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.
Acute leptospirosis in horses: A retrospective study of 11 cases (2015-2023). Reports of leptospirosis in horses are limited. Objective: To describe the clinical and diagnostic findings of acute systemic leptospirosis in horses. Methods: Eleven client-owned horses presented to an equine hospital because of acute onset of disease between 2015 and 2023. Methods: Retrospective case series. Horses diagnosed with leptospirosis by 1 or more of urine PCR, serologic microscopic agglutination test (MAT), and histopathology. Results: Common clinical signs included lethargy (10), anorexia (10), fever (9), tachypnea (9), abnormal lung sounds (9), and epistaxis (6). Acute kidney inj...
Explainable machine learning for assessing upper respiratory tract of racehorses from endoscopy videos. Laryngeal hemiplegia (LH) is a major upper respiratory tract (URT) complication in racehorses. Endoscopy imaging of horse throat is a gold standard for URT assessment. However, current manual assessment faces several challenges, stemming from the poor quality of endoscopy videos and subjectivity of manual grading. To overcome such limitations, we propose an explainable machine learning (ML)-based solution for efficient URT assessment. Specifically, a cascaded YOLOv8 architecture is utilized to segment the key semantic regions and landmarks per frame. Several spatiotemporal features are then ex...
Radiotherapy in Equine Practice. Radiotherapy is a valuable treatment option for equine tumors that have a high rate of recurrence or where complete surgical resection may damage vital structures. Teletherapy, brachytherapy, and plesiotherapy have been used successfully for the treatment of a variety of tumors and locations in the horse. Radiobiology, treatment protocols, side effects, and patient management are reviewed, with a focus on linear accelerator-based teletherapy. There is evidence of good success rates for treatment of periocular sarcoids and squamous cell carcinoma but teletherapy treatment is often limited to tu...
Equine Gastrointestinal Neoplasia. Gastrointestinal neoplasia is uncommon in horses. Clinical signs can be vague and advanced testing, including biopsy, exploratory surgery, and/or advanced imaging may be required for diagnosis. Prognosis varies by location, organ involved and is frequently poor to grave.
An updated description of bacterial pneumonia in adult horses and factors associated with death. Available descriptive studies on equine pneumonia are outdated or focus on specific horse or bacterial populations. Objective: To describe the clinical presentation and bacterial isolates of adult horses with bacterial pneumonia and identify factors associated with death. Methods: One hundred sixteen horses >2 years old with bacterial pneumonia. Methods: Retrospective case series. Data regarding history, physical examination, clinicopathologic features, treatment, bacterial culture and sensitivity, and outcome were collected and analyzed retrospectively. Results: Historical risk factors w...
Allergen-specific immunoglobulin-Es for dermatitis in the Japanese native Noma horses. Noma horses are native Japanese horses. Health checkups revealed that many Noma horses developed dermatitis during summer, which subsided in winter. Seasonal development and signs of itching, suggestive of allergic dermatitis, were observed. In this study, allergen-specific IgE was measured using blood samples collected from 15 Noma horses in summer and winter to identify allergens highly associated with dermatitis. The presence of dermatitis in the subject individuals was recorded during blood sample collection. White blood cell and eosinophil counts, serum total IgE concentration, and serum ...
Complete Blood Count and Biochemistry Reference Intervals for Healthy Adult Donkeys in the United States. Previous hematologic and serum biochemistry reference interval (RI) values have been established for donkeys in various geographic regions, life-stages, or for specific donkey breeds. The last extensive investigation establishing RIs for adult donkeys in the United States (U.S.) was published over three decades ago. We aimed to establish updated robust RIs using a reference population of apparently healthy adult donkeys from across the U.S. Standard sized ( = 102), miniature ( = 17), and mammoth ( = 1) donkeys from four different states were enrolled, with 20% of the study population including...
Characterisation of phenotypic patterns in equine exercise-associated myopathies. Equine exercise-associated myopathies are prevalent, clinically heterogeneous, generally idiopathic disorders characterised by episodes of myofibre damage that occur in association with exercise. Episodes are intermittent and vary within and between affected horses and across breeds. The aetiopathogenesis is often unclear; there might be multiple causes. Poor phenotypic characterisation hinders genetic and other disease analyses. Objective: The aim of this study was to characterise phenotypic patterns across exercise-associated myopathies in horses. Methods: Historical cross-sectional study, w...
