Ex vivo studies involve the examination of biological processes outside of a living organism, typically in a controlled laboratory environment. In equine research, ex vivo studies are used to investigate various physiological and pathological processes in tissues, cells, or organs derived from horses. These studies provide insights into cellular mechanisms, tissue responses, and the effects of various treatments or conditions without the complexities of a whole living system. Common applications in equine research include studying cartilage degradation, tendon repair, and immune responses. This page compiles peer-reviewed research studies and scholarly articles that explore the methodologies, findings, and implications of ex vivo studies in equine science.
Fratto MA, Hart KA, Norton NA, Barton MH, Giguère S, Hurley DJ.Cortisol is a key anti-inflammatory hormone that increases in bacterial sepsis and circulates predominantly bound to cortisol binding globulin (CBG). Only unbound cortisol was believed to be biologically active, but recent evidence suggests that CBG-bound cortisol also regulates inflammation. The objective of this study was to evaluate the effects of free and CBG-bound cortisol on equine neutrophil function ex vivo. We hypothesized that CBG would enhance cortisol-mediated suppression of neutrophil pro-inflammatory responses. Neutrophils isolated from 8 foals and 6 adult horses were exposed to ...
Stokol T, Serpa PBS, Zahid MN, Brooks MB.Equid herpes virus type-1 (EHV-1) is a major pathogen of horses, causing abortion storms and outbreaks of herpes virus myeloencephalopathy. These clinical syndromes are partly attributed to ischemic injury from thrombosis in placental and spinal vessels. The mechanism of thrombosis in affected horses is unknown. We have previously shown that EHV-1 activates platelets through virus-associated tissue factor-initiated thrombin generation. Activated platelets participate in thrombus formation by providing a surface to localize coagulation factor complexes that amplify and propagate thrombin genera...
Ziegler A, Everett H, Hamza E, Garbani M, Gerber V, Marti E, Steinbach F.Dendritic cells are professional antigen-presenting cells that play an essential role in the initiation and modulation of T cell responses. They have been studied widely for their potential clinical applications, but for clinical use to be successful, alternatives to xenogeneic substances like fetal bovine serum (FBS) in cell culture need to be found. Protocols for the generation of dendritic cells ex vivo from monocytes are well established for several species, including horses. Currently, the gold standard protocol for generating dendritic cells from monocytes across various species relies u...
Duesterdieck-Zellmer KF, Larson MK, Plant TK, Sundholm-Tepper A, Payton ME.OBJECTIVE To measure penetration efficiencies of low-level laser light energy through equine skin and to determine the fraction of laser energy absorbed by equine digital flexor tendons (superficial [SDFT] and deep [DDFT]). SAMPLE Samples of skin, SDFTs, and DDFTs from 1 metacarpal area of each of 19 equine cadavers. PROCEDURES A therapeutic laser with wavelength capabilities of 800 and 970 nm was used. The percentage of energy penetration for each wavelength was determined through skin before and after clipping and then shaving of hair, through shaved skin over SDFTs, and through shaved skin,...
Marlo TL, Giuliano EA, Sharma A, Mohan RR.To develop an ex vivo equine corneal organ culture model. Specifically, to assess the equine cornea's extracellular matrix and cellularity after 7 days using two different culture techniques: either (i) immersion system or (ii) air/liquid interface system, to determine the best ex vivo equine corneal model. Methods: Fourteen healthy equine corneas of various breeds. Methods: Equine corneas with 2 mm of perilimbal sclera were freshly harvested from 7 horses undergoing humane euthanasia. One corneal-scleral ring (CSR) from each horse was randomly placed in the (i) immersion condition organ cultu...
Veraa S, Bergmann W, van den Belt AJ, Wijnberg I, Back W.Diagnostic imaging is one of the pillars in the clinical workup of horses with clinical signs of cervical spinal disease. An improved awareness of morphologic variations in equine cervical vertebrae would be helpful for interpreting findings. The aim of this anatomic study was to describe CT variations in left-right symmetry and morphology of the cervical and cervicothoracic vertebrae in a sample of horses. Postmortem CT examinations of the cervical spine for horses without congenital growth disorders were prospectively and retrospectively recruited. A total of 78 horses (27 foals, 51 mature h...
Rütten S, Schusser GF, Abraham G, Schrödl W.Horses are much predisposed and susceptible to excessive and acute inflammatory responses that cause the recruitment and stimulation of polymorphnuclear granulocytes (PMN) together with peripheral blood mononuclear cells (PBMC) and the release of cytokines. The aim of the study is to develop easy, quick, cheap and reproducible methods for measuring tumor necrosis factor alpha (TNF-α) and interleukin-1 receptor antagonist (IL-1Ra) in the equine whole blood cultures ex-vivo time- and concentration-dependently. Results: Horse whole blood diluted to 10, 20 and 50 % was stimulated with lipopolysa...
