hybridization showed lymphocytic infiltrate...
Smith R, Önnerfjord P, Holmgren K, di Grado S, Dudhia J.The diagnosis of tendon injury relies on clinical signs and diagnostic imaging but imaging is subjective and does not always correlate with clinical signs. A molecular marker would potentially offer a sensitive and specific diagnostic tool that could also provide objective assessment of healing for the comparison of different treatments. Cartilage Oligomeric Matrix Protein (COMP) has been used as a molecular marker for osteoarthritis in humans and horses but assays for the protein in tendon sheath synovial fluids have shown overlap between horses affected by tendinopathy and controls. We hypot...
de Lagarde M, Fairbrother JM, Arsenault J.Although antimicrobial resistance is an increasing threat in equine medicine, molecular and epidemiological data remain limited in North America. We assessed the prevalence of, and risk factors for, shedding multidrug-resistant (MDR) and extended-spectrum β-lactamase (ESBL) and/or AmpC β-lactamase-producing in healthy horses in Quebec, Canada. We collected fecal samples in 225 healthy adult horses from 32 premises. A questionnaire on facility management and horse medical history was completed for each horse. Indicator (without enrichment) and specific (following enrichment with ceftriaxone)...
Darnaud SJ, Southwood LL, Aceto HW, Stefanovski D, Tomassone L, Zarucco L.It is our clinical impression that age and incision length are more strongly associated with surgical site infection (SSI) following colic surgery than skin closure or wound protection method. Therefore, the objective of this observational clinical cohort study was to identify the risks for SSI in horses undergoing colic surgery. Data collection included pre-, intra-, and postoperative variables. Variables with P < 0.2 following univariable analysis were used in a logistic regression multivariable model. Variables with P <0.05 were included in the final model. Odds ratios (OR; 95% confid...
Mendez-Angulo JL, Mudge MC, Vilar-Saavedra P, Stingle N, Couto CG.To evaluate the use of citrated recalcified (nonactivated) thromboelastography (TEG) in healthy horses and horses with colitis and suspected coagulopathies. Methods: Prospective, observational study conducted between October 2007 and June 2009. Methods: Veterinary Teaching Hospital. Methods: Forty-five healthy adult horses and 12 sick adult horses with colitis and prolonged prothrombin time (PT) or activated partial thromboplastin time (aPTT). Methods: None. Results: Whole blood was collected on admission. Coagulation profile (PT, aPTT, platelet count, and fibrinogen concentration) and citrate...
Johnson AL, McAdams-Gallagher SC, Aceto H.The laboratory diagnosis of botulism in horses traditionally has relied upon the mouse bioassay (MBA). The accuracy of this test for the diagnosis of botulism in horses is unknown. Objective: Our goal was to determine the sensitivity, specificity, positive predictive value, and negative predictive value of the MBA on laboratory-processed fecal and gastrointestinal samples for foals and adult horses. Methods: Cases included all horses with a final clinical diagnosis of botulism that were admitted between 1986 and 2011 and had MBA testing performed. Controls included horses without botulism that...
Wilmink JM, van Herten J, van Weeren PR, Barneveld A.In accidental wounds, trauma and infection can result in dehiscence of primarily closed wounds and in sequestrum formation when cortical bone is exposed. In experimental studies, it has been shown that second intention healing is faster and occurs with less complications in ponies than in horses. Also, a greater initial inflammatory response was seen in ponies. Based on these experimental data, it was hypothesised that accidental wounds in ponies would heal with a lower incidence of wound dehiscence and/or sequestrum formation compared to horses. A retrospective study of 89 ponies and 422 hors...
Christensen JW, Ahrendt LP, Malmkvist J, Nicol C.The mechanisms underlying individual variation in learning are key to understanding the development of cognitive abilities. In humans and primates, curiosity has been suggested as an important intrinsic factor that enhances learning, whereas in domesticated species research has primarily identified factors with a negative effect on cognitive abilities, such as stress and fearfulness. This study presents the first evidence of a link between object-directed curiosity and learning performance in young horses in two very different learning tasks (visual discrimination and pressure-release). We exp...
Huff NK, Auer AD, Garza F, Keowen ML, Kearney MT, McMullin RB, Andrews FM.Sea buckthorn berries (Hippophae rhamnoides) are rich in vitamin C and E, carotenoids, flavonoids, fatty acids, plant sterols, lignans, and minerals. A feed supplement containing sea buckthorn berries might have efficacy in treatment and prevention of gastric ulcers in horses. Objective: To test the efficacy of a commercially available formulation of sea buckthorn berries and pulp (SeaBuck SBT Gastro-Plus) for treatment and prevention of gastric ulcers in stall-confined horses. Methods: Eight Thoroughbred and Thoroughbred-cross horses (3-10 years of age, 5 geldings and 3 mares, 380-600 kg body...
