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.
Hallebeek JM, van 't Klooster AT, Beynen AC.In various situations it is desirable to evaluate the diet of horses. Such situations occur when nutrition is considered as the cause of disease or symptoms or and when a diet or diet change raises concern about whether the animal is receiving sufficient nutrients. Ration evaluation consists of translating feed ingredients into nutrients supplied and comparing this with nutrient requirements. The basics of ration evaluation are illustrated by means of four examples of horse diets.
Oxburgh L, Hagström A.In this paper we describe the development of a nested RT-PCR assay for the rapid diagnosis and characterisation of influenza virus directly from clinical specimens. Viral RNA is extracted from nasal swabs by the guanidine thiocyanate extraction method, and subsequently reverse transcribed. The complementary DNA is then used as template in a nested PCR reaction. Primers designed for use in this assay are specific for three templates; (1) the nucleoprotein (NP) gene, (2) the haemagglutinin gene of the H7N7 equine influenza virus (A1), and (3) the haemagglutinin gene of the H3N8 equine influenza ...
Grubb TL, Constable PD, Benson GJ, Foreman JH, Olson WO, Thurmon JC, Tranquilli WJ, Davis LE.To determine the most repeatable method for evaluating right ventricular relaxation rate in horses and to determine and compare effects of isoflurane or halothane with and without the added influence of intravenously administered calcium gluconate on right ventricular relaxation rates in horses. Methods: 6 Thoroughbred horses from 2 to 4 years old. Methods: 6 models (2 for monoexponential decay with zero asymptote, 3 for monoexponential decay with variable asymptote, and 1 for biexponential decay) for determining right ventricular relaxation rate were assessed in conscious and anesthetized hor...
Hare JE, Viel L, Conlon PD, Marshall JS.To determine the capacity of pulmonary mast cells (PMC) to degranulate in response to various potential allergens and other secretagogues in horses with recurrent airway obstruction (heaves) and clinically normal horses before and after exposure to moldy hay. Methods: 5 horses with heaves and 5 clinically normal horses. Methods: Heaves was characterized as an increased clinical respiratory score and maximum change in transpulmonary pressure of > 20 cm H2O after exposure. Bronchoalveolar lavage was performed during each period. Washed and resuspended cells were exposed for 20 minutes at 37 C wi...
McConnico RS, Weinstock D, Poston ME, Roberts MC.To determine whether quantification of myeloperoxidase (MPO) activity could be a useful laboratory technique to detect granulocyte infiltration in equine intestinal tissues. Methods: Intestinal tissue (inflamed or healthy) collected from 16 age- and sex-matched Shetland Ponies. Methods: Intestinal tissue MPO activity was determined, and histologic assessment of adjacent specimens from healthy and inflamed intestine was done. Results: Intestinal tissue MPO activity and histopathologic score increased with time after castor oil challenge and peaked at 16 hours in an equine diarrhea model in whic...
Hong CB, Van Meter PW, Latimer CL.A malignant rhabdoid tumour was diagnosed in the orbit of a 2-year-old Thoroughbred filly. The neoplasm, which was very aggressive, was present in nearly every part of the ocular and periocular structures and had spread to the lymph nodes of the head and neck, the salivary glands and the subcutaneous tissues around the eye. The neoplasm was composed of polygonal cells with abundant eosinophilic cytoplasm. Many cells had a large, vesiculate, indented nucleus and contained a paranuclear globular inclusion. Ultrastructurally, the inclusions were seen to consist of whorls of intermediate filaments...
Balasuriya UB, Snijder EJ, van Dinten LC, Heidner HW, Wilson WD, Hedges JF, Hullinger PJ, MacLachlan NJ.Virus derived from an infectious cDNA clone of equine arteritis virus (EAV030H) was intranasally inoculated into two stallions, neither of which subsequently developed clinical manifestations of equine viral arteritis (EVA). Virus was isolated from nasal swabs and mononuclear cells collected from both stallions
Smets K, Shaw DJ, Deprez P, Vercruysse J.Between October 1996 and May 1997, 94 horses which were suspected of being infected with strongyles were examined clinically, and samples of faeces were examined for strongyle eggs and cyathostome larvae (L4) and adults. Blood samples were monitored for total protein, albumin and beta-globulins. In 28 of the horses (30 per cent) cyathostome L4 and adults were detected in the faeces, and were significantly associated with the horses' condition, the occurrence of diarrhoea, with lower concentrations of total protein and albumin, and with higher percentages of beta-globulin. Thirty-four of the ho...
