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.
Seeto WJ, Tian Y, Winter RL, Caldwell FJ, Wooldridge AA, Lipke EA.A common challenge in cell therapy is the inability to routinely maintain survival and localization of injected therapeutic cells. Delivering cells by direct injection increases the flexibility of clinical applications, but may cause low cell viability and retention rates due to the high shear forces in the needle and mechanical wash out. In this study, we encapsulated endothelial colony forming cells (ECFCs) in poly(ethylene glycol)-fibrinogen (PF) hydrogel microspheres using a custom-built microfluidic device; this system supports rapid encapsulation of high cell concentrations (10 million c...
Major DS, Duff AH, Cohen ND, Hardy J.To compare laparoscopic single-layer versus double-layer closure of experimental, full-thickness incisions in adult equine urinary bladders using unidirectional and bidirectional barbed suture. Methods: Experimental, ex vivo, surgical study. Methods: Thirty adult equine cadaver urinary bladders. Methods: Bladders were randomly divided into 5 groups (n = 6): intact controls, bladders sutured with unidirectional or bidirectional barbed suture in a single-layer closure, and bladders sutured with unidirectional or bidirectional barbed suture in a double-layer closure. A 5-cm apical incision wa...
Mouser VHM, Dautzenberg NMM, Levato R, van Rijen MHP, Dhert WJA, Malda J, Gawlitta D.The implantation of chondrocyte-laden hydrogels is a promising cartilage repair strategy. Chondrocytes can be spatially positioned in hydrogels and thus in defects, while current clinical cell therapies introduce chondrocytes in the defect depth. The main aim of this study was to evaluate the effect of spatial chondrocyte distribution on the reparative process. To reduce animal experiments, an ex vivo osteochondral plug model was used and evaluated. The role of the delivered and endogenous cells in the repair process was investigated. Full thickness cartilage defects were created in equine ost...
Geiger SM, Reich E, Böttcher P, Grund S, Hagen J.Biplane high-speed fluoroscopy is a new method for gait analysis of the equine distal extremity. This is the first study validating the noninvasive tracking possibilities (Autoscoping and Scientific Rotoscoping) taking equine anatomy into account. Objective: To determine the resolution with which Autoscoping and Scientific Rotoscoping depict motion of the equine phalanges in comparison to the invasive gold standard marker-based registration. Methods: Comparative ex vivo study. Methods: In 5 distal extremities of slaughtered ponies, 3 or 4 tantalum beads with 1 mm diameter were implanted in e...
Dubuc J, Girard C, Richard H, De Lasalle J, Laverty S.There is limited information available concerning normal equine meniscal morphology, its degeneration and role in osteoarthritis (OA). Objective: To characterise normal equine meniscal morphology and lesions and to explore the relationship between equine meniscal degeneration and femorotibial OA. Methods: Ex vivo cadaveric study. Methods: Menisci were harvested from 7 normal joints (n = 14 menisci) and 15 joints with OA (n = 30 menisci). A macroscopic femorotibial OA score (cartilage degeneration and osteophytosis) was employed to measure disease severity in each compartment. The femoral and t...
Comino F, Giusto G, Caramello V, Gandini M.The Serra and Reimer emasculators are frequently used in equine orchiectomy. They differ in jaw profile and the mechanism by which they achieve haemostasis. Objective: To investigate whether the haemostatic capacities of the Reimer and Serra emasculators in open and closed castration differ, to compare the haemostatic capacities of each emasculator in both open and closed castration, and to assess whether the tensile strength of the parietal tunic in closed castration differs according to whether a Reimer or Serra emasculator is used. Methods: Ex vivo randomised study. Methods: Eighty equine c...
Sprick M, Fürst A, Baschnagel F, Michel S, Piskoty G, Hartnack S, Jackson MA.To evaluate the damage inflicted by an unshod hoof and by the various horseshoe materials (steel, aluminium and polyurethane) on the long bones of horses after a simulated kick. Methods: Sixty-four equine radii and tibiae were evaluated using a drop impact test setup. An impactor with a steel, aluminium, polyurethane, or hoof horn head was dropped onto prepared bones. An impactor velocity of 8 m/s was initially used with all four materials and then testing was repeated with a velocity of 12 m/s with the polyurethane and hoof horn heads. The impact process was analysed using a high-speed camera...