Serum amino acid profiles in clinically normal Noma horses. Plasma or serum amino acids are used to evaluate nutritional status and metabolic disorders. In this study, we aimed to set reference values of serum amino acid concentrations in the Noma horse, a Japanese native horse. Thirty-one horses were classified into six age groups: neonatal foal (0-4 days), foal (0.5-1 years), youth (5 years), middle age (10 years), old (15 years), and extra-old (>20 years). Horses >5 years of age were analyzed together as the adult group. In the adult horses, there were no significant differences among the serum amino acid concentrations of each age group. The ...
Lyophilization as an alternative for conservation of equine plasma as a source of immunoglobulin G for neonatal foals. Providing plasma with immunoglobulins is essential for the health of foals with failure of passive transfer of immunity. The use of lyophilized plasma (LP) offers a simple and affordable option in terms of transportation and storage. This study aimed to measure the concentrations of immunoglobulin G (IgG), total protein (TP), and total solids (TS) in fresh equine plasma before and after lyophilization. Plasma was collected from six healthy male horses. The samples underwent freeze-drying and were reconstituted in deionized water to their original volume. The concentrations of IgG in both fresh...
PON1 enzyme activity assays for serum and heparinized plasma in horses and stability evaluation of the enzyme activity over different freeze-thaw cycles and mimic transportation. Consistent information and standardization procedures regarding the time of storage for frozen samples and the effects of storage time on enzyme activity are still missing in the literature. Thus, we evaluated the effects of different storage temperatures (-20 °C and - 80 °C), three repetitive freeze/thaw cycles, and 24-h mimic transportation on the activities of PON1 (paraoxonase and arylesterase), enzymes involved in the protection and detoxification processes of reactive molecules. PON1 enzymes' activity was validated on serum and heparinized plasma in horses. The results revealed tha...
Computed tomographic angiography of a presumed acquired transhepatic portosystemic shunt in a miniature horse filly. A 1-year-old Miniature Horse filly was presented for chronic lethargy and hyporexia. Elevated liver enzymes, bile acids, and ammonia were noted on bloodwork. The primary differential diagnosis was a portosystemic shunt (PSS). Three-phase computed tomographic angiography findings were consistent with a transhepatic portosystemic shunt. Percutaneous liver biopsy confirmed severe diffuse hepatic changes, most likely due to chronic pyrrolizidine alkaloid toxicosis, and medical management was elected. Based on an extensive literature review, this is the first report of a transhepatic portosystemic ...
Evaluation of vasovagal tonus index and electrocardiographic parameters in horses using a new modified base apex lead method. Vasovagal tonus index (VVTI) serves as a straightforward assessment tool for autonomic function during both physiological and pathological conditions, including pregnancy, in horses. Obtaining VVTI through a modified base apex lead system could be a practical and comfortable solution. In this study, we assessed VVTI in horses with respect to training status and electrocardiographic measurements utilizing a novel modified base apex lead technique. Unassigned: A total of 12 Thai native crossbred horses and 12 Arabian horses, all free of cardiac abnormalities, were enrolled in the study. Animals ...
Evaluating insulindysregulation in horses: A two-step insulin-tolerance test using porcine zinc insulin. In insulin dysregulation, hyperinsulinemia (HI) can be accompanied by peripheral insulin resistance (IR) in horses, which can be diagnosed with an insulin-tolerance test (ITT). The administration of 0.1 IU/kg body weight of recombinant regular human insulin (RHI) should elicit a 50 % reduction of the initial blood glucose concentration at 30 min after insulin administration in insulin sensitive horses. Compared to RHI, porcine zinc insulin (PZI) is veterinary-approved and therefore easier accessible for many practitioners. The aim of this study was to compare the insulin and glucose dynami...
