Disease diagnosis in horses involves the identification and characterization of illnesses through various diagnostic methods and tools. This process is essential for effective veterinary care and management of equine health. Techniques used in diagnosing diseases in horses include clinical examinations, laboratory tests, imaging modalities such as ultrasonography and radiography, and molecular diagnostics. Blood tests are frequently utilized to assess parameters such as complete blood count and biochemical profiles, which can indicate underlying health issues. Additionally, advancements in genetic testing and biomarker identification have enhanced the ability to detect specific diseases early. This page aggregates peer-reviewed research studies and scholarly articles that explore diagnostic methodologies, their applications, and their impact on equine health management.
Lotstra RJ, van den Broek J, Power T, Marr CM, Wijnberg ID.Atrial fibrillation is a common equine arrhythmia. Quinidine alone, or with digoxin are common treatments. Studies on outcome in Warmblood populations in which duration of the AF is often unknown are limited. Objective: To identify the factors that are associated with the success of full treatment cardioversion with oral medication, and establish whether there are differences in these factors between institutions. Methods: Retrospective case series using patient records of Equine University Clinic of Utrecht University and Rossdales Equine Hospital, Newmarket. Methods: Forty-nine horses treate...
Lotstra RJ, van den Broek J, Power T, Marr CM, Wijnberg ID.Atrial fibrillation is a common equine arrhythmia. Quinidine alone, or with digoxin are common treatments. Studies on outcome in Warmblood populations in which duration of the AF is often unknown are limited. Objective: To identify the factors that are associated with the success of full treatment cardioversion with oral medication, and establish whether there are differences in these factors between institutions. Methods: Retrospective case series using patient records of Equine University Clinic of Utrecht University and Rossdales Equine Hospital, Newmarket. Methods: Forty-nine horses treate...
Froydenlund TJ, Dixon PM, Smith SH, Reardon RJ.The morphology of the dorsal (DCB) and ventral (VCB) nasal conchal bullae, including their cellulae, drainage and histology, are poorly described. The recent recognition that these bullae can become infected, causing chronic unilateral nasal discharge has stimulated interest in these structures. A more complete understanding of their anatomy would be useful in the diagnosis and treatment of their disorders. Objective: To document the structure, drainage and histology of the equine DCB and VCB. Methods: Descriptive. Methods: Fourteen fresh cadaveric horse heads, were transected sagittally midli...
van Loon G, Lefère L, Bauwens C, Kleyn K, Broux B, De Clercq D, Deprez P.Yellow fat disease or steatitis is characterised by a local or general inflammation of fat tissue and is occasionally found in horses. Diagnosis is challenging because of the wide range of nonspecific clinical signs. Objective: To describe clinical signs, treatment, outcome and ultrasonographic findings in horses with steatitis. Methods: Retrospective study (January 2008 to January 2015). Methods: History, clinical signs, ultrasonographic findings, diagnosis, treatment and outcome were recorded. Results: Twenty cases (18 horses, 2 donkeys; 9 mares, 9 stallions, 2 geldings) were retrieved from ...
Allen JL, Herbert G, Muscatello G, Gilkerson JR.Bronchopneumonia caused by Rhodococcus equi is an important disease of young horses throughout the world. Although early diagnosis and treatment improves the prognosis, this also increases the amount of antimicrobial usage and therefore increases the likelihood of resistance developing. Objective: The aim of this study was to determine the level of resistance to commonly prescribed antimicrobial agents of 97 virulent Rhodococcus equi isolates. Methods: Analysis of archived samples. Methods: Virulent Rhodococcus equi isolates were collected between 1991 and 2014 from clinically affected horses ...
Bochnia M, Ziegler J, Sander J, Uhlig A, Schaefer S, Vollstedt S, Glatter M, Abel S, Recknagel S, Schusser GF, Wensch-Dorendorf M, Zeyner A.Hypoglycin A (HGA) in seeds of Acer spp. is suspected to cause seasonal pasture myopathy in North America and equine atypical myopathy (AM) in Europe, fatal diseases in horses on pasture. In previous studies, this suspicion was substantiated by the correlation of seed HGA content with the concentrations of toxic metabolites in urine and serum (MCPA-conjugates) of affected horses. However, seed sampling was conducted after rather than during an outbreak of the disease. The aim of this study was to further confirm the causality between HGA occurrence and disease outbreak by seed sampling during ...
