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.
Weiss DJ, Trent AM, Johnston G.Prothrombotic changes occurring in the prodromal stages of carbohydrate-induced laminitis were investigated. Hemostatic alterations were evaluated by determining platelet counts, platelet survival, activated partial thromboplastin time, one-stage prothrombin time, and monocyte procoagulant activity. Thrombosis of vessels in the hoof wall was evaluated by contrast arteriography and histologic examination. Of 5 horses, 4 became lame between 28 and 52 hours after carbohydrate administration. Mean platelet count in laminitis-affected horses was lower throughout the prodromal stages of laminitis, c...
Austin SM, Foreman JH, Hungerford LL.Risk factors for development of pleuropneumonia were determined by reviewing medical records of 45 horses with pleuropneumonia and 180 control horses examined between Jan 1, 1980 and Jan 1, 1990. Factors considered included age, breed, sex, occupation, transport farther than 500 miles within the previous week, racing within the previous 48 hours, viral respiratory tract infection or exposure to horses with viral respiratory tract disease within the previous 2 weeks, and vaccination against influenza or rhinopneumonitis within the previous 6 months. Results indicated that Thoroughbreds were at ...
Church S.Three Quarter Horse stallions and 5 of their 11 tested progeny were diagnosed as affected with the inherited autosomal dominant defect hyperkalaemic periodic paralysis in Victoria in 1992. The diagnoses were based on the appearance of clinical signs and associated increased plasma potassium concentrations in response to oral potassium loading. All affected horses were descendants of the American Quarter Horse Impressive. Indirect evidence indicates that at least 3 other affected Quarter Horse stallions have stood or are standing at stud in Australia. The clinical details of the affected horses...
Kampl B, Dominis-Kramaric M, Bacar-Huskic L.The activities of leukocyte alkaline phosphatase (l-AP) and serum gamma-glutamil transferase (gamma-GT), and total leukocyte counts were determined in horses submitted to the production of hyper immune sera against tetanus (Clostridium tetani). The purpose of this work was to investigate the prospective changes of mentioned parameters in horses under the described circumstances. In addition, the suitability of these parameters in assessing the health condition of the same horses had to be evaluated. The average total leukocyte count increased in one month from the values considered as physiolo...
Guo Y, Wang M, Zheng GS, Li WK, Kawaoka Y, Webster RG.In May 1993, a severe epidemic of respiratory disease began in horses in Inner Mongolia and spread throughout horses in China. The disease affected mules and donkeys as well as horses but did not spread to other species, including humans. The severity of the disease raised the question of whether the outbreak might have been caused by the new avian-like influenza viruses detected in horses in China in 1989 or by current variants ofA/equine/Miami/1/63 (H3N8) (equine-2) or by a reassortant between these viruses. Antigenic and sequence analysis established that all gene segments of the influenza ...
Chirnside ED, de Vries AA, Mumford JA, Rottier PJ.Complementary DNAs encoding ORFs 2 to 7 equine arteritis virus (EAV) have been cloned into the expression vector pGEX to produce glutathione-S-transferase fusion proteins. Recombinant proteins were affinity purified and screened in ELISA with equine sera to identify immunoreactive polypeptides. The large envelope glycoprotein (GL) was identified as the most reactive to EAV-positive equine sera and an immuno-dominant epitope was mapped between amino acids 55 and 98 by subcloning and expression. A fusion protein covering this region and a GL-specific synthetic peptide (residues 75 through 97) in...
Lunn DP, Holmes MA, Schram B, Duffus WP.Equine immunoglobulin G is currently classified as consisting of five sub-isotypes: IgGa, b, and c, IgG(T), and IgG(B). The study of the role of these immunoglobulins in antigen-specific responses, and the examination of their functional properties would be greatly facilitated by the availability of monoclonal antibodies (Mabs) that distinguish between them. The production and characterization of two Mabs that recognize an IgG sub-isotype with the characteristics of IgG(ab) is described. The immunoglobulin identified by these Mabs had a heavy chain weight of 53 kDa, was of rapid cathodal elect...