Functional infrared thermography imaging can be used to assess the effectiveness of Maxicam Gel® in pre-emptively treating transient synovitis and lameness in horses. Diagnosing and treating lameness in horses is essential to improving their welfare. In equine orthopedic practice, infrared thermography (IRT) can indirectly detect soreness. Non-steroidal anti-inflammatory drugs can treat painful and inflammatory processes in horses. Using IRT, the efficacy of meloxicam (Maxicam Gel) was evaluated in pre-treating transient synovitis in horses induced by a middle carpal joint injection of lipopolysaccharides (LPS) from 055:B5 at a dose of 10 endotoxin units. Unassigned: In a cross-over design, six healthy horses were randomly assigned to receive either 0.6 ...
Inflammatory and Immune-Mediated Myopathies, What Do We Know? Inflammatory myopathies or myositis encompass diseases characterized by the presence of inflammatory cellular infiltrates, mainly polymorphonuclear cells and/or lymphocytes, in muscle. This is in contrast to most forms of muscle disease characterized by myodegeneration that results in macrophage infiltration. Inflammatory myopathies could have infectious or noninfectious causes. Noninfectious causes consist of primary (genetic, autoimmune) or acquired immune-mediated disease. Focal, multifocal or diffuse, acute or recurrent forms of disease can occur. This article will mainly review immune-med...
A multicentric intermediate-size B-cell lymphoma with epitheliotropism in a Freiberger mare. This report describes a multicentric intermediate-size B-cell lymphoma with epitheliotropism in a Freiberger mare affecting multiple mucous membranes, skin and internal organs. The clonal neoplastic B-cell population was accompanied by numerous reactive polyclonal small T cells. Differential diagnoses for these unusual findings are discussed. 本报告描述了一种多中心性中等大小B细胞淋巴瘤, 其在弗雷伯格母马中具有驱上皮性, 影响多处粘膜、皮肤和内脏。克隆性肿瘤B细胞群伴有大量反应性多克隆小T细胞。就这些异常发现对鉴别诊...
Measurement of Trace Elements (Zinc, Copper, Magnesium, and Iron) in the Saliva of Horses: Validation Data and Changes in Equine Gastric Ulcer Syndrome (EGUS). The objective of this study was to evaluate the possible use of spectrophotometric assays for the measurement of trace elements, including Zinc (Zn), Copper (Cu), Magnesium (Mg), and iron (Fe) in the saliva of horses and study their possible changes in equine gastric ulcer syndrome (EGUS). EGUS is a highly prevalent disease, with a current high incidence due to the increase in intensive management conditions. There are two EGUS diseases: equine squamous gastric disease (ESGD) and equine glandular gastric disease (EGGD), which can appear individually or together. For this purpose, automated spe...
Clinical Approach to Immune-Mediated Hemolytic Anemia and Thrombocytopenia. Primary immune mediated hemolytic anemia (IMHA) and thrombocytopenia (IMTP) are rare in horses with the conditions more commonly occurring secondary to underlying disease. Several case reports have suggested a link between neoplasia and immune-mediated destruction of platelets and red blood cells. Diagnostic investigations should therefore focus on identifying possible underlying causes such as infections and neoplasia. Immunosuppressive therapy with corticosteroids and azathioprine is the mainstay of treatment but should be used cautiously in cases where underlying infection has not been excl...
A case of equine multicentric lymphoma: Clinical, microscopical, and molecular findings. Although relatively uncommon, lymphoma is the most prevalent haematopoietic neoplasia in horses, and multicentric lymphoma remains the most common presentation of the disease. The pathogenesis of equine lymphoma is still poorly understood and the diagnosis is usually confirmed at an advanced stage of the disease, compromising the prognosis. This study investigated the clinical, pathological, and molecular features of a case of equine multicentric lymphoma. Unassigned: An apparently healthy 5-year-old crossbreed mare hospitalized at the Centre of Animal Reproduction of Vairão, Portugal, sudden...
Findings and Prognosis in 149 Horses with Histological Changes Compatible with Inflammatory Bowel Disease. Inflammatory bowel disease (IBD) is a chronic disease characterized by different cell infiltrates in the intestine. The aims of this study were to report the clinical and clinicopathological findings in horses with histological changes compatible with IBD in the duodenum. Further, the clinical progression of IBD and survival were investigated. Patient records were reviewed for horses in which histological evidence of IBD was found in duodenal biopsies collected during endoscopy. The histological changes were classified as mild, moderate or severe and the predominant infiltrating cell type was ...
