In vivo studies involving horses refer to research conducted within living organisms to understand various biological processes, disease mechanisms, and therapeutic interventions in equine species. These studies provide insights into the physiological and pathological responses of horses under natural conditions. In vivo research encompasses a range of investigations, including pharmacokinetics, disease modeling, and the evaluation of treatment efficacy. It often involves the use of controlled environments to simulate real-life scenarios while observing the effects of specific variables on equine health. This page gathers peer-reviewed research articles and scholarly studies that explore the methodologies, findings, and implications of in vivo research in horses, contributing to the advancement of equine science and veterinary medicine.
Tofflemire K, Whitley EM, Allbaugh R, Ben-Shlomo G, Griggs A, Strong T, Whitley RD.To evaluate the effect of topical ophthalmic 0.005% latanoprost alone and in combination with 0.1% diclofenac on healthy horses. Methods: Twelve healthy adult horses. Methods: A randomized, masked crossover design was used with horses divided into three groups for once daily treatment in one randomly selected eye. For arm 1 of the study, Group D (n = 3) received 0.1% diclofenac, Group L (n = 3) received 0.005% latanoprost, and Group DL (n = 6) received 0.005% latanoprost and 0.2 ml of 0.1% diclofenac. For arm 2 of the study, horses from Group D and L were placed into Group DL and horses from G...
Te Moller NCR, Pitkänen M, Sarin JK, Väänänen S, Liukkonen J, Afara IO, Puhakka PH, Brommer H, Niemelä T, Tulamo RM, Argüelles Capilla D....Arthroscopic optical coherence tomography (OCT) is a promising tool for the detailed evaluation of articular cartilage injuries. However, OCT-based articular cartilage scoring still relies on the operator's visual estimation. Objective: To test the hypothesis that semi-automated International Cartilage Repair Society (ICRS) scoring of chondral lesions seen in OCT images could enhance intra- and interobserver agreement of scoring and its accuracy. Methods: Validation study using equine cadaver tissue. Methods: Osteochondral samples (n = 99) were prepared from 18 equine metacarpophalangeal joint...
Partlow JL, Lustgarten M, Redding WR.To the authors' knowledge, the ultrasonographic appearance of hair shafts within a synovial structure of the horse has not been described previously. The purpose of this descriptive study was to illustrate the clinical, ultrasonographic, and arthroscopic characteristics of confirmed hair shafts within synovial structures of seven horses. A review of medical records of the Farm and Equine Veterinary Medical Center at North Carolina State University College of Veterinary Medicine identified seven horses with clinical signs suspicious for inflammatory or septic synovitis/tenosynovitis that had ha...
Brosnahan MM, Silvela EJ, Crumb J, Miller DC, Erb HN, Antczak DF.Invasive trophoblast from Day 34 horse conceptuses survives in extrauterine sites in allogeneic recipients that are immunologically naive to donor major histocompatibility complex class I antigens. The ectopic trophoblast retains its in utero characteristics, including similar lifespan, physiologic effect of its secreted product (equine chorionic gonadotropin) upon the recipient's ovaries, and induction of host immune responses. Immunologic memory has not been considered previously in this experimental system. We hypothesized that primary exposure to ectopic trophoblast would affect the recipi...
Arbabi V, Pouran B, Weinans H, Zadpoor AA.Investigation of the solute transfer across articular cartilage and subchondral bone plate could nurture the understanding of the mechanisms of osteoarthritis (OA) progression. In the current study, we approached the transport of neutral solutes in human (slight OA) and equine (healthy) samples using both computed tomography and biphasic-solute finite element modeling. We developed a multi-zone biphasic-solute finite element model (FEM) accounting for the inhomogeneity of articular cartilage (superficial, middle and deep zones) and subchondral bone plate. Fitting the FEM model to the concentra...
Fotschki J, Szyc AM, Laparra JM, Markiewicz LH, Wróblewska B.The aim of this study was to examine immune adaptive changes, the expression of innate biomarkers and variations in intestinal microbiota composition after horse-milk administration in BALB/c mice, which were sensitized intraperitoneally using cow β-lactoglobulin and α-casein with aluminum adjuvant. We measured serum antibody IgE levels and the expression of MCP-1, IL-4, and TNF-α in duodenal samples. Changes in immune cell populations in peripheral blood were quantified using flow cytometry, and intestinal microbiota composition was assessed using real-time PCR. We found that horse-milk ad...