Pálsdóttir AM, Gudmundsson M, Grahn P.People with neurological disorders suffer from poor mobility, poor balance, fatigue, isolation and monotonous everyday activities. Studies show that equine-assisted interventions can improve their mobility and balance, but could these kinds of interventions also increase participants' activity repertoire and self-assessed health, and reduce their fatigue? The study was conducted as a prospective, controlled study with three cohorts followed for one year: intervention group ( = 14), control group Passive ( = 29), and control group Active ( = 147). Participants in the study were affected by neur...
Käsbohrer A, Schönberg A.The prevalence of B. burgdorferi, the causative agent of Lyme Borreliosis in humans, was determined in domestic animals living in Berlin. 189 dogs, 29 cats, 224 horses and 194 cows were investigated. Using the indirect immunofluorescence test (IFT) 5.8% of the dogs and 24.5% of the cows investigated showed a positive reaction at titres of 1:128 or higher. Horses and cats gave negative results. ELISA was more sensitive than IFT. 10.1% of the dogs, 16.1% of the horses and 66% of the local cows showed positive reaction. Domestic animals seem to be in contact with B. burgdorferi and can be a reser...
de Oliveira PB, Harvey TV, Fehlberg HF, Rocha JM, Martins TF, da Acosta ICL, Labruna MB, Faccini JLH, Albuquerque GR.Tick-borne spotted fever in Brazil is known to be caused by two agents, Rickettsia rickettsii and Rickettsia parkeri. Nothing was known about these agents in one area of the Atlantic rainforest biome of Bahia state, where during March to June 2016, 356 rural dogs and 69 horses were sampled and their sera were processed through indirect immunofluorescence assay against antigens of R. rickettsii, R. parkeri, Rickettsia amblyommatis and Rickettsia bellii. Ticks collected from these dogs and horses were molecularly tested for the presence of rickettsial DNA. Overall, 16.4% (58/356) dogs and 24.6% ...
Jørgensen E, Lazzarini G, Pirone A, Jacobsen S, Miragliotta V.Information on microscopic anatomy of equine skin is sparse. In horses, limb wounds often become chronic and/or non-healing whereas body wounds heal normally. These dissimilarities in healing patterns might be a product of different phenotypic characteristics of body and limb skin. The objective of this study was to investigate microscopic anatomy, epidermal thickness, keratinocyte proliferation and differentiation as well as the presence of mast cells in normal equine skin of body and limb. Methods: The study involved body and limb skin biopsies from six horses. Histological characteristics o...
Nomura M, Kuroda T, Tamura N, Muranaka M, Niwa H.Although Clostridioides difficile-associated diseases (CDAD) is considered to be associated with colitis in horses, few studies have been performed with a focus on the characteristics of CDAD in thoroughbred racehorses. Between 2010 and 2018, a test for C. difficile was performed using faecal samples from 137 thoroughbred racehorses with colitis presenting with diarrhoea and fever. The mortality rate, clinical findings, predisposing factors and the selected treatments were investigated in a retrospective manner. Twenty-four cases were diagnosed as CDAD and 113 as non-CDAD. The mortality rate w...
Ford JE, Home WA, Gibson DM.Horse Ig kappa genes have been characterized to determine whether there may be a structural basis for the low level of kappa expression in this species. The overall organization of the J kappa-C kappa locus is remarkably similar to that of the mouse and human loci. A single C kappa exon is separated by 2.9 kb from five J kappa segments, four of which seem functional and three of which are associated with canonical recombination signal sequences. A highly conserved intron enhancer was identified upstream of the C kappa exon and a single restriction fragment in horse genomic DNA hybridized stron...
Whalley JM, Ruitenberg KM, Sullivan K, Seshadri L, Hansen K, Birch D, Gilkerson JR, Wellington JE.Equine herpesviruses 1 and 4 (EHV-1 and EHV-4) cause equine respiratory disease worldwide. However, only EHV-1 is a cause of abortion and neurological disease, despite the two viruses having all 76 genes in common. In addition EHV-1 has a broader host range in cell culture than EHV-4, as exemplified by the rabbit kidney (RK) cell line that is permissive for EHV-1, but not for EHV-4. Here we describe that when EHV-4 produced in equine cells was inoculated onto RK cells expressing glycoprotein D of EHV-1 (RKgD1), infection developed as clusters of rounded cells, and this infectivity could be pas...