De Lasalle J, Alexander K, Olive J, Laverty S.A better understanding of imaging characteristics of equine stifle osteoarthritis (OA) may allow earlier detection and improve prognosis. Objectives of this ex vivo, prospective, methods comparison study were to (1) describe the location and severity of naturally acquired OA lesions in the equine stifle using ultrasound (US), radiography (XR), computed tomography (CT), and macroscopic evaluation (ME); (2) compare the diagnostic performance of each imaging modality with ME; and (3) describe subchondral bone mineral density (BMD) in equine stifle joints with OA using CT. Radiographic, CT, and US...
Anderson SL, Singh B.Horses that develop colitis invariably exhibit signs of a systemic inflammatory response syndrome (SIRS). A significant contributor to the development of SIRS in human subjects is delayed neutrophil apoptosis, but this has not been specifically studied in horses. Objective: To determine the occurrence of ex vivo neutrophil apoptosis and its contribution to the development of SIRS in an equine colitis model. Methods: Experiment using a colitis model. Methods: Neutrophils were isolated before and after the induction of colitis using an oligofructose overdose model, placed into culture for 12 h o...
Markwell HJ, Mueller PO.To evaluate the properties of a ZipFix(®) (ZipFix) implant in equine laryngeal cartilages. Methods: Ex vivo biomechanical study. Methods: Equine arytenoid (n=36) and cricoid cartilages (n=18). Methods: Suture bites were placed in arytenoid or cricoid cartilages using a ZipFix(®) implant or a single strand of USP 5 braided polyester (TiCron™), and arytenoid and cricoid cartilages were separately subjected to single load to failure (25 N preload) or cyclic loading for 1,000 cycles, followed by single load to failure. Load, distraction, and stiffness were recorded. Results: Four arytenoid-Zip...
Wang XF, Lin YZ, Li Q, Liu Q, Zhao WW, Du C, Chen J, Wang X, Zhou JH.The equine infectious anemia virus (EIAV) vaccine is the only attenuated lentiviral vaccine applied on a large scale that has been shown to be effective in controlling the prevalence of EIA in China. This vaccine was developed by successive passaging of a field-isolated virulent strain in different hosts and cultivated cells. To explore the molecular basis for the phenotype alteration of this vaccine strain, we systematically analyzed its genomic evolution during vaccine development. Results: Sequence analysis revealed that the genetic distance between the wild-type strain and six representati...
Comino F, Giusto G, Caramello V, Pagliara E, Bellino C, Gandini M.In equine castration, application of a ligature on the spermatic cord to prevent complications such as haemorrhage and evisceration has been reported with controversial results. Characteristics of commonly used knots have not been studied. Objective: To compare the modified transfixing and giant knots and the emasculator in open and closed equine castration techniques. Methods: Ex vivo experiment. Methods: A total of 144 testicles were randomly assigned to 2 groups for open or closed castration. Both groups were divided into 3 subgroups of 18 specimens each: emasculator only, emasculator plus ...
Lescun TB, Hoffseth K, Yang HT, Hansma PK, Kopeikin HS, Chandrasekar S.To compare results obtained with a handheld reference point indentation instrument for bone material strength index (BMSi) measurements in the equine third metacarpal bone for various testing conditions. Methods: 24 third metacarpal bones. Methods: Third metacarpal bones from both forelimbs of 12 horses were obtained. The dorsal surface of each bone was divided into 6 testing regions. In vivo and ex vivo measurements of BMSi were obtained through the skin and on exposed bone, respectively, to determine effects of each testing condition. Difference plots were used to assess agreement between BM...
Reisinger N, Schaumberger S, Nagl V, Hessenberger S, Schatzmayr G.Laminitis is one of the most common diseases in horses. It is not only painful for the animal, but also has a significant financial impact on the equine industry. This multifactorial disease affects the connective tissue of the hoof. However, the pathogenesis of laminitis is still not fully understood. Endotoxins, also known as lipopolysaccharides (LPS), and bacterial exotoxins seem to play an important role during the development of laminitis. The aim of our study was to investigate the effect of increasing LPS concentrations (0, 2.5, 5, 10, and 100 μg/mL) on cell viability of isolated epide...