Ochoa M, Bárcena J, de la Luna S, Melero JA, Douglas AR, Nieto A, Ortín J, Skehel JJ, Portela A.Characterization of the epitopes recognized by 21 monoclonal antibodies (MAbs) specific for the influenza A virus PA (13 MAbs) and PB2 (8 MAbs) polypeptides (Bárcena et al. (1994) J. Virol. 68, 6900-6909) raised against denatured polypeptides produced in E. coli is described. MAbs were characterized by: (1) competitive binding ELISAs; (2) mapping of the protein regions that specify their binding sites; and (3) analyses of their ability to recognize the corresponding viral protein in a number of viral isolates. Five and three non-overlapping antigenic areas were defined by the anti-PA and anti...
Campbell-Beggs CL, Johnson PJ, Wilson DA, Miller MA.A 12-hour-old female standardbred foal developed signs of abdominal pain, tachycardia, tachypnoea and fever associated with chylous ascites. Small intestinal obstruction was due to segmental, mid-jejunal lymphangiectasia. Post mortem examination revealed a lack of communication between afferent and efferent lymphatic vessels in the mesenteric lymphocentre, a defect which was suspected to be congenital.
Gliatto JM, Alroy J.A horse with malignant lymphoma (histiolymphocytic) and cutaneous amyloidosis is described. The lymphoma involved the dura mater of the spinal cord and some of the peripheral lymph nodes. Multifocal amyloid deposits were present in the skin and subcutis of the ventral abdomen but not within the lymphoma cell infiltrates or in the viscera.
Campagnolo ER, Trock SC, Hungerford LL, Shumaker TJ, Teclaw R, Miller RB, Nelson HA, Ross F, Reynolds DJ.Dermatitis consisting of blisters on the nose and other parts of the body was reported among horses at a Midwestern horse show. Some horses also had jaundice, hematuria and anorexia. An outbreak investigation was initiated, and of 239 horses for which information could be obtained, 58 (24%) were found to have been affected. Median duration of illness was 5 days, and all horses recovered. Age, sex, water source, grain source, and stabling location were not associated with illness. The use of wood shavings bedding obtained at the show grounds was the factor most strongly associated with the deve...
Steagall WK, Robek MD, Perry ST, Fuller FJ, Payne SL.The retrovirus equine infectious anemia virus (EIAV) encodes a dUTPase situated between reverse transcriptase and integrase. We have described the inability of EIAV with a 270-bp dUTPase deletion, delta DU EIAV, to replicate to wild-type (WT) levels in equine macrophages (D. S. Threadgill, W. K. Steagall, M. T. Flaherty, F. J. Fuller, S. T. Perry, K. E. Rushlow, S. F. J. LeGrice, and S. L. Payne, J. Virol. 67, 2592-2600, 1993). Here we describe the construction of a second dUTPase-deficient virus (DUD71E) containing a single amino acid substitution in dUTPase. delta DU and DUD71E replicate to ...
Carter SD, Osborne AC, May SA, Bennett D.To consider the hypothesis that autoimmune mechanisms may contribute to the pathology of equine joint diseases, 3 autoimmune responses were assayed in sera and synovial fluids. IgM-rheumatoid factor and antibodies to heat shock protein 65 kDa were determined by ELISA; anti-nuclear antibodies were assayed by indirect immunofluorescence to whole cell nuclear components. All parameters showed only modest increases, if any and not in a pattern related to disease, although some statistically significant increases were detected. Group analysis showed significantly elevated synovial fluid IgM-rheumat...
Wagner B, Radbruch A, Richards C, Leibold W.In order to define equine immunoglobulins (Igs) and to produce monoclonal reference Igs we fused equine peripheral blood mononuclear cells with X63-Ag8.653 non Ig producing murine myeloma cells. A total of 29 equine Ig producing equi-murine heterohybridomas were obtained, of which ten expressed equine Ig for more than 3 months. One of these heterohybridoma lines produced monoclonal IgM, an equine isotype which has not been available in monoclonal form before. Four lines secreted equine IgG of two distinct Ig heavy chain types as assessed by the molecular weight (MW), while the remaining five l...