Hammersley E, Duz M, Marshall JF.Triamcinolone is commonly used in equine practice for the treatment of orthopaedic conditions. A serious potential adverse effect of triamcinolone is laminitis. However, evidence for the risk of laminitis associated with triamcinolone use is limited. Objective: To determine the risk of laminitis within 90 days of triamcinolone administration and compare with the risk of laminitis in a veterinary-attended horse population. Methods: Retrospective study of clinical records. Methods: Text mining and data extraction was performed using content analysis software (SimStat-WordStat v.6) on a database ...
Bardell DA, Archer DC, Milner PI.Colic remains a life-threatening condition in the horse. Ischaemia and reperfusion following correction of small intestinal strangulation may produce oxidative stress. The ability to withstand oxidative stress depends on antioxidant levels and may be linked to horse survival. Objective: To measure peripheral antioxidant levels in horses undergoing exploratory laparotomy with small intestinal strangulation. Methods: Case-control study. Methods: Blood and plasma were collected from horses undergoing exploratory laparotomy for small intestinal strangulation and stored at -80°C. Controls involved...
Abdelgawad A, Hermes R, Damiani A, Lamglait B, Czirják GÁ, East M, Aschenborn O, Wenker C, Kasem S, Osterrieder N, Greenwood AD.Equine herpesvirus type 1 (EHV-1) causes respiratory disorders and abortion in equids while EHV-1 regularly causes equine herpesvirus myeloencephalopathy (EHM), a stroke-like syndrome following endothelial cell infection in horses. Both EHV-1 and EHV-9 infections of non-definitive hosts often result in neuronal infection and high case fatality rates. Hence, EHV-1 and EHV-9 are somewhat unusual herpesviruses and lack strict host specificity, and the true extent of their host ranges have remained unclear. In order to determine the seroprevalence of EHV-1 and EHV-9, a sensitive and specific pepti...
Delesalle CJ, Callens C, Van Colen I, Lefebvre RA.Selective 5-HT4 receptor agonists such as prucalopride are used as human prokinetics, since activation of 5-HT4 receptors on intestinal cholinergic neurons facilitates acetylcholine release. 5-HT4 receptors, linked to adenylyl cyclase, act via generation of cAMP. None of the 4 in vitro studies on 5-HT in horses provided evidence for neuronal 5-HT4 receptors, but none used the protocol as described in human studies [1-4]. Objective: To investigate whether functional 5-HT4 receptors are present in the equine small intestine. Methods: In vitro organ bath set up, applying electrical field stimulat...
Anastasi E, Giguère S, Berghaus LJ, Hondalus MK, Willingham-Lane JM, MacArthur I, Cohen ND, Roberts MC, Vazquez-Boland JA.The objective of this study was to identify the molecular mechanism of macrolide resistance in the actinomycete Rhodococcus equi, a major equine pathogen and zoonotic agent causing opportunistic infections in people. Methods: Macrolide-resistant (n = 62) and macrolide-susceptible (n = 62) clinical isolates of R. equi from foals in the USA were studied. WGS of 18 macrolide-resistant and 6 macrolide-susceptible R. equi was performed. Representative sequences of all known macrolide resistance genes identified to date were used to search the genome assemblies for putative homologues. PCR w...
Pedersen PJ, Thomsen KB, Olander ER, Hauser F, Tejada Mde L, Poulsen KL, Grubb S, Buhl R, Calloe K, Klaerke DA.The KCNH2 and KCNE2 genes encode the cardiac voltage-gated K+ channel KV11.1 and its auxiliary β subunit KCNE2. KV11.1 is critical for repolarization of the cardiac action potential. In humans, mutations or drug therapy affecting the KV11.1 channel are associated with prolongation of the QT intervals on the ECG and increased risk of ventricular tachyarrhythmia and sudden cardiac death--conditions known as congenital or acquired Long QT syndrome (LQTS), respectively. In horses, sudden, unexplained deaths are a well-known problem. We sequenced the cDNA of the KCNH2 and KCNE2 genes using RACE an...
Williams DC, Aleman MR, Brosnan RJ, Fletcher DJ, Holliday TA, Tharp B, Kass PH, Steffey EP, LeCouteur RA.Previous study of the diagnostic validity of electroencephalography (EEG) to detect abnormalities in equine cerebral cortical function relied on the administration of various drugs for sedation, induction, and maintenance of general anesthesia but used identical criteria to interpret recordings. Objective: To determine the effects of 2 inhalation anesthetics on the EEG of healthy horses. Methods: Six healthy horses. Methods: Prospective study. After the sole administration of one of either isoflurane or halothane at 1.2, 1.4, and 1.6 times the minimum alveolar concentration, EEG was recorded d...