Siemieniuch MJ, Gajos K, Kozdrowski R, Nowak M.Even if mares continue to breed up to an advanced age, in aging mares reproductive failure is quite common. Subclinical endometritis, which occurs more often in aging mares than in younger counterparts, may cause prolongation or shortening of the inter-estrus period or the corpus luteum lifespan. We hypothesized that during subclinical endometritis the secretion of selected arachidonic acid metabolites may differ in aging mares compared to younger females. To verify this thesis, ex vivo organ cultures of endometrium were established with subsequent measurements of concentrations of prostaglan...
Calzetta L, Rogliani P, Mattei M, Alfonsi P, Cito G, Pistocchini E, Cazzola M, Matera MG.Equine airways represent a suitable ex vivo model to study the functional impact of pharmacological treatments on human chronic obstructive pulmonary disorders, such as asthma and chronic obstructive pulmonary disease (COPD). We aimed to characterize the pharmacological interaction between the long-acting muscarinic antagonist (LAMA) tiotropium and the long-acting β-agonist (LABA) olodaterol in equine airways. The effect of tiotropium and olodaterol, administered alone and in combination at the ratio of concentrations reproducing ex vivo the concentration-ratio delivered by the currently avai...
Parra N, Jaume M, Boscán K, Hernández A, Mijares A, González M, Alvarado Y, Restrepo J.Trypanosoma equiperdum is the causative agent of dourine, a venereal disease in horses and donkeys. This parasite has a widely distribution, is found in Africa, Asia, Southern and Eastern Europe, Russia, Mexico and Venezuela. The T. equiperdum is morphologically indistinguishable to other Trypanozoon species, however differs from other mammalian trypanosomes due to the fact that it is primarily a tissue parasite, generating cutaneous plaques, swelling of genitalia and neurological signs. The aim of this study was to evaluate the trypanocidal effectiveness of a set of derivatives of thiosemicar...
Brandenberger O, Rossignol F, Perkins JD, Lechartier A, Mespoulhès-Rivière C, Vitte A, Rossignol A, Ducharme N, Boening KJ.To determine the biomechanical properties of 5 suture constructs in the equine cricoid under cyclic loading and load to failure testing. Methods: Ex vivo study. Methods: Seventy-five equine cadaver larynges. Methods: Each larynx was implanted with 1 of 5 cricoid-suture constructs. The standard laryngoplasty, where a suture is passed once through the cricoid, including its caudal edge, was used in 2 constructs: 1 with 5 USP Ethibond (ES) and 1 with 2 mm Fibertape (FS). In the third construct, the 2 mm Fibertape was passed twice through the cricoid including its caudal edge (Double Loop-DL). Con...
Ahern BJ, Van Eps AW, Boston RC, Franklin SH.To determine the degree and ease of arytenoid abduction achieved with abaxial placement of a FASTak II suture anchor compared to 2 suture patterns with different directions of insertion-caudomedial to craniolateral and medial to lateral. Methods: Ex vivo experimental. Methods: Cadaveric larynges from 10 Standardbred racehorses. Methods: Each larynx was sequentially instrumented with all 3 arytenoid suture attachment in random order: (1) abaxial placement of a FASTak II suture, (2) caudomedial to craniolateral suture, and (3) medial to lateral suture placement. Each construct was abducted at 5N...
Tidd N, Michelsen J, Hilbert B, Quinn JC.Gene-directed tissue repair offers the clinician, human or veterinary, the chance to enhance cartilage regeneration and repair at a molecular level. Non-viral plasmid vectors have key biosafety advantages over viral vector systems for regenerative therapies due to their episomal integration however, conventional non-viral vectors can suffer from low transfection efficiency. Our objective was to identify and validate in vitro a novel non-viral gene expression vector that could be utilized for ex vivo and in vivo delivery to stromal-derived mesenchymal stem cells (MSCs). Minicircle plasmid DNA v...
Harlow BE, Lawrence LM, Harris PA, Aiken GE, Flythe MD.Cereal grains are often included in equine diets. When starch intake exceeds foregut digestion starch will reach the hindgut, impacting microbial ecology. Probiotics (e.g., lactobacilli) are reported to mitigate GI dysbioses in other species. This study was conducted to determine the effect of exogenous lactobacilli on pH and the growth of amylolytic and lactate-utilizing bacteria. Feces were collected from 3 mature geldings fed grass hay with access to pasture. Fecal microbes were harvested by differential centrifugation, washed, and re-suspended in anaerobic media containing ground corn, whe...
