Disease etiology in horses refers to the study of the causes and development of diseases within equine populations. It encompasses various factors, including genetic predisposition, environmental influences, infectious agents, and nutritional imbalances, that contribute to the onset and progression of diseases in horses. Understanding disease etiology is essential for identifying risk factors and implementing preventative measures in equine health management. This topic includes research on pathogen-host interactions, the impact of management practices on disease incidence, and the role of genetic and environmental factors in disease susceptibility. This page compiles peer-reviewed research studies and scholarly articles that explore the mechanisms, contributing factors, and implications of disease etiology in horses.
Finley MR, Li Y, Hua F, Lillich J, Mitchell KE, Ganta S, Gilmour RF, Freeman LC.In dogs and in humans, potassium channels formed by ether-a-go-go-related gene 1 protein ERG1 (KCNH2) and KCNQ1 alpha-subunits, in association with KCNE beta-subunits, play a role in normal repolarization and may contribute to abnormal repolarization associated with long QT syndrome (LQTS). The molecular basis of repolarization in horse heart is unknown, although horses exhibit common cardiac arrhythmias and may receive drugs that induce LQTS. In horse heart, we have used immunoblotting and immunostaining to demonstrate the expression of ERG1, KCNQ1, KCNE1, and KCNE3 proteins and RT-PCR to det...
Billich C, Sauder C, Frank R, Herzog S, Bechter K, Takahashi K, Peters H, Staeheli P, Schwemmle M.The recent observation that Borna disease virus (BDV)-reactive antibodies from psychiatric patients exhibit only low avidity for BDV antigen called into question their diagnostic value and raised the possibility that antigenically related microorganisms or self antigens caused the production of these antibodies. We further characterized the specificity of these antibodies. Methods: We established a peptide array-based screening test that allows the identification of antibodies directed against linear epitopes of the two major BDV proteins, the nucleoprotein (N) and the phosphoprotein (P). Resu...
Menzies-Gow NJ, Bond R, Patterson-Kane JC, McGowan CM.Two mature large-breed horses with coronary band dystrophy and chorioptic mange are described. They both had clinical signs of coronary band scaling and crusting but were not lame. Coronary band dystrophy can be differentiated from similar clinical conditions on the basis of the histological appearance of skin biopsy specimens, and by the exclusion of other possible disease processes. Its aetiology is uncertain, but probably involves a localised defect of keratinisation affecting the specialised epithelium of the coronary band.
Glaser AL, Renshaw RW, Trock SC, Brady RC, Dubovi EJ.Salem virus (SalV) is a recently identified equine virus belonging to the family Paramyxoviridae. The only known isolate was obtained from a horse that was involved in a disease outbreak of undetermined nature and the circumstances of its isolation suggested an etiologic role. However, the experimental infection of a colostrum-deprived foal failed to reproduce the disease; only mild neutropenia and temperature elevation were recorded. An additional attempt to establish an etiological relationship with the disease was made by conducting a retrospective evaluation of the serological profiles of ...
Berthoud H, Frey J, Kuhnert P.Actinobacillus equuli, a member of the family Pasteurellaceae is the etiologic agent of a frequently lethal septicemia in neonatal foals as well as other more chronic diseases like arthritis, pleuritis, pneumonia or peritonitis. It may also be isolated from the oral cavity of healthy horses. Hemolytic isolates of A. equuli are known but so far no virulence determinants have been described for this bacterial species. By screening hemolytic A. equuli strains with specific gene probes, a hemolysin, designated Aqx (A. equuli RTX (repeats in the structural toxin)) was identified. This hemolysin was...
Craigo JK, Leroux C, Howe L, Steckbeck JD, Cook SJ, Issel CJ, Montelaro RC.The genetic variation of equine infectious anaemia virus (EIAV) clearly affects the antigenic properties of the viral envelope; however, effects on immunogenicity remain undefined, although widely assumed. Here, the immunogenicity is reported of a novel, neutralization-resistant, pony-isolate envelope EIAV(PV564DeltaPND) that contains a 14-residue deletion in the designated principal neutralizing domain (PND) of the gp90 protein. Two ponies inoculated with a chimeric virus, EIAV(DeltaPND), containing the EIAV(PV564DeltaPND) envelope in a reference provirus strain, remained asymptomatic through...
