Topic:Diagnostic Technique
Diagnostic techniques in equine medicine encompass a range of procedures and tools used to identify diseases, injuries, or other health conditions in horses. These techniques include imaging methods such as radiography, ultrasonography, and magnetic resonance imaging (MRI), as well as laboratory tests like blood work and tissue biopsies. Each diagnostic method provides specific information that can aid in the assessment and management of equine health issues. Radiography is commonly used for evaluating bone structures, while ultrasonography is useful for soft tissue examination. MRI offers detailed images of both soft and hard tissues, though its use is limited by cost and availability. Laboratory tests can detect biochemical and hematological changes indicative of disease. This page compiles peer-reviewed research studies and scholarly articles that explore the development, application, and efficacy of various diagnostic techniques in equine veterinary practice.
Computed Tomographic Tenography of the Equine Carpal Flexor Tendon Sheath. Exploratory tenoscopy is considered the gold standard technique to identify intrathecal pathology of the equine carpal flexor tendon sheath (CFTS). Preoperative diagnosis allows for more precise prognostication and surgical planning, potentially associated with improved surgical outcomes. This prospective, descriptive, anatomical study aimed to describe the anatomy of the equine CFTS using noncontrast and contrast CT in clinically normal cadaver limbs. Ten pairs of equine forelimbs free of gross external abnormalities were examined from mid-antebrachium to distal metacarpus. Specimens initiall...
Evaluation of an Automated Fluorescence Enzyme Immunoassay for Quantification of Equine Insulin and Comparison to Five Other Immunoassays. Hyperinsulinemia is an important and treatable risk factor for laminitis in horses. Objective: Evaluate the Tosoh AIA-360 automated fluorescence enzyme immunoassay for the measurement of serum insulin concentrations in horses, and compare it to five other immunoassays for insulin quantification. Methods: One hundred serum samples from 83 horses were submitted for insulin measurement. Methods: The Tosoh AIA-360 was assessed against a reference assay (radioactive immunoassay; RIA). Using the same samples, TOS-FEIA, ELISA, and three chemiluminescent immunoassays (CLIA) were assessed for correlati...
Diagnosis and treatment of a congenital cervical tracheal diverticulum in an Arabian foal. Tracheal congenital defects are infrequent but serious findings in animals. Tracheal diverticula are congenital air-filled cystic lesions, a sub-type of paratracheal air cyst mainly found extra-thoracically in foals. We describe a case in a twelve-day old show Arabian colt with right sided unilateral cervical swelling since birth. Percutaneous ultrasound revealed a heterogeneously air- and fluid-filled spheroid mass, and upper airway endoscopy confirmed luminal communication to the trachea. Contrasted computed tomography showed a narrow isthmus originating between two proximal tracheal rings a...
Detection of equid alphaherpesvirus 1 in serum samples collected from infected horses. Equid alphaherpesvirus 1 (EqAHV1; Orthoherpesviridae, Varicellovirus equidalpha1) spreads by viremia to susceptible organs. Because EqAHV1 circulates in the bloodstream in a cell-associated manner, serum samples are not considered valuable for detecting EqAHV1 and have therefore not been tested by highly sensitive detection methods such as real-time PCR (rtPCR). We investigated whether EqAHV1 could be detected by this method in equine serum samples. We performed rtPCR on archived sera and peripheral blood mononuclear cells (PBMCs) collected from 3 horses experimentally inoculated with EqAHV1. ...
Development and Validation of a Differentiating Infected from Vaccinated Animals (DIVA) Enzyme-Linked Immunosorbent Assay (ELISA) Strategy for Distinguishing Between Hendra-Infected and Vaccinated Horses. Hendra virus (HeV) is a bat-borne zoonotic agent which can cause a severe and highly fatal disease and can be transferred from animals to humans. It has caused over 100 deaths in horses since it was discovered in 1994. Four out of seven infected humans have died. Since the release of the HeV vaccine (Equivac® HeV Hendra Virus Vaccine for Horses, Zoetis Australia Pty Ltd., Rhodes, NSW 2138) in Australia, there has been an urgent requirement for a serological test for differentiating infected from vaccinated animals (DIVA). All first-line diagnostic serological assays at the Australian Centre f...