Rodriguez C, Taminiau B, Brévers B, Avesani V, Van Broeck J, Leroux A, Gallot M, Bruwier A, Amory H, Delmée M, Daube G.The equine faecal microbiota is very complex and remains largely unknown, while interspecies interactions have an important contribution to animal health. Clostridium difficile has been identified as an important cause of diarrhoea in horses. This study provides further information on the nature of the bacterial communities present in horses developing an episode of diarrhoea. The prevalence of C. difficile in hospitalised horses at the time of admission is also reported. Results: Bacterial diversity of the gut microbiota in diarrhoea is lower than that in non-diarrhoeic horses in terms of spe...
Rashmir-Raven A, Lavagnino M, Sedlak A, Gardner K, Arnoczky S.Hereditary equine regional dermal asthenia (HERDA) is a genetic disorder of collagen resulting in fragile, hyper-extensible skin and ulcerative lesions. The predominance of skin lesions have been shown to occur on the dorsum of HERDA-affected horses. While this has been postulated to be due to increased exposure to sunlight of these areas, the precise pathological mechanism which causes this to occur is unclear. Objective: We hypothesized that an increase in collagenase activity, that has been associated with the exposure of dermal fibroblasts to sunlight, will significantly degrade the materi...
Trachsel DS, Grenacher B, Schwarzwald CC.Plasma atrial/A-type natriuretic peptide concentration (CpANP) was measured in horses presenting with various heart diseases to assess its potential diagnostic value. Methods: Fifteen healthy horses (Group 1) and 60 horses with various heart diseases associated with normal chamber size and function (Group 2, n = 24), associated with abnormal left atrial (LA) size and/or function but normal left ventricle (LV) (Group 3, n = 19), or associated with both abnormal LA and LV size and/or function (Group 4, n = 17). Methods: CpANP was measured by a commercially available radioimmunoassay. Echoc...
Scharner D, Bankert J, Brehm W.The examination of patients suffering from an acute abdomen routinely comprises both clinical and rectal examinations, and is ever more frequently accompanied by an ultrasonographic abdominal examination. The aim of the study was to compare the findings as defined through rectal examination with the results of the ultrasonographic examination for different forms of colic. Methods: In a retrospective study, the patient records of the Large Animal Clinic of the University of Leipzig from 2012 and 2013 were analysed, and those of horses suffering from colic were included. Diagnoses made through r...
Velineni S, DeNegri R, Artiushin SC, Timoney JF.Streptococcus zooepidemicus (Sz) and its clonal derivative Streptococcus equi (Se) share greater than 96% DNA identity and elicit immune responses to many shared proteins. Identification of proteins uniquely targeted by the immune response to each infection would have diagnostic value. Objective: The aim of the study was to compare serum antibody responses of horses infected by Se or Sz. Methods: Antibody levels were measured to panels of recombinant proteins of Sz and Se in sera of horses and ponies before and after experimental and naturally occurring invasive infections by these organisms. ...
Donoghue EM, Lyons ET, Bellaw JL, Nielsen MK.Parascaris spp. infects foals worldwide and may cause airway inflammation in addition to small intestinal impaction and rupture. It is observed that acquired immunity eliminates ascarid burdens beginning at about 6 months of age, and current evidence suggests that a single parasite generation propagates in each foal crop. The purpose of this study was to monitor natural parasitic infections in untreated mixed breed horse foals over the course of 0-300 days of age. Fecal samples were collected monthly from all foals born in 2014 (n=13), beginning July 2014 through February 2015. Fecal egg count...
Schnobrich MR, Turner RO, Belcher CN, Slack J.Transrectal ultrasound of the internal urogenital tract may be used to aid in the diagnosis of reproductive tract and urinary tract pathology in both stallions and geldings. Abnormalities of the accessory sex glands of geldings are uncommon, although prostatic masses have recently been described in adult geldings presenting with dysuria, stranguria, and/or hematuria. The purpose of this study was to describe the normal ultrasonographic features and sizes of the accessory sex glands, caudal ureters, and pelvic urethra in clinically normal geldings. Eleven healthy geldings with no history of uro...
