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.
Rijkenhuizen AB, Németh F.The clinical signs, the radiographic appearance, and the treatment of two cases of fracture of the accessory carpal bone are described. The fractures were in the vertical plane. Surgical intervention consisted out of fixation of the fracture with two lag screws. Follow-up information revealed that one horse became sound and returned to complete athletic activity whereas the other horse remained lame. A brief literature review is given and the surgical treatment and the complications are discussed.
Weiss DJ, Geor RJ, Johnston G, Trent AM.The hypothesis that equine laminitis is caused by thrombosis of vessels in the laminar corium (dermis) was investigated. Hemostatic alterations were evaluated by determining platelet count, platelet survival, platelet adhesiveness to vascular subendothelium, activated clotting time, and whole blood recalcification time. Thrombosis of vessels in the hoof wall was evaluated by scintigraphic studies of the hoof wall after administration of indium-111 (111In)-labeled platelets, contrast arteriography, and histologic examination. Platelet count remained constant before and at the onset of lameness;...
Naylor JM.The purpose of this review is to present an up-to-date summary of the signs, diagnosis, treatment, and implications of equine hyperkalemic periodic paralysis. The review encompasses all original articles published between 1986 and early 1993. Hyperkalemic periodic paralysis is the result of a genetic mutation in the skeletal muscle sodium channel gene. It is inherited as an autosomal dominant trait; most affected horses are heterozygotes. The classical signs are muscle fasciculation, spasm, and weakness associated with hyperkalemia. However, these signs are only rarely observed in affected hor...
Forhead AJ, French J, Ikin P, Fowler JN, Dobson H.Hyperinsulinaemia is a commonly-observed characteristic of insulin resistance, and a reduction in insulin sensitivity is thought to be either a causative and/or symptomatic feature of equine hyperlipaemia. A positive correlation (r = 0.545, P = 0.0015) existed between plasma insulin and triglyceride concentrations determined in 31 donkeys with naturally occurring hyperlipidaemia/hyperlipaemia. Greater insulin values tended to occur in the animals with an overweight body score. Inter-animal variation in insulin concentrations, however, prevented the identification of any differences either with...
Leigh JA.A protein capable of activating bovine, equine and ovine plasminogen, but not that from human or porcine plasma, was purified from culture filtrates of Streptococcus uberis (strain 0140J). Purification was achieved by ammonium sulphate precipitation followed by molecular exclusion chromatography. The elution position of the native molecule was equivalent to a molecular mass of approximately 57 kDa. However, the molecular mass, as determined by SDS-PAGE, was 29 kDa, suggesting the existence of a dimeric structure. Purified immunoglobulin from three out of five monoclonal antibodies raised to th...
Kihurani DO, Nantulya VM, Mbiuki SM, Mogoa E, Nguhiu-Mwangi J, Mbithi PM.Equines are particularly susceptible to infection with Trypanosoma evansi and T. brucei, but rarely is natural T. congolense and T. vivax infection seen in horses. An outbreak of trypanosomosis occurred in a herd of horses used for patrolling the pineapple fields on the Del Monte Farm, Thika, Kenya initially involving 6 horses. On subsequent screening of the entire group, T. brucei, T. congolense and T. vivax infections were detected in 16 of the 35 horses. The tests used for diagnosis included microscopic examination of stained blood smears, buffy coat technique, mouse inoculation and antigen...
Mäkelä O, Gustavsson I, Hollmén T.Chromosomal analysis is not a routine examination in equine
practice. It is indicated, however, in infertile or subfertile
mares with small, inactive ovaries (Chandley et a/. 1975;
Power 1986).
The most commonly reported abnormalities in mares
concern sex chromosomes such as 63,XO and mosaic
63,XO/64,XX giving sterile mares and 64,XY resulting in
gonadal dysgenesis, sex reversal and testicular feminisation
(Power 1990). The phenotypic manifestations of a horse with
these karyotypic abnormalities are usually quite mild
compared with the corresponding abnormalities in man. These
mild ...
Böse R, Peymann B.From Babesia caballi in vitro cultures a preparation of 100% infected erythrocytes was obtained. From this, B. caballi antigens were extracted with the detergent 3-[(3-Cholamidopropyl)-dimethylammonio]-1-propane-sulfonate (CHAPS) and used as ELISA antigens. A control antigen of normal erythrocytes from the same donor horse was prepared in an identical manner. The ELISA and Western blot were validated by testing of sera from horses experimentally infected with B. caballi or B. equi or not infected with Babesia spp. ELISA and Western blot results were compared with those obtained by the immunofl...