Detection and genetic characterization of equine viruses in Sweden using viral metagenomics. Viral infections pose a significant challenge to the equine population, compromising welfare and causing substantial economic losses for the global equine industry. While numerous equine viral pathogens have been identified, many suspected viral infections remain undiagnosed. This highlights the need for further identification and characterization of viruses circulating within the equine population. In this study, we utilized viral metagenomics to investigate viruses present in serum samples and nasal swabs collected from horses in Sweden. The primary focus was on horses presenting with fever,...
‘First record of Hsiungia pekingensis (Nematoda: Strongylidae) in North America: Morphological and molecular identification of a rare equine strongyle. Equids are infected by a diversity of gastrointestinal nematode parasites, including 64 species of equine strongyle nematodes from19 genera. Despite numerous surveys of horse strongyles worldwide, certain geographic regions and rare species remain understudied. In 1964, a new species of equine strongyle, Cylicocyclus pekingensis, was described from a donkey in China. Subsequently, this species was recorded in horses from Kazakhstan and reclassified as Hsiungia pekingensis (K'ung and Yang, 1964), the only species in this genus. Since then, H. pekingensis has not been reported elsewhere, with li...
Oxytocin in horse saliva: validation of a highly sensitive assay and a pilot report about changes in equine gastric ulcer syndrome. Equine gastric ulcer syndrome (EGUS) is a frequent disease in horses that comprises two different entities: equine squamous gastric disease (ESGD) and equine glandular gastric disease (EGGD). This disease considerably reduces the quality of life of affected horses and can negatively affect performance. Saliva contains biomarkers, such as oxytocin, that have been used as a welfare indicator and can develop a function as a protective factor against stress-induced changes in gastric function due to its gastric antisecretory and antiulcer effects. The objective of this work was to evaluate changes...
Investigation of the occurrence of low thyroxine concentrations and response to thyrotropin-releasing hormone using equine and canine assays in a population of Standardbred racehorses in Prince Edward Island, Canada. Decreased total T4 (tT4) concentrations are frequently observed in racing Standardbred horses lacking clinical evidence of hypothyroidism. This poses a diagnostic challenge as primary hypothyroidism is reported to be rare in adult horses. Despite this, owners frequently wish to administer thyroid supplementation to horses having low tT4 concentrations. Forty racing Standardbred horses were sampled. Baseline tT4 concentrations were determined using human-based (equine) and canine-based chemiluminescent assays. Dynamic evaluation of tT4 was performed using a thyrotropin-releasing hormone (TRH) s...
Tenoscopic-guided resection of the manica flexoria utilizing radiofrequency energy. A proof of concept study. To develop and optimize a tenoscopic technique for resection of the manica flexoria utilizing a radiofrequency probe. Methods: Experimental study. Methods: Eighteen cadaver limbs and two experimental horses. Methods: Tenoscopic-guided resection of the manica flexoria using radiofrequency energy proceeded sequentially by transection of the medial, lateral and proximal borders. The technique was performed in ex vivo limbs and then in vivo to replicate clinical scenarios. Time to complete resection of the manica flexoria (mean ± SD) and complications was recorded. Limbs were dissected and sc...
Measuring Noseband Tightness on the Lateral Aspect of the Horse’s Face. Measuring tools designed to objectively determine equine noseband tightness are inserted on the dorsal nasal planum in a rostro-caudal direction. The lateral aspect of the horse's head has several areas where minimal soft tissue intervenes between the skin and underlying bone, which makes them potentially useful sites for measuring noseband tightness. One hundred horses were fitted with a snaffle bridle with a cavesson, Swedish or dropped noseband in random order. The tightness of each noseband type was adjusted sequentially to 2.0, 1.5, 1.0, 0.5 and 0.0 finger-equivalents using an ISES Taper ...