Gray AW, Davies ME, Jeffcott LB.Cathepsin K and cathepsin B were immunolocalised in equine osteoclasts (OC s) present in ex vivo cartilage/subchondral bone samples. Samples were obtained post mortem from the lateral trochlear ridge (LTR) of six horses and ponies aged between 303 days gestation to 8 months. Strong expression of cathepsin K was detected in OC s, particularly those located at the osteochondral junction, apparently involved in the resorption of calcified cartilage. Cathepsin K expression was also detected in hypertrophic chondrocytes and in the endothelial cells of some blood vessels penetrating the hypertrophic...
Davis JL, Gardner SY, Schwabenton B, Breuhaus BA.To identify clinical signs, underlying cardiac conditions, echocardiographic findings, and prognosis for horses with congestive heart failure. Methods: Retrospective study. Methods: 14 horses. Methods: Signalment; history; clinical signs; clinicopathologic, echocardiographic, and radiographic findings; treatment; and outcome were determined by reviewing medical records. Results: All 14 horses were examined because of a heart murmur; tachycardia was identified in all 14. Twelve horses had echocardiographic evidence of enlargement of 1 or more chambers of the heart. Other common clinical finding...
McGowan CM, Posner RE, Christley RM.A questionnaire was used to determine the incidence of exertional rhabdomyolysis and the factors that might have contributed to its occurrence among 423 polo horses in 11 yards. The yards were selected at random, six of them with 111 horses, in north-eastern USA, and five with 312 horses in south-east England. During the 1999/2000 season the incidence of the condition was 7.3 per cent (9 per cent in the USA and 6.7 per cent in England). The incidence in mares was similar in the two countries, 8.4 per cent in the USA and 8.0 per cent in England, but the incidence in geldings in the USA (10 per ...
Widenhouse TV, Lester GD, Merritt AM.To determine the effect of pH with or without pepsin or taurocholic acid on the bioelectric properties of gastric squamous mucosa in horses. Methods: Gastric tissues obtained from 16 adult horses that did not have evidence of gastric disease. Methods: Bioelectric properties of squamous mucosa were determined, using modified Ussing chambers. Tissues then were exposed to mucosal pepsin (1 mg/ml) or taurocholic acid (2.5 mM) under neutral (pH 74) or acidic (pH 1.7) conditions. Results: Exposure of mucosal sheets to an acidic pH resulted in an immediate and sustained decrease in transmembrane pote...
Lord CC, Venter GJ, Mellor PS, Paweska JT, Woolhouse ME.African horse sickness (AHS) and equine encephalosis (EE) viruses are endemic to southern Africa. AHS virus causes severe epidemics when introduced to naive equine populations, resulting in severe restrictions on the movement of equines between AHS-positive and negative countries. Recent zoning of South Africa has created an AHS-free zone to facilitate equine movement, but the transmission dynamics of these viruses are not fully understood. Here, we present further analyses of serosurveys of donkeys in South Africa conducted in 1983-5 and in 1993-5. Age-prevalence data are used to derive estim...
Learmonth GS, Love DN, Wellington JE, Gilkerson JR, Whalley JM.The unusual mucin-like high molecular mass (Mr) glycoprotein 2 (gp2) has only been described in the equid alphaherpesviruses, among which there is considerable antigenic cross-reactivity. Equine herpesvirus 1 (EHV-1) gp2 is cleaved into a highly glycosylated N-terminal subunit and a 42 kDa C-terminal cleavage product. In order to investigate their antigenic recognition by horses naturally infected with EHV-1 and/or equine herpesvirus 4 (EHV-4), the C-terminal cleavage product and high Mr gp2 were affinity purified. Cross-reactivity between EHV-1 and EHV-4 was observed for the high Mr gp2 using...