Hamond C, Martins G, Bremont S, Medeiros MA, Bourhy P, Lilenbaum W.A strain of Leptospira kirschneri (serogroup Grippotyphosa) was cultured from urine of a mare post-abortion in Brazil and characterized by serogrouping, multiple-locus variable-number tandem repeat analysis, PGFE, and sequencing of genes rrs and secY. Strains of L. kirschneri have apparently never been recovered from horses in tropical area, only in Europe and USA. Knowledge of local epidemiology is important to interpret genetic profiles of leptospires circulating in an area.
Mariella J, Isani G, Andreani G, Freccero F, Carpenè E, Castagnetti C.Abnormalities in total Mg (tMg) concentration in plasma and/or serum are common in critically ill humans, and the association with increased mortality has been documented in several clinical studies in adults and newborns with hypoxic-ischemic encephalopathy. Abnormalities in tMg were studied in hospitalized dogs, cats, and adult horses. Newborn foals were scarcely studied with regard to Mg concentration. The aims of the present study were: (1) to compare two analytical methods for the determination of tMg in plasma: the automated colorimetric method and the atomic absorption spectrometry; (2)...
Mini-myoglobin (mini-HHMb) is a fragment of horse-heart myoglobin (HHMb) considered to be the prototype of the product encoded by the central exon of the HHMb gene. For this reason, mini-HHMb has been studied extensively showing that carbonylation and oxygenation properties of the ferrous form are similar to those of the full-length protein, while kinetics and thermodynamics of azide binding to the ferric form are significantly different from those of HHMb. To analyze the structure-function relationships in mini-HHMb and the role of conformational fluctuations in ligand accessibility, the mole...
Bockisch F, Aboling S, Coenen M, Vervuert I.Vitamin-D intoxication by yellow oat grass is often reported under the syndrome of enzootic calcinosis in ruminants in the upper regions of the Alps. The intake of Trisetum flavescens in ruminants and horses induces calcification of soft tissue, including vessels, tendons and ligaments, lung, heart and kidneys. Clinical symptoms, including a reluctance to move, inappetence, body-weight loss and impaired organ function, are frequently observed. To date, there are only a very few case reports about yellow-oat-grass intoxication in horses. The present case report describes Vitamin-D intoxication ...
Sokół R, Michalski MM.The presence of Hippobosca equina strongly influences the behaviour and health status of horses. The aim of the study was to analyse the invasion dynamics of the forest fly in Polish primitive horses (Equus caballus gmelini) in the Popielno Forest Reserve (northeastern Poland). Observations were carried out from May to September, every two weeks for two consecutive years (2012 and 2013) in five study groups: in 11-12-year-old mares with foals, 6-7-year-old leading stallions, 1.5-year-old fillies, 1.5-year-old colts and 9-10-year-old working geldings. Adult H. equina were counted in the preferr...
Bullone M, Beauchamp G, Godbout M, Martin JG, Lavoie JP.Endobronchial ultrasonography (EBUS) revealed differences in the thickness of the layer representing subepithelial tissues (L2) between human asthmatics and controls, but whether this measurement correlates with airway smooth muscle (ASM) remodeling in asthma is unknown. In this study, we sought to determine the ability of EBUS to predict histological ASM remodeling in normal and equine asthmatic airways. We studied 109 isolated bronchi from the lungs of 13 horses. They underwent EBUS examination using a 30 MHz radial probe before being processed for histology. ASM remodeling parameters were e...
Mirams M, Ayodele BA, Tatarczuch L, Henson FM, Pagel CN, Mackie EJ.During the early stages of articular osteochondrosis, cartilage is retained in subchondral bone, but the pathophysiology of this condition of growing humans and domestic animals is poorly understood. A subtractive hybridization study was undertaken to compare gene expression between the cartilage of early experimentally induced equine osteochondrosis lesions and control cartilage. Of the many putative differentially expressed genes identified, eight were confirmed by quantitative PCR analysis as differentially expressed, in addition to those already known to be associated with early lesions. G...
Stieler AL, Sanchez LC, Mallicote MF, Martabano BB, Burrow JA, MacKay RJ.The mechanism of hyperthermia, a potentially fatal adverse effect of erythromycin treatment of foals, is unknown. Objective: To determine the cause of erythromycin-associated hyperthermia. It was hypothesised that the normal sweat response of foals is impaired by treatment with erythromycin. Methods: Blinded, crossover study in 10 healthy pony foals. Methods: Foals kept in stalls were given either erythromycin (25 mg/kg bwt orally, 3 times daily) or control for 10 days then turned out for a further 10 days. Quantitative intradermal terbutaline sweat tests were performed on Days 1 (baseline)...