Denoix JM, Busoni V.The ultrasonographic anatomy of the accessory ligament of the superficial digital flexor tendon (AL-SDFT) in the horse is presented. Comparison between anatomical sections of isolated limbs and ultrasound scans of the distal antebrachium in sound horses enabled the authors to establish the normal reference ultrasonographic images of this structure. The AL-SDFT inserts 7-14 cm above the antebrachiocarpal joint on the palmaromedial aspect of the radius. Ultrasonographically it appears as an uniformly echogenic structure located deep to the median artery. The knowledge of ultrasonographic anatomy...
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 ...
Miller MM, Sweeney CR, Russell GE, Sheetz RM, Morrow JK.To determine effects of blood contamination on western blot (WB) analysis of CSF samples for detection of anti-Sarcocystis neurona antibodies, and on CSF albumin and IgG concentrations, albumin quotient (AQ), and IgG index in horses. Methods: Prospective in vitro study. Methods: Blood with various degrees of immunoreactivity against S neurona was collected from 12 healthy horses. Cerebrospinal fluid without immunoreactivity against S neurona was harvested from 4 recently euthanatized horses. Methods: Blood was serially diluted with pooled nonimmunoreactive CSF so that final dilutions correspon...
Ramina A, Dalla Valle L, De Mas S, Tisato E, Zuin A, Renier M, Cuteri V, Valente C, Cancellotti FM.The reverse transcriptase polymerase chain reaction (RT-PCR) assay was used to detect Equine Arteritis Virus (EAV) in the semen of 88 horses and 2 donkeys, with neutralising antibodies against EAV, on the basis of the amplification of a 279 bp long fragment located in the viral polymerase gene. The RT-PCR assay revealed the virus at 4 TCID50/ml in cell culture and showed a greater sensitivity (54.4%) than cell culture isolation (33.3%). Moreover, the two samples of donkey semen were found positive. The cDNAs obtained from 14 samples of horse and 2 of donkey semen were sequenced. Comparing the ...
Gardelle O, Feige K, Geissbühler U, Geyer H, Schmucker N, Sydler T, Kaser-Hotz B.For the past 2 years computed tomography is used at the Veterinary School, University of Zürich. This new imaging modality enables the detection of abnormalities occurring in small and large animals which were previously not visible with imaging techniques. Subjects of this study were a foal and a small pony, both with suspected head trauma. Routine radiography could not explain any of the neurological deficiencies. In the first case a basilar skull fracture along with a focal brain hemorrhage was detected, in the second case multiple basilar skull fractures were seen. The computed tomographi...
Raabe ML, Issel CJ, Montelaro RC.We have previously demonstrated a high propensity for enhancement of virus replication and disease resulting from experimental immunization of ponies with a baculovirus recombinant envelope (rgp90) vaccine from equine infectious anemia virus (EIAV). The current studies were undertaken to examine the correlation between the observed in vivo vaccine enhancement and in vitro assays for antibody-dependent enhancement (ADE) of EIAV replication. Toward this goal an optimized EIAV in vitro enhancement assay was developed using primary equine macrophage cells and used to evaluate the enhancement prope...
Ross WA, Kaneene JB, Caron JP, Gallagher KF, Gardiner JC.The objective of this study was to identify factors that may affect recovery from and duration of a case of lameness in a stratified random sample of Michigan horses. This was done using data from Phase-II of the Michigan equine monitoring system (MEMS Phase-II), the equine health-monitoring study [Kaneene et al., Prev. Vet. Med. 29 (1997b) 277-292; Ross and Kaneene, Prev. Vet. Med. 28 (1996a) 209-224; Ross and Kaneene, Prev. Vet. Med. 29 (1996b) 59-75; Ross et al., Am. J. Vet. Res. 59 (1997) 23-29]. In this study, statistical modelling was conducted to evaluate risk factors affecting recovery...
