Topic:Clinical Pathology
Clinical pathology in horses involves the study and analysis of biological samples to diagnose and monitor diseases and health conditions. This discipline encompasses various laboratory tests and procedures that assess the physiological and biochemical status of equines. Common analyses include hematology, biochemistry, urinalysis, and cytology, each providing insights into different aspects of equine health. Hematology evaluates blood components, such as red and white blood cells and platelets, to identify conditions like anemia or infection. Biochemistry tests measure enzymes, electrolytes, and metabolites to assess organ function and metabolic status. Urinalysis examines urine samples for indicators of renal function and systemic diseases. Cytology involves the microscopic examination of cells from tissues or fluids to detect abnormalities. This page aggregates peer-reviewed research studies and scholarly articles that explore the methodologies, applications, and diagnostic value of clinical pathology in equine medicine.
Infection of young foals with Equine Parvovirus-Hepatitis following a fatal non-biologic case of Theiler’s disease. Theiler's disease (TD) is a (sub-)acute hepatitis in adult horses and one of the most common causes of acute hepatic failure. Recent findings indicate that equine parvovirus hepatitis (EqPV-H) likely causes TD and that its transmission occurs via iatrogenic and/or natural routes. Following the death of an EqPV-H positive mare with TD, close-contact mares and foals in the same paddock were monitored to evaluate if there was any evidence of EqPV-H. For this purpose, the serum of close contact horses was examined 6 and 42 days after the mare's death for the presence of EqPV-H DNA and changes in l...
Fetoplacental pathology of equine abortion, premature birth, and neonatal loss due to Chlamydia psittaci. This report describes the fetoplacental pathology of associated abortion, premature birth, and neonatal loss in 46 of 442 equine abortion investigations between 2015 and 2019. Seven abortions, 26 premature births, and 13 neonatal deaths with positive polymerase chain reaction (PCR) were evaluated. In 83% of cases (38/46), infection was considered as the primary cause of loss based on quantitative PCR (qPCR) confirmation, pathological findings, and exclusion of other causes, and was supported by immunolabeling in fetoplacental lesions. Lymphohistiocytic placentitis with vasculitis (36/38) af...
2D-SWE of the Metacarpophalangeal Joint Capsule in Horses. (1) Two-dimensional shear wave elastography (2D-SWE) employs an ultrasound impulse to produce transversely oriented shear waves, which travel through the surrounding tissue according to the stiffness of the tissue itself. The study aimed to assess the reliability of 2D-SWE for evaluating the elastosonographic appearance of the distal attachment of the fetlock joint capsule (DJC) in sound horses and in horses with osteoarthritis (OA) (2). According to a thorough evaluation of metacarpophalangeal joint (MCPJ), adult horses were divided in a sound Group (H) and in OA Group (P). Thereafter, a 2D-S...
Computed tomographic arthrography, gross anatomy and histology demonstrate a communication between synovial invaginations in the proximal aspect of the third interosseous muscle and the carpometacarpal joint in horses. This descriptive anatomical study investigates the relationship between the third interosseous muscle, also known as the suspensory ligament, and the carpometacarpal joint in forelimbs of horses, with the hypothesis that there was a direct synovial communication between these structures as shown by computed tomographic arthrography, histology, and gross anatomy sections. Computed tomography of the carpus and metacarpal region was performed on two groups. Group 1 consisted of eight cadaver limbs undergoing computed tomographic arthrography following injection of a mixture of positive contrast m...
Autopsies are required for all racehorses at most U.S. racetracks. No abstract available
Prevalence of Tumours and Tumour-like Lesions in Domestic and Exotic Animals from Lower Silesia and its Surrounds in Poland in 2014-2017. An analysis of samples originating from domestic and exotic animals from Lower Silesia but also from other parts of Poland was carried out based on research conducted in 2014-2017. Unassigned: The materials used for the study were 11,338 tumour samples taken in vivo during surgery and as biopsies and posthumously during necropsies. They were sent to the Department of Pathology at Wrocław University of Environmental and Life Sciences for histopathological diagnosis. Unassigned: The largest group were canine tumours, of which there were 9,745 (85.95%), followed by feline tumours, totalling 1,39...
Echocardiographic Features of the Ductus Arteriosus and the Foramen Ovale in a Hospital-Based Population of Neonatal Foals. The ductus arteriosus (DA) and foramen ovale (FO), including the septum primum (SP) and septum secundum (SS), are important structures in fetal circulation and are unexplored in neonatal equids. The objective of this study is to describe echocardiographic characteristics in a hospital-based population of neonatal foals. On days 2, 5 and 10 after parturition, cardiac ultrasound was performed, and clinical data were collected in healthy and diseased Warmblood foals. Fifty healthy ( = 15) and diseased ( = 35) Warmblood foals were examined. A left-sided and right-sided holosystolic murmur was audi...