Gottschalk M, Sieme H, Martinsson G, Distl O.A high quality of stallion semen is of particular importance for maximum reproductive efficiency. In the present study, we estimated the relationships among estimated breeding values (EBVs) of semen traits and EBVs for the paternal component of the pregnancy rate per estrus cycle (EBV-PAT) for 100 German Warmblood stallions using correlation and general linear model analyses. The most highly correlated sperm quality trait was total number of progressively motile sperm (r = 0.36). EBV-PAT was considered in three classes with stallions 1 SD below (<80), around (80-120), and above (>120) the popu...
Bodaan CJ, Wise LM, Wakelin KA, Stuart GS, Real NC, Mercer AA, Riley CB, Theoret C.Healing is delayed in limb wounds relative to body wounds of horses, partly because of sustained inflammation and inefficient angiogenesis. In laboratory animals, proteins derived from orf virus modulate these processes and enhance healing. We aimed to compare immune cell trafficking and the inflammatory, vascular, and epidermal responses in body and limb wounds of horses and then to investigate the impact of orf virus interleukin-10 and vascular endothelial growth factor-E on these processes. Standardized excisional wounds were created on the body and forelimb of horses and their progression ...
Barrachina L, Remacha AR, Soler L, García N, Romero A, Vázquez FJ, Vitoria A, Álava MÁ, Lamprave F, Rodellar C.Acute phase proteins are useful inflammatory markers in horses. Haptoglobin (Hp) serum level is increased in horses undergoing different inflammatory processes, including arthritis. However, Hp concentration has not been assessed in inflammatory synovial fluid (SF). The aim of the present study was to investigate the Hp response in serum and SF in horses undergoing experimentally induced arthritis. For this purpose, serum and SF samples were collected from 12 animals before amphotericin B-induced arthritis was created (T0, healthy) and 15days after the lesion induction (T1, joint inflammation)...
Equine sarcoids develop upon bovine papillomavirus type 1 or 2 (BPV1, BPV2) infection in conjunction with trauma and represent the most common tumour disease in horses and other equids, including donkeys. In face of a sarcoid outbreak involving 12 of 111 donkeys and mules at the 'Rifugio degli Asinelli', a subsidiary charity organization of The Donkey Sanctuary, non-invasively collected sample material including crusts, dandruff, swabs and hair roots was collected from sarcoid-affected and 26 healthy donkeys, as well as dandruff from a grooming kit and tabanids caught from or in the vicinity o...
Metcalf GL, McClure SR, Hostetter JM, Martinez RF, Wang C.Use of mesenchymal stem cells (MSCs) found in the stromal vascular fraction (SVF) of equine adipose tissue has promising applications for regenerative therapies. The most commonly used source of equine adipose tissue is the subcutaneous tailhead. The objective of this study was to compare 3 adipose depot sites in horses and determine the viability and cellular yield, capillary density, gene expression for selected markers, and colony-forming unit fibroblasts (CFU-Fs) in adipose tissue taken from these sites. Adipose tissue was excised from the area lateral to the tailhead, the inguinal region,...
Little E, Yvorchuk-St Jean K, Little W, Sithole F, St Jean G.Oxybuprocaine hydrochloride ophthalmic solution has been widely used off-label in horses and donkeys, despite lack of data demonstrating efficacy and safety in these species. The objective of this study was to assess anesthetic efficacy of 0.4% oxybuprocaine hydrochloride ophthalmic solution in horses ( = 5) and donkeys ( = 24) and compare the effects with 0.5% proparacaine hydrochloride ophthalmic solution. The baseline corneal touch threshold (CTT) was measured with a Cochet-Bonnet esthesiometer. Donkeys ( = 12) and horses ( = 5) in group A received sterile ophthalmic solutions 0.4% oxybupro...
Willingham-Lane JM, Berghaus LJ, Giguère S, Hondalus MK.The soil-dwelling, saprophytic actinomycete is a multihost, facultative intracellular pathogen of macrophages. When inhaled by susceptible foals, it causes severe bronchopneumonia. It is also a pathogen of pigs, which may develop submaxillary lymphadenitis upon exposure. isolates obtained from foals and pigs possess conjugative plasmids housing a pathogenicity island (PAI) containing a novel family of genes of unknown function called the virulence-associated protein or family. The PAI regions of the equine and swine plasmids differ in gene composition, with equine isolates possessing six ...