Kaiser B, Koene M, Swagemakers J, Bader H, Hoppen HO.During the 1997 breeding season persistent follicles were diagnosed in 17 mares. In 16 of these mares a total of 17 follicles were transabdominally punctured and the steroids oestradiol, progesterone and testosterone were measured in the follicular fluid and in blood serum. In ten mares serving as a control group preovulatory follicles were punctured. The follicular fluid of the persistent follicles revealed a very high variability of the steroid concentrations. Depending on the steroid ratio within the follicles, eight follicles were rated as being intact, three follicles were undergoing atre...
Rush BR, Hoskinson JJ, Davis EG, Matson CJ, Hakala JE.To determine whether pulmonary distribution of aerosolized technetium Tc 99m pentetate is improved after inhalation of a single dose of albuterol sulfate in horses susceptible to recurrent airway obstruction (heaves). Methods: 6 horses with heaves and 4 horses with normal respiratory tract function. Methods: Images were obtained during ventilation of horses at baseline (maximal change in pleural pressure during tidal breathing [deltaPpImax] >15 cm H2O) and after aerosolized albuterol sulfate (360 microg) administration, with a 24-hour washout period between experiments. The deltaPpImax was ...
Derksen FJ, Olszewski MA, Robinson NE, Berney C, Hakala JE, Matson CJ, Ruth DT.To determine the dose of aerosolized albuterol sulfate required to cause bronchodilation in horses with recurrent airway obstruction (RAO) and duration of this effect. Methods: 19 horses with RAO (10 in experiment 1; 9 in experiment 2). Methods: Horses were moved from pasture to stables, and airway obstruction was induced. Pulmonary function was measured in 10 horses before and 5, 10, and 30 minutes after administration of vehicle or 120, 240, 360, or 720 microg of the drug. Nine horses received vehicle or 360 or 720 microg of albuterol, and pulmonary function was measured at baseline and 5 mi...
Lentz LR, Valberg SJ, Mickelson JR, Gallant EM.To determine whether increased sensitivity to pharmacologic agents was a general property of equine exertional myopathies, including polysaccharide storage myopathy (PSSM) in Quarter Horses. Methods: 5 adult Quarter Horses with exertional rhabdomyolysis and abnormal polysaccharide accumulation in skeletal muscle and 4 clinically normal adult Quarter or Quarter-type horses. Methods: Twitch time course measurements and contracture responses to various concentrations of caffeine and halothane for small bundles of intact external intercostal muscle fibers were measured in all horses. Results: Caff...
Carrasco L, Sánchez C, Gómez-Villamandos JC, Laviada MD, Bautista MJ, Martínez-Torrecuadrada J, Sánchez-Vizcaíno JM, Sierra MA.African horse sickness (AHS) is a disease of equids, characterized by severe pulmonary oedema and caused by an orbivirus. To determine the role of pulmonary intravascular macrophages (PIMs) in the development of pulmonary microvascular changes in this disease, five horses were given an intravenous inoculation of 10(6)TCID50of serotype 4 of AHS virus. Viral replication was detected in endothelial cells, PIMs, interstitial macrophages and fibroblasts. Alveolar and interstitial oedema, and changes in pulmonary microvasculature, consisting mainly of the sequestration of neutrophils and the formati...
Simmons EJ, Bertone AL, Hardy J, Weisbrode SE.To quantitate nitric oxide synthase (NOS) activity in healthy and interleukin 1beta (IL-1beta)-exposed equine synovial membrane. Methods: 6 healthy horses, 2 to 8 years old. Methods: Recombinant human IL-1beta (0.35 ng/kg of body weight) was injected intra-articularly into 1 metacarpophalangeal joint of each horse. The contralateral joint served as an unexposed control. All horses were euthanatized 6 hours after injection of IL-1beta, and synovial membrane specimens were assayed for NOS activity by measuring conversion of arginine to citrulline. Severity of inflammation was semiquantitated by ...
Frank N, Sojka JE, Latour MA, McClure SR, Polazzi L.To measure and compare concentrations of selected blood lipids before and after thyroidectomy in horses. Methods: 5 healthy adult mares. Methods: Mares were confirmed to be euthyroid. Thyroidectomy was performed, and hypothyroidism was confirmed. Selected blood lipid variables were measured before hypothyroidism was induced and weekly for 4 weeks after induction. Plasma concentrations of very low-density lipoprotein (VLDL), low-density lipoprotein (LDL), serum triglyceride (TG), total cholesterol (TC), and nonesterified fatty acid (NEFA) were measured. The composition of VLDL and LDL also was ...