Magnusson LE, Ekman S.Osteoarthrosis (OA) of the antebrachiocarpal joint from 7 riding horses is described. The horses were old mares and developed severe OA, with ankylosis in some of the joints. The lesions were bilateral, and the owners noticed the lameness in a late event. The cause of severe OA in these mares is not clear. The fact that OA was bilateral indicates that a single traumatic injury is unlikely as an etiologic factor. Considering the severe joint lesions it took long time before the horse-owners noticed the lameness. It is discussed if the threshold of pain is higher in the antebrachiocarpal joint c...
Butcher MT, Ashley-Ross MA.Fetlock joint kinematics during galloping in 2-, 3-, 4-, and 5-year-old Thoroughbreds in race training were quantified to determine if differences due to age could account for the observation that 2-year old Thoroughbred racehorses incur a high number of injuries to the bones and soft tissues in the distal forelimbs during training and at the outset of racing. Twelve Thoroughbred racehorses were videotaped in the sagittal plane at 250 frames/s during their daily galloping workout on a 7/8 mile sand-surface training track. Four galloping strides were recorded for each horse and subsequently dig...
Giguère S, Viel L, Lee E, MacKay RJ, Hernandez J, Franchini M.Work in humans and laboratory animals has identified a central role for cytokines and chemokines in development and persistence of lower airway inflammation. The objectives of this study were to determine interleukin (IL)-1 beta, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha induction in bronchoalveolar lavage (BAL) of control horses and horses with heaves both during remission and exacerbation of the disease, and to determine the effect of therapy with inhaled fluticasone propionate on the cytokine profile of horses with heaves. IL-1 beta an...
Iqbal J, Purewal AS, Edington N.The aim of this study was to investigate the role of immediate early gene (gene63) in the pathogenesis of equine herpesvirus 1 (EHV-1) acute and latent infections in equine and murine models. EHV-1 gene63 mutant virus (g63mut) along with EHV-1 (Ab4) was used for intracerebral and intranasal infection of 3 and 17-day-old mice. Both viruses were recovered at the same frequency from tissues after infection. Two Welsh ponies were infected via the intranasal route with each of the viruses. Acute infection was monitored by virus isolation from nasal swabs and peripheral blood leukocytes. Six weeks p...
Smith GW, Constable PD, Foreman JH, Eppley RM, Waggoner AL, Tumbleson ME, Haschek WM.To determine whether cardiovascular dysfunction is evident in horses with leukoencephalomalacia experimentally induced by administration of fumonisin B1. Methods: 11 healthy horses of various breeds (body weight, 252 to 367 kg). Methods: Horses were randomly assigned to 3 groups and administered fumonisin B1 daily. Horses received IV injections of 0 (control horses; n = 4), 0.01 (3), or 0.20 mg (4) of fumonisin B1/kg for 7 to 28 days. Horses were examined daily for evidence of neurologic disease. When neurologic signs consistent with leukoencephalomalacia were evident, horses were anesthetized...
Ehrenhofer MC, Deeg CA, Reese S, Liebich HG, Stangassinger M, Kaspers B.Investigations of the pathophysiology of ocular diseases require a detailed knowledge of the microanatomy of the eye. The available information is still inadequate for the equine retina despite the importance of eye diseases in equine medicine. Here we provide a comprehensive analysis of the histologic features of the horse eye as a reference for future studies. Thirty normal eyes of 15 healthy horses were examined immediately after slaughter. The retina of the horse differs considerably in the degree and quantity of neurons and glial elements as well as in vascular patterns compared to the re...
Takafuji VA, McIlwraith CW, Howard RD.To evaluate the effects of equine recombinant interleukin-1alpha (rEqIL-1alpha) and recombinant interleukin-1beta (rEqIL-1beta) on proteoglycan metabolism and prostaglandin E2 (PGE2) synthesis by equine articular chondrocytes in explant culture. Methods: Near full-thickness articular cartilage explants (approx 50 mg) harvested from stifle joints of a 3-year-old and a 5-year-old horse. Methods: Expression constructs containing cDNA sequences encoding EqIL-1alpha and EqIL-1beta were generated, prokaryotically expressed, and the recombinant protein purified. Near full-thickness articular cartilag...