Bullone M, Beauchamp G, Godbout M, Martin JG, Lavoie JP.Endobronchial ultrasonography (EBUS) revealed differences in the thickness of the layer representing subepithelial tissues (L2) between human asthmatics and controls, but whether this measurement correlates with airway smooth muscle (ASM) remodeling in asthma is unknown. In this study, we sought to determine the ability of EBUS to predict histological ASM remodeling in normal and equine asthmatic airways. We studied 109 isolated bronchi from the lungs of 13 horses. They underwent EBUS examination using a 30 MHz radial probe before being processed for histology. ASM remodeling parameters were e...
Rubio-Martínez LM, Bracamonte JL, Tompkins S, Villarino NF.To describe a transthecal approach to the palmar pouch of the distal interphalangeal joint (DIPJ) in horses and compare it with the conventional blind arthroscopic technique. Methods: Ex vivo study. Methods: Cadaver forelimbs (n = 26 pairs) from mature horses. Methods: One limb from each pair was randomly assigned to each arthroscopic approach (conventional or transthecal). The conventional arthroscopic approach was performed as previously described and the transthecal approach was performed through sharp dissection of the distal reflection of the digital flexor tendon sheath (DFTS). The propo...
Norris JW, Pombo M, Shirley E, Blevins G, Tablin F.Two congenital bleeding diatheses have been identified in Thoroughbred horses: Glanzmann thrombasthenia (GT) and a second, novel diathesis associated with abnormal platelet function in response to collagen and thrombin stimulation. Objective: Platelet dysfunction in horses with this second thrombasthenia results from a secretory defect. Methods: Two affected and 6 clinically normal horses. Methods: Ex vivo study. Washed platelets were examined for (1) expression of the αIIb-β3 integrin; (2) fibrinogen binding capacity in response to ADP and thrombin; (3) secretion of dense and α-granules; (...
Goulet C, Olive J, Rossier Y, Beauchamp G.Early radiographic diagnosis of acute laminitis is important for treatment planning and prognosis in horses. While four histopathologic layers make up the hoof wall, only two layers are distinguished on digital radiographs of horses' hooves. Objectives of this descriptive study were to determine which macroscopic layers correspond to the two radiographically visible layers, and to describe radiographic layer measurements in a group of clinically sound Warmblood horses. Twelve ex vivo equine hooves were examined at three different levels of the dorsal hoof wall. The four macroscopic layers were...
Gallhoefer NS, Spiess BM, Guscetti F, Hilbe M, Hartnack S, Hafezi F, Pot SA.CXL penetration depth is an important variable influencing clinical treatment effect and safety. The purposes of this study were to determine the penetration depth of CXL in rabbit and equine corneas in epithelium-on and epithelium-off procedures and to assess an ex vivo fluorescent biomarker staining assay for objective assessment of CXL penetration depth. Methods: CXL treatment was performed according to a standardized protocol on 21 and 17 rabbit eyes and on 12 and 10 equine eyes with and without debridement, respectively. Control corneas were treated similarly, but not exposed to CXL. Hem...
Jones KE.The thoracolumbar region is clinically important in horses; however, the link between joint mobility and bony joint morphology has not been tested quantitatively. Objective: To establish which aspects of vertebral morphology correlate with ex vivo range of motion in the thoracolumbar region of Equus caballus, and demonstrate methodologies for linking vertebral form and function. Methods: Morphometric study of osteological specimens. Methods: A digital model was created of a disarticulated thoracolumbar region to examine bone-to-bone interactions during in silico bending. Linear measurements a...
Bindler D, Koch C, Gendron K, Ferguson SJ, Kaposi AD, Papp M, Bodó G.Mechanical evaluation of a novel screw position used for repair in a type III distal phalanx fracture model and assessment of solar canal penetration (SCP). Methods: Experimental study. Methods: Disarticulated equine hooves (n = 24) and 24 isolated distal phalanges. Methods: Hooves/distal phalanges cut in a sagittal plane were repaired with 1 of 2 different cortical screw placements in lag fashion. In group 1 (conventional screw placement), the screw was inserted halfway between the proximal border of the solar canal (SC) and the subchondral bone surface on a line parallel to the dorsal co...
McMaster MA, Munsterman AS, Weimar WH, Barrett EJ, Hanson RR.To compare the load to ultimate failure, load to a 2 mm gap, mode of failure, and gap at failure (mm) of the Teno Fix(®) (TF) to the 3-loop pulley (3LP) for repair of equine tendon lacerations. The use of 4TF devices versus 5TF devices on load to ultimate failure and load to a 2 mm gap was also compared. Methods: Ex vivo biomechanical study; unbalanced incomplete block (horse) design. Methods: Cadaveric equine forelimb superficial digital flexor tendon (n = 20 paired tendons). Methods: Ten tendon pairs were selected randomly and repaired with a 3LP and 4TF pattern, and 10 tendon pairs...