Grulke S, Benbarek H, Caudron I, Deby-Dupont G, Mathy-Hartert M, Farnir F, Deby C, Lamy M, Serteyn D.Myeloperoxidase (MPO) is a specific enzyme of neutrophil azurophilic granules with a strong oxidative activity. Thanks to a radioimmunoassay of equine myeloperoxidase, the authors have observed a significantly higher plasma level of MPO in horses operated for strangulation obstruction of the large intestine (n = 6) than in horses suffering from a non-strangulating displacement of the large intestine (n = 9). For the 2 groups, 3 phases were distinguished: reception (P1), intensive care (P2) and terminal phase (P3). The mean peak values of MPO for these phases were 121.6 ng/mL (P1), 168.6 ng/mL ...
Patton JF, Balasuriya UB, Hedges JF, Schweidler TM, Hullinger PJ, MacLachlan NJ.An avirulent, novel variant of equine arteritis virus (EAV; CA95G) was isolated from the semen of a persistently infected Standardbred stallion. The CA95G virus caused subclinical infection and seroconversion in susceptible horses, and virus was isolated only once from blood and nasal secretions collected from 6 experimentally infected horses. Sequence analysis of genes encoding the known EAV structural proteins shows that this highly attenuated strain of EAV is genetically similar to virulent field strains of EAV and, in particular, to a strain of EAV that was isolated during an outbreak of e...
Russell KE, Perkins PC, Hoffman MR, Miller RT, Walker KM, Fuller FJ, Sellon DC.Thrombocytopenia is a consistent finding and one of the earliest hematological abnormalities in horses acutely infected with equine infectious anemia virus (EIAV), a lentivirus closely related to human immunodeficiency virus. Multifactorial mechanisms, including immune-mediated platelet destruction and impaired platelet production, are implicated in the pathogenesis of EIAV-associated thrombocytopenia. This study was undertaken to investigate whether regenerative thrombopoiesis and platelet destruction occurred in ponies acutely infected with EIAV. Circulating large, immature platelets were in...
Kappmeyer LS, Perryman LE, Hines SA, Baszler TV, Katz JB, Hennager SG, Knowles DP.A competitive-inhibition enzyme-linked immunosorbent assay (cELISA) was developed for detection of equine antibodies specific for Babesia caballi. The assay used recombinant B. caballi rhoptry-associated protein 1 (RAP-1) and monoclonal antibody (MAb) 79/17.18.5, which is reactive with a peptide epitope of a native 60-kDa B. caballi antigen. The gene encoding the recombinant antigen was sequenced, and database analysis revealed that the gene product is a rhoptry-associated protein. Cloning and expression of a truncated copy of the gene demonstrated that MAb 79/17.18.5 reacts with the C-termina...
Hoque S, Derar RI, Senba H, Osawa T, Kano K, Taya K, Miyake Y.To clarify the morphological and immunohistochemical characteristics in mares with granulosa theca cell tumor (GTCT), the localization of inhibin subunits (alpha, betaA, betaB) and aromatase in the granulosa cell layers and theca layers in the ovarian follicles were determined by immunohistochemical staining. The follicles were obtained from the ovaries of 6 mares with GTCT and 4 normal mares as controls. Immunohistochemically, inhibin alpha-subunit was localized in the granulosa cells of all follicles showing different sizes in all GTCT cases and betaA- subunit was localized in two GTCT cases...
Lorenzo-Figueras M, Pusterla N, Byrne BA, Samitz EM.To evaluate the effectiveness of a commercial conventional blood culture system (BCS), a commercial resin-containing BCS, and a commercial lysis-centrifugation-based BCS for the recovery of Escherichia coli from equine blood samples inoculated with that organism. Methods: Samples of blood obtained from a clinically normal horse that were inoculated with E coli. Methods: Blood samples were aseptically collected and inoculated with an E coli specimen (50 CFUs/mL) that had been previously isolated from a foal with sepsis. Subsequently, samples were spiked with gentamicin at a concentration of 30 ...