Van Loon G, Deprez P, Muylle E, Sustronck B.Two horses were presented with complaints of chronic weight loss and subcutaneous oedema, one of them presenting diarrhoea. Both animals were grazed with other unaffected horses, all of them being regularly dewormed. Blood chemistry revealed hypoalbuminaemia and a low albumin-globulin ratio. Faecal egg counts were negative and no cyathostome larvae could be found in the faeces. Neither of these horses could be saved, despite intensive treatment. Postmortem examination revealed severe typhlitis and colitis due to numerous inhibited cyathostome larvae.
Madewell BR, Tang YJ, Jang S, Madigan JE, Hirsh DC, Gumerlock PH, Silva J.Intestinal colonization with toxigenic strains of Clostridium difficile was documented in 9 of 10 horses with acute onset diarrhea in a veterinary medical teaching hospital, whereas a similar isolate was detected in only 1 of 23 other horses without diarrhea in the hospital. One horse with diarrhea was infected simultaneously with both C. difficile and Salmonella krefeld. Clostridium difficile was detected by fecal culture on selective medium, confirmed with a latex particle agglutination test, and identified as toxigenic by polymerase chain reaction amplification of toxin A and toxin B gene s...
Milliken JE, Paccamonti DL, Shoemaker S, Green WH.A pseudohermaphrodite horse with aggressive stallion-like behavior and ambiguous external genitalia was gonadectomized. The hypoplastic gonads removed from the abdomen were confirmed by histologic examination to be testes. Examination of blood and fibroblasts revealed a 64,XX karyotype.
Bilzer T, Planz O, Lipkin WI, Stitz L.Tissues from 9 horses and 1 donkey suffering from natural Borna disease were investigated immunomorphologically. Lymphocytic inflammatory reactions and increased expressions of MHC class I and class II antigen were found in the brain as well as in the trigeminal and olfactory system. Perivascular inflammatory infiltrates were dominated by CD4+ T cells, whereas the majority of CD8+ T cells were disseminated intraparenchymally. No evidence of inflammation was found in the retina. Borna disease virus proteins and nucleic acids were present in the hippocampus, thalamus and medulla oblongata in all...
Madigan JE, Kortz G, Murphy C, Rodger L.Seven horses with headshaking are described. No physical abnormalities were detected in any of the cases. Six of these horses had onset of clinical signs in the spring. The role of light was assessed by application of a blindfold or dark grey lens to the eyes, covering the eyes with a face mask and observing the horse in total darkness outdoors. Cessation of headshaking was observed with blindfolding (5/5 horses), night darkness outdoors (4/4 horses) and use of grey lenses (2/3 horses). Outdoor behaviour suggested efforts to avoid light in 4/4 cases. The photic sneeze in man is suggested as a ...
Madigan JE, Valberg SJ, Ragle C, Moody JL.Severe muscle cramping not associated with exercise was observed in 5 horses. Focal muscle groups in various regions underwent intermittent visible contraction. Intermittent prolapse of the third eyelid, sweating, pawing, muscle tremors, and muscle fasciculations also were observed. Clinical signs often were misconstrued as signs of colic. Percussion of muscle induced contraction of muscle groups. Concentrations of serum electrolytes and the acid-base balance were within reference limits, but activities of creatine kinase and aspartate transaminase were moderately high. Muscle biopsy revealed ...
