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.
Huhtinen M, Reilas T, Katila T.The pregnancy rate is lower in mares inseminated at the first post-partum (p.p.) oestrus (40-50%) compared with pregnancy rates in subsequent oestrous cycles (55-65%). The causes of the lowered pregnancy rate are not fully understood. The aim of the present study was to examine if embryonic defects could be one of the reasons for lowered pregnancy rate. A total of 23 p.p. and 14 non-lactating control mares were flushed 7 days after detection of ovulation. Embryo recovery rate was 48% and 71% in p.p. and control mares, respectively (p = 0.16). Embryos were photographed, measured, graded and sta...
Smith RF, Jackson LS, Moore A.An 125I radioimmunoassay to determine the pattern of urinary excretion of etorphine (a semisynthetic opiate agonist) after its administration to horses is described. Three thoroughbred horses were each given 5, 15, 30 and 100 micrograms of etorphine intramuscularly. Urine was collected for up to 72 after administration. The maximum etorphine concentration after administration of a dose of 5 micrograms was 711 pg ml-1 (concentrations were greater than 100 pg ml-1 after 23 h in all three horses); a 15 micrograms gave 2661 pg ml-1 (levels remained above 100 pg ml-1 for more than 44 h in each hors...
Grier SJ, Turner AS, Alvis MR.The use of dual-energy absorptiometry (DXA) to measure bone mineral content (BMC) and bone mineral density (BMD) is widespread in humans and has been adapted to animals because of the need to examine bone and body composition in longitudinal studies. In this review, the indications and techniques for DXA in small-sized animals (rodents, cats, and rabbits) and large-sized animals (dogs, swine, nonhuman primates, sheep, and horses) are discussed. Now that software has been developed for measuring BMD in small laboratory animals, the most frequent use of DXA in animals is in rats. An ultrahigh-re...
Couëtil L, Paradis MR, Knoll J.Pituitary adenomas are commonly reported in older horses. The typical clinical signs associated with this condition, also known as equine Cushing's disease (ECD), are related to increased adrenocorticotropin (ACTH) production resulting in hyperadrenocorticism. The primary purpose of this study was to determine whether plasma ACTH concentrations differed between cushingoid and healthy horses. The second objective was to determine the effects of blood sample handling techniques on ACTH concentrations. A commercial human ACTH radioimmunoassay (RIA) was used to quantify equine plasma ACTH. Intra-a...
Browning GF, Begg AP.Variant types of VP4 and VP7 gene segments of faecal rotaviruses from diarrhoeic foals were identified by restriction endonuclease digestion of reverse transcription/polymerase chain reaction (RT/PCR) products. The variants observed were correlated with serotypes by determination of the sequence of representative RT/PCR products (entire coding sequence for VP7 and the VP8 region of VP4) and comparison to published sequences of equine G and P serotype genes. Both G and P serotypes could be predicted for 95/116 (82%) strains, P serotype only for a further 8 (7%) strains and G serotype only for 1...
Isa P, Wood AR, Netherwood T, Ciarlet M, Imagawa H, Snodgrass DR.DIG-labelled ssRNA probes were prepared from variable regions of VP4 and VP7 cognate genes, and used in hybridization assays for P and G genotyping of group A cell culture-adapted equine rotaviruses and fecal samples collected from foals with and without diarrhea. The probes confirmed known P and G serotypes of sixteen cell culture-adapted strains. From one-hundred and twenty-one rotavirus-positive samples, 83 reacted when tested for their P and G genotype specific probes. From these, 71 were found to contain G3 P12 genotypes, and 11 G14 P12 genotypes. No sample reacted with H1 or L338 P and G...