Bowker RM, Rockershouser SJ, Linder K, Vex KB, Sonea IM, Caron JP.The innervation of the navicular bone (os sesamoideum distale) and its suspensory ligaments (ligamenta sesamoidea collateralia) (CSL) or proximal suspensory ligament and the ligamentum sesamoideum distale impar or the distal sesamoidean impar ligament (DS-impar ligament) was examined using combined anatomical techniques of silver impregnation and immunocytochemistry. Silver impregnation studies revealed an abundance of nerve fibres present in both the CSL and DS-impar ligament with the latter having relatively more nerve fibres. These silver-impregnated nerves coursed parallel to and were asso...
Hood DM, Grosenbaugh DA, Slater MR.Vascular perfusion casts were used to define and characterise the macroscopic perfusion defects present in the distal digit of 11 horses affected by chronic laminitis. Five clinically normal horses were used as controls. Based on clinical history and clinical status, horses with chronic laminitis were classified as being potentially treatable or clinically refractory. Eleven macroscopic vascular defects were noted in the casts from horses with laminitis. Four types of lesions were identified in the submural laminar circulation, 3 in the coronary bed and 4 were associated with the solar circula...
Willis P, Sekhar KN, Brooks P, Fayrer-Hosken RA.To characterize further the events involved in fertilization and early embryonic development in the mare, effect of the estrous cycle on oviductal fluid proteins was investigated. Five mares had indwelling cannulas placed in their oviducts so that fluid could be collected throughout the estrous cycle. Daily fluid volumes were recorded and mares were monitored for signs of standing estrus. Oviductal fluid samples were pooled across mares according to stage of cycle (either estrus or nonestrus) for further analysis. Two-dimensional polyacrylamide gel electrophoresis (PAGE) was used to determine ...
Monzon CM, Jara GA, Hoyos CB.The usefulness of the direct agglutination test (DA) to diagnose Mal de Caderas disease was evaluated. Forty four sera samples from two lots of horses with natural T. evansi infection (Lot 1 and Lot 2) were used. Thirteen (81.2%) of sixteen horses in which parasites were isolated gave positive agglutination titres (> or = 1:512) in the DA test. Treatment of these positive sera with 2-mercaptoethanol drops three to eight dilutions the agglutination titres in twelve samples (92%), showing the IgM nature of these antibodies. The DA test was also positive in seventeen of twenty eight horses in ...
Tulamo RM, Heiskanen T, Salonen M.High molecular weight (MW) hyaluronate (HA) is an integral part of synovial fluid (SF), regulating many important physiologic and pathophysiologic mechanisms. Many of its effects depend on, or are reflected in, the concentration and MW of HA. High-performance liquid chromatography was used to assess simultaneously the concentration and MW of HA in SF obtained from horses with various arthritides: acute traumatic arthritis; chronic traumatic arthritis, including degenerative joint disease (DJD); and infectious arthritis. The size-exclusion column was calibrated, using appropriate HA concentrati...
Steverink PJ, Salden HJ, Sturk A, Klein WR, van der Velden MA, Németh F.In this study the laboratory and clinical performance of a chromogenic endotoxin assay for equine plasma was evaluated. The assay was sensitive (detection limit 3 ng LPS/L plasma), reproducible (within and between-assay CV at 50 ng LPS/L E. coli O111:B4 LPS standard addition was 5% and 7.5%, respectively), and not substantially affected by enhancement or inhibition phenomena (recovery of an in vitro spike was 75-125% in 80% of the samples). LPS added to whole blood was rapidly inactivated upon incubation at 37 degrees C but not at 0 degrees C. A recently developed blood collection tube for LPS...
Stadler P, Deegen E, Kroker K.Echocardiographic evaluation of 45 horses (43 warm-blooded horses, one Thoroughbred and one Standardbred) with atrial fibrillation was performed, using M-mode, B-mode and pulsed-wave Doppler echocardiography. Seventeen (38%) of these horses had a history of poor performance. An increase of left ventricular shortening fraction was found in 25 horses (56%). Atrial dilatation was seen in 37 horses (82%). Eight horses (18%) had normal atrial dimensions. In nine horses only left atrium and in six horses only right atrium was enlarged. In the other 22 horses both atria were dilated. Correlation was ...