Aldrich ED, Earnest J, Moorman VJ.To compare a 2-layer closure with suture line reversal for a pelvic flexure enterotomy to 1-layer and traditional 2-layer hand sewn closures. Methods: Ex vivo, simple randomized study. Methods: Large colon segments from adult horses (n = 18). Methods: Pelvic flexures were harvested from 18 horses and randomly assigned to 1 of 3 closure techniques (n = 6 per technique). A 10-cm enterotomy was made in each pelvic flexure and closed with the assigned technique. Closure time, luminal diameter via contrast radiographs, and bursting pressure were recorded for each specimen and compared betwe...
Sarin JK, Brommer H, Argüelles D, Puhakka PH, Inkinen SI, Afara IO, Saarakkala S, Töyräs J.We investigate the potential of a prototype multimodality arthroscope, combining ultrasound, optical coherence tomography (OCT) and arthroscopic indentation device, for assessing cartilage lesions, and compare the reliability of this approach with conventional arthroscopic scoring ex vivo. Areas of interest (AIs, N = 43) were selected from equine fetlock joints (N = 5). Blind-coded AIs were independently scored by two equine surgeons employing International Cartilage Repair Society (ICRS) scoring system via conventional arthroscope and multimodality arthroscope, in which high-frequency ul...
Hernandez D, Yeo WM, Brooks MB, Ness SL, Divers TJ, Stokol T.OBJECTIVE To evaluate the effects of treatment of horses with standard platelet inhibitors on ex vivo inhibition of platelet activation by equine herpesvirus type I (EHV-I). ANIMALS II healthy adult horses. PROCEDURES In a double-blinded, placebo-controlled crossover study, horses were treated orally for 5 days with theophylline (5 mg/kg, q 12 h), pentoxifylline (10 mg/kg, q 12 h), clopidogrel bisulfate (4 mg/kg, q 24 h), acetylsalicylic acid (20 mg/kg, q 24 h), or placebo. Horses received all treatments, each separated by a 3-week washout period. Platelet-rich plasma was prepared from citrate...
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...
Anderson SL, Bracamonte JL, Hendrick S, Carmalt JL, Wilson DG.To compare bursting strength and failure mode between ventral median (VM) and right ventral paramedian (RVP) celiotomies closed with 1 section of USP 7 braided polydioxanone (7PD). Methods: Ex vivo experimental. Methods: Equine cadavers (n = 12). Methods: A 25 cm VM or RVP (positioned 5 cm lateral to the linea alba) celiotomy was created in fresh equine cadavers. A 200 L polyurethane bladder was inserted into the abdomen. Celiotomies were closed in a simple continuous pattern with 1 section of 7PD. The bladder was inflated with compressed air until construct failure. Horse signalment, body wei...
Wood AD, Sinovich M, Prutton JSW, Parker RA.To evaluate the accuracy of ultrasonographic guidance for injection near the ventral rami of the cervical spinal nerves (VRCSN). Methods: Ex vivo study. Methods: Ten cadavers (n = 40 injections). Methods: Left and right VRCSN at C4/5 and C5/6 were infiltrated at the intervertebral foramen (IVF) under ultrasonographic guidance. A vertically orientated 3.5-MHz curvilinear probe was used to identify the craniocaudal midpoint of the articular process joint (APJ). The probe was moved ventrally until the IVF was identified. An 18-gauge 15-cm-long spinal needle was aimed immediately below the ventral...
Depuydt E, Chiers K, Van Hecke L, Saunders J, Martens A, Pille F, Spaas JH.Injuries to equine tendons and ligaments are career-compromising, causing reduced performance and premature retirement. Promising treatment alternatives have been investigated in the field of mesenchymal stem cells (MSCs). In this study, the tissue adherence and protein expression of tenogenic primed mesenchymal stem cells (tpMSCs) after administration to ex vivo tendon and ligament explants is investigated. First, collagen type I (COL I) and smooth muscle actin (SMA) expression was assessed in cytospins prepared from native MSCs and tpMSCs. Second, equine superficial digital flexor tendon and...
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...
Rosser JM, Brounts S, Livesey M, Wiedmeyer K.Our objective was to compare thoracoabdominal (TA Premium™ 90) stapled enterotomy closure to traditional hand-sewn closure, using time to perform the technique, luminal diameter, and bursting pressure in ex-vivo specimens. The pelvic flexures of 13 client-owned horses were harvested. Each pelvic flexure had 1 enterotomy performed; 6 were closed via staples, 7 closures were hand-sewn. Luminal diameter at the enterotomy site was assessed via contrast radiography performed pre-and post-enterotomy. Bursting pressure of the closure was assessed by continuous manometry during rapid infusion. Time ...