Chirnside ED, Francis PM, de Vries AA, Sinclair R, Mumford JA.A recombinant glutathione-S-transferase fusion protein expressing amino acids 55-98 of equine arteritis virus (EAV) GL (rGL 55-98) was tested in an ELISA for its ability to detect serum antibodies to EAV. Host antibodies induced following EAV infection bound the recombinant antigen by ELISA. The ELISA specificity and sensitivity were determined with a panel of equine sera including postinfection and postvaccination samples. A good correlation existed between EAV neutralizing antibody titers and ELISA absorbance values (r = 0.827). The sensitivity and specificity of the ELISA were 99.6 and 90.1...
Oikawa M, Takagi S, Anzai R, Yoshikawa H, Yoshikawa T.Eight young thoroughbred horses, taken 1858 km by road (travelling time, 41 h), were examined to assess the pathological nature of respiratory disease associated with transport. Three of the horses showed clinical abnormalities including pyrexia, coughing, leucocytosis and neutrophilia after the first 20 h of transportation. Endoscopical examination of the trachea revealed exacerbation of airway inflammation as a result of transport in two of the three affected horses. A consistent finding in the affected horses was focal serous neutrophilic pneumonia affecting the cranio-ventral portion of th...
Ayroud M, Leighton FA, Tessaro SV.Four of five reindeer (Rangifer tarandus tarandus) obtained from a Besnoitia sp.- infected herd at the Assiniboine Park Zoo in Winnipeg, Manitoba, Canada, in October 1989, had evidence of mild dermatitis over the articular surfaces of carpal and tarsal joints. Cysts of Besnoitia sp., either surrounded by inflammatory reactions or without evident host response, were present within the dermis, submucosa of the nasal turbinates, periosteum, tendons, testes and hooves. The light microscopic and histochemical features of Besnoitia sp. from reindeer were indistinguishable from those of other Besnoit...
Bernard WV, Cohen D, Bosler E, Zamos D.Blood samples obtained from 13 of 100 (13%) and 6 of 91 (7%) horses at the George D. Widener Hospital for Large Animals in the months of June and October, respectively, had antibody to Borrelia burgdorferi as determined by ELISA. Horses from the states of New York, Maryland, Delaware, New Jersey, and Pennsylvania were seropositive for B burgdorferi. The frequency of antibody response in horses from New Jersey was greater (P less than 0.05) than the frequency of antibody response in horses from Pennsylvania or that of horses from the other states combined. Statistically significant difference w...
Riggs MW.Currently recognized equine immune deficiency disorders include failure of passive colostral immunoglobulin transfer, combined immunodeficiency, selective IgM deficiency, transient hypogammaglobulinemia, and agammaglobulinemia. Additional equine immune deficiency disorders probably exist. Immune deficiency should be suspected in any horse experiencing persistent or recurrent infections that are not responsive to conventional therapy.
Barber SM.A case of uterine torsion in a mare with colic is described in which an early diagnosis was made and the torsion successfully reduced through a standing laparotomy with survival of both the mare and the foal. This case is used to stress the importance of thorough examination of all pregnant mares with colic in order to differentiate uterine torsion from other causes of abdominal pain, thereby avoiding delay in surgical correction and reducing the risk of fetal and/or maternal death. The advantages of the standing laparotomy are presented in support of this method of treatment of torsion of the...
Do Nascimento AG, Marchesan AL, Xavier BL, De Faria FR, De Almeida KM, Sato MO.The occurrence of nematodes in horses of Northern Region, State of Tocantins was studied. Fecal samples were collected from 70 horses and 31 donkeys, in a total of 101 animals of different ages, in the municipalities of Nova Olinda, Araguanã, Babaçulândia and Santa Tereza. Fecal examination was carried out for counting of eggs per gram of faeces, identification and quantification of larvae, diagnosis of habronemosis and lungworms. Significant occurrence of large and small strongyles and Dictyocaulus sp. was observed but no Habronema spp. larvae was detected.