Burkett BN, Thomason JM, Hurdle HM, Wills RW, Fontenot RL.Determine the effects of nonsteroidal anti-inflammatory drugs (NSAID) on platelet function and thromboxane synthesis immediately after drug administration and following 5 days of NSAID administration in healthy horses. Methods: Randomized cross-over study. Methods: Healthy adult horses (n=9; 6 geldings and 3 mares). Methods: Horses received either flunixin meglumine (1.1 mg/kg IV every 12 hours), phenylbutazone (2.2 mg/kg IV every 12 hours), or firocoxib (loading dose of 0.27 mg/kg IV on day 1, then 0.09 mg/kg IV every 24 hours for 4 days) for a total of 5 days. Blood samples were collected pr...
Olivera R, Moro LN, Jordan R, Luzzani C, Miriuka S, Radrizzani M, Donadeu FX, Vichera G.The demand for equine cloning as a tool to preserve high genetic value is growing worldwide; however, nuclear transfer efficiency is still very low. To address this issue, we first evaluated the effects of time from cell fusion to activation (<1h, n = 1261; 1-2h, n = 1773; 2-3h, n = 1647) on in vitro and in vivo development of equine embryos generated by cloning. Then, we evaluated the effects of using different nuclear donor cell types in two successive experiments: I) induced pluripotent stem cells (iPSCs) vs. adult fibroblasts (AF) fused to ooplasts injected with the pluripotency-inducin...
Garvican ER, Salavati M, Smith RKW, Dudhia J.The purpose of this study was to investigate the effect of normal synovial fluid (SF) on exposed endogenous tendon-derived cells (TDCs) and engrafted mesenchymal stem cells (MSCs) within the tendon extracellular matrix. Methods: Explants from equine superficial digital flexor (extra-synovial) and deep digital flexor tendons (DDFTs) from the compressed, intra-synovial and the tensile, extra-synovial regions were cultured in allogeneic or autologous SF-media. Human hamstring explants were cultured in allogeneic SF. Explant viability was assessed by staining. Proliferation of equine monolayer MSC...
Radakovic M, Davitkov D, Borozan S, Stojanovic S, Stevanovic J, Krstic V, Stanimirovic Z.The aim of this study was to determine the concentrations of oxidative stress parameters and DNA damage in horses infected by Theileria equi. Initial screening of 110 horses with duplex PCR enabled the selection of 30 infected horses with T. equi and 30 free of infection (control). Specimens from the 60 horses were further analysed by determining the following oxidative stress parameters: extent of haemolysis (EH), plasma free haemoglobin (PHb), catalase (CAT), Cu,Zn superoxide dismutase (SOD1), paraoxonase (PON1), nitrite (NO), total nitrate and nitrite (NOx), malondialdehyde (MDA) and free t...
Ojo KK, Dangoudoubiyam S, Verma SK, Scheele S, DeRocher AE, Yeargan M, Choi R, Smith TR, Rivas KL, Hulverson MA, Barrett LK, Fan E, Maly DJ....Sarcocystis neurona is the most frequent cause of equine protozoal myeloencephalitis, a debilitating neurological disease of horses that can be difficult to treat. We identified SnCDPK1, the S. neurona homologue of calcium-dependent protein kinase 1 (CDPK1), a validated drug target in Toxoplasma gondii. SnCDPK1 shares the glycine "gatekeeper" residue of the well-characterized T. gondii enzyme, which allows the latter to be targeted by bumped kinase inhibitors. This study presents detailed molecular and phenotypic evidence that SnCDPK1 can be targeted for rational drug development. Recombinant ...
Greppi MC, Guillot J, Melloul E, Bourdoiseau G, Lepage O, Cadoré JL.Guttural pouch mycosis (GPM) is a rare but potentially life-threatening condition in horses. GPM is caused by a fungal invasion into the mucosal lining of the guttural pouches and, frequently, the associated neurovascular structures. Although several species of fungi have been associated with this disease, Aspergillus spp. appear to be the most common isolated from the guttural pouches. However, it remains unclear which are the predisposing factors leading to the development of the infection. The objectives of the present study were to experimentally reproduce an infection by Aspergillus fumig...