Sensitization to Horse Allergens-Molecular Analysis Based on the Results of Multiparameter Tests. The domestic horse is the third most common source of animal allergens. Currently, five equine allergens have been classified (Equ c 1, 2, 3, 4, 6). Despite the apparently low exposure to allergens, equine allergy is still of great clinical importance. The aim of the study was to analyze equine allergy based on the results of ImmunoCAP ISAC and Allergy Xplorer ALEX tests. The study was retrospective. A total of 1553 patients were analyzed. Immunological tests were performed using the ImmunoCAP ISAC and Allergy Xplorer ALEX systems. From all the results, those with a positive result for at leas...
Investigation of the role of exercise in the detection of selected respiratory pathogens from nose wipes collected from healthy horses. This study aimed to determine if exercise increases the frequency of selected respiratory viruses/bacteria shedding in non-clinical horses using nose wipes. Nose wipes were taken pre- and post- exercise from 133 healthy horses of various ages and disciplines. Wipes were assayed for the presence of selected common (equine herpesvirus-1 (EHV), EHV-4, S. equi spp equi) and commensal (EHV-2, EHV-5, S. equi spp zooepidemicus) respiratory pathogens. The frequency of detection increased significantly (p < 0.05) in the post-exercise wipes for EHV-1, EHV-2, EHV-5, and S. zooepidemicus. EHV-4 and S. equ...
Time but not storage of equine plasma in silicate-coated tubes affects adrenocorticotropic hormone stability. Pituitary pars intermedia dysfunction (PPID) is diagnosed by measuring the ACTH concentrations. Due to the reported instability of ACTH, it is recommended to transfer centrifuged plasma into cryovials; however, in practice, cryovials are infrequently used, and serum (red-top) tubes are used instead. This study investigated whether this procedure affects ACTH concentrations and the diagnosis of PPID. Unassigned: This was a cohort study. Blood was collected into EDTA tubes from 9 horses with PPID and 7 controls. After centrifugation, plasma was either aliquoted into a cryovial or into a serum tu...
Can Arterial Blood Gas, Electrolyte and Acid-Base Analysis at Admission be Used to Predict Survival to Hospital Discharge for Different Causes of Colic? Predicting outcome in horses presenting with colic remains challenging. Objective: To test whether arterial blood samples in horses admitted for colic predict outcome to hospital discharge for different colic types. Methods: Arterial blood samples collected on admission from 358 horses undergoing medical or surgical management of colic were evaluated for pH, PaO, PaCO, Na, K, iCa, Cl, HCO (P), HCO (P, set), Base (B), Base (ecf) and anion gap. Categories were small intestinal non-strangulating (SINS) or strangulating (SIS) lesions, large colon non-volvulus (LCNV) or volvulus (LCV), small colo...
Needle tenoscopy of the digital flexor tendon sheath in a standing equine cadaver model using a novel approach and guided palmar/plantar annular ligament desmotomy. (1) To evaluate the feasibility of needle tenoscopy of the digital flexor tendon sheath (DFTS) using basisesamoid (BS) and proximolateral (PL) approaches in a standing equine cadaver model. (2) To report visualization of intrathecal DFTS anatomy via both approaches. (3) To determine the efficacy of needle scope-guided palmar/plantar annular ligament (PAL) desmotomy. (4) To report any iatrogenic damage associated with the procedure. Methods: Ex vivo experimental. Methods: Ten equine cadaver limbs. Methods: Limbs were placed in a Kimzey leg-saver splint and needle tenoscopy was performed using t...
Detection of Salmonella spp. in pooled environmental samples from an equine veterinary hospital using a novel point-of-care PCR assay. The objective of this study was to evaluate a point-of-care (POC) PCR assay for the detection of Salmonella spp. in pooled environmental samples collected at an equine veterinary hospital. A total of 945 environmental samples were collected from high-risk areas, including ICU and isolation stalls, high-traffic areas, treatment rooms, and surgical suites. The environmental samples were collected using drag swabs placed in selenite broth and individually incubated at 35 °C for 20 h. Following the incubation period, 1 mL of up to 10 individual environmental samples were pooled together. Each poo...