Disseminated Hemangiosarcoma in a Mare Mule. An 8-year-old mare mule was presented with a facial mass and history of anorexia, unilateral epistaxis and purulent nasal discharge. The facial mass was encountered from the ventral to the lateral right canthus of the eye up to the facial crest. Thoracic ultrasonography showed five rounded masses. A standing CT under sedation was performed revealing a huge extension and infiltration on surrounding tissues. Due to the extension, type of lesions, outcome and suspicion of metastasis, the owner chose to euthanize the patient. Necropsy confirmed the presence of tumoral lesions spread into the lungs...
Transillumination Techniques for Vessel Identification During Small Colon Resection in Six Horses. Transillumination has been described in human surgery to improve vessel visualization but has not been described in horses. Since the equine mesocolon contains a great amount of fat which restricts visualization of the vessels, this technique could be useful during small colon resection. To describe transillumination of the mesocolon to provide an improved vessel identification during resection and anastomosis of the small colon in horses. Data of horses that underwent resection and anastomosis of small colon were recorded. Two transillumination techniques were used during resection and anasto...
Fetlock Joint Angle Pattern and Range of Motion Quantification Using Two Synchronized Wearable Inertial Sensors per Limb in Sound Horses and Horses with Single Limb Naturally Occurring Lameness. Fetlock joint angle (FJA) pattern is a sensitive indicator of lameness. The first aim of this study is to describe a network of inertial measurement units system (IMUs) for quantifying FJA simultaneously in all limbs. The second aim is to evaluate the accuracy of IMUs for quantifying the sagittal plane FJA overground in comparison to bi-dimensional (2-D) optical motion capture (OMC). 14 horses (7 free from lameness and 7 lame) were enrolled and analyzed with both systems at walk and trot on a firm surface. All enrolled horses were instrumented with 8 IMUs (a pair for each limb) positioned at t...
Hyponatremia in horses with septic pneumopathy. Hyponatremia is common in horses with bacterial pleuropneumonia, but no further characterization of this abnormality has been reported. Objective: Describe admission plasma sodium concentration ([Na]) in horses with septic pneumopathy and evaluate any association of plasma [Na] with markers of systemic inflammation. Methods: Medical records of horses >1Â month of age that between 2008 and 2021 had a transtracheal aspirate (TTA) performed, abnormal TTA cytology, positive TTA culture, pulmonary disease on ultrasonography, radiography or both, and plasma [Na] assessed by direct ion-selective-e...
Blood Transfusion in Equids-A Practical Approach and Review. Transfusion medicine is a crucial part of equine intensive and critical care. Blood transfusions can save lives in both acute and chronic cases of anemia, hemorrhage, and hemolysis. It is vital to have a comprehensive theoretical and practical understanding of the techniques, implications, risks, and complications. This review covers the physiology and pathophysiology of conditions requiring transfusion, as well as step by step guidance for practitioners of all experience levels. This review is designed to serve as a practical reference for those who are treating horses in either the field or ...
Dose-Dependent Hepacivirus Infection Reveals Linkage between Infectious Dose and Immune Response. More than 70 million people worldwide are still infected with the hepatitis C virus 30 years after its discovery, underscoring the need for a vaccine. To develop an effective prophylactic vaccine, detailed knowledge of the correlates of protection and an immunocompetent surrogate model are needed. In this study, we describe the minimum dose required for robust equine hepacivirus (EqHV) infection in equids and examined how this relates to duration of infection, seroconversion, and transcriptomic responses. To investigate mechanisms of hepaciviral persistence, immune response, and immune-media...
Clinical, Diagnostic and Histological Findings Involving Cheek Teeth Hypercementosis in Nine Horses. Hypercementosis is infrequently reported to affect the cheek teeth of horses and presents as mineral deposits either attached (peripheral) or solitary ovoid (nodular) structures in the tooth bearing region. There is overlap between radiological and histological appearance of hypercementosis, cementoma, and equine odontoclastic tooth resorption and hypercementosis (EOTRH). The clinical presentation, imaging features, surgical management, and histological findings of nine horses that presented for dental lesions and associated hypercementosis of cheek teeth are reported. Horses were 4-15 years o...