Harrington DJ, Sutcliffe IC, Chanter N.Streptococcus equi is the aetiological agent of strangles, one of the most prevalent diseases of the horse. The animal suffering and economic burden associated with this disease necessitate effective treatment. Current antibiotic therapy is often ineffective and thus recent attention has focused on vaccine development. A systematic understanding of S. equi virulence, leading to the identification of targets to which protective immunity can be directed, is a prerequisite of the development of such a vaccine. Here, the virulence factors of S. equi are reviewed.
Patel A.This report describes a case of Rhodococcus equi infection causing pyogranulomatous skin disease and cellulitis in a two-year-old female domestic shorthaired cat. The case differed from previously reported cases in cats in its clinical presentation and in the locations of the lesions, which were similar to those seen in horses. The presence of an intracellular organism was confirmed by cytology and on histopathology. The aetiological diagnosis was confirmed by routine biochemical tests specific for R. equi on a pure isolate obtained from a biopsy specimen. The report also reviews the literatur...
Kaaden OR, Eichhorn W, Essbauer S.There is continual variation in viral epidemics regarding clinical symptoms, duration and disappearance, and the emergence of new diseases. This can be observed in both human and animal diseases. This evolution of virus diseases is mainly related to three factors: aetiological agent, host and environment. As far as genetic alterations of the virus are concerned, two major mechanisms are involved: mutations such as recombination and reassortment; and selection for resistance or susceptibility. This review focuses on the epidemiology of newly emerged virus diseases in man and animals, such as ac...
Kidd JA, Dyson SJ, Barr AR.Intratendonous infection in the absence of any clinical evidence of a wound has not, to our knowledge, been described previously in horses. This paper reports the clinical features, diagnostic techniques. treatment and outcome in 5 cases of septic flexor tendon core lesions. This condition is characterised by seven lameness and ultrasonographic evidence of a central intratendonous anechoic core lesion which may enlarge rapidly.
Murray MJ, Grady TC.This study examined whether a product containing a pectinlecithin complex (Pronutrin) (1) could prevent gastric lesions induced in the equine gastric squamous epithelial mucosa using a protocol of intermittent feed deprivation that resulted in prolonged increased gastric acidity (Murray and Eichorn 1996). Eight ponies were used and served as their own controls in 2 trials in which there were 72 h cumulative deprivation (alternating 24 h with no feed, then 24 h free choice hay), with a 4-week interval between trials. Ponies were assigned randomly to receive either 250 g Pronutrin plus 200 g pel...
Gibbons DF.Salmonellosis in Equidae occurs sporadically throughout the world; the incidence recorded ranges from less than 1 per cent to as much as 27 per cent. In 1976 there was a significant increase in disease and mortality caused by salmonellosis in horses in Britain and treatment was less successful than with other species. Data revealed a general progressive shift away from species specific salmonella serotypes towards the ubiquitous but less discerning strains of Salmonella typhimurium. The role of predisposing causes is assessed and treatment, prevention and zoonitic importance commented upon.
Barton AJ, Prow NA, Hall RA, Kidd L, Bielefeldt-Ohmann H.This report summarises the findings from a case of naturally-occurring Murray Valley encephalitis in a 2-year-old filly presenting with acute onset of depression and weakness. Serum samples tested at the onset of clinical signs were negative for Hendra and Kunjin virus antibodies, but positive for Murray Valley encephalitis virus (MVEV) using IgM-capture ELISA (1 : 300 dilution). A virus neutralisation assay performed 4 weeks later confirmed a titre of 1 : 160. Sera collected in the weeks preceding neurological signs returned a negative titre for MVEV 2 weeks prior followed by a titre ...
Katwa LC, Johnson PJ, Ganjam VK, Kreeger JM, Messer NT.Biosynthesis of endothelin-1 (ET-1), the most potent endogenous vasoconstrictor yet identified, is increased following myocardial infarction (MI) in man. Pathological events which occur in the connective tissues of the equine hoof during laminitis are similar in some respects, to changes occurring in the myocardial connective tissues following MI in man. The objective of this study was to determine whether ET-1 expression in connective tissues obtained from the hoof of laminitic horses is increased compared with tissues obtained from healthy horses. Expression of ET-1 in connective tissues of ...