Prevalence of anti-N. caninum and anti-N. hughesi antibodies in horses and associated risk factors in two selected equine zones of Punjab, Pakistan. The aim of this study was to determine the prevalence of anti-Neospora (N.) caninum and anti-N. hughesi antibodies in horses and to appraise the associated risk factors in the two central districts (Jhang and Toba Tek Singh) of Punjab Province, Pakistan. A total of 300 horse sera were analyzed for the presence of antibodies to Neospora spp. using a competitive ELISA. The overall prevalence of antibodies against Neospora species in horses was 25 % (75/300; 95 % CI 20.1-29.9). The prevalence of antibodies to N. caninum and N. hughesi species was 12.3 % (37/300; 95 % CI 8.6-16) and 19.3 % (5...
Nonexertional Rhabdomyolysis. Although horses most commonly develop exertional rhabdomyolysis, there are numerous causes for nonexertional rhabdomyolysis (nonER) that pose a serious health threat to horses. Their etiologies can be broadly categorized as toxic, genetic, inflammatory/infectious, nutritional, and traumatic and a variety of diagnostic tests are available to discern among them. This study discusses causes of nonER as well as diagnostics and treatments that are specific to each etiology. General treatment of acute rhabdomyolysis is covered in detail in the study in this issue on sporadic and recurrent exertional...
Dickkopf-1 is present in equine platelet-rich plasma and correlates to platelet concentration. To determine if equine platelet-rich plasma (PRP) contains Dickkopf-1 (Dkk-1) and, if so, to quantify the amount of Dkk-1 in bovine thrombin (BT)-activated PRP and a control platelet lysate created using a freeze-thaw (FT) method. Unassigned: 10 adult horses were used in this experimental study. Blood was collected and processed in November 2019 and stored at -80 °C until the ELISAs were performed in October of 2023. Blood was collected from each horse, and PRP was created using a commercially available kit. Known concentrations of platelets were activated using BT or by an FT cycle to create...
Imaging flow cytometry reveals the mechanism of equine arteritis virus entry and internalization. The process of viral entry into host cells is crucial for the establishment of infection and the determination of viral pathogenicity. A comprehensive understanding of entry pathways is fundamental for the development of novel therapeutic strategies. Standard techniques for investigating viral entry include confocal microscopy and flow cytometry, both of which provide complementary qualitative and quantitative data. Imaging flow cytometry, which integrates the advantages of both methodologies, offers significant potential in virological studies. In this investigation, we employed imaging flow ...
Exploring a pico-well based scRNA-seq method (HIVE) for simplified processing of equine bronchoalveolar lavage cells. Single-cell RNA sequencing (scRNA-seq) is a valuable tool for investigating cellular heterogeneity in diseases such as equine asthma (EA). This study evaluates the HIVE™ scRNA-seq method, a pico-well-based technology, for processing bronchoalveolar lavage (BAL) cells from horses with EA. The HIVE method offers practical advantages, including compatibility with both field and clinical settings, as well as a gentle workflow suited for handling sensitive cells. Our results show that the major cell types in equine BAL were successfully identified; however, the proportions of T cells and macropha...
Prevalence of Theileria Equi and Babesia Caballi and Associated Hemato-Biochemical Changes in Racing Horses in Erbil Province, Iraq. This study aimed to determine the prevalence of Theileria equi (T. equi) and Babesia caballi (B. caballi) in racing horses in Erbil Province, Iraq, and to assess the associated hemato-biochemical changes in infected animals. Methods: A total of 196 horses, including 155 clinically healthy and 41 clinically suspected infected animals, were examined using Giemsa-stained blood films and PCR to determine the prevalence rates. Additionally, the hemato-biochemical parameters of infected horses were compared to a non-infected control group (n = 10). Results: The prevalence of T. equi and B. cabal...