Aim of this study was to document the normal computed tomographic tenography findings of digital flexor tendon sheath. Six ex vivo normal equine forelimbs were used. An axial approach was used to inject 185 mg/mL of iopamidol in a total volume of 60 mL into the digital flexor tendon sheaths. Single-slice helical scans, with 5 mm thickness, spaced every 3 mm, for a pitch of 0.6, and with bone algorithm reconstruction, were performed before and after injections of contrast medium. To obtain better image quality for multiplanar reconstruction and 3D reformatting, postprocessing retrorecon...
Freeman KD, Barrett JG, Youngstrom DW, White NA.The 6-strand Savage (SSS) tenorrhaphy pattern is biomechanically superior to the commonly employed 3-loop pulley (3LP); however, its effects on intrinsic tendon vasculature remain unknown. The objective of this study was to compare perfusion of intrinsic vasculature of the equine superficial digital flexor tendon (SDFT) after 3LP and SSS tenorrhaphies. We hypothesized that the SSS technique would significantly decrease vascular perfusion compared to the 3LP technique. Methods: Ex vivo, randomized, paired design. Methods: Horses (n = 9) METHODS: Under general anesthesia, 9 pairs of forelimb...
Schnabel CL, Steinig P, Schuberth HJ, Koy M, Wagner B, Wittig B, Juhls C, Willenbrock S, Murua Escobar H, Jaehnig P, Feige K, Cavalleri JM.Leukocytes and their functional capacities are used extensively as biomarkers in immunological research. Commonly employed indicators concerning leukocytes are as follows: number, composition in blood, response to discrete stimuli, cytokine release, and morphometric characteristics. In order to employ leukocytes as biomarkers for disease and therapeutic monitoring, physiological variations and influencing factors on the parameters measured have to be considered. The aim of this report was to describe the ranges of selected leukocyte parameters in a sample of healthy horses and to analyse wheth...
Duz M, Parkin TD, Cullander RM, Marshall JF.To evaluate ex vivo cyclooxygenase (COX) inhibition and compare in vitro and ex vivo COX-1 inhibition by flunixin meglumine and firocoxib in horses. Methods: 4 healthy horses for in vitro experiments and 12 healthy horses (6 males and 6 females; 5 Thoroughbreds, 5 Warmbloods, and 2 ponies) undergoing elective surgery for ex vivo experiments. Methods: 12 horses received flunixin meglumine (1.1 mg/kg, IV, q 12 h) or firocoxib (0.09 mg/kg, IV, q 24 h). Blood samples were collected before (baseline) and 2 and 24 hours after NSAID administration. Prostanoids (thromboxane B2, prostaglandin E2, and p...
Rossi TM, Smith SA, McMichael MA, Wilkins PA.To evaluate the degree of activation of the contact pathway in citrated equine whole blood over holding times ≤ 30 minutes and assess effects of contact activation on recalcification-initiated thromboelastometry. Methods: 11 healthy adult mixed-breed horses. Methods: Blood was collected by atraumatic jugular venipuncture into prewarmed evacuated siliconized glass tubes containing citrate anticoagulant and held at 37°C for ≤ 30 minutes. Thromboelastometry was performed with an in vitro viscoelasticity (thromboelastometry) monitoring system. Factor XII and factor XI procoagulant activities ...
McCarty CA, Thomason JJ, Gordon K, Hurtig M, Bignell W.To add to the existing data on impact loading of the metacarpophalangeal (MCP) joint as a precursor to assessing the potential role of impact in joint disease. Objective: To examine the effect of impact loading on contact areas of the first phalanx (P1) and proximal sesamoids (PS) with the third metacarpal (McIII) under 3 hoof-strike conditions (toe-first, flat, heel-first). Methods: Randomised, repeated controlled experiment using cadaver material. Methods: Eight cadaver limbs were subjected to randomised, repeated controlled trials where the hoof was struck by a pendulum impact machine (impa...
Giusto G, Iotti B, Sammartano F, Valazza A, Gandini M.The aim of this study is to compare handsewn and stapled jejunocecal anastomosis with different stomal lengths in terms of anatomical differences. Group 1 underwent a two-layer handsewn jejunocecal side-to-side anastomosis (HS); Group 2 received a stapled jejunocecal side-to-side anastomosis (GIA). Each group was divided into two subgroups (HS80 and HS100, GIA80 and GIA100). Specimens were inflated and CT scanned. The stomal/jejunal area ratio and blind end pouch volume/area were measured and compared. Effective length of the stoma was measured and compared with the initial length. Stomal/jeju...