Bleumink-Pluym NM, Werdler ME, Houwers DJ, Parlevliet JM, Colenbrander B, van der Zeijst BA.A PCR for the detection of Taylorella equigenitalis, the causative agent of contagious equine metritis, was developed and evaluated. A genus-specific primer-probe set was derived from the 16S ribosomal DNA sequences. The PCR was specific and amplified a 585-bp product from all 64 available T. equigenitalis isolates. This PCR product hybridized with a specific probe in a dot spot assay. A variety of microorganisms from the genital tracts of horses or with a close phylogenetic relationship to T. equigenitalis did not yield a visible PCR product and were all negative in the dot spot hybridization...
Stepnik CT, Outerbridge CA, White SD, Kass PH.This retrospective study reports on the clinical presentation of equine atopic skin disease and evaluates response to treatment with allergen-specific immunotherapy (ASIT) based on intradermal testing and/or serum testing. Computerized medical records from January 1991 to December 2008 yielded 54 horses included in the study. Presenting clinical signs (CS) included urticaria (n=28), pruritus (n=8) or both (n=18). Forty-one of 54 horses received ASIT, and response to ASIT (n=32) was evaluated via telephone survey. Eighty-four per cent (n=27) of owners reported that ASIT reduced their horse's CS...
Hermanson JW.The extensor carpi radialis muscle of the horse is deceptive at first appearance. It has a fusiform shape similar to other forearm extensor muscles. The fiber arrangement also appears long and relatively parallel. However, it may contain two or more compartments that correlate with differing functional roles. Histochemical and immunocytochemical analysis of proximal and distal regions of the muscle (n = 9) demonstrate that the proximal portion of the muscle is composed of a mean of 13% type I, presumed slow twitch, and 61% type IIb, presumed fast twitch fibers. In contrast, the distal compartm...
Pujol R, Girard CA, Richard H, Hassanpour I, Binette MP, Beauchamp G, McDougall JJ, Laverty S.To measure the nerve fiber density in synovial membranes from healthy and OA equine joints and to investigate the relationship between synovial innervation and OA severity, synovial vascularity and synovitis. Twenty-five equine metacarpophalangeal joints were collected post-mortem. The joints were dissected and the macroscopic lesions of the articular cartilage were scored. Synovial membrane specimens (n = 50) were harvested, fixed, sectioned and scored histologically. Immunohistochemical staining and immunofluorescence with S-100 protein, that identifies nerve fibers, and ⍺-actin, that st...
Brown K, Moreton J, Malla S, Aboobaker AA, Emes RD, Tarlinton RE.The recently released draft horse genome is incompletely characterised in terms of its repetitive element profile. This paper presents characterisation of the endogenous retrovirus (ERVs) of the horse genome based on a data-mining strategy using murine leukaemia virus proteins as queries. 978 ERV gene sequences were identified. Sequences were identified from the gamma, epsilon and betaretrovirus genera. At least one full length gammaretroviral locus was identified, though the gammaretroviral sequences are very degenerate. Using these data the RNA expression of these ERVs were derived from RNA ...
Darlington RW, James C.Darlington, R. W. (St. Jude Children's Research Hospital, Memphis, Tenn.), and C. James. Biological and morphological aspects of the growth of equine abortion virus. J. Bacteriol. 92:250-257. 1966.-The growth of equine abortion virus (EAV) was studied by bioassay and electron microscopy in L-cell monolayer and suspension cultures, and in HeLa and BHK 21/13 cell monolayers. Results of virus assay (plaque-forming units) indicated that production of cell-associated virus (CAV) began at 6 to 9 hr after infection in all of the cell strains used. Virus release occurred 1 to 2 hr later. By 15 to 20 h...
Fenner K, Matlock S, Williams J, Wilson B, McLean A, Serpell J, McGreevy P.The Equine Behaviour Assessment and Research Questionnaire (E-BARQ) was developed to obtain quantitative data on the domestic equine triad: training, management and behaviour. It can be taken repeatedly, thus collecting longitudinal data to enable evaluation of how changes in a horse's training and management are reflected in that horse's behaviour over time and how these changes can impact horse welfare in the longer term. Questionnaire validation and reliability were tested by determining (a) whether an owner's subjective ratings of their horse's problematic behaviours or undesirable tempera...