Popot MA, Jacobs M, Garcia P, Loup B, Guyonnet J, Toutain PL, Bailly-Chouriberry L, Bonnaire Y.Tiludronate is a bisphosphonate drug marketed to treat different bone conditions in horses. Objective: The goal of this study was to measure the plasma concentrations of tiludronate in a population of race and sport horses under field conditions, and using pharmacokinetic population modelling, to estimate detection times for doping control. Methods: Prospective cohort. Methods: This study was conducted under field conditions on 39 race or sport horses diagnosed with bone conditions based on a lameness examination and treated with tiludronate. Each horse received 1 mg/kg of tiludronate (Tildren...
Köllmann M, Rötting A, Heberling A, Sieme H.The diagnostic and therapeutic options for oviduct disorders in the mare are limited. The current best techniques require exploratory surgery under general anaesthesia or flank laparotomy. Objective: The orthograde flushing of the oviduct for diagnostic or therapeutic options is possible using laparoscopic techniques in the standing sedated mare. Methods: Development of a laparoscopic technique for catheterisation of the infundibulum and flushing of the oviduct (sterile methylene blue solution) in the standing sedated mare was examined in 2 experiments. The first involved a transvaginal laparo...
Cummings JF, de Lahunta A, Timoney JF.Four cases of neuritis of the cauda equina (NCE) were studied by light and electron microscopy. Examination of sacral intradural rootlets revealed inflammatory cell infiltrates and an array of myelinated fiber changes which included myelin stripping by invading mononuclear cells and macrophages, as well as splitting and vesiculation of myelin lamellae without obvious participation by leukocytes. More distally in the extradural roots, there was marked granulomatous inflammation, and demyelinative changes were overshadowed by widespread evidence of irreversible axon damage. In all cases, unusual...
Furr M.Diagnosis of neuro-inflammatory conditions in the horse can be challenging. Current methods include evaluation of cerebrospinal fluid (CSF) for inflammation and determination of specific antibody status. The antibody index (AI) and Goldman-Witmer coefficient (C-value) can be used to aid in the interpretation. Objective: The null hypothesis to be tested was that the Al and C-values do not change in horses with neuroinflammation. Methods: Twelve horses of various ages (3-17 years) and breeds (Thoroughbred, Thoroughbred cross, draft, and Arabian) were included in the study. Methods: The study was...
Rebhun WC.Corneal squamous cell carcinomas with surface areas of more than 2.0 cm were diagnosed in 26 eyes of 25 horses. The depth of the lesion into the corneal stroma and involvement of the ocular adnexa were important determinants for surgical treatment. Corneal tumors that extended into adjacent palpebral conjunctiva, eyelid, or orbit were not amenable to complete excision, while those that involved only cornea and bulbar conjunctiva were treated surgically by keratectomy and beta radiation. Initial treatment was keratectomy followed by beta radiation on 24 eyes and enucleation of two eyes. Twenty ...
Infectious causes of myositis are reported relatively uncommonly in horses. Among them, bacterial causes include subsp. , , spp. spp, and . Infection can be spread to muscles via haematogenous or extension from skin lesions. Parasitic myositis has also been documented. In this report, a 12 year-old Italian Quarter Horse mare presented with diffuse subcutaneous nodules and masses ranging from 2 × 3 to 5 × 20 cm in size, and adherent to subcutis and muscles that were first macroscopically and cytologically diagnosed as pyogranulomas. Subsequently, histological, molecular, bacteriological, a...
Tomlinson JE, Sage AM, Turner TA, Feeney DA.To map the equine pelvis using ultrasonography, validated by use of computed tomography (CT), magnetic resonance imaging (MRI), and measurements of frozen cadaver slices. Methods: 6 ponies and 6 horses. Methods: Ultrasonographic examination of the pelvis was performed on 6 clinically normal ponies. Measurements were obtained for imaged structures. Computed tomography, MRI, and measurements of frozen sections were performed after death and used to verify measurements. Linear regression determined the degree of correlation between measurements obtained ultrasonographically and the other modaliti...