Pulse oximetry at two sensor placement sites in conscious foals. Pulse oximetry has not been thoroughly evaluated for assessment of oxygenation in conscious foals. Compared with invasive arterial blood sampling, it is a painless and non-invasive method for real-time monitoring of blood oxygen saturation. The aim of this prospective clinical study was to evaluate the usability, validity, and reliability of pulse oximetry at two measuring sites (lip and caudal abdominal skin fold) for blood oxygen saturation measurement in conscious foals with and without respiratory compromise. Thirty-two foals under one month of age were used. Nineteen foals had normal resp...
Cartilage defect identification on computed tomography arthrography in equine fetlock: Ex-vivo study. CT arthrography (CTA) for evaluating cartilage defects would be beneficial in clinical practice. Since the contrast medium (CM) volume is often driven by operator experience, the aim was to evaluate the minimum volume of iodinated CM for CTA sufficient to identify iatrogenic cartilage defects in horse fetlock. The study was conducted on ex-vivo 32 distal limbs from adult horses collected at slaughter. Iatrogenic cartilage defects were arthroscopically made on fetlock, at 5 predetermined locations. Subsequently, CT scans were performed, according to the following protocol: precontrast scan, fol...
Yearling laryngeal function grades II.2 and below are not associated with reduced performance. The relationship between Thoroughbred yearling laryngeal function (YLF) grade and race performance is unclear. Objective: To determine the effect of YLF on future race performance. Methods: Retrospective cohort study. Methods: Post-sale endoscopic recordings were reviewed from Australian yearling sales in 2018-2019. Race performance was evaluated for career and as 2-, 3- and ≥4-year-olds. Multivariable generalised linear modelling examined the association between YLF and performance, with risk estimates presented as coefficients (95% CI). Results: The YLF in 5175 examinations was graded I in...
Detection of equine influenza virus gene in the air around infected horses. Equine influenza virus (EIV) can be transmitted by inhalation of aerosolized droplets, direct contact, and contaminated fomites. However, to our knowledge, there are no reports of the recovery of EIV from the air surrounding infected horses. Here, we evaluated whether EIV can be recovered from the air in the stalls of experimentally infected horses by using an air sampler. Furthermore, we examined whether rapid molecular test kits with reaction times of less than 30 min can detect EIV from air samples for potential field application. Two horses kept in individual stalls were experimentally i...
Changes in pressure distribution of the solar surface after a single trimming event are associated with external hoof measurements in the equine fore foot. Trimming is critical for a functioning equine hoof. Pressure distribution provides information on loading; however, information on the effects of trimming on pressure distribution is lacking. Objective: To describe the pressure changes of equine fore feet following trimming. Methods: Cross-sectional cohort study. Methods: Fifty sound horses were recruited. Eighteen external hoof measures of the dorsal, lateral, medial and solar aspects were obtained before and after trimming from 94 fore feet. Horses were walked over a pressure mat before and after trimming and pressure maps of the solar surfa...
Serum 25(OH) Vitamin D Concentrations in Horses: Effects of Age, Gender, Breed, Skin Colour and Season. The optimal amount of vitamin D required for the proper functioning of the immune system differs from the amount necessary for bone homeostasis. Furthermore, vitamin D metabolism varies among horses. Nevertheless, there is a dearth of information regarding reference values for vitamin D in horses, particularly in the Turkmen breed. The primary objectives of this study were to determine the concentrations of 25-hydroxyvitamin D (25(OH)Vit D) in Turkmen, Thoroughbred and mixed Turkmen × Thoroughbred horses and to explore the effects of various factors on it and its relationship with serum bio...
Evaluation of equine perineural anesthesia simulators with integrated success control for veterinary education. The skills necessary to perform diagnostic perineural anesthesia in equids belongs to one of the Day One Competences of a veterinarian, so every veterinary graduate should be able to perform them correctly. For logistical, hygienic and ethical reasons, practical exercises on cadaver limbs are not accessible to all students. Two equine distal limb simulators were developed and evaluated as an additional instructional tool to train the required skills. Both simulators were designed and built with an integrated success control, with Simulator I (S1) designed to be a simplified anatomical model an...