Guan F, Robinson MA, Soma LR.Etanercept is a protein-based medication for the treatment of human patients with rheumatoid arthritis and other autoimmune-based diseases; its pharmacological action is to inhibit and antagonize tumour necrosis factor alpha. Etanercept was rumoured to be used in horse racing in North America. To detect such use, the aim of this study was to develop a liquid chromatography-mass spectrometry (LC-MS) method for confirmation of etanercept in equine plasma. Etanercept was extracted from plasma by anti-human IgG antibody linked to magnetic beads. The analyte was reduced and alkylated, and then dige...
Word TA, Larsen RW.Treatment of horse heart Cytochrome-c (Cc) with N-chloro-4-toluosulfonamide (Chloramine-t, CT) results in the oxidation of methionine (Met) residues to the corresponding sulfoxide including the distal heme ligand, Met80. The resulting Fe-sulfoxide coordination is sufficiently labile in the ferrous form to be displaced by gaseous ligands, including CO. Photolysis of the CO-CT-Cc complex provides an opportunity to examine ligand binding dynamics that are associated with a relatively rigid distal heme pocket. In this work, photoacoustic calorimetry (PAC) was utilized to obtain the kinetics as wel...
Caston SS, Schleining JA, Danielson JA, Kersh KD, Reinertson EL.To determine if instruction using simulated small intestine (SSI) is as effective as using cadaveric small intestine to teach the Gambee suture pattern to second year veterinary students. Methods: Prospective, randomized, blinded study. Methods: Second year veterinary students (n=59). Methods: Students were randomly assigned to groups using SSI or equine cadaver small intestine (CSI) to learn the Gambee suture pattern. The same educator, an experienced surgical instructor, instructed all students. Instruction consisted of verbal description of the technique with a schematic diagram followed by...
Looijen MG, New DJ, Fischer CD, Dardari R, Irwin KM, Berezowski CJ, Bond SL, Léguillette R.OBJECTIVE To evaluate the mRNA expression of T helper (Th)1, Th2, and Th17 cell-associated inflammatory mediators in cells of bronchoalveolar lavage fluid samples collected from healthy horses exposed to hyperbaric oxygen (HBO) and to monitor blood oxygen concentration during and following HBO therapy. ANIMALS 8 healthy horses. PROCEDURES In a randomized controlled crossover design study, each horse was exposed (beginning day 1) to 100% oxygen at a maximum of 3 atmospheres absolute (304 kPa) daily for 10 days or ambient air at atmospheric pressure in the HBO chamber for an equivalent amount of...
Maumus M, Roussignol G, Toupet K, Penarier G, Bentz I, Teixeira S, Oustric D, Jung M, Lepage O, Steinberg R, Jorgensen C, Noel D.Mesenchymal stem cells isolated from adipose tissue (ASC) have been shown to influence the course of osteoarthritis (OA) in different animal models and are promising in veterinary medicine for horses involved in competitive sport. The aim of this study was to characterize equine ASCs (eASCs) and investigate the role of interferon-gamma (IFNγ)-priming on their therapeutic effect in a murine model of OA, which could be relevant to equine OA. Methods: ASC were isolated from subcutaneous fat. Expression of specific markers was tested by cytometry and RT-qPCR. Differentiation potential was evaluat...
Curto E, Messenger KM, Salmon JH, Gilger BC.To determine whether horses with clinically diagnosed Equine Recurrent Uveitis (ERU) and those with Leptospirosis infection have a specific cytokine profile in their aqueous humor (AH) and serum that differs from horses with uveitis secondary to other ocular inflammatory processes and from horses with normal eyes. Methods: Twenty-five client-owned horses with uveitis that were presented to the North Carolina State University Ophthalmology Service, and four University-owned horses without history or clinical signs of ocular disease. Methods: Samples of AH and serum were obtained from horses wit...