Ruggles AJ, Ross MW.Medical records of 28 horses with impaction of the small colon were reviewed; 20 horses were admitted during the winter months. Diagnosis of small-colon impaction was made in 21 horses by rectal examination, and in 7 horses at exploratory celiotomy. Ten horses were treated medically, and 18 were treated surgically. Horses that were treated surgically were more likely to have abdominal distention than were those that responded to medical treatment (P less than 0.025). Signs of greater degree of abdominal pain and higher heart rate were seen in horses treated surgically, but these values were no...
McGuire TC, Banks KL, Evans DR, Poppie MJ.Agammaglobulinemia was diagnosed in a 1-year-old Thoroughbred horse on the basis of the following observations: (1) absence of serum immunoglobulins M, A, and G(T); (2) small amounts of serum immunoglobulin G (16 mg/100 ml); (3) absence of specific antibody in the serum of the horse following immunization and challenge exposure to 2 antigens; (4) absence of plasma cells, primary follicles, and germinal centers in a lymph node removed after antigenic stimulation; (5) absence of "natural" serum antibodies to rabbit-erythrocytes which were easily detectable in age-matched control horse serums; an...
Mawhinney I, Errington J, Stamper N, Torrens N, Engelsma MY, Roest HIJ.Sets of genital swabs are routinely taken from horses to screen for the presence of Taylorella equigenitalis, the cause of contagious equine metritis. Typically, two to four different sites are swabbed at a time and tested by culture or PCR. Objective: This study explored the feasibility of pooling these swabs for a single PCR test per animal instead of testing each swab individually. Methods: In vitro. Methods: PCR signal strengths (Ct values) from 149 historical PCR positive genital swabs, together with historical data on the number of swabs in a set expected to be positive, were used to ass...
Dewes HF, Townsend KG.Two horses repeatedly underwent episodes of frenzy characterised by extreme discomfort and hyperactivity. Within 2 days of an attack the lower extremities of both hind legs of one subject were uniformly swollen, while on the second subject skin lesions erupted 3-4 days after an attack and swelling persisted for 2-3 weeks. Filariform larvae of Strongyloides westeri were cultured from soil and sawdust where the subjects were kept. Larvae were cultured from soil of low pH (4.5-5.8) but were absent from neutral or alkaline soils. Larvae were found in sawdust with a wide pH range. It is thought tha...
Aleman MR, True A, Scalco R, Crowe CM, Costa LRR, Chigerwe M.Irreversible sensorineural auditory loss has been reported in humans treated with aminoglycosides but not in horses. Objective: Investigate if auditory loss occurs in horses treated using the recommended IV daily dosage of gentamicin for 7 consecutive days. Methods: Ten healthy adult horses (7-15 years; females and males, 5 each). Methods: Prospective study. Physical and neurological examinations and renal function tests were performed. Gentamicin sulfate was administered at a dosage of 6.6 mg/kg via the jugular vein on alternating sides for 7 days. Gentamicin peak and trough concentratio...
Trueman KF, Lumsden JH, McSherry BJ.Serum alkaline phosphatase activity was found to be increased in 32.6% of equine samples analyzed at the Ontario Veterinary College over an 18 month period. An attempt was made using sensitivity to L-phenylalanine and heat to identify the origin of increased serum alkaline phosphatase isoenzymes present in 44 clinical cases. No difference in sensitivity to either procedure was observed for serum alkaline phosphatase from groups of foals and horses representing different clinical problems. Alkaline phosphatase of osseous tissue origin appeared to be the major source of activity for each group o...
McClure S, Sibert G, Hallberg J, Bade D.The efficacy and safety of sustained release ceftiofur administered twice, 4 days apart, for treatment of horses with naturally acquired Streptococcus equi subsp. zooepidemicus (Strep. zoo.) pneumonia was evaluated in a multicenter, placebo-controlled, double-blinded, randomized clinical trial. The study included 373 horses (278 treated and 95 placebos) with naturally acquired pneumonia. Inclusion in the statistical analyses for treatment efficacy for Strep. zoo. required recovery of ≥10(4) CFU/mL of Strep. zoo. on the primary isolation plate which resulted in 201 cases (145 treated and 56 p...