Bertuglia A, Mollo G, Bullone M, Riccio B.Longitudinal tears in the lateral aspect of the deep digital flexor tendon are the most common causes of pain localised to the equine digital flexor tendon sheath. However conventional ultrasonographic techniques provide limited information about acute lesions. Ultrasonographic contrast agents are newly developed materials that have contributed to advancement in human diagnostic imaging. They are currently approved for intravenous use in human and animal models. In this study we described intrathecal use in the horse. This study was undertaken to evaluate the reliability of standard and angle ...
Knych HK.Pharmacokinetics is the study of the movement of drug in the body and includes the processes of absorption, distribution, metabolism, and excretion. Pharmacodynamics is the pharmacologic effect of the drug on the body. The pharmacokinetics of a drug determines its pharmacologic effect. Pharmacokinetic studies describe drug concentrations while pharmacodynamics allow for assessment of drug effects. Combined pharmacokinetic/pharmacodynamic studies allow for integration of drug concentrations with pharmacologic effect. Data generated from pharmacokinetic studies can be especially useful in establ...
Baxter GM, Moore JN.Different dosages of aspirin were administered (by nasogastric tube) to 3 groups of 5 healthy adult horses to determine the minimal effective dosage needed to decrease serum thromboxane B2 (TxB2) concentrations and to determine the duration of this decrease. When compared with their base-line serum TxB2 concentrations, horses in group 1 (given 5 mg/kg) had a 71% decrease in TxB2 concentrations at 24 hours after aspirin was given and a 86% decrease at 48 hours; serum TxB2 concentrations were back to base-line values by 120 hours. Horses in group 2 (given 10 mg/kg) had a 60% decrease in TxB2 con...
Constant C, Zderic I, Arens D, Pugliese B, Gehweiler D, Gueorguiev-Rüegg B, Zeiter S.To determine the influence of screw head diameter on equine condylar fracture fixation with 5.5 mm cortical screws. Methods: Ex vivo, biomechanical study, blinded, matched-pair design. Methods: Fifteen pairs of equine third metacarpal (MC3) bones. Methods: Lateral condylar fractures were simulated by parasagittal osteotomies and repaired pairwise by 2 × 5.5 mm cortical screws of 8 mm (standard) or 10 mm (modified) head diameter. Interfragmentary compression at maximum screw insertion torque was measured. The instrumented specimens were pairwise stratified for biomechanical testing u...
Lenoir A, Perrin BRM, Lepage OM.Resection and anastomosis of small intestine during colic can lead to adhesions and recurrent colic. Several methods are available to reduce the rate of adhesions in the postoperative period, such as the use of serosal barriers. Surgical glues form a smooth surface, are fast to apply, and could reduce surgery time when performing anastomosis. A recently developed UV-polymerizable methacrylate adhesive (UV-PMA) is designed to anchor into the biological tissues' top surface offering sealant and a smooth cover over the anastomosis site. This adhesive was used ex vivo on fifteen samples of equine ...
Lean NE, Bertin FR, Ahern BJ.To assess the effect of vocal cordectomy on airflow across equine larynges at different Rakestraw grades of arytenoid abduction using a unidirectional airflow model. Methods: Ex vivo, repeated measures. Methods: Twenty cadaveric equine larynges. Methods: The right arytenoid cartilage was maximally abducted in all larynges. Each larynx was assigned a Rakestraw grade A or B, and the left arytenoid was abducted accordingly. Each larynx was tested under 3 conditions: intact, left vocal cordectomy (LVC), and bilateral vocal cordectomy (BVC). Translaryngeal pressure and airflow were measured, and di...
de la Torre J, Crespo F, Arroyo F, Zabal-Aguirre M, Abdoon AS, Gosálvez J.Artificial insemination programs for horses usually involve ex vivo handling and transporting of sperm. The present experiment was designed to: (i) assess the effect of transportation on sperm DNA integrity at different time post semen collection, and (ii) evaluate if sperm DNA quality deteriorates rapidly beyond 24 h of cooled storage. After collection, the ejaculates were extended using INRA 96 and semen was prepared for prompt analysis (A0) or 24 h/48 h cooled-shipping (B24 and C48 respectively). Each sample was assessed for sperm DNA fragmentation index (SDFI) at time 0 and after inc...
Gandini M, Iotti BN, Giusto G.To compare 4 techniques for pelvic flexure enterotomy closure in horses. Methods: Ex-vivo study. Methods: Cadaveric ascending colon specimens (n = 48 horses). Methods: Pelvic flexure enterotomies of different lengths (5 cm, 10 cm) were performed and closed with 1 of 4 techniques: handsewn 2 layer (HS2); handsewn 1 layer (HS1); skin staples (SKS); or TA90 stapling device (TA90). Time to close each enterotomy, bursting pressure, luminal reduction, and cost were calculated and compared. Results: HS2 was significantly more time consuming to perform in the 5 cm group whereas in the 10 cm group, onl...