Kojima K, Taniguchi K, Kobayashi N.We have sequenced gene 5 encoding NSP1 for three human, two porcine, two bovine, one feline, and five equine rotavirus strains, and compared the nucleotide and deduced amino acid sequences with the published sequences for other various strains. Subgroup I human strains L26, 69M, and DS-1 were found to have a similar NSP1 sequence despite their different G serotypes, VP4 genotypes, and RNA patterns. The NSP1 sequence of the human strain K8 showed a high degree of homology to those of porcine strains OSU and YM. A high degree of homology was found among three equine strains (H2, FI-14, and FI23)...
Bucci TJ, Hansen DK, LaBorde JB.Two of five pregnant rabbits gavaged with purified fumonisin B1 at 1.75 mg/kg/day died, one after 9 and one after 13 doses. Microscopic examination revealed focal small hemorrhages in cerebral white matter in both animals, with malacia and hemorrhage also present in the hippocampus of one. The lesions were bilateral. Both animals also had marked degeneration of renal tubule epithelium and of hepatocytes. Apoptosis was the dominant degenerative change in kidney and liver. Fumonisin is known to cause leukoencephalomalacia and hemorrhage in equines, but CNS changes associated with exposure to fum...
Le Bars J, Le Bars P.Successful investigation and prevention of mycotoxic problems requires close collaboration between scientists from several disciplines ranging from agronomists and technologists required during production of food and feeds, to toxicologists and pathologists examining the effects of mycotoxins on animals and man. Zootoxic metabolites following fungal infection result from four general mechanisms: (i) secondary fungal metabolism (mycotoxins, eg, aflatoxins); (ii) bioconversion of vegetal compounds (eg, dicoumarol); (iii) plant reactions (phytoalexins, eg, coumestrol); and (iv) plant-fungus assoc...
Balasuriya UB, Timoney PJ, McCollum WH, MacLachlan NJ.The variation and phylogenetic relationship of open reading frame 5 (ORF5) of 3 different laboratory strains of the original prototype Bucyrus strain of equine arteritis virus (EAV), the modified live virus vaccine (ARVAC, Fort Dodge Laboratories), and 18 field isolates of EAV from North America and Europe were determined by comparison of their gene sequences. The viruses differed from the published sequence by between 3 (99.6% homology) and 94 (87.8%) nucleotides and by between 3 (98.8%) and 24 (90.6%) amino acids. The field isolates differed from each other by between 2 (99.7%) and 110 (85.7...
van Essen GJ, Blom M, Fink Gremmels-Gehrmann J.To elaborate the diagnosis of rye-grass intoxication in a stallion demonstrating a neurotoxic syndrome characterized by ataxia and incoordination, a number of diagnostic tests were performed. Results of both, blood chemistry and haematology gave no indication for organ-specific or systemic lesions. Chemical analysis of the hay fed to the horse revealed the presence of the mycotoxin lolitrem B in concentrations consistent with those described in sheep and cattle with similar symptoms. Thus, it was concluded that the animals demonstrated the rye-grass-stagger(RGS)-syndrome.
Turner RM, Love CC, McDonnell SM, Sweeney RW, Twitchell ED, Habecker PL, Reilly LK, Pozor MA, Kenney RM.An 8-year-old stallion was evaluated because of recurrent urinary tract infections and chronic intermittent urospermia. After extensive diagnostic testing, it was hypothesized that the stallion had a reflex dyssynergia of the bladder and urethral sphincter. Initial attempts to manage the urospermia included semen fractionation, semen collection after voluntary urination, and use of semen extenders. None of these efforts reliably yielded a quality ejaculate. Administration of imipramine hydrochloride (1.2 mg/kg of body weight, PO, 4 hours prior to semen collection) was initiated in an attempt t...
Wiler R, Leber R, Moore BB, VanDyk LF, Perryman LE, Meek K.V(D)J rearrangement is the molecular mechanism by which an almost infinite array of specific immune receptors are generated. Defects in this process result in profound immunodeficiency as is the case in the C.B-17 SCID mouse or in RAG-1 (recombination-activating gene 1) or RAG-2 deficient mice. It has recently become clear that the V(D)J recombinase most likely consists of both lymphoid-specific factors and ubiquitously expressed components of the DNA double-strand break repair pathway. The deficit in SCID mice is in a factor that is required for both of these pathways. In this report, we show...