Scharf A, Holmes SP, Thoresen M, Mumaw J, Stumpf A, Peroni J.Ultrasound-guided intralesional injection of mesenchymal stem cells (MSCs) is held as the benchmark for cell delivery in tendonitis. The primary objective of this study was to investigate the immediate cell distribution following intralesional injection of MSCs. Unilateral superficial digital flexor tendon (SDFT) lesions were created in the forelimb of six horses and injected with 10 × 10 MSCs labeled with superparamagnetic iron oxide nanoparticles (SPIOs) under ultrasound guidance. Assays were performed to confirm that there were no significant changes in cell viability, proliferation, migra...
de la Torre J, Sánchez-Martín P, Gosálvez J, Crespo F.Sperm quality was assessed in normozoospermic human (n = 10) and Spanish breed stallion (n = 10) after sperm fractionation during ejaculation. The first ejaculated fraction was separated from the second. A third sample was reconstituted using equivalent proportion of both fractions (RAW). Fraction 1, Fraction 2 and RAW semen were incubated for 30 min at 37°C to homogenise the impact of iatrogenic damage between both species. Sperm concentration, motility and sperm DNA damage were assessed in each fraction and RAW semen. The results showed two important facts: (i) spermatozoa confined at ...
Darnaud SJ, Southwood LL, Aceto HW, Stefanovski D, Tomassone L, Zarucco L.It is our clinical impression that age and incision length are more strongly associated with surgical site infection (SSI) following colic surgery than skin closure or wound protection method. Therefore, the objective of this observational clinical cohort study was to identify the risks for SSI in horses undergoing colic surgery. Data collection included pre-, intra-, and postoperative variables. Variables with P < 0.2 following univariable analysis were used in a logistic regression multivariable model. Variables with P <0.05 were included in the final model. Odds ratios (OR; 95% confid...
Epstein KL, Bergren A, Nie B, Arnold RD, Brainard BM.A lower molecular weight and molar substitution formulation (130/0.4) of hydroxyethyl starch solution has been shown to have a more sustained effect on COP and similar hemodynamic effects as a higher molecular weight and molar substitution formulation (600/0.75) in healthy horses. In humans, these pharmacodynamic characteristics are coupled with more rapid clearance and decreased adverse coagulation effects and accumulation. The objective of this study was to determine and compare the pharmacokinetics of these two formulations in horses. Eight healthy horses were given a 10 mL/kg bolus of eac...
Broeckx SY, Pille F, Buntinx S, Van Brantegem L, Duchateau L, Oosterlinck M, Chiers K, Bertone AL, Spaas JH, Martens AM.OBJECTIVE To evaluate lameness and morphological changes associated with an osteochondral fragment-groove procedure as a means of experimental induction of metacarpophalangeal (MCP) joint osteoarthritis within an 11-week period in horses. ANIMALS 6 nonlame adult warmbloods. PROCEDURES The right MCP joint of each horse underwent an osteochondral fragment-groove procedure (day 0). After 1 week of stall rest (ie, starting day 7), each horse was trained daily on a treadmill. Weekly, horses underwent visual and inertial sensor-based assessments of lameness. Both MCP joints were assessed radiographi...
Annandale EJ, Valberg SJ, Mickelson JR, Seaquist ER.Equine polysaccharide storage myopathy (PSSM) is an inherited disorder characterized by the accumulation of glycogen and abnormal polysaccharide in muscle with normal glyco(geno)lytic enzyme activities. The purpose of this study was to evaluate in vivo insulin sensitivity and glucose excursion in PSSM using a euglycemic hyperinsulinemic clamp. In addition, the content of muscle glucose transporters (GLUT1 and GLUT4) and the insulin receptor was determined in muscle biopsies using Western blot analysis. The glycogen content was 1.8-fold higher, and isolated polysaccharide analyzed by iodine abs...
Anderson GS, Belton P, Kleider N.Six horses severely affected by a seasonal dermatitis similar in both histopathology and epidemiology to Culicoides hypersensitivity (CH) and six unaffected or normal horses were inoculated intradermally with an extract of Culicoides obsoletus (Meigen), the most common Culicoides in southwestern British Columbia. Affected horses developed large welts within 20 min after injection, representing an immediate (type I) reaction; welts were largest 24 h or more after challenge, indicating in addition a delayed (type IV) reaction. This reaction was discernible for greater than 3 wk in some of the af...