Salmonella enterica subsp. enterica serovar Abortusequi (S. Abortusequi) is a serotype restricted to equines, which produces abortion outbreaks. Nowadays the disease is being reported in different countries including Argentina thus generating an important impact in the equine industry. Molecular characterization of the 95 kb virulence plasmid and the spvC gene of S. Abortusequi demonstrated their importance in the pathogenicity of the serotype. In the last decades, high clonality of S. Abortusequi was identified in Japan, Mongolia and Croatia. Objective: The aim of this work was to characteriz...
Sallé G, Cortet J, Koch C, Gascogne T, Reigner F, Cabaret J.Drug resistance in equine gastro-intestinal parasitic nematodes has been reported throughout the world. While the focus is usually put on cyathostomins, observations of macrocylic lactone failure against Oxyuris equi have accumulated over the last decade. Here we report the failure of ivermectin in the control of O. equi in an experimental Welsh pony herd. In a first trial, 6 ponies previously drenched with moxidectin and showing patent O. equi infections were administered ivermectin and subsequently monitored for O. equi egg excretion over one month. This trial demonstrated a failure of iverm...
Devick IF, Hendrickson DA.To describe a standing left paralumbar fossa approach combined with mesocolon fenestration for bilateral equine ovariectomy. Methods: Prospective experimental clinical study. Methods: Four healthy client-owned mares and 1 client-owned Molly mule. Methods: Mares were restrained in standing stocks and sedated with an α -agonist continuous infusion to effect. The abdominal cavity was approached via a left paralumbar fossa approach, and the contralateral right ovary was accessed through an incision in the mesocolon. The location of the window was adjusted to allow triangulation, adequate visualiz...
Cummings JF, Sellers AF, Lowe JE.The distribution of the putative motor excitatory neurotransmitter, substance P, was studied immunocytochemically in the left dorsal colon of four normal control ponies and three ponies with amitraz-induced impaction colic. Substance P-like immunoreactivity in the control ponies was observed in nerve fibres in all layers of the bowel wall and in the nerve cell bodies of the enteric ganglia. The substance P-like immunoreactivity was clearly more intense in the cell bodies of submucosal ganglia than in those of the myenteric ganglia. The internodal nerve strands of the myenteric plexus were very...
Lumsden HJ, Valli VE, McSherry BJ, Robinson GA, Claxton MJ.The hematological response to acetylphenylhydrazine hemolytic anemia was studied in three standardbred horses. The lifespan of erythrocytes produced during the most severe phase of the anemia were measured with 75-selenomethionine and found to be 144 days as compared to the 139 day lifespan in response to hemorrhagic anemia or 155 days in normal standardbred horses measured previously using the same technique. The erythrocyte counts returned to initial values in 42 days (37, 34 and 54 days) a mean erythrocyte production of 6.4 times 10-12 erythrocytes/day. The mean hemoglobin production was 0....
Walter I, Klein M, Handler J, Aurich JE, Reifinger M, Aurich C.To evaluate changes of glycoconjugate in uterine glands of endometrial tissues obtained from mares. Methods: adult mares. Methods: Uterine biopsy samples were collected during the breeding season and analyzed histologically for signs of chronic endometrial degeneration. Stage of the estrous cycle was established, using clinical examination and determination of hormonal status. Uterine tissue samples were analyzed, using lectin histochemical and immunohistochemical techniques (estrogen and progesterone receptors). Connective tissues were stained to determine alterations of ground substance in p...
Vanhaesebroeck B, Grooten J, Fiers W.Using a model of local lymph node (LN) immunization, we investigated the effect of in vivo Ir on the generation of lymphokine-activated killer (LAK) cells or their precursors. Ag used for immunization were SRBC, horse RBC, OVA, keyhole limpet hemocyanin, or CFA. Ag-draining LN, in the acute phase of the Ir, did not contain detectable LAK effector activity, nor an enhanced NK activity. After culture for 3 to 5 days in the absence of exogenously added IL-2, immunized LN cells developed a spontaneous LAK-like cytotoxicity. This activity represented a substantial fraction of the IL-2-generated LAK...