Barton MH, Ferguson D, Davis PJ, Moore JN.Pentoxifylline (7.5 mg/kg) was bolused intravenously to eight healthy horses and was immediately followed by infusion (1.5 mg/kg/h) for 3 h. Clinical parameters were recorded and blood samples were collected for 24 h. Plasma was separated and concentrations of pentoxifylline, its reduced metabolite I, and 6-keto-prostaglandin F1 alpha were determined. Heparinized whole blood was also incubated ex vivo with 1 ng Escherichi coli endotoxin/mL blood for 6 h before determination of plasma tumour necrosis factor activity. The peak plasma concentrations of pentoxifylline and metabolite I occurred at ...
Fuerst AE, Oswald S, Jäggin S, Piskoty G, Michel S, Auer JA.The objective of this postmortem study was to determine the fracture configurations of the equine radius and tibia after a simulated kick. Fracture configurations of 35 radii and 36 tibiae from 19 adult horses were evaluated after a simulated kick in an experimental ex-vivo study. The bones were dissected, the proximal and distal ends were embedded in resin, fixed horizontally and preloaded in compression, and a steel impactor, designed to simulate a shod equine hoof, was dropped from a height of three to six metres onto the diaphysis. The experiments were filmed with a high-speed camera (30,0...
Jenson PW, Lillich JD, Roush JK, Gaughan EM.To test the failure strength and energy of 2 bioabsorbable implants applied to transected deep digital flexor tendons (DDFT) from adult horses. Methods: Ex vivo biomechanical experiment. Methods: Twelve pairs of deep digital flexor tendons harvested from the forelimbs of fresh equine cadavers. Methods: Poly-L-lactic acid tendon plates were custom manufactured for application to the cylindrical surface of an adult equine deep digital flexor tendon. Twelve pairs of DDFTs were transected 2 cm distal to the insertion of the distal check ligament of the deep digital flexor tendon. One tendon of eac...
Aparicio IM, Rojo-Domínguez P, Castillejo-Rufo A, Peña FJ, Tapia JA.Despite its importance in somatic cells and during spermatogenesis, little is known about the role that autophagy may play in ejaculated spermatozoa. Our aim was to investigate whether the molecular components of autophagy, such as microtubule-associated protein 1 light chain 3 (LC3), are activated in stallion spermatozoa during the capacitation and acrosome reaction and if this activation could modulate these biological processes. To analyze the autophagy turnover, LC3I and LC3II proteins were assessed by western blotting, and the ratio between both proteins (LC3II/LC3I) was calculated. In so...
Giusto G, Caramello V, Comino F, Gandini M.In this study the caecum and large colon were harvested from 24 slaughtered horses. On each sample, an 8‑cm long enterotomy was performed. Enterotomies were closed using either barbed or unbarbed glycomer‑631. We compared the time to close, appearance, length of suture material, bursting pressure, and costs associated with each type of material. Our findings demonstrated that time to close was significantly shorter (caecum, P = 0.034; pelvic flexure, P = 0.039) using barbed sutures (caecum 610.4 seconds; pelvic flexure 699.3 seconds) than unbarbed sutures (caecum 661.0 seconds, pelvic flex...
Anderson SL, Bracamonte JL, Hendrick S.The objective of this study was to compare the bursting strength (BS) and mode of failure (MF) of ventral midline (VM) celiotomies closed with USP 7 polydioxanone (7PD) in 1 or 2 simple continuous sections. A bursting strength model, consisting of inserting and inflating a 200-L polyurethane bladder through a 25-cm VM celiotomy, was used on 15 fresh equine cadavers. Celiotomies were closed using 7PD in 2 separate sections (4 knots), 2 continuous sections (3 knots), or a single section (2 knots) using a simple continuous pattern. The horses' signalment, body weight, number of total knots, MF, a...
Hoffmann SL, Seminoff K, McKemie DS, Kass PH, Knych HK.Grapiprant is a prostaglandin E2 receptor antagonist that has been found to be an effective anti-inflammatory in dogs and that is devoid of some of the adverse effects associated with traditional NSAIDs that elicit their effects through inhibition of PGE2 production. Previously published reports have described the pharmacokinetics of this drug in horses when administered at 2 mg/kg; however, pharmacodynamic effects in this species have yet to be described. The objective of the current study was to describe the pharmacokinetics and pharmacodynamics of grapiprant at a higher dose. Eight horses...