Johnson CB, Young SS, Taylor PM.The electroencephalogram (EEG) has been used in human clinical anaesthesia as an indicator of cortical activity and as an indicator of the depth of anaesthesia. It would be useful if it provided a reliable indication of the depth of anaesthesia of horses. In this study anaesthesia was induced with thiopentone and maintained with halothane in nine ponies. The end tidal halothane concentration (PE-Hal) was monitored and 20 seconds of EEG were recorded at 0.8 per cent, 1.0 per cent and 1.2 per cent halothane, equivalent to the minimum alveolar concentration (MAC), 1.25 MAC and 1.5 MAC. Each 20 se...
Lapointe JM, Vrins A, Lavoie JP.Bronchoalveolar lavages (BAL) were performed for 6 healthy horses and 8 horses with lower airway diseases (LAD). Total cell and differential counts were performed before and after centrifugation and resuspension of the BAL cells in a small volume of fluid; there was no difference in the total cell counts, but mast cell percentages were significantly (P < 0.05) lower, after centrifugation, in the LAD group. The two specimen preparation techniques compared were cytocentrifugation and centrifugation on microscope glass covers. For both groups of horses, lymphocyte percentages were significantl...
Baker SJ, Gerring EL.The gastric emptying of different forms of ingesta occurs by a variety of mechanisms and dysfunction may selectively affect different components of the gastric contents. A technique for assessing gastric emptying of solid, indigestible, radiopaque markers was developed. Emptying of these markers in four ponies was variable in both pattern and rate (half emptying time ranged from less than one hour to more than 24 hours). However, whereas in man physically similar markers appear to empty relatively rapidly when fasting but are delayed by a meal, no such delay was evident in these ponies. The ho...
Dyson S.Proximal suspensory desmitis of the hindlimb was diagnosed using local analgesic techniques and ultrasonography in 42 horses. Subtarsal analgesia resulted in substantial improvement in lameness in 36 of 41 horses in which local analgesic techniques were used. In the remaining five horses lameness was improved by perineural analgesia of the tibial nerve (three) or the tibial and fibular nerves. Intra-articular analgesia of the tarso-metatarsal joint produced a similar degree of improvement in two of 24 horses in which lameness had been improved by subtarsal analgesia. Ultrasonographic abnormali...
Connally BA, Derksen FJ.The usefulness of tidal breathing flow-volume loops (TBFVL) to evaluate pulmonary function was investigated in 6 Standardbreds during treadmill exercise. Tidal breathing flow-volume loops are a graphic representation of airflow rate vs tidal volume for each individual breath. These TBFVL were obtained from horses exercising at speeds corresponding to 75 and 100% of maximum heart rate. Measurements were recorded in each horse before and after ovalbumin-induced allergic lung disease. Moderate obstructive lung disease, characterized by a significant increase in pulmonary resistance, was observed ...
Wilson DV, Patterson JS, Stick JA, Provost PJ.The role of platelet-activating factor (PAF) in mediating the colonic damage that develops after large-colon torsion was studied in 14 ponies. Morphologic changes in areas of the ascending colon and selected abdominal and thoracic viscera after 1 hour of large-colon torsion and 3 to 5 hours of reperfusion were determined, as well as the protective effects of systemic administration of a specific PAF antagonist (WEB 2086). Ponies were selected then allocated at random and in equal numbers to 2 groups that received 1 of 2 treatments prior to induction of large-colon torsion: group 1--control (sa...
Stolk PW, Firth EC.Eight metatarsophalangeal (fetlock) joints were studied in anaesthetized young ponies. Pressure measurements were made in the joint and at various sites in the marrow cavity of the third metatarsal bone with simultaneous measurement of systemic arterial and venous blood pressures. Fetlock joint flexion was always associated with a statistically significant initial decrease in intra-articular pressure (p < 0.05) followed by a marked increase in pressure (p < 0.05). Subsequent extension was accompanied by a similar pressure pattern, although there appeared to be a hysteretic relationship. ...
Milne EM, Woodman MP, Doxey DL.Forty-five cases of chronic grass sickness were given scores for selected clinical measurements when they were first examined, to assess their value in predicting survival. Sixteen cases survived. The clinical scores for the degree of dysphagia, appetite, colic and the degree of reduction in gut sounds were significantly lower in the survivors than in the non-survivors. In addition, only the non-survivors had severe rhinitis. Ponies were significantly less likely to survive than cob types.