Doxey DL, Milne EM, Harter A.The outcome for 35 horses with chronic dysautonomia which were kept in the hospital at the Royal (Dick) School of Veterinary Studies and subsequently returned to their owners is recorded. They constituted 42.7 per cent of the 82 chronic cases seen between 1991 and 1994; the other 47 horses were euthanased while in hospital. Of the 35 animals returned to their owners four died and 27 were available for follow up; of these 27, 12 were working competitively and six were being trained for future competitive work. It takes at least a year before it is clear whether a horse can compete successfully ...
van der Kolk JH, Grinwis GC.A three-year-old pregnant Dutch Warmblood mare was referred to the Department of Large Animal Medicine and Nutrition, Faculty of Veterinary Medicine, because of weight loss for 1 month. The main clinical features were (beside weight loss) moderate ventral oedema, enlarged mesenteric lymph nodes, and uniform thickening of the wall of the jejunum. Haematological evaluation revealed leukocytosis (15.9 G.l-1 with 18% lymphocytes and 1% eosinophils) and a decreased total serum protein and albumin concentration (35 g.l-1 and 36.3% albumin). At necropsy transmural eosinophilic enteritis was found in ...
Lassen ED, Swardson CJ.In diseased animals, laboratory evaluations of erythrocytes, leukocytes, and hemostasis provide important information that contributes to either narrowing the list of potential diagnoses or to determining a specific diagnosis. To adequately interpret the results of these evaluations, normal erythrocyte and leukocyte kinetics and normal hemostatic function must be understood. In addition, knowledge of common diseases resulting in abnormalities of these laboratory tests and of typical changes in these tests caused by these diseases is vital. This article has reviewed normal erythrocyte and leuko...
Johnson PJ.Laboratory electrolyte and acid-base analyses are important for the characterization and assessment of the severity of disorders of fluid balance, and they enable the veterinarian to institute appropriate corrective therapeutic interventions. Abnormalities of electrolytes or acid-base rarely define the diagnosis, but certain diseases are characterized by predictable trends in these parameters. Important clinical situations in which assessment of electrolyte and acid-base status should be regarded as important to the equine practitioner include diarrhea, severe colic, peritonitis, pleuritis, dy...
Granstrom DE.This article reviews recent advances in laboratory diagnosis of equine parasitic diseases. Laboratory diagnosis of most equine parasitic diseases continues to rely on standard methods. Only laboratory diagnostic tests for EPM, cryptosporidiosis, and giardiasis were included. The criteria for testing and interpretation of results for each new diagnostic method were explained. Western blot and PCR testing for EPM and immunofluorescent staining with monoclonal antibodies for cryptosporidiosis and giardiasis were reviewed.
Madigan JE, Rikihisa Y, Palmer JE, DeRock E, Mott J.The original objective was to determine seroprevalence of Ehrlichia risticii antibody among horses in California. On the basis of the unexpected results of the survey, an investigation into the accuracy and reproducibility of results of the indirect fluorescent antibody (IFA) test for E risticii was carried out. Methods: Prospective, seroprevalence study. Methods: Healthy horses (n = 655) and horses with clinical signs of equine monocytic ehrlichiosis (EME; n = 514) from various regions of California. Methods: The IFA test was performed. Results were compared with results of an ELISA and with ...
Battelli G, Galuppi R, Pietrobelli M, Tampieri MP.Fecal examinations of horses (Equus caballus) from studs in the province of Udine (Friuli Venezia Giulia region, east-northern Italy), carried out during two periods of the year 1993, revealed coccidian oocysts in six foals, two stallions and one mare. The species was identified as Eimeria leuckarti. This species was reported only once in Italy, more than 20 years ago (1972). For this reason, the prevalence of the parasite and the description of immature and sporulated oocysts are given.