Kalsow CM, Dwyer AE, Smith AW, Nifong TP.There is no direct verification of pineal gland involvement in human uveitis. Specimens of pineal tissue are not available during active uveitis in human patients. Naturally occurring uveitis in horses gives us an opportunity to examine tissues during active ocular inflammation. We examined the pineal gland of a horse that was killed because it had become blind during an episode of uveitis. The clinical history and histopathology of the eyes were consistent with post-leptospiral equine recurrent uveitis. The pineal gland of this horse had significant inflammatory infiltration consisting mainly...
Gabal MA, Awad YL, Morcos MB, Barakat AM, Malik G.Mycotoxicoses involving horses, rabbits and cattle have been studied. Fusarium tricinctum and T-2 toxin were isolated from all incriminated feedstuffs. Other isolated trichothecenes from the feed included HT-2, verrucarins and roridin. The toxins were separated, identified and quantitated using thin-layer chromatography, gas-liquid chromatography and mass spectrometry. T-2 toxin was detected in amounts varying from 0.5-204 ppm. The contaminated feedstuffs in connection with the affected horses and rabbits, included cereal grains (corn, cornstalks, bran and barley), whereas fescue hay was assoc...
Ricard RM, St-Jean G, Duizer G, Atwal H, Wobeser BK.The purpose of this study was to identify the most common causes of equine abortion in Canada, and to compare findings to similar reports from other countries. Equine. Necropsy reports from 901 equine abortion cases were acquired from provincial veterinary diagnostic laboratories across Canada. The final diagnosis was classified into basic abortion causes (infectious, non-infectious, unknown) and into primary and secondary categories for analysis. Non-infectious causes of abortion were the most frequently identified in Canada, with fetoplacental causes, including umbilical cord torsion or plac...
Miller R, Pott B.A case of subcutaneous phycomycosis of a horse from which Basidiobolus haptosporu was isolated is described. Although some clinical signs were similar to the disease caused by Hyphomyces destruens, the gross and microscopic pathology were different in several respects. Main characteristics of the histopathology were the narrow eosinophilic sleeve around wide, frequently septate hyphae scattered throughout the affected tissue and found commonly at the advancing border of the lesion. A retrospective study of 63 cases of phycomycosis diagnosed at this laboratory since 1970 indicated a further 11 ...
Begg AP, Carrick J, Chicken C, Blishen A, Todhunter K, Eamens K, Jenkins C.This report describes the fetoplacental pathology of associated abortion, premature birth, and neonatal loss in 46 of 442 equine abortion investigations between 2015 and 2019. Seven abortions, 26 premature births, and 13 neonatal deaths with positive polymerase chain reaction (PCR) were evaluated. In 83% of cases (38/46), infection was considered as the primary cause of loss based on quantitative PCR (qPCR) confirmation, pathological findings, and exclusion of other causes, and was supported by immunolabeling in fetoplacental lesions. Lymphohistiocytic placentitis with vasculitis (36/38) af...
Naylor JM, Nickel DD, Trimino G, Card C, Lightfoot K, Adams G.Historical, clinical and experimental data were collected from 9 horses homozygous for HYPP (H/H). All showed episodes of respiratory stertor, described as a rattling or honking sound, usually within the first week post partum. Five horses had one or more episodes of dysphagia, in 3 horses this was accompanied by drooling and in 3 by weight loss. In comparison, only one of 35 contemporaneous half siblings (of which approximately half would be expected to be of the H/N genotype and half N/N) was observed to have respiratory stertor prior to weaning and none had problems with dysphagia. One matu...
Smith P, Samuelson D, Brooks D.The anterior vasculature of the pony eye was examined by the corrosion cast method. The anterior segment of the pony eye has a vascular pattern which is similar but distinct from that of other mammalian species. Large iridal veins collateralized directly with the anterior vortex venous system. The intrascleral plexus was present but formed a fine, radially oriented, extensive network. This contrasted to the circumferential larger-diameter intrascleral plexus noted in dogs and the canal of Schlemm present in primates. The intrascleral plexus only drained posteriorly in the pony as compared to t...