Effect of Acetylsalicylic Acid on Uterine Blood Flow, Gestation Length, Foal Birth Weight and Placental Weight in Pregnant Thoroughbred Mares – A Clinical Pilot Study. The aim of this double-blinded placebo-controlled study was to investigate the effect of acetylsalicylic acid (ASA) on uterine blood flow, gestation length, placental and foal weights in pregnant mares. Sixteen Thoroughbred mares of different age (13.3 ± 4.1) and parity (7.4 ± 3.1) were randomly assigned to three treatment groups. Mares in group C (n = 4) served as controls and received 5,000 mg lactose orally once daily from D 120 (D 0 = day of ovulation) until parturition. Mares in group ASA1 (n = 7) received 5,000 mg ASA orally once daily from D 120 until parturition. Mares in group...
Cardiovascular changes in horses with atrial fibrillation and high thyroid hormone concentration: a case-control study. Hyperthyroidism is a predisposing factor for atrial fibrillation (AF) in humans. The relationship between high thyroid hormone (TH) and AF in horses has not been evaluated. Objective: The aim of this study is to identify whether (1) high TH concentrations were present in horses with AF, (2) other cardiovascular effects were observed in horses with high TH and AF, and (3) TH status affected recurrence rate. Methods: Twenty-three horses presented with naturally occurring AF. Methods: Prospective case-control clinical study. Thyroid hormone concentration was measured in horses presenting with AF....
An objective study into the effects of an incline on naturally occurring lameness in horses. The clinical examination of lame horses in real world settings often requires the use of sloped surfaces. This pilot study aimed to evaluate the effects of uphill and downhill locomotion on asymmetry in horses with naturally occurring lameness affecting forelimbs and hindlimbs. Ten horses (8-19 years) with forelimb lameness and eight horses (7-16Â years) with hindlimb lameness were fitted with inertial sensors at the poll, withers, sacrum and both tuber coxae. Data were collected whilst the horses were trotted in hand on a level surface (20Â mm) among conditions in individual horses. Two horse...
Alterations to the synovial invaginations of the navicular bone are associated with pathology of both the navicular apparatus and distal interphalangeal joint when evaluated using high field MRI. Limited information exists regarding associations between distal interphalangeal joint (DIPJ) abnormalities and synovial invagination changes in the distal sesamoid (navicular) bone. This retrospective, analytical study aimed to measure specific characteristics of the synovial invaginations of the navicular bone to determine whether any single characteristic was associated with abnormalities in the DIPJ or navicular apparatus (NA) using high field MRI and a sample of 200 horses' feet. The DIPJ and NA were graded independently by three scorers. The grades were averaged, creating a global pathol...
Cannabinoid receptors are expressed in equine synovium and upregulated with synovitis. Osteoarthritis (OA) is a major cause of equine lameness. Cannabinoid (CB) receptors are now considered to be promising therapeutic targets in human rheumatology for pain and inflammation, however, little is known about the equine endocannabinoid system. Objective: The primary goal was to assess the presence and expression pattern of CB1 and CB2 in the synovium of healthy joints. A secondary goal was to explore the relationship between the CB expression, degree of synovitis and OA pathology. Methods: Ex vivo experimental study. Methods: Metacarpophalangeal joints (n = 25) from a tissue bank w...
Clostridial Diseases (Botulism and Tetanus). Botulism and tetanus are the 2 primary manifestations of neurologic disease caused by clostridial toxins. Only a small dose of clostridial toxin is required to induce severe, and often fatal, disease. Consequently, definitive diagnosis of either disease is nearly impossible to achieve antemortem or postmortem; presumptive diagnosis is usually made based on physical and neurologic examination findings. Because the severity of clinical signs can worsen rapidly, prognosis worsens when therapeutic intervention is delayed. Highly effective vaccines are available against both botulism and tetanus an...
Intravenous Magnesium Sulphate in Standing Horses: Effects on Physiological Parameters, Plasma Concentration of Magnesium and Nociceptive Threshold Tests☆. A bolus of 50 mg kg MgSO (treatment Mg) or the same volume of saline (treatment S) was infused over 15 minutes in 5 adult healthy horses. T0 was the end of the infusion. Physiological parameters were recorded throughout the study period. Measurements of electrical, thermal, and mechanical nociceptive thresholds were performed at the pelvic limbs at baseline (before T0), and at specific timepoints. Blood samples were taken at fixed timepoints before, during and until 12 hours after the infusion. For statistical analysis, the 95% confidence intervals (CI's) for the differences in nociceptive th...