Fenger CK, Granstrom DE, Langemeier JL, Stamper S, Donahue JM, Patterson JS, Gajadhar AA, Marteniuk JV, Xiaomin Z, Dubey JP.Sarcocystis neurona is an apicomplexan that causes equine protozoal myeloencephalitis (EPM) in North and South America. Horses appear to be an aberrant host, because the merozoites continually divide in the central nervous system, without encysting. The natural host species has not previously been identified. The small subunit ribosomal RNA (SSURNA) gene of S. neurona was compared to those of Sarcocystis muris, Sarcocystis cruzi, Toxoplasma gondii, and Cryptosporidium parvum to identify a unique region suitable for a species-specific amplification primer. The S. neurona SSURNA primer was used ...
Barlough JE, Madigan JE, DeRock E, Dumler JS, Bakken JS.A Thoroughbred filly that developed clinical signs of equine granulocytic ehrlichiosis following inoculation with the human granulocytotropic ehrlichia was shown to be resistant to challenge with Ehrlichia equi, a closely related agent. This result further substantiates the close and potentially conspecific relationship between these two granulocytotropic ehrlichiae.
Wadsworth AB, Sickles GM.IT HAS BEEN SHOWN THAT THE PNEUMOCOCCUS MULTIPLYING IN THE TISSUES OF THE IMMUNIZED ANIMAL (HORSE) BECOMES ATTENUATED: loses, in varying degrees, its virulence, capacity of capsule formation, susceptibility to phagocytosis, and type specificity. The antigenic activity as an immunizing agent and the production of "soluble specific substance" are also altered. In some instances, the typical pneumococcus characteristics may be quickly restored by one or two passages through a susceptible animal (mouse). In others, virulence is not recovered and the organism remains atypical. Whether these changes...
This article provides an overview of initial assessment and management of common emergency presentations in donkeys and mules. The principles are similar to those in horses (and ponies), but clinicians must be aware of differences in recognition of signs of pain/disease, approach to handling, pharmacology of some drugs, and subtle differences in the physiology and local anatomy in donkeys and mules. The epidemiology of common disease presentations will vary between pet/companion or working/farmed donkeys and mules. Regular dental checks, deworming, vaccination, and monitoring of behavior and q...
Yvorchuk-St Jean KE, Debowes RM, Gift LJ, Kraft SL, Sinha AK, Kennedy GA.A 5-week-old belgian colt was examined for colic of 12 hours duration after several episodes of diarrhea. Physical examination revealed signs of abdominal pain, mild dehydration and normal auscultable borborygmi in all abdominal quadrants. Distention of the cecum, large colon and small intestinal was evident on abdominal radiographs. The foal was treated medically as the owners declined surgery. The colt was euthanized because of continued deterioration and failure to respond to medical therapy. Post-mortem exam revealed the presence of a trichophytobezoar obstructing the distal part of the tr...
Rhinosporidiosis is caused by Rhinosporidium seeberi, a parasitic organism of the family Rhinosporideacea family, class Micomycetozoa. The disease is endemic in India; however, some cases were reported in Europe, Africa, North America, and South America. The aim of the present study is to report three cases of rhinosporidiosis in wild horses in different cities of Buenos Aires province, Argentina. We confirm the presence of R. seeberi in the analyzed samples using histopathological and PCR sequencing techniques.
Binhazim AA, Harmon BG, Roberson EL, Boerner M.During routine necropsy of a 28-year-old horse with intestinal volvulus, numerous hydatid cysts were discovered in the liver. Viable protoscolices of Echinococcus granulosus were obtained from the cyst. As a 4-year-old, this horse had been imported from an area that is enzootic for equine hydatidosis.
Brownlie SE.The Chiltern Box is a small electrocardiograph designed for home monitoring of human patients. Its veterinary application has been investigated in the dog, the cat and the horse. It has been useful in the diagnosis of previously undiagnosed dysrhythmias in dogs showing signs of exercise intolerance and syncope.