Ackerman N, Garner HE, Coffman JR, Clement JW.The angiographic appearance of the normal equine foot was compared with the appearance of equine feet affected with chronic laminitis. The normal foot was characterized by complete filling of the terminal arch, 8 to 10 main branches between 0.1 and 0.2 cm in diameter, a symmetrical netlike vascular pattern in the corium of the hoof, and numerous fine vessels in the corium of the coronary band. The feet affected with chronic laminitis were characterized by poor filling of the terminal arch, larger and less numerous primary branches, an irregular vascular pattern in the corium of the hoof, areas...
Gao X, Jiang CG, Wang XF, Lin YZ, Ma J, Han XE, Zhao LP, Shen RX, Xiang WH, Zhou JH.The contribution of S2 accessory gene of equine infectious anemia virus (EIAV) to the virulence of pathogenic strains was investigated in the present study by reverse mutation of all four consensus S2 mutation sites in an attenuated EIAV proviral strain, FDDV3-8, to the corresponding sequences of a highly pathogenic strain DV117. The S2 reverse-mutated recombinant strain FDDVS2r1-2-3-4 replicated with similar kinetics to FDDV3-8 in cultivated target cells. In contrast to the results of other studies of EIAV with dysfunctional S2, reverse mutation of S2 only transiently and moderately increased...
Weese JS, Yu AA.Bacterial, dermatophilosis, and superficial ringworm infections are common skin diseases noted in equine dermatology. The ability to recognize and accurately diagnose the skin condition is key to selecting an appropriate and successful treatment regimen. Addressing underlying etiology, environmental management, and infection control play a crucial role in preventing relapse of clinical signs.
Draper AC, Bender JB, Firshman AM, Baird JD, Reed S, Mayhew IG, Valberg SJ.Investigating the epidemiology of shivering in horses. Objective: The purpose of this study was to characterise the signalment, clinical signs and management factors associated with shivering (also known as shivers), a relatively rare, poorly defined movement disorder in horses. Methods: Web-based case series survey and case-control study. Methods: A Web-based survey was used to obtain information from owners, worldwide, who suspected that their horse had shivering. Survey respondents were asked to answer standardised questions and to provide a video of the horse. Authors reviewed the surveys ...
Huggins L, Norris J, Conley A, Dini P.Abnormal or undesired mare behaviours are often assumed to be associated with ovarian abnormalities. Objective: We aimed to determine the incidence of abnormal behaviours and their association with concentrations of one or more ovarian hormones associated with a granulosa cell tumour (GCT). Methods: Retrospective descriptive. Methods: A total of 2914 hormonal profile samples submitted with the words behave, behaviour, or behaving in the submission history were analysed. The association between reported abnormal behaviours and concentrations of testosterone, anti-Müllerian hormone (AMH), inhib...
Fontaine P, Blond L, Alexander K, Beauchamp G, Richard H, Laverty S.Osteochondrosis dissecans (OCD) is a focal failure of endochondral ossification of the epiphysis characterized by the presence of cartilage flaps and osteochondral fragments. The objective of this study was to image epiphyseal development in the equine pelvic limb to determine whether there was a variation in site maturation that could be a predisposing factor for OCD. Pelvic limbs (fetuses and foals) were studied post-mortem. The epiphyses of the distal femur, tibia and talus were scanned with computed tomography (CT) and 1.5T magnetic resonance imaging (MRI) to investigate the degree and pat...
Lyons ET, Tolliver SC, Drudge JH, Stamper S, Swerczek TW, Granstrom DE.Several compounds (n = 13 single or combinations; most at therapeutic dosages) were evaluated between 1977 and 1992 in critical tests (n = 91) against benzimidazole (BZ) resistant small strongyles (Population S) and several other species of internal parasites in Shetland ponies, mostly under 1 year old. The closed breeding herd, from which the test ponies were selected, had been treated every 8 weeks with cambendazole (CBZ) for 4 years (1974-1978) and oxibendazole (OBZ) for 14 years (1978-1992). Published field test data (1974-1992) on older ponies in the herd showed BZ resistance of small str...