ECEIM consensus statement on equine kidney disease. The aim of this consensus statement is to summarize and appraise scientific evidence and combine this with the clinical experience of a panel of experts to optimize recommendations on how to recognize and manage kidney disease in horses.
Bilateral bronchoalveolar lavage cytology profiles in a warmblood horse population during a 1-year period. Bronchoalveolar lavage (BAL) cytology results from 1 lung might not be representative of both lungs. Objective: To determine whether the lung site sampled would influence the horse's BAL cytology profile, and if a pooled BAL sample would be superior with regard to BAL cytology diagnosis in a cohort of healthy and subclinical asthmatic warmblood horses. Methods: Fifty-nine horses in 2021 and 70 horses in 2022, the follow-up included 53 of the same in each year. Methods: A cross-sectional study with follow-up included BAL cytology samples from individual lungs and from pooled BAL samples. The BA...
Immune-mediated Equine Vasculopathies. Immune-mediated vasculopathies occur secondary to infection or another noninfectious stimulus. Potential triggers include heterologous antigens including viruses, injected proteins and drugs; or auto-antigens including immunoglobulins or other endogenous proteins. Although these conditions are rare in horses, immune-mediated vasculopathies can cause considerable morbidity, with variable clinical signs depending on severity and organ system affected. Examples include purpura hemorrhagica, systemic lupus erythematosus, drug-induced vasculitis, paraneoplastic vasculitis, and idiopathic immune-med...
Approach to Inflammatory Bowel Disease. Inflammatory bowel disease (IBD) in the horse encompasses a group of infiltrative gastrointestinal disorders resulting in malabsorption, maldigestion, weight loss, colic, and sometimes diarrhea. The type of IBD can be classified as granulomatous, lymphocytic-plasmacytic, or eosinophilic enterocolitis. The diagnosis of IBD in equids is based on consistent clinical signs and clinicopathologic findings in conjunction with confirmatory histopathology from a gastrointestinal biopsy. Treatment usually consists of a combination of immunosuppressive medications, anthelmintics, and dietary modification...
Haematological reference intervals for pregnant Icelandic mares on pasture. Few studies have been conducted on haematological reference intervals (RIs) in Icelandic horses. Reference intervals have been published for Icelandic horses in Austria and a preliminary study in Iceland compared haematological values in riding horses to published RIs for other breeds as well as Icelandic horses abroad. Haematological parameters can vary greatly due to factors such as breed, gender, age, reproductive status, and training, as well as feeding, prior exercise and management method. Icelandic broodmares are kept on pasture under supervision throughout the year, with haylage provid...
Analytical Validation of MINI-PET as Point-of-Care for Erythrocyte Sedimentation Rate Measure in Horses. The erythrocyte sedimentation rate (ESR) is a widely used diagnostic assay in human medicine but nowadays poorly applied in veterinary medicine. This test measures the speed (millimeters per hour) at which red blood cells settle in a whole anticoagulated blood tube. In human medicine, high ESR values are associated with various disorders, including infections, rheumatoid arthritis, oncologic diseases, and other inflammatory conditions. The ESR can also be influenced by some factors such as age and gender. In veterinary medicine, the ESR with the Westergren manual method was almost forgotten ov...
Right dorsal colitis in horses: A multicenter retrospective study of 35 cases. Right dorsal colitis (RDC) is a nonsteroidal anti-inflammatory drug (NSAID) induced, protein losing enteropathy in horses associated with a high case fatality rate. Objective: To describe signalment, NSAID usage, clinical presentations, clinical pathology, ultrasonographic findings, treatments, outcomes, and factors associated with survival in horses diagnosed with RDC. Methods: Thirty-five horses from 7 Australian equine hospitals diagnosed with RDC. Methods: Retrospective case series. Clinical records of cases were accepted if definitively or presumptively diagnosed by an internist with RDC ...