Bannai H, Nemoto M, Tsujimura K, Yamanaka T, Kondo T, Matsumura T.Virus-neutralizing (VN) testing is essential for evaluating virus-specific immunity in equine herpesvirus type-1 (EHV-1) infection. We developed a focus-reduction neutralization test (FRNT) for EHV-1 using 96-well plates for faster large-scale testing with sufficient sensitivity. We used an overlay medium containing Avicel (FMC Biopolymer), a microcrystalline cellulose with lower viscosity than the methylcellulose. The foci were visualized by immuno-staining with anti-EHV-1 gp14 monoclonal antibody. The FRNT successfully detected seroconversion in horses experimentally infected with EHV-1 (n =...
Magnuson NS, Perryman LE, Wyatt CR, Mason PH, Talmadge JE.Peripheral blood mononuclear cells from foals with hereditary severe combined immunodeficiency (SCID) have morphologic characteristics of large granular lymphocytes (LGL). Attempts to demonstrate cytotoxic activity were without success unless the LGL were incubated with 100 U of human recombinant interleukin 2 (rIL 2)/ml for 24 hr. With rIL 2 incubation, low effector to target ratios (10:1) consistently yielded high levels of cytotoxic activity (30 to 50%) in a standard 4-hr 51Cr-release assay using YAC-1 lymphoma or K562 erythroleukemia cell lines as targets. Monoclonal antibody EqT12 reacted...
Palmer JE.Few foals escape gastrointestinal disease during the first weeks of life. Diarrhea is an extremely common problem; fortunately, however, it is usually mild and self-limiting. When it is not, the underlying cause is often an infectious agent, such as rotavirus or Salmonella spp. Our understanding of many of the infectious agents causing neonatal diarrhea is far from complete. Gastric and duodenal ulcers are a less common disease of neonatal foals. There has been an apparent increase in the incidence of ulcer disease in foals during the past few years. The most effective way of decreasing seriou...
Buergelt CD.The few data collections that evaluate the involvement of organ systems in horse diseases are in agreement that the locomotor, gastrointestinal and nervous systems are the sites of primary disease in the vast majority of sick horses. When compared with diseases of these organ systems, equine cardiovascular diseases occur infrequently. The most detailed and comprehensive survey of equine cardiac pathology was reported in 1972 by Else and Holmes, who summarized the gross and microscopic cardiac findings from 1500 abattoir horses. This paper reviews the pathology of the cardiovascular diseases ty...
Upjohn MM, Shipton K, Pfeiffer DU, Lerotholi T, Attwood G, Verheyen KL.To establish baseline parameters of equine health, owner knowledge and husbandry practices and tack against which benefits to local horses arising from an equine charity's training programme in Lesotho could be measured. Objective: To describe and investigate associations between owner knowledge and equine husbandry practices, horse health and tack-related parameters prior to the start of the training programme. Methods: A cross-sectional survey was undertaken in the catchment area of students attending the first training course. Owners from randomly selected villages were interviewed about ho...
McGuire TC, Zhang W, Hines MT, Henney PJ, Byrne KM.Horses with equine infectious anemia virus (EIAV) have episodes of viremia and disease; however, most eventually become inapparent carriers. A possible mechanism of control is cytotoxic T lymphocytes (CTL). To evaluate CTL in inapparent carriers with low viral loads, peripheral blood mononuclear cells (PBMC) were stimulated in vitro with autologous EIAV-infected PBMC and human IL-2 to detect memory CTL (CTLm). In initial studies, three carriers had CTLm and one of these had low-level effector CTL (CTLe). The CTLm were restricted by equine lymphocyte alloantigen-A (ELA-A) locus encoded MHC clas...
Hurst EW.The virus of equine encephalomyelitis (eastern strain) evokes in the horse, calf, sheep and dog an unusually intense encephalomyelitis characterized by acute primary degeneration of nerve cells, the appearance in neurons of the brain stem and elsewhere of nuclear inclusions resembling those in Borna disease and poliomyelitis, polymorphonuclear infiltration in the nervous tissues with early microglial proliferation, and perivascular cuffing with mononuclears and polymorphonuclears in varying proportions. The grey matter is affected more than the white. Lesions may be less marked in the striatum...