Equine infectious anaemia (EIA) is a disease with an almost worldwide distribution, with several outbreaks having been reported recently in European countries. In Italy, two regions, Lazio and Abruzzo, are considered as endemic areas for this disease. In nature, the EIA virus is mechanically transmitted by biting flies such as tabanids (Diptera: Tabanidae), although few studies have investigated the epidemiological implications. In the present study, several sites characterized by different levels of EIA prevalence were sampled. In sites with high tabanid populations, a seasonal succession of ...
Stange LM, Krieter J, Czycholl I.Equine headshaking syndrome (EHS) is characterised as non-physical and involuntary movement of the horse's head and neck. Although EHS is clinically simple to diagnose, its aetiopathogenesis often remains unclear. The aim of this study was to gain an overview of signalment and therapy possibilities used in France and Switzerland. To do this, an online survey was developed and distributed via newsletters. A total of 933 complete, answered surveys from France ( = 804) and Switzerland ( = 129) were evaluated. The median age in France was 12.4 years (CH = 14.3). Mostly geldings were affected (58.5...
Horin P, Osickova J, Necesankova M, Matiasovic J, Musilova P, Kubickova S, Hubertova D, Vyskocil M, Rubes J.In previous work, we found significant associations of horse chromosome 15 (ECA15) microsatellite markers HMSO1 and HTG06 with two horse infections, Rhodococcus equi and Lawsonia intracellularis, respectively. Interleukin-1 beta subunit and interleukin-1 receptor antagonist encoding genes (IL1B and IL1RN) could be considered as candidate genes underlying the associations reported. Therefore, we identified single nucleotide polymorphisms (SNPs) within three interleukin-1 beta functionally related genes: IL1B, IL1RN and Casp1 (interleukin-1 beta converting enzyme/caspasel encoding gene). Using a...
Khrustaleva TA, Khrustalev VV, Barkovsky EV, Kolodkina VL, Astapov AA.The SF23 peptide corresponding to the receptor binding fragment of diphtheria toxin (residues 508-530) has been synthesized. This fragment forming a protruding beta hairpin has been chosen because it is the less mutable B-cell epitope. Affine chromatography and ELISA show that antibodies from the sera of persons infected by toxigenic Corynebacterium diphtheriae and those immunized by diphtheria toxoid are able to bind the synthetic SF23 peptide. There are antibodies recognizing the SF23 peptide in the serum of horses hyperimmunized with diphtheria toxoid. Analysis of circular dichroism spectra...
Knowles EJ, Withers JM, Mair TS.The use of plasma fructosamine concentration ([fructosamine]) as a marker of abnormal glucose homeostasis in laminitic horses has not been investigated. Objective: Plasma fructosamine concentration may be higher amongst laminitic horses than normal horses; this might relate to underlying insulin resistance. Objective: 1) To compare [fructosamine] between laminitic and normal horses. 2) To investigate associations between [fructosamine] at presentation in laminitic horses with a) single sample markers of insulin resistance and b) outcome. Methods: Plasma fructosamine concentration, fasting seru...
Manohar M.Right atrial, right ventricular, and pulmonary artery pressures, along with change in pleural pressure, were determined with catheter-tipped micromanometers in two groups of ponies at rest, as well as during moderate (trot; heart rate = 180 beats . min-1) and severe (gallop; heart rate = 220 beats . min-1) exercise performed on a treadmill. Group A (n = 8) ponies served as controls, and group B ponies (n = 6) had laryngeal hemiplegia (LH) induced by sectioning the left recurrent laryngeal nerve 20-29 days before the study. It was observed that LH ponies could not gallop for more than 45-90 s. ...