Jones SL, Langer DL, Sterner-Kock A, Snyder JR, Carlson GP.A 4-month-old male Trakehner foal with a history of hematuria, poor growth, and abnormal hair was found to have unilateral hydronephrosis and hydroureter, as determined by ultrasonography and surgical exploration. Nephrectomy and ureterectomy were performed as treatment. Gross examination of the ureter and kidney revealed renal pelvic and ureteral polyps causing obstruction and subsequent hydronephrosis. The histologic features were consistent with renal dysplasia. The polyps and renal dysplasia were likely to be congenital, but the etiopathogenesis is not known. The finding that urinary outfl...
Dodman NH, Normile JA, Shuster L, Rand W.Owners who believed they had a horse with self-mutilating behavior were asked to complete a questionnaire to obtain information on the signalment, clinical history, clinical signs, management, and treatment of the condition. Fifty-two owners of 59 horses responded; 2 cases were omitted because an organic cause was determined. Owners also were asked to complete information for unaffected horses on the same farm. Various breeds were affected, and of the 57 horses, 20 were stallions, 31 were geldings, and 6 were mares. Affected horses tended to develop the condition prior to sexual maturity. Clin...
Lyons ET, Tolliver SC, Stamper S, Drudge JH, Granstrom DE, Collins SS.Studies were conducted on transmission of natural infections of several species of internal parasites in horses born and kept on the same pasture on a farm in central Kentucky. Data for the first year (1989) of a 4 year study on this farm have been published recently. The present research represents the second (1990), third (1991), and fourth (1992) years of the investigation. The number of animals (n = 28) examined varied from eight born in 1990 to ten each born in 1991 and 1992. For each year, examination was made of one horse per month, beginning in June of the year of birth and extending t...
Bookbinder LC, Mani R, Carr EA.Contemporary data reflecting local pathogens and their antibiograms is necessary to select empirical antimicrobial therapy for equine neonates. Objective: Describe bacterial isolates associated with equine neonatal infection and their antibiograms in the Midwestern United States. An increase in gram-positive infection and antibiotic resistance compared to previous literature was expected. Methods: Data from 149 fluid samples from 133 foals <30 days of age submitted for bacterial culture between January 2007 and December 2018. Methods: A retrospective evaluation of equine neonatal fluid cu...
Watrous BJ.Head tilt in the horse is commonly a sign of either central or peripheral vestibular disease. The confirmation of vestibular disease is based on physical findings, including results of cranial-nerve function evaluation and observation of stance, posture, and gait. Further localization is made by ancillary tests such as cerebral spinal fluid analysis, electrodiagnostic testing, and radiography. The normal anatomy and physiology of the vestibular system, the abnormal clinical signs demonstrated during physical examination, and the various etiologies are discussed.
Turner TA, Fessler JF.Eleven horses with rectal prolapses were examined at Purdue University. Nine of the 11 prolapses were corrected by submucosal resection. Four of those were treated by a modified submucosal resection that apposes mucosa as well as submucosa. Follow-up of 8 cases, at intervals ranging from 4 months to 6 years, established that rectal prolapse did not recur following the resection.
Bayly WM, Grant BD, Breeze RG.Arterial blood gas and acid-base values during maximal exercise over a 1.2 km distance were recorded in four Thoroughbred horses before and after the chemical induction of pharyngeal lymphoid hyperplasia (PLH). Samples were collected after galloping 0.8 km and 1.2 km, immediately upon stopping and 5 mins after exercising. In only one horse was any difference noted in the pre and post PLH induction results. The horse was more hypercapnoeic at the 1.2 km mark and also took much longer to complete the gallop when it had PLH. However, it also had signs of lower respiratory disease. In the other ho...
El Sanousi SM, El Tayeb Amna B, Shadad EY.Uterine washes collected from 200 barren mares were examined at the Khartoum veterinary clinic during the period May 1977 to May 1978. A variety of bacteria was isolated from 77 per cent of the mares investigated. Thirty mares were treated by parenteral injection and intrauterine infusion of the appropriate antibiotics. Twenty-one of these mares conceived, of which 17 delivered normal foals and 4 had early embryonic deaths.
Spiro I.A 16-hour-old foal was referred for evaluation of hematuria. A pansystolic heart murmur and left thoracic thrill were detected; laboratory diagnostics and ultrasonography identified a complex congenital heart defect. The diagnosis was confirmed at postmortem.