Genton M, Robert C, Jerbi H, Huet H, Cordonnier N, Vitte-Rossignol A, Perkins JD, Rossignol F.To describe the innervation of the thyrohyoideus (TH) muscle and to confirm our findings with stimulation of first cervical (C1) nerve branches. Methods: Ex vivo phase 1 and clinical phase 2. Methods: Fourteen head and neck specimens and 17 client-owned horses. Methods: In phase 1, the cranial nerve (CN) XII and the C1 nerve were dissected with their branches in 20 dissections were performed on 14 specimens (6 left and right side and 8 only left or right) Anatomy was noted. Samples of nerve bifurcations were collected for histological confirmation of anatomical findings. First cervical nerve b...
Vandeweerd JM, Perrin R, Launois T, Brogniez L, Clegg PD, Desbrosse FG.To compare the precision of radiography and computed tomography (CT) preoperatively in the standing position for identification of guidelines for screw insertion in the distal phalanx, and to identify whether standing CT might improve operative time compared with preoperative radiographic planning. Methods: Experimental ex vivo study. Methods: Cadaveric equine thoracic limb pairs (n=10). Methods: Insertion of a 4.5 mm cortex screw in lag fashion into an intact distal phalanx was evaluated in 2 groups (n=10) of cadaveric equine thoracic limbs. In 1 group, the site, direction, and length of the ...
Guan F, Uboh CE, Soma LR, You Y, Li X, McDonnell S.19-Norandrostenedione (NAED) and nandrolone are anabolic-androgenic steroids (AASs). Nandrolone was regarded solely as a synthetic AAS until the 1980s when trace concentrations of apparently endogenous nandrolone were detected in urine samples obtained from intact male horses (stallions). Since then, its endogenous origin has been reported in boars and bulls; endogenous NAED and nandrolone have been identified in plasma and urine samples collected from stallions. More recently, however, it was suggested that NAED and nandrolone detected in urine samples from stallions are primarily artifacts d...
Diana A, Freccero F, Giancola F, Linta N, Pietra M, Luca V, Salamanca G, Cipone M, Chiocchetti R.Ultrasonographic morphometry of wall layers is commonly used in veterinary patients with suspected small intestinal disease, however published studies comparing this method with histopathology in horses are limited. This prospective, methods comparison study compared the qualitative and quantitative characteristics of small intestinal wall layers using ex vivo high-frequency ultrasound versus histopathology in a sample of 16 horses. Transverse section images of duodenum, distal jejunum, and ileum were acquired with a high-frequency linear transducer (7-15 MHz). Transverse histological cryosec...
Zetterström SM, Boone LH, Farag R, Weimar WH, Caldwell FJ.To evaluate a double hemitenotomy (DHT) technique as an alternative to complete deep digital flexor (DDFT) tenotomy. Methods: Experimental ex vivo study. Methods: Isolated DDFTs (n = 30) and cadaveric forelimbs (n = 16). Methods: In part 1, 15 isolated DDFT pairs were used. Two hemitenotomies were created in 1 DDFT while the other served as reference. Monotonic tensile load was applied. Tendon lengthening, load reduction, and load at failure were recorded. In part 2, 16 cadaveric forelimb pairs were subjected to DHT followed by complete tenotomy (CT) under monotonic compressive load. Diffe...
Anne-Archard N, Martel G, Fogarty U, Richard H, Beauchamp G, Laverty S.The aetiology of equine metacarpal condylar fractures is not completely understood and a developmental cause has been postulated. Objective: To investigate the subchondral bone trabecular microarchitecture of the lateral parasagittal groove and condyle in equine neonates and its adaptation with maturation and athletic activity. Methods: Ex vivo observational study. Methods: Distal metacarpi of neonates, yearlings and adult racehorses (n = 24) were harvested. Dorsal and palmar frontal histological sections, containing the lateral parasagittal groove and condyle, were studied. The sections were ...
de Souza AF, Pascual CJ, Maia BT, do Valle De Zoppa AL.This study aimed to evaluate the distribution of dye at two perineural injection sites of the palmar/plantar nerves and describe their anatomical variations of positioning at the level of the distal metacarpus/metatarsus in horses. Two ml of 1% methylene blue solution was injected in 24 limbs (12 forelimbs and 12 hindlimbs) of horse cadavers at two different points: Group 1: between the branch of the suspensory ligament and deep digital flexor tendon, and Group 2: between the deep and superficial digital flexor tendons. This was followed by dissection and evaluation of the solution diffusion. ...