Henson FM, Davenport C, Butler L, Moran I, Shingleton WD, Jeffcott LB, Schofield PN.The effects of insulin and insulin-like growth factors (IGFs) I and II on fetal and foal chondrocytes were investigated in vitro. Chondrocytes from the lateral trochlear ridge of the distal femur were obtained from 2 fetuses (280 and 320 days gestation) and one 4-day-old foal and cultured. Membrane proteins consistent with type 1 and type 2 IGF receptors were demonstrated by radioligand cross linking and equilibrium binding analysis. It was demonstrated that both IGF-I and IGF-II acted as mitogens for isolated equine chondrocytes when present as the sole mitogenic factor in monolayer culture. ...
Fritz KL, McCue ME, Valberg SJ, Rendahl AK, Mickelson JR.Recurrent exertional rhabdomyolysis is a heritable disorder that results in painful skeletal muscle cramping with exercise in up to 10% of all Thoroughbred racehorses. Here, we report a genome-wide association study with 48 282 SNPs analyzed among 48 case and 37 control Thoroughbreds. The most significant SNPs spanned approximately 13 Mb on ECA16, and the P-value of the most significant SNP after correcting for population structure was 8.0 × 10(-6) . This region on ECA16 was further evaluated by genotyping 247 SNPs in both the initial population and a second population of 34 case and 98 contr...
Brinkschulte M, Bienert-Zeit A, Lüpke M, Hellige M, Ohnesorge B, Staszyk C.Sinusitis is a common disease in the horse. In human medicine it is described, that obstruction of the sinonasal communication plays a major role in the development of sinusitis. To get spatial sense of the equine specific communication ways between the nasal cavity and the paranasal sinuses, heads of 19 horses, aged 2 to 26 years, were analyzed using three-dimensional (3D) reformatted renderings of CT-datasets. Three-dimensional models were generated following manual and semi-automated segmentation. Before segmentation, the two-dimensional (2D) CT-images were verified against corresponding fr...
Snow DH, Douglas TA, Thompson H, Parkins JJ, Holmes PH.Toxic effects of phenylbutazone (PBZ) in ponies and horses were studied, using a variety of biochemical, pathophysiologic, and pathologic methods. At dosage levels of 10 to 12 mg/kg of body weight/day for 8 to 10 days, ponies frequently developed clinical signs of toxicosis characterized by hypoproteinemia. Studies using 51CrCl3 demonstrated that PBZ caused a protein-losing gastroenteropathy. The plasma loss was usually associated with gastrointestinal ulceration, but sometimes occurred without obvious lesions in mildly affected animals. Similar studies (8.2 mg/kg/day for 13 days) in Thoroughb...
Sevane N, Sanz CR, Dunner S.Four loci seem responsible for the dilution of the basic coat colours in horse: Dun (D), Silver Dapple (Z), Champagne (CH) and Cream (C). Apart from the current phenotypes ascribed to these loci, pearl has been described as yet another diluted coat colour in this species. To date, this coat colour seems to segregate only in the Iberian breeds Purebred Spanish horse and Lusitano and has also been described in breeds of Iberian origin, such as Quarter Horses and Paint Horse, where it is referred to as the 'Barlink Factor'. This phenotype segregates in an autosomal recessive manner and resembles ...
Grobbel M, Lübke-Becker A, Alesík E, Schwarz S, Wallmann J, Werckenthin C, Wieler LH.A total of 417 isolates of Escherichia coli collected from five animal species/organ system combinations from swine [urinary/genital tract (UGT) incl. mastitis metritis agalactia syndrome], horses [genital tract (GT)] and dogs/cats [respiratory tract (RT), UGT and gastrointestinal tract (GIT)] were analysed quantitatively for their susceptibility against different antimicrobial agents by determination of minimum inhibitory concentrations. Regardless of which animal species the strains originated from, resistance appeared most frequently against sulfamethoxazole (18-59%), tetracycline (14-54 %)...
Pickles K, Pirie RS, Rhind S, Dixon PM, McGorum BC.Bronchoalveolar lavage fluid (BALF) samples are often subject to time delays, possibly with temperature fluctuations, between collection and processing. The aim of this study was to evaluate the effects of time, temperature and 2 different fixatives on equine BALF cytology, in order to develop guidelines for optimal equine BALF storage conditions. Total nucleated cell count (TCC), differential cell counts (DCC), absolute cell counts (ACC), cell viability, cell morphology and bacterial growth of BALF samples stored at 4, 18 (+/- addition of formalin- or alcohol-based fixatives) and 38 degrees C...