El-Assaad I, Di Bari JA, Yasuda K, Divers TJ, Summers BA, de Lahunta A, Mohammed H.Equine motor neuron disease (EMND) is a neurodegenerative disorder of unknown etiology affecting horses worldwide. Trans-Active Response DNA Binding Protein of 43 kDa (TDP-43) has been reported in the central nervous system (CNS) of several neurodegenerative conditions in humans including Amyotrophic Lateral Sclerosis (ALS) and assumed to play role in the disease. We examined whether horses afflicted with EMND express the TDP-43 in CNS. Ten horses with EMND and 6 controls of different ages and breed we enrolled. Detection of presence of TDP-43 protein in the CNS was analyzed by immunohistoche...
Slocombe RF, Huntington PJ, Friend SC, Jeffcott LB, Luff AR, Finkelstein DK.Nine horses with clinical signs of Australian Stringhalt were killed and tissues collected for a detailed pathological study. Lesions were limited to peripheral nerves and muscles. The most severely affected nerves were the superficial and deep peroneal, distal tibial, plantar digital, volar and recurrent laryngeal nerve with changes characterised by a selective loss of large diameter myelinated fibres with various degrees of demyelination, fibrosis, Schwann cell proliferation and onion-bulb formation. A routine evaluation of the brain and spinal cord by light microscopy failed to reveal any c...
Maxwell MH.A series of experiments is described in which attempts were made to produce an avian eosinophilia using various agents. Although none of the experiments was decisive, two demonstrated a slight rise in the eosinophil counts. In one experiment horse serum was injected into a group of fowls on alternate days for 42 days. No eosinophils were seen in any blood smears after this treatment. After a rest period of eight days the birds received further injections for 10 days. The mean eosinophil count rose to over 4 per cent with a range of 1 to 11 per cent. It is considered that this type of response ...
Hensel M, Meason-Smith C, Plumlee QD, Myers AN, Coleman MC, Lawhon S, Rodrigues Hoffmann A, Rech RR.Pulmonary mycosis secondary to enterocolitis is an uncommon diagnosis in equine medicine, but is thought to result from mucosal compromise and translocation of enteric fungi. The aetiological agent associated with translocation is often identified based on fungal culture or hyphal features in histological sections. In order to understand better the aetiological agents involved, six horses diagnosed with Salmonella enteritis and concurrent pulmonary mycosis were identified retrospectively through a database search of veterinary teaching hospital records. Samples from these cases were subjected ...
de Laat MA, van Haeften JJ, Sillence MN.Managing equine hyperinsulinemia is crucial for preventing laminitis, but our understanding of the mechanisms involved in insulin dysregulation in this species is incomplete. C-peptide is co-secreted with insulin but is resistant to hepatic metabolism and can be used to study insulin dysregulation. This study examined C-peptide secretion in serial blood samples collected after oral and i.v. dextrose (0.75 g/kg) administration to 9 ponies (BCS, 7.1 ± 0.5). The ponies were designated as hyperinsulinemic (HI) or normoinsulinemic (NI) responders before the study, using oral glucose tests and fast...
Kelly G, Lumsden JM, Dunkerly G, Williams T, Hutchins DR.Mucosal ulcers and, occasionally, small granulomas on the axial surface of one or both arytenoid cartilages have been found in TB yearlings presented for post sale endoscopic examination. Objective: To determine the incidence, endoscopic characteristics and outcome of a group of Thoroughbred yearlings affected with mucosal ulcers and granulomas of the arytenoid cartilage. Objective: The incidence of mucosal ulceration of the arytenoid cartilages of yearling Thoroughbreds is relatively high compared to other upper airway abnormalities; and that the majority of mucosal ulcers heal uneventfully, ...
Ohnesorge B, Deegen E, Miesner K, Geldermann H.Laryngoscopic examination during sedation was performed on 24 stallions and on their offspring (240 foals and 474 adult horses). Additionally the dams (n = 308) of 35 foals and 216 horses were examined. With the bilateral comparison of the arytaenoid movements the function of the abductory and adductory laryngeal muscles were evaluated and the left abductory dysfunction (idiopathic laryngeal hemiplegia, ILH) was divided into six degrees. The incidence and degree of ILH depended on age and the occurrence of the same dysfunction in the parents. Foals suffered in significantly lower number (24.7 ...