Hillidge CJ.Idiopathic left-sided laryngeal paralysis was present in 14 of 169 horses on a thoroughbred horse farm (8.3 per cent). In nine animals, it was evident only after exercise and arytenoid abduction and adduction were normal at rest. Asynchronous movement of the arytenoid cartilages was observed in 94 horses at rest (55.6 per cent), 86 of which were considered to be normal after exercise. Conversely, synchronous movement of the arytenoids was noted when at rest in six of the 14 animals diagnosed as having laryngeal hemiplegia after exercise. An abnormal inspiratory noise during exercise was detect...
Sasani F, Javanbakht J, Ghamsari M, Hassan MA.We report one such case which was diagnosed intraoperatively as left dorsal colon volvulus due to multiple mesenteric abnormalities. A 17-year-old castrated male horse was taken to the Tehran University Veterinary Hospital for treatment of metacarpal wound accompanied by severe abdominal distension and acute colic. The treatment and measurement were taken for a month, and the prepared biopsy indicated that the healing trend was obvious. Unfortunately, prior to discharge, the clinical colic manifestations emerged and the animal suddenly died. Dilated large intestine was palpated per rectum and ...
Webbon PM.Skin temperature measurements were recorded of the legs of 13 racehorses between 2 and 5 years old. The normal limb temperature patterns are described. In over 90 per cent of the normal horses the difference between contralateral limbs was less than 1 degree C, but in the remainder differences of up to 8 degree C were recorded due to the excessive cooling of one limb. One horse had a constant temperature elevation of one foreleg, but it remained in training for 7 weeks without any obvious ill effects. Because of the small numbers of horses in the survey and their freedom from tendon injuries i...
Marryatt PA.Two subcutaneous masses were removed from the elbow of a mare. Histologically they were composed of islands of polygonal to plump spindlelioid cells with large nuclei, coarsely stippled chromatin, and eosinophilic cytoplasm. Findings were diagnostic for a malignant giant cell tumor of soft parts, a rare tumor with a fair prognosis.
Irfan M.Studies have been made on the effect of storage and temperature on factor V in animals and a method for its assay is described. There was a decrease of the factor with age in oxalated plasma of cattle, horses, sheep, dogs, rabbits and one elephant. This deterioration was very rapid in plasma kept at 37C. as compared with that stored at 4C. Rabbit plasma had the highest concentration of factor V followed by dogs, horses, cattle and sheep. Mixing various dilutions of aged plasma kept at 4C. wlth fresh plasma would enable the percentage prothrombin activity to be determined for the assay of facto...
Bailey KL, Kinsel MJ, Connell KA.Multiple cutaneous masses developed in the perineum of a 14-year-old Saddlebred stallion over a period of approximately 5 years. Clinically, the masses ranged in size from 3- to 9-mm diameter and were not ulcerated, painful, or pruritic. Three of the masses were surgically excised and submitted for microscopic evaluation. The masses were dome shaped to nodular, located in the superficial dermis, and composed of haphazardly arranged bundles of plump spindle-shaped cells. The tumor cells immunoreacted with monoclonal antibodies directed against desmin, muscle-specific actin, and smooth muscle ac...
MacLeay JM, Ames TR, Hayden DW, Tumas DB.This case report describes a 3-year-old American Quarter Horse with acquired immunodeficiency. Clinical signs included chronic diarrhea due to Salmonella typhimurium and bacterial pneumonia. Characterization of the immunodeficiency involved in vivo phytohemagglutinin (PHA) intradermal testing, in vitro lymphocyte proliferation in response to concanavalin A, immunofluorescence flow cytometry data on blood lymphocytes, serum protein electrophoresis and immunoglobulin (Ig) quantification. A diagnosis of B lymphocyte deficiency with resulting deficiencies in serum IgG, IgA and IgM and a concurrent...
Schumacher J, Dean P, Welch B.Unilateral epistaxis in 2 horses was caused by inflammation of the distal portion of the lacrimal system. The origin of epistaxis was identified during physical examination by observing hemorrhage emanating from the nasal opening of the nasolacrimal duct. Dacryohemorrhea caused by bacterial infection was successfully treated with antibacterial drugs administered systemically and instilled into the lacrimal system.