Sex differences in cervical spinal cord and spinal canal development in Thoroughbred horses. Cervical vertebral stenotic myelopathy (CVSM), a common cause of cervical spinal cord compression, is a neurological disease characterized by general proprioceptive ataxia and weakness of hindlimbs that tends to develop in young adult Thoroughbred horses. Although male horses seem to be at increased risk for CVSM, the mechanism for the occurrence of sex differences in the prevalence of CVSM is still poorly understood. Hence, we hypothesized that sex differences in the development of cervical spinal cord and spinal canal would affect the development of CVSM. This study aimed to evaluate sex dif...
Clostridioides (Clostridium) difficile-associated disease, epiploic foramen entrapment, and gastric rupture in a Thoroughbred racehorse: case report and literature review. Epiploic foramen entrapment (EFE) is a common cause of small intestinal colic in horses and may lead to intestinal strangulation. Strangulating intestinal obstruction impairs the gastrointestinal outflow and can lead to secondary gastric rupture and endotoxemia. Clostridioides difficile can cause enterotyphlocolitis with colic in horses of all ages, and the process is commonly referred to as C. difficile-associated disease (CDAD). Here we report the results of the postmortem examination of a 7-y-old Thoroughbred racehorse with concurrent CDAD, EFE, and gastric rupture that was euthanized follo...
Nocardioform placentitis in a sample population of mares foaling in southeastern Pennsylvania and northeastern Maryland in 2020. Nocardioform placentitis (NP) has been associated with mid to late pregnancy loss in mares. To date, disease outbreaks have been described only in central Kentucky, although sporadic, isolated cases have been reported globally. This study describes a series of cases of NP that occurred in a sample population of 299 mares foaling in southeastern Pennsylvania and northeastern Maryland in 2020. These cases coincided with an outbreak of NP that occurred in Kentucky that same year. On farms that reported information on both normal and abnormal foalings, nocardioform organisms/DNA were isolated from...
Preliminary evaluation of the effects of a 1:1 inspiratory-to-expiratory ratio in anesthetized and ventilated horses. To describe some cardiorespiratory effects of an inspiratory-to-expiratory (IE) ratio of 1:1 compared with 1:3 in ventilated horses in dorsal recumbency. Methods: Randomized crossover experimental study. Methods: A total of eight anesthetized horses, with 444 (330-485) kg body weight [median (range)]. Methods: Horses were ventilated in dorsal recumbency with a tidal volume of 15 mL kg and a respiratory rate of 8 breaths minute, and IE ratios of 1:1 (IE1:1) and 1:3 (IE1:3) in random order, each for 25 minutes after applying a recruitment maneuver. Spirometry, arterial blood gases and dobutamine...
Serum immunoglobulin G concentration after plasma transfusion in neonatal foals with hypogammaglobulinemia in various health status. Due to the time-limited intestinal uptake of colostral immunoglobulins, the suggested treatment of hypogammaglobulinemia in new-born foals is usually plasma transfusion. The aims of this study were twofold: firstly, to investigate the course of serum IgG concentration after plasma transfusion in newborn foals; and secondly, to determine the amount of transfusion required for a significant increase in serum IgG concentration. For this purpose, the IgG concentration was measured in 23 foals at three different points in time: before transfusion, 1 hour after transfusion, and 24 hours after transf...
Plasma syndecan-1 concentration as a biomarker for endothelial glycocalyx degradation in septic adult horses. Limited information is available regarding endothelial glycocalyx degradation during sepsis in horses. Plasma syndecan-1 concentrations are increased in consequence of sepsis in other species and have been useful for prognostication. Objective: To determine whether plasma syndecan-1 levels are increased in adult horses affected with sepsis. Methods: Retrospective cohort study. Methods: Adult horses were assigned to one of three groups based on results of physical and laboratory examinations, clinical diagnosis, and results of previously described SIRS classification: Group 1 horses included he...
The Effect of Capacitive-Resistive Electrical Therapy on Neck Pain and Dysfunction in Horses. Neck pain and stiffness are increasingly recognized in horses and often treated using multimodal pharmaceutical and rehabilitation approaches. In humans, deep tissue heating is reported to reduce neck pain and increase flexibility. The objective of this project was to determine the effects of capacitive-resistive electrical therapy on neck pain and stiffness in horses. A blinded, randomized, controlled clinical trial with 10 horses assigned to active and 10 horses assigned to sham treatment groups. Neck pain, stiffness, and muscle hypertonicity were assessed by manual palpation. Forelimb postu...