Gatherer ME, Faulkner J, Voûte LC.The aim of this study was to compare the radiation doses received by the personnel drawing up and injecting the radiopharmaceutical and operating the nuclear scintigraphy equipment, and those restraining nine horses while they were being scanned during scintigraphic investigations of lameness. Sensitive electronic dosimeters were worn by the personnel and the doses they received during the administration of the radiopharmaceutical and during the period of image acquisition were recorded at intervals. On average, 90 per cent of the total doses were received during the period of image acquisitio...
Lecompte F, Combarnous Y.A simple, accurate, sensitive enzyme immunoassay (EIA) has been developed that permits the measurement of equine Chorionic Gonadotropin activity in pregnant mare plasmas or serums as well as in commercial and highly-purified preparations. This assay is specific for eCG and eLH which share the same polypeptide structure but differ in their oligosaccharidic chains. The more important result is that this EIA has been found to be give data in very close agreement with the in vivo assay. Therefore this very rapid and convenient assay can be used to measure the activity of eCG/PMSG in pregnant mares...
Gardner DG.Previously published cases of ameloblastoma in the horse are reviewed in detail for their acceptability as examples of that tumor; an additional one is described. So far, this rare equine lesion has been shown to have two histologic patterns. The first consists of islands and sheets of epithelium that exhibit the basal cell characteristics of ameloblastoma; the central cells comprise stellate reticulum. The second exhibits these basal cell features less markedly and the central cells are spindle-shaped and closely packed. The biologic behavior of the equine ameloblastoma is thought to be the s...
Okai K, Taharaguchi S, Orita Y, Yokota H, Taniyama H.To contribute to early diagnosis and treatment of gastric ulcer of foals, we examined the gastric mucosa of healthy and affected foals using an endoscope. In healthy foals, the characteristic changes in the development of the squamous mucosa were seen mainly in the squamous mucosa, and maturation of the squamous mucosa in the greater curvature (GC-S) occurred more slowly than that of the squamous mucosa in the lesser curvature (LC-S). Epithelial desquamation in the LC-S and GC-S was observed between 6 and 90 days but was not observed in the LC-S at about 60 days, whereas it was observed in the...
Eroksuz H, Eroksuz Y, Ozer H, Ceribasi AO, Yaman I, Ilhan N.Naturally occurring goiter cases are described in 2 newborn Arabian foals whose mares were supplemented with excess iodine during the final 24 w of the pregnancy. Six nursing foals and 2 mares were also affected clinically with thyroid hypertrophy. At least 12 times the maximum tolerable level of iodine supplementation was given, as the daily iodine intake for each mare was 299 mg. The prevalence of goiter cases was 2 and 9% in the mares and foals, respectively.
Cohen ND, Carey VJ, Donahue JG, Seahorn JL, Donahoe JK, Williams DM, Harrison LR.To identify factors associated with abortions of mares during late gestation attributed to mare reproductive loss syndrome (MRLS). Methods: Case-control study. Methods: 282 broodmares from 62 farms in central Kentucky, including 137 mares that had late-term abortions (LTAs) associated with MRLS, 98 mares from the same farms that did not abort, and 48 mares that aborted from causes other than MRLS. Methods: Farm managers were interviewed to obtain data on a wide range of management practices and environmental exposures for the mares. Data for case and control horses were compared to identify ri...
Loesch DA, Rodgerson DH, Haines GR, Watt BC.To report the postoperative outcome in horses undergoing jejunoileal anastomosis performed with a 2-layer simple continuous technique. Methods: Retrospective study. Methods: 7 horses. Methods: Information regarding signalment, clinical signs, findings at surgery, and postoperative complications was obtained from medical records of horses that underwent exploratory ventral midline celiotomy, small intestinal resection, and jejunoileal anastomosis to correct various small intestinal strangulating lesions. Follow-up information was obtained via telephone conversations with owners or trainers. Res...