Griss R, Simhofer H.Intraoral endoscopy is used as a standard diagnostic technique at the reporting clinics in horses presented with stomatological problems. Endoscopy of the oral cavity was performed using a chip camera, camera control unit, xenon cold light source and a rigid endoscope. In a three year period (2002 to 2004), second instars of Gasterophilus spp. were diagnosed in 14 warmblood horses 2 to 17 years of age. All horses were presented with masticatory problems or problems accepting the bit. In one horse oesophageal obstruction occurred in the course of larval migration. Oral endoscopy can not only be...
Koenig JB, Sawhney S, Cote N, LaMarre J.To determine whether inflammation of the jejunum of horses decreases the number of motilin receptors and amounts of motilin receptor mRNA and alters erythromycin lactobionate binding affinity to the motilin receptor in jejunal tissues. Methods: Jejunal segments in 6 adult horses. Methods: Each horse was anesthetized, and a ventral median celiotomy was performed; 2 segments of jejunum underwent a sham operation, 2 segments underwent ischemic strangulation obstruction (ISO), and 2 segments underwent intraluminal distension (ILD). Treatments were maintained for 120 minutes. From each segment, ful...
Lavach JD.The diseases included in this article constitute a wide range of maladies that affect the horse. Certainly, the diseases that are known today to produce ocular lesions are just a few of what will be discovered if attending veterinarians always examine the eyes of patients with systemic diseases.
Goetz TE.The structural and vascular anatomy of the healthy equine foot is compared with the pathologic changes in the foot of horses with acute and chronic laminitis. The structural and vascular abnormalities present in the foot of horses with laminitis are demonstrated in order to explain the abnormal manner in which their feet grow. The medical, surgical, dietary, and endocrine management of acute and chronic laminitis is discussed. Various forms of hoof trimming beneficial to the reestablishment of normal digital perfusion, normal hoof growth, and normal spatial orientation among the distal phalanx...
Williamson CC, Stoltsz WH, Mattheus A, Schiele GJ.The complement fixation test (CFT), indirect fluorescent antibody test (IFAT), card agglutination test for trypanosomiasis (CATT) and enzyme-linked immunosorbent assay (ELISA) were compared in their application to the serological diagnosis of Trypanosoma equiperdum infection in 43 horses. The CFT remains a reliable test for dourine, especially in countries where other members of the subgenus Trypanozoon do not occur. The IFAT is a good 'back-up' test, but, requiring skilled operators it has the disadvantage of making it labour intensive, and interpretation of results subjective. This makes it ...
Greenberg SM, Plummer CE, Brooks DE, Craft SL, Conway JA.An 8-year-old Gypsy Vanner gelding presented to the University of Florida Ophthalmology service for the evaluation of chronic, recurrent corneal ulcers behind the third eyelid of the right eye. On ophthalmic examination, a cluster of aberrant hairs was identified growing along the margin of the third eyelid. This portion of third eyelid was surgically excised, and histopathology identified the haired tissue as a dermoid. Chronic keratitis secondary to a third eyelid dermoid was diagnosed, and excision appeared curative at 6 months post-operative follow-up.
Sweeney CR, Stebbins KE, Schelling CG, Beech J, Schilling DA.Hypertrophic osteopathy was diagnosed in a pony that had no antemortem or postmortem evidence of an intrathoracic lesion. With a history of hirsutism in an aged pony, a pituitary adenoma was suspected, and evaluation of plasma cortisol and insulin values and their response to thyrotropin-releasing hormone supported the diagnosis.
Miller PJ, Holmes JR.Beat-to-beat variation in the amplitude of the QRS waveform from 13 horses with second degree partial atrioventricular block was examined using an orthogonal lead (X,Y,Z) system. The peak positive deflections (XR, YR and ZR) and peak negative deflections (XQS, YS and ZQ) were regressed against PR and RR intervals. XQS was used to indicate that the peak negative deflection in X could have been a Q or S wave. XR and YR were directly related to PR (P less than 0.001) and XQS and YS were inversely related to PR (P less than 0.001). YR was also directly related to RR (P less than 0.001) but not so ...
Lucchesi PM, Parma AE, Arroyo GH.Horses infected with Leptospira present several clinical disorders, one of them being recurrent uveitis. A common endpoint of equine recurrent uveitis is blindness. Serovar pomona has often been incriminated, although others have also been reported. An antigenic relationship between this bacterium and equine cornea has been described in previous studies. A leptospiral DNA fragment that encodes cross-reacting epitopes was previously cloned and expressed in Escherichia coli. Results: A region of that DNA fragment was subcloned and sequenced. Samples of leptospiral DNA from several sources were a...