Viljanto M, Kaabia Z, Taylor P, Muir T, Habershon-Butcher J, Bailly-Chouriberry L, Scarth J.Boldenone is an anabolic-androgenic steroid that is prohibited in equine sports. However, in certain situations, it is endogenous or is believed to be formed by microbes in urine, and therefore, an approach for the differentiation is required. Following the identification of Δ1-progesterone and 20(S)-hydroxy-Δ1-progesterone as potential biomarkers of microbial activity, the presence of six steroids was investigated in the postrace urine of castrated male horses (geldings, n = 158). In line with endogenous findings from several other species when ultrasensitive methods are employed, bolde...
Monteiro de Barros MR, Davies-Morel MCG, Mur LAJ, Creevey CJ, Alison RH, Nash DM.Persistent mating-induced endometritis is a major cause of poor fertility rates in the mare. Endometritis can be investigated using an ex vivo equine endometrial explant system which measures uterine inflammation using prostaglandin F2α as a biomarker. However, this model has yet to undergo a wide-ranging assessment through transcriptomics. In this study, we assessed the transcriptomes of cultured endometrial explants and the optimal temporal window for their use. Endometrium harvested immediately post-mortem from native pony mares (n = 8) were sampled (0 h) and tissue explants were cultured ...
Wehrman RF, Genschel U, Charli A, Kanthasamy AG, Allbaugh RA, Ben-Shlomo G.To establish a physiologically relevant ex vivo model of equine corneal epithelial wound healing. Methods: Fourteen equine corneas were randomly assigned to one of two groups: wounded (n = 8) or unwounded (n = 6) controls. In the wounded group, the axial corneal epithelium was removed by applying a 6 mm filter paper disk soaked in 1N-NaOH for 60 s. Corneas were subsequently cultured using an air-liquid interface model. Evaluation of corneal healing was performed daily, and culture medium was collected. Corneas were randomly assigned to undergo processing via histopathology and RNAscope i...
Nagy A, Bodò G, Dyson SJ, Compostella F, Barr AR.Evidence-based information is limited on distribution of local anaesthetic solution following perineural analgesia of the palmar (Pa) and palmar metacarpal (PaM) nerves in the distal aspect of the metacarpal (Mc) region ('low 4-point nerve block'). Objective: To demonstrate the potential distribution of local anaesthetic solution after a low 4-point nerve block using a radiographic contrast model. Methods: A radiodense contrast medium was injected subcutaneously over the medial or the lateral Pa nerve at the junction of the proximal three-quarters and distal quarter of the Mc region (Pa inject...
Guan F, Fay S, Li X, You Y, Robinson MA.Bioactive peptides pose a great threat to sports integrity. The detection of these peptides is essential for enforcing their prohibition in sports. Identifying the catabolites of these peptides that are formed ex vivo in plasma may improve their detection. In the present study, the stability of 27 bioactive peptides with protection at both termini in equine plasma was examined under different incubation conditions, using HILIC coupled to HRMS. Of the 27 peptides, 13 were stable after incubation at 37°C for 72 hr, but the remaining 14 were less stable. Ex vivo catabolites of these 14 peptides ...
Muñoz JA, Stephen J, Baptiste KE, Lepage OM.The objective of this study was to evaluate the feasibility, efficacy and complications following lavage and drainage of the lateral compartment (LC) of the equine guttural pouch (GP) using a modified Garm's technique (MGT). In an ex vivo study (study 1), six cadaver heads were examined to assess the anatomical limits of the surgical approach and whether vital structures might be damaged. This was followed by an in vivo study (study 2) in which a lavage/drainage tube was placed for 3 days into each LC of four standing horses using the MGT. In both studies, the procedure offered direct access i...
Pascoletti G, Pressanto MC, Putame G, Terzini M, Audenino AL, Zanetti EM.A number of surgical practices are aimed to compensate for tissue relaxation or weakened/atrophied muscles by means of suture prostheses/thread lifts. The success rate of these procedures is often very good in the short term, while it is quite variable among subjects and techniques in the middle-long term. Middle-long term failures are mostly related to suture distraction, loosening or wear, coming from repeated loading cycles. In this work, an experimental device to perform ex vivo tests on prosthetic sutures has been set up. An equine laryngoplasty has been used as a benchmark, being represe...