Shin J, Ahn KS, Suh GH, Kim HJ, Jeong HS, Kim BS, Choi E, Shin SS.Ocular setariases of cattle were reported but those of equine hosts have never been reported in the Republic of Korea (Korea). We found motile worms in the aqueous humor of 15 horses (Equus spp.) from 12 localities in southern parts of Korea between January 2004 and November 2017. After the affected animals were properly restrained under sedation and local anesthesia, 10 ml disposable syringe with a 16-gauge needle was inserted into the anterior chamber of the affected eye to successfully remove the parasites. The male worm that was found in 7 of the cases showed a pair of lateral appendages n...
Go YY, Bailey E, Timoney PJ, Shuck KM, Balasuriya UB.We investigated the correlation between in vitro susceptibility of CD3(+) T lymphocytes to equine arteritis virus (EAV) infection and establishment of persistent infection among 14 stallions following natural infections. The data showed that carrier stallions with a CD3(+) T lymphocyte susceptibility phenotype to in vitro EAV infection may be at higher risk of becoming carriers than those that lack this phenotype (P = 0.0002).
Wentink GH.The movements of the right hind limb of horses with normal locomotion were studied using cinephotography and electromyography. A model of the cycle of a stride in the walk and the trot was constructed and the kinetic parameters of the segments of the limb were calculated. A good correlation was obtained between the kinetics and the periods of the cycle of a stride during which individual muscles display activity. The results of this study demonstrate that: at placing and lifting, i.e., when a change occurs in the direction of the movement of the limb; b) At the walk, the greatest forces operan...
Williams KJ, Robinson NE, Defeijter-Rupp H, Millerick-May M, Stack A, Hauptman J, Derksen FJ.Exercise-induced pulmonary hemorrhage (EIPH), which has been reported in humans and a variety of domestic animals following strenuous exercise, is most often documented in racehorses. Remodeling of pulmonary veins (VR) in equine EIPH was recently described, suggesting that it contributes to the pathogenesis of the disease. The cause of VR is unknown. We tested the hypothesis that the development of VR follows pulmonary blood flow distribution, preferentially occurring in the caudodorsal lung region. Furthermore, we hypothesized that VR underpins development of the other lesions of EIPH patholo...
Black WD, Wilcox RS, Stevenson RA, Hartley CA, Ficorilli NP, Gilkerson JR, Studdert MJ.The objective of this study was to determine the incidence of serum neutralising (SN) antibody to ERAV, ERBV1 and ERBV2 in a population of horses from birth to 22 years of age. The prevalences of ERAV, ERBV1 and ERBV2 SN antibodies in 381 sera obtained from 291 horses were 37%, 83% and 66%, respectively. ERAV, ERBV1 and ERBV2 maternal antibody was present in foals 12 h postsuckling but by 10-12 months, ERAV SN antibody was not detected in any of the horses, while ERBV1 and ERBV2 SN antibodies were common (83% and 100%, respectively). Sera were obtained from 44 Thoroughbred horses when they wer...
Hultgren BD.The congenital absence of myenteric ganglia in the terminal portion of the ileum, cecum, and entire colon of white foals with overo spotted parents was reported. Males as well as females were affected. The foals were generally normal at birth but did not defecate. Signs of colic were noticed between 5 and 24 hours after birth, with death occurring at 23 to 132 hours.
Lian WC, Liau MY, Mao CL.Nervous disorders were found in two horses and verified as aseptic encephalitis by necropsy in the summer of 2000. To investigate agents that affected the horses, diagnostic procedures involving virus isolation, neutralization test and reverse transcription-polymerase chain reaction (RT-PCR) were performed. We intracranially inoculated litters of suckling mice with tissues suspected of containing aseptic encephalitis, including cerebrum, cerebellum, brain stem, thalamus, and cerebrospinal fluids; the mice were then observed for 14 days. Neutralizing antibodies against Japanese encephalitis (JE...
Parkes RSV, Pfau T, Weller R, Witte TH.During racing, injury is more likely to occur on a bend than on a straight segment of track. This study aimed to quantify the effects of galloping at training speeds on large radius curves on stride parameters and limb lean angle in order to assess estimated consequences for limb loading. Seven Thoroughbred horses were equipped with a sacrum-mounted inertial measurement unit with an integrated GPS, two hoof-mounted accelerometers and retro-reflective markers on the forelimbs. Horses galloped 2-4 circuits anticlockwise around an oval track and were filmed at 120 frames per second using an array...