Kweon CH, Kwon BJ, Ko YJ, Kenichi S.VP7, the sero-group common antigen, of African horsesickness virus (AHSV-4) was expressed in insect cells by recombinant baculovirus. To develop a specific diagnostic method, monoclonal antibody (Mab) against VP7 was prepared and investigated as diagnostic reagent with the baculovirus expressed VP7. However, the Mab against VP7 of AHSV cross-reacted with Chuzan virus by the indirect immunofluorescence assay (IFA), confirming the presence of conserved domain of VP7 among Orbiviruses. This study describes two types of ELISA; Mab linked indirect (I-ELISA) and competitive-ELISA (C-ELISA) using bac...
Singh BK, Ahuja S, Gulati BR.A single-dilution, sensitive and specific monoclonal antibody-based blocking enzyme-linked immunosorbent assay (B-ELISA) was developed as an alternative to the cumbersome virus neutralization test (VNT) for detection of equine herpesvirus-1 (EHV-1) antibodies. Neutralizing monoclonal antibodies (1H6 and 9C6) raised against EHV-1 (Hisar-90-7 strain) and sera from 70 horses (30 known negative and 40 known positive for EHV-1 antibodies by VNT) were used for standardization of the B-ELISA. Using a single serum dilution of 1:250 in B-ELISA, 100% specificity was obtained with both monoclonal antibod...
Nikles SA, Heath TJ.The intestine of horses differs from that of most other domestic animals in having a huge ascending colon and cecum, which together act as a large fermentation vat. The lymph drainage from this intestine occurs through a complex network of lymph vessels and lymph nodes, of which there are several thousand. The pathways taken by lymph through these vessels and nodes were studied by tracing injections of dye, by examining Microfil casts, and with light and transmission electron microscopy. Lymph vessels transporting lymph from the intestinal wall generally terminate on a single node within a gro...
Tanaka Y, Adilbish A, Koyama K, Bayasgalan MO, Horiuchi N, Uranbileg N, Watanabe K, Purevdorj B, Gurdorj S, Banzragch B, Badgar B, Suganuma K....Dourine is a deadly protozoan disease in equids caused by infection with Trypanosoma equiperdum. Neurological signs in the later stage of infection may be caused by peripheral polyneuritis and related axonal degeneration. This neuritis involves T lymphocytes, B lymphocytes, and macrophages, and is observed in cases without obvious neurological signs. However, the pathogenesis of neuritis remains unclear. We identified M2 macrophages and CD8 T cells as the predominant phenotypes in neuritis of dourine-affected horses with or without neurological signs. In contrast, the populations of M1 macroph...
Andrade FSRM, Ambrósio AM, Rodrigues RR, Faccó LL, Gonçalves LA, Garcia Filho SG, Dos Santos RT, Rossetto TC, Pereira MAA, Fantoni DT.Electrical impedance tomography (EIT) has been an essential tool for assessing pulmonary ventilation in several situations, such as the alveolar recruitment maneuver (ARM) in PEEP titration to maintain the lungs open after atelectasis reversion. In the same way as in humans and dogs, in horses, this tool has been widely used to assess pulmonary aeration undergoing anesthesia, mechanical ventilation, recruitment maneuver, standing horses, or specific procedures. Unassigned: The present study aimed to evaluate the distribution of regional ventilation during ARM based on lung monitoring assessmen...
Cahill JI, Goulden BE, Jolly RD.A detailed investigation of the neuropathology of a horse affected with stringhalt was performed. Qualitative and quantitative light and electron microscopy, and single teased fibre preparations of peripheral nerve demonstrated predominantly axonal degeneration, the stage of which was appropriate for the duration of clinical signs. There was selective involvement of large myelinated nerve fibres. A proximal to distal increase in the severity of pathological changes was present in the peripheral nerves. The long left recurrent laryngeal nerve was the most severely affected, followed in order by...
Kubota T, Inaba Y, Uwatoko K, Akashi H, Fukunaga Y.Equine arteritis virus (EAV) grown on RK13 cell cultures was tested for hemagglutination (HA) with erythrocytes from a variety of species at 4 degrees C, room temperature and 37 degrees C. HA was observed at all temperatures with erythrocytes from mouse and chicken but not with those of cattle, horse, rabbit, guinea pig, mongolian gerbil, goose or chick embryo. Chickens showed an individual variation in agglutinability of their erythrocytes, requiring selection of birds to obtain erythrocytes for HA. The HA activity was enhanced by treatment of virus materials with Tween 80 followed by treatme...