Brütsch DR, Hunziker P, Pot S, Tappeiner C, Voelter K.Intraocular fibrin clots caused by severe uveitis can be a sight-threatening condition that needs to be resolved quickly and reliably. Intracameral injection of tissue-plasminogen activator (tPA) is commonly used to resolve intraocular fibrin. However, the drug does not reach fibrinolytic concentrations after topical application. Desmoteplase (DSPA) is a structurally similar but smaller fibrinolytic agent with a higher fibrin selectivity, a longer half-life, and better biocompatibility compared with tPA. This study was designed to evaluate the corneal and scleral permeability of DSPA in rabbit...
Peek SF, Borah S, Semrad S, McGuirk S, Slack JA, Patton E, Coombs D, Lien L, Darien BJ.Accurate determination of plasma endotoxin concentration is critical for ex vivo and in vitro cellular and molecular studies of endotoxemia in horses. However, reports are conflicting with respect to anticoagulant, handling, and sample preparation. Objective: The purpose of this study was to determine the effect of blood sample fraction and handling time on measurement of endotoxin concentration in horses. Methods: Whole blood, anticoagulated with 3.8% (0.12 M) sodium citrate (9:1), was collected from 5 healthy horses. Whole blood (WB), platelet-rich plasma (PRP), and platelet-poor plasma (PPP...
Baudisch N, Singer E, Jensen KC, Eichler F, Meyer HJ, Lischer C, Ehrle A.Surgical treatment options for horses with overriding dorsal spinous processes include interspinous ligament desmotomy and partial spinous process ostectomy. The impact of spinal surgery on the three-dimensional biomechanics of the equine thoracolumbar spine and the epaxial musculature is unclear. Objective: To investigate the influence of interspinous ligament desmotomy and cranial wedge ostectomy on the biomechanics of the equine thoracolumbar spine and the paraspinal Musculi multifidi. Methods: Ex-vivo experiments. Methods: Twelve equine thoracolumbar spine specimens were mounted in a custo...
Irandoust S, O'Neil LM, Stevenson CM, Franseen FM, Ramzan PHL, Powell SE, Brounts SH, Loeber SJ, Ergun DL, Whitton RC, Henak CR, Muir P.Catastrophic injury has a low incidence but leads to the death of many Thoroughbred racehorses. Objective: To determine sensitivity, specificity, and reliability for third metacarpal condylar stress fracture risk assessment from digital radiographs (DR) and standing computed tomography (sCT). Methods: Controlled ex vivo experiment. Methods: A blinded set of metacarpophalangeal joint DR and sCT images were prepared from 31 Thoroughbreds. Four observers evaluated the condyles and parasagittal grooves (PSG) of the third metacarpal bone for the extent of dense bone and lucency/fissure and assigned...
Sheahan BJ, Schubert AG, Schubert W, Sheats MK, Schnabel LV, Gilbertie JM.Neutrophil extracellular traps (NETs) play a significant role in response to a variety of infectious and inflammatory stimuli in human and veterinary medicine. Although entrapment of bacteria can be an important function of NETs, the exuberant release of DNA and other intracellular molecules has also been negatively implicated in the pathogenesis of different diseases. Thus, NET formation must be tightly controlled and represents an opportunity for therapeutic interventions. Horses are particularly sensitive to bacterial stimuli that have previously been shown to cause NETs in other species, b...
Les CM, Stover SM, Taylor KT, Keyak JH, Willits NH.The objective of this study was to examine several simple ex vivo loading conditions for the equine metacarpus, and to evaluate their ability to reproduce the mid-diaphyseal bone surface strain distributions previously reported in vivo at the walk and trot. Distributed axial compressive loads, and 9 different axial compressive point loads at -7.5 kN and -15 kN were applied to metacarpal-distal carpal bone preparations from 6 Thoroughbred horses, aged 1-5 years. The resulting dorsal, medial, palmar, and lateral mid-diaphyseal bone surface axial and shear strains were compared with previously re...
Finco DR, Groves C.Free-flow and stop-flow procedures conducted on 2 female and 2 testosterone-treated castrated male ponies indicated that [14C]inulin and exogenous creatinine clearance values were the same. These results indicated that creatinine was neither reabsorbed nor secreted by the renal tubules and that exogenous creatinine clearance was an accurate method for determining glomerular filtration rate. As in other species which have been studied, endogenous creatinine clearance probably underestimated glomerular filtration rate because of the presence of noncreatinine chromogens in plasma.
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...