Hamza E, Wagner B, Jungi TW, Mirkovitch J, Marti E.Insect bite hypersensitivity (IBH) is an allergic dermatitis of horses caused by IgE-mediated reactions to bites of insects of the genus Culicoides. IBH does not occur in Iceland due to the absence of Culicoides. However, Icelandic horses exported to mainland Europe as adults (1st generation) have a > or =50% incidence of developing IBH. In contrast, their progeny (2nd generation) has a <10% incidence of IBH. Here we show that peripheral blood mononuclear cells (PBMC) from Icelandic horses born in mainland Europe and belonging either to the IBH or healthy subgroup produce less interleukin (IL)...
Baker A, Plummer CE, Szabo NJ, Barrie KP, Brooks DE.To determine the concentration of doxycycline in preocular tear film following oral administration in horses as a possible therapeutic modality for infectious and keratomalacic equine keratitis. Methods: Eight broodmares without ocular disease from a Thoroughbred breeding facility were included in this study. Each mare received 20 mg/kg of doxycycline by mouth once daily in the morning for five consecutive days. Tears were collected 1 h after doxycycline administration starting on day one of administration and continuing for 10 consecutive days. Doxycycline levels in the tears were measured us...
Sweeney CR, Rossier Y, Ziemer EL, Lindborg SR.Bronchoalveolar lavage (BAL) was performed on 16 horses to determine whether it caused local or diffuse inflammation in the lungs. In 7 horses, BAL was performed in both lungs twice, 48 hours apart. Although total cell counts of the BAL samples did not change significantly, there were increased numbers and percentage of neutrophils in the second lavage fluid samples. In 5 horses, BAL was performed in 1 lung and repeated 48 hours later in the same lung and in the corresponding airway in the contralateral lung. The absolute cell count and percentage of neutrophils were significantly (P = < 0....
Hyde RM, Lynch TM, Clark CK, Slone DE, Hughes FE.This study investigated the influence of perfusate volume on antimicrobial concentration in synovial fluid following intravenous regional limb perfusion (IVRLP) and assessed the efficacy of low volume IVRLP. The front limbs of 9 horses were randomly assigned to 1 of 3 volume groups: 10 mL (Group 1), 30 mL (Group 2), or 60 mL (Group 3). A tourniquet was applied distal to the carpus and the limbs were perfused with 500 mg genta-micin diluted to the assigned volume via a catheter placed in the lateral palmar digital vein at the level of the proximal sesamoid bones. Synovial fluid samples were col...
Mumford JA, Wood JM, Folkers C, Schild GC.Thirty-one ponies immunized with inactivated virus vaccine containing A/equine/Miami/63 (H3N8) virus and six seronegative ponies were experimentally challenged with the homologous virus strain. All 6 unvaccinated ponies and 11 out of 31 vaccinated ponies became infected. A clear relationship between pre-challenge antibody, measured by single radial haemolysis (SRH), and protection was demonstrated as judged by virus excretion, febrile responses and antibody responses. Those ponies with SRH antibody levels greater than 74 mm2 were completely protected against challenge infection by the intranas...
Fiske-Jackson AR, Barker WH, Eliashar E, Foy K, Smith RK.The sensitivity of ultrasonography for the diagnosis of manica flexoria (MF) tears within the digital flexor tendon sheath (DFTS) is lower than for diagnosis of marginal tears of the deep digital flexor tendon (DDFT). Additional diagnostic tools would assist in appropriate decision making for either conservative or surgical management. Objective: To evaluate the improvement in lameness of horses with MF or DDFT tears following intrathecal analgesia and to assess the sensitivity and specificity of contrast radiography for the diagnosis of these tears. Methods: The case records of horses present...
Choi KS, Ko YJ, Nah JJ, Kim YJ, Kang SY, Yoon KJ, Joo YS.A rapid immunoassay for detecting and quantifying West Nile virus (WNV)-neutralizing antibodies in sera was developed as an alternative to the plaque reduction neutralization test (PRNT), the gold standard test for WNV. The assay is a competitive, enzyme-linked immunosorbent assay using neutralizing monoclonal antibody 5E8 (NT-ELISA). A cutoff percent inhibition (PI) value of 35% (mean PI plus 3 standard deviations), with a specificity of 99%, was established based on analysis of 246 serum samples from horses free of WNV. The NT-ELISA detected neutralizing antibodies in all sera collected 7 or...