Smith RL, Murphy DJ, Day RE, Lester GD.To test single cycle to failure tensile strength characteristics of 6 suture material-pattern combinations in equine superficial digital flexor (SDF) tenorrhaphy, specifically to compare a 10-strand modification of the Savage core suture technique with the 3-loop pulley technique. Methods: Ex vivo mechanical experiment comparing 3 different suture patterns with 2 different materials. Methods: Forelimb and hindlimb SDF tendons (n=48) harvested from adult Thoroughbred and Standardbred horses of mixed age and gender. Methods: Six suture material-pattern combinations were evaluated: (1) 10-strand ...
Clemmons RM, Lee MR, Bliss EL, Asbury AC, Cook D, Brown V.Superoxide dismutase (SOD), a free radical scavenger with anti-inflammatory activity, was administered IM to horses. Ex vivo platelet aggregation in response to arachidonic acid was monitored to determine whether exogenous SOD altered equine platelet prostaglandin metabolism. Preparations of platelet-rich plasma obtained before SOD administration were incubated with different concentrations of SOD and were aggregated with arachidonic acid. Superoxide dismutase did not exert a demonstrable effect, either ex vivo or in vitro. Aspirin abolished arachidonic acid-induced platelet aggregation in vit...
Munsterman AS, VanderBroek AR, Kottwitz JJ, Watson VE.To compare a novel suture loop method for intestinal biopsies (SLB) with a two-layer, hand-sutured biopsy (HSB) technique in equine small and large intestines. Methods: Experimental, randomized, ex vivo study. Methods: Eight healthy adult horses. Methods: The duodenum, aboral jejunum, and ventral and dorsal large colon were harvested after euthanasia and divided into three sections each. The sections were randomized to SLB, HSB, or control (C, no biopsy) groups. Tissue samples were excised after placement of a suture loop formed by a 4S Roeder knot and oversewn with a Cushing pattern using bar...
McCarty CA, Thomason JJ, Gordon K, Burkhart T, Bignell W.We wished to add to the existing baseline data on impact loading of the distal limb as a precursor to assessing the potential role of impact in injury and joint disease. Objective: To examine the effect of 3 hoof-strike conditions (toe first, flat and heel first) and 2 specimen masses (with and without a ballast of ∼2% body mass) on impact deceleration and vibration frequencies and energies at the hoof, first phalanx and third metacarpal. Methods: Biomechanical experiments in cadaver material. Methods: Eight cadaver limbs were subjected to randomised, repeated controlled trials, in which the...
Pressanto MC, Pascoletti G, Perkins JD, Zanetti EM, Beccati F, Santalucia V, Pepe M.To validate the use of a polyblend tape suture in equine laryngoplasty (PL). Methods: Experimental study. Methods: Thirty-two cadaveric larynges. Methods: Each larynx was randomly assigned to 1 of 4 groups: PL with polyblend tape suture (TigerTape), without (TT) or with a cannula (TTC) in the muscular process of the arytenoid cartilage, and PL with polyester suture (Ethibond), without (EB) or with a cannula (EBC). Construct stiffness, total migration, creep, and drift values were measured after 3000 cycles. The specimens were then loaded to failure to assess their residual properties: load a...
Hart KA, Sherlock CE, Davern AJ, Lewis TH, Robertson TP.N-butylscopolammonium bromide (NBB) is an anticholinergic agent used to treat spasmodic colic in horses. Intestinal smooth muscle spasm also occurs in horses with intraluminal intestinal obstructions, such as ileal impactions. The antispasmodic effects of NBB may be useful in managing ileal impactions, but the effects of NBB on equine ileal smooth muscle are unknown. Objective: To investigate the effects of NBB on spontaneous and induced contraction of the equine ileum in an ex vivo model. Methods: Ex vivo biomechanical study assessing contractile properties in isolate equine ileal smooth musc...
Rossi TM, Smith SA, McMichael MA, Wilkins PA.To evaluate the degree of activation of the contact pathway in citrated equine whole blood over holding times ≤ 30 minutes and assess effects of contact activation on recalcification-initiated thromboelastometry. Methods: 11 healthy adult mixed-breed horses. Methods: Blood was collected by atraumatic jugular venipuncture into prewarmed evacuated siliconized glass tubes containing citrate anticoagulant and held at 37°C for ≤ 30 minutes. Thromboelastometry was performed with an in vitro viscoelasticity (thromboelastometry) monitoring system. Factor XII and factor XI procoagulant activities ...