Maharana BR, Potliya S, Ganguly A, Bisla RS, Mishra C, Ganguly I.Equine ocular setariasis arising mainly from ectopic infestation of Setaria digitata is a common vision impairing ophthalmic disease in India, and the identification of this filarial nematode is based solely on morphology. However, morphological characters alone are inadequate to detect and differentiate S. digitata from its congeners. The present communication reports the first phylogenetic characterization of equine S. digitata from India based on sequences derived from the mitochondrial cytochrome c oxidase subunit 1 (COI), the mitochondrial small subunit ribosomal DNA (12S rDNA), and the n...
Walker RL, Madigan JE, Hird DW, Case JT, Villanueva MR, Bogenrief DS.An outbreak of salmonellosis in foals occurred on a large Thoroughbred farm in California. Only foals less than 8 days of age exhibited clinical signs, which included depression, anorexia, and diarrhea. Three foals died from septicemia. The agent responsible was Salmonella ohio, which is rarely involved in salmonellosis in horses. During the course of the outbreak, S. ohio was isolated from 27 of 97 mares (27.8%) and 34 of 97 foals (35.1%). Mares were the presumed source of infection for foals. The absence of clinical signs in mares allowed for increased exposure of foals through environmental...
Vijarnsorn M, Riley CB, Shaw RA, McIlwraith CW, Ryan DA, Rose PL, Spangler E.To evaluate use of infrared spectroscopy for diagnosis of traumatic arthritis in horses. Methods: 48 horses with traumatic arthritis and 5 clinically and radiographically normal horses. Methods: Synovial fluid samples were collected from 77 joints in 48 horses with traumatic arthritis. Paired samples (affected and control joints) from 29 horses and independent samples from an affected (n = 12) or control (7) joint from 19 horses were collected for model calibration. A second set of 20 normal validation samples was collected from 5 clinically and radiographically normal horses. Fourier transfor...
Blunden AS, Smith KC, Whitwell KE, Dunn KA.A severe multi-systemic form of equid herpesvirus-1 infection is described in an adult zebra stallion. There was multifocal necrotizing rhinitis, marked hydrothorax and pulmonary oedema, with viral antigen expression in degenerating epithelial cells, local endothelial cells and intravascular leucocytes of the nasal mucosa and lung. Specific localization of EHV-1 infection was seen in the testes and epididymides, including infection of Leydig cells and germinal epithelium, which would have facilitated venereal shedding of virus in life. The case provided a unique opportunity to study hitherto u...
Aleman M, Weich KM, Madigan JE.Horses are a precocious species that must accomplish several milestones that are critical to survival in the immediate post-birth period for their survival. One essential milestone is the successful transition from the intrauterine unconsciousness to an extrauterine state of consciousness or awareness. This transition involves a complex withdrawal of consciousness inhibitors and an increase in neuroactivating factors that support awareness. This process involves neuroactive hormones as well as inputs related to factors such as cold, visual, olfactory, and auditory stimuli. One factor not previ...
Taylor WTT, Bayarsaikhan J, Tuvshinjargal T, Bender S, Tromp M, Clark J, Lowry KB, Houle JL, Staszewski D, Whitworth J, Fitzhugh W, Boivin N.From the American West to the steppes of Eurasia, the domestic horse transformed human societies, providing rapid transport, communication, and military power, and serving as an important subsistence animal. Because of the importance of oral equipment for horse riding, dentistry is an essential component of modern horse care. In the open grasslands of northeast Asia, horses remain the primary form of transport for many herders. Although free-range grazing on gritty forage mitigates many equine dental issues, contemporary Mongolian horsemen nonetheless practice some forms of dentistry, includin...
Toth B, Aleman M, Brosnan RJ, Dickinson PJ, Conley AJ, Stanley SD, Nogradi N, Williams CD, Madigan JE.To test the hypothesis that application of a rope restraint device would result in behavioral, electroencephalographic, and humoral changes consistent with sleep and analgesia in neonatal foals. Methods: 8 healthy neonatal foals. Methods: Following acclimatization to experimental conditions, each foal underwent a series of assessments before and during or at the end of a period of restraint via application of a restraint device (soft linen rope). Assessments included measurements of heart and respiratory rates, rectal temperature, and circulating β-endorphin and steroid hormone concentrations...
Stannard AA, Cello RM.In a study of Onchocerca cervicalis infection in a sample of 100 horses from the western United States, 48 were infected. Infection was more common in older horses and occurred in both sexes equally. Data about the distribution and the concentration of microfilariae within the skin are presented. The only cutaneous pathologic change that could be attributed to microfilariae was minimal perivascular inflammatory cell infiltrate. Invasion of the eye with microfilariae occurred in 60 percent of the infected horses. An attempt was not made to relate microfilarial invasion of the eye with ocular pa...