Canola PA, Cardenas JJ, Sá GC, de Paula VB.To evaluate the feasibility of performing needle arthroscopy of the scapulohumeral joint and bicipital bursa in standing horses by using the thoracic limbs of euthanized horses. To that purpose, this experimental study was designed. Ten thoracic limbs, five left and five right from euthanized horses were retained in an upright position to simulate a standing horse. The craniolateral and lateral scapulohumeral arthroscopic portals were used to access the articular structures. A third (caudal) portal was also identified and described. The degree of difficulty in accessing the articular space and...
Giusto G, Gandini M.In equine abdominal surgery, resection and anastomosis of strangulated intestine is a commonly performed procedure. To date, ligatures, vessel sealing devices and the ligate-divide stapler have been described for this use in horses. The objective of this study was to compare the application of haemostatic clips and ligatures to occlude equine mesenteric vessels. Portions of jejunum with ten associated mesenteric vessels were collected from 12 horses at a local abattoir and divided into two groups. Portions of intestine were divided into two sections comprising five vessels each and assigned to...
Lynch NP, Jones SA, Bazley-White LG, Wilson ZF, Raffetto J, Pfau T, Cheetham J, Perkins JD.To identify the degree of left arytenoid cartilage (LAC) abduction that allows laryngeal airflow similar to that in galloping horses, assess 2-D and 3-D biomechanical effects of prosthetic laryngoplasty on LAC movement and airflow, and determine the influence of suture position through the muscular process of the arytenoid cartilage (MPA) on these variables. Methods: 7 equine cadaver larynges. Methods: With the right arytenoid cartilage maximally abducted and inspiratory airflow simulated by vacuum, laryngeal airflow and translaryngeal pressure and impedance were measured at 12 incremental LAC...
Unterköfler MS, McGorum BC, Milne EM, Licka TF.In horses a number of small intestinal diseases is potentially life threatening. Among them are Equine Grass Sickness (EGS), which is characterised by enteric neurodegeneration of unknown aetiology, as well as reperfusion injury of ischaemic intestine (I/R), and post-operative ileus (POI), common after colic surgery. The perfusion of isolated organs is successfully used to minimize animal testing for the study of pathophysiology in other scenarios. However, extracorporeal perfusion of equine ileum sourced from horses slaughtered for meat production has not yet been described. Therefore the pre...
Boss CK, Gibson DJ, Schultz G, Whitley RD, Hernandez JA, Abbott JR, Plummer CE.To investigate the therapeutic effects of topical equine amniotic membrane (eAM) suspension following corneal wounding in a controlled experimental setting. Methods: Equine amniotic membrane was collected, gamma irradiated, homogenized for topical suspension preparation, and cryopreserved. Corneoscleral rims harvested from fresh rabbit globes were wounded via keratectomy and were maintained in an air-liquid interface ex vivo corneal culture model. Treatment groups included topical gamma irradiated eAM suspension (n = 20) and a control group (n = 20). Re-epithelialization of the wound was a...
Himebaugh NE, Robertson JB, Weninger K, Gilger BC, Ekesten B, Oh A.The aim of this study was to assess the transmission of the ultraviolet (UV) radiation (200-400 nm) through intact enucleated globes of different species (dogs, cats, pigs, rabbits, horses, and humans) using spectrophotometry. Globes of cats (n = 6), dogs (n = 18), pigs (n = 10), rabbits (n = 6), horses (n = 10), and humans (n = 4) were analyzed. A 5-10 mm circular area of sclera and choroid from the posterior aspect of the globe was removed under a surgical microscope, leaving the retina intact in all species except the horse. Glass coverslips were added in horses and rabbits du...
Verwilghen D, Ponthier J, Van Galen G, Salciccia A, Sandersen C, Serteyn D, Grulke S.Radial extracorporeal shockwave therapy (ESWT) is widely used in equine practice for the treatment of orthopedic problems. However, its original use as a lithotripsy device in human and canine urology led us to postulate that it could be used as an alternative to the surgical treatment of urethral calculi in horses. Objective: Radial ESWT can easily and safely fragment calculi in the distal urethra of the horse. Methods: Two postmortem cases and 1 live case of obstructive urinary disease admitted at the Veterinary Teaching Hospital of Liege. Methods: A radial shockwave device was directly appl...
Pollaris E, Broeckx BJG, Rajasekharan S, Cauwels R, Vlaminck L. fracture models are frequently used in human dentistry to provide insights in the fracture mechanisms of teeth. Equine cheek teeth fractures are an important dental pathology, but there has been no research performed to examine the fracture resistance . To evaluate the fracture resistance of equine cheek teeth and identify anatomical predictors that might influence fracture resistance in healthy teeth. It was further evaluated if the presence of a fissure caused a decrease in fracture resistance. experimental design. Individual cheek teeth were subjected to a compression load in a univer...