Giles CJ.Five out of 20 horses (25 per cent) on one farm died from an acute hepatic encephalopathy typical of ragwort toxicosis. Circumstantial evidence implicated pasture rather than hay as the principal source of the toxic alkaloids. Plasma levels of gamma glutamyl transferase (GGT) were determined on three occasions in all surviving ragwort-exposed horses. Elevated GGT levels were a useful early indicator of hepatic damage although not all horses with this biochemical sign developed clinical disease.
Cokelaere SM, Martens AM, Wiemer P.To describe use of a polyamide tie-rap to ligate the mesovarium during standing laparoscopic ovariectomy in mares. Methods: Prospective study. Methods: Ten mares. Methods: Bilateral ovariectomy was performed in 10 mares. Standing laparoscopic ovariectomy was performed using 3 portals in the paralumbar fossa. A commercial polyamide tie-rap was prepared as a loop and marked with 4 colored lines close to the buckle, to enable us to check whether the loop was tightened securely. The ovary was grasped with forceps and after the mesovarium was minimally transected cranially and caudally, the loop of...
Schwartz EJ, Vaidya NK, Dorman KS, Carpenter S, Mealey RH.Understanding the dynamics of acute viral infection is crucial for developing strategies to prevent and control infection. In this study, lentiviral dynamics in a host without adaptive immunity were examined in order to determine kinetic parameters of infection and quantify the effect of neutralizing antibodies in preventing infection, using mathematical modeling of data from equine infectious anemia virus (EIAV) infection of horses with severe combined immunodeficiency (SCID). Estimated parameters were used to calculate the basic reproductive number and virus doubling time and found that the ...
Simões J, Sales Luís JP, Tilley P.Severe equine asthma (SEA) syndrome is a chronic recurrent respiratory disease, common among adult horses. The disease occurs in genetically susceptible individuals after their exposure to organic dust. Thus, environmental management has proved essential in controlling airway challenge and disease exacerbation. This is a demanding process that can only be achieved through the horse owners' cooperation. One year after initial diagnosis of SEA in a group of 39 horses, owner compliance to an environmental management protocol was evaluated. The overall compliance to the protocol was poor and the h...
Van Biervliet J.The practice of equine neurology has special challenges posed by the size of the animal being examined. Many diagnostic procedures routinely used in small animal practice are unsafe when applied to the equine patient or unavailable to the equine practitioner. Therefore, astute observation is the mainstay of making a neuroanatomic diagnosis, and detailed evidence on the deficits present may be difficult to obtain. Because clinical observation can sometimes be ambiguous and somewhat subjective, it is even more important to approach equine neurology from an evidence-based point of view. Here, suc...
Higgins AJ, Lees P, Sedgwick AD.Two experimental models of acute non-immune inflammation have been developed to enable studies of the biochemical composition and cellular content of exudates to be undertaken. Both are based on the creation of a mild, reproducible and reversible inflammatory reaction, which is free from uncontrolled incidental factors and which causes minimal distress to the experimental animals. The polyester sponge model involves the insertion of small polyester sponge strips soaked in sterile carrageenan solution into subcutaneous neck pouches and their serial removal. The tissue-cage model is based on the...
Tennent-Brown BS.In hospitalized horses, hypovolemia and the resulting decrease in tissue perfusion is the most common cause of hyperlactatemia. Therefore, measurement of blood lactate concentration can be a useful tool for guiding fluid therapy. Similarly, measuring blood lactate concentration can be used to assess the need for and adequacy of transfusions in horses receiving whole blood. Inflammatory leukocytes within closed body cavities consume glucose and produce lactate. Simultaneous measurement of blood lactate concentration and lactate concentration of peritoneal, pleural, or synovial fluid has been us...
Nemoto M, Tsujimura K, Yamanaka T, Kondo T, Matsumura T.Loop-mediated isothermal amplification (LAMP) is a novel method for the rapid and sensitive detection of DNA without the need for expensive equipment. In the present study, LAMP assays were developed for the specific detection of Equid herpesvirus 1 and 4 (EHV-1 and EHV-4, respectively) and for the differentiation of glycoprotein E (gE)-deleted EHV-1 (DeltagE) strain, a candidate strain for a live vaccine, from field EHV-1 strains. Specific primer sets were designed for the gC and gE genes of EHV-1 and for the gC gene of EHV-4. The analytical sensitivities of the LAMP assays were compared with...