French DA, Barber SM, Leach DH, Doige CE.Arthroscopic surgery was performed on 12 horses (2-4 years of age) to create a 7 x 14 mm full-thickness cartilage defect in one radial carpal bone and in the contralateral third carpal bone. Six horses remained confined to a small paddock and six horses underwent a program of increasing exercise consisting of walking, trotting, and cantering for 13 weeks. All lesions showed evidence of healing at week 6 that progressed to more complete healing at week 13. There was no difference in the amount of repair tissue covering the defect. Histologically, the lesions healed with a combination of fibrous...
Morton AJ, Campbell NB, Gayle JM, Redding WR, Blikslager AT.Synovitis in horses is frequently treated by administration of non-steroidal anti-inflammatory drugs (NSAIDs), which inhibit cyclooxygenase isoforms (COX-1 and COX-2). Constitutively expressed COX-1 is involved in physiologic functions such as maintenance of gastric mucosal integrity, whereas COX-2 is up-regulated at sites of inflammation. Thus, COX-2 inhibitors reduce inflammation with reduced gastrointestinal side effects as compared to non-selective COX inhibitors. The objective of the present study was to compare the anti-inflammatory effects of the preferential COX-2 inhibitor etodolac wi...
Moore JN, Norton N, Barton MH, Hurley DJ, Reber AJ, Donovan DC, Vandenplas ML, Parker TS, Levine DM.Endotoxaemia currently is associated with a poor prognosis in horses. The results of recent trials in other species indicate that phospholipid emulsions reduce the deleterious effects of endotoxin (LPS). However, in a previous study in horses, a 2 h infusion of emulsion caused an unacceptable degree of haemolysis. Objective: Rapid administration of a lower total dose of emulsion would reduce the effects of LPS and induce less haemolysis; the emulsion would reduce inflammatory effects of LPS in vitro. Methods: Twelve healthy horses received an i.v. infusion either of saline or a phospholipid em...
Valberg SJ, Velez-Irizarry D, Williams ZJ, Henry ML, Iglewski H, Herrick K, Fenger C.Certain Standardbred racehorses develop recurrent exertional rhabdomyolysis (RER-STD) for unknown reasons. We compared gluteal muscle histopathology and gene/protein expression between Standardbreds with a history of, but not currently experiencing rhabdomyolysis (N = 9), and race-trained controls (N = 7). Eight RER-STD had a few mature fibers with small internalized myonuclei, one out of nine had histologic evidence of regeneration and zero out of nine degeneration. However, RER-STD versus controls had 791/13,531 differentially expressed genes (DEG). The top three gene ontology (GO) enriched ...
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,...
Wilson TM, Ross PF, Owens DL, Rice LG, Green SA, Jenkins SJ, Nelson HA.An experiment to gain insight into the minimum toxic dose of fumonisins was conducted by feeding ponies rations with known fumonisin concentrations. Naturally contaminated corn screenings (CS) were blended with pellets, corn, and molasses to formulate individual daily diets. One group of 4 ponies was fed a ration with fumonisin B1 (FB1) varying from less than 1 ppm to 22 ppm. A second group of 5 ponies was fed a ration at varying rates containing 8 ppm FB1 for 180 days. A panel of clinical chemistry parameters was evaluated twice weekly for both groups. One pony in the first group died of equi...
Nikolakopoulos E, Watson ED.Bacteria were infused into the uteri of 5 estrous mares resistant to persistent mating-induced endometritis, first during a control cycle, and then during treatment with clenbuterol, a beta 2 agonist. Uterine cellular response was evaluated 48 h later by transrectal ultrasonography, followed by uterine lavage. During clenbuterol treatment all mares accumulated intrauterine fluid, whereas in the control cycle none of the mares retained fluid. There was no significant difference between the 2 cycles in the cloudiness of the lavage fluid, number of cells per milliliter, percentage of neutrophils ...
Stokes AM, Lavie NL, Keowen ML, Gaschen L, Gaschen FP, Barthel D, Andrews FM.This study investigated the use of a wireless ambulatory capsule (WAC; SmartPill(®) pH.p GI Monitoring System) to determine WAC-gastric emptying time (GET) in ponies. Objective: To measure WAC-GET and compare it to those findings with GET assessed by nuclear scintigraphy (S-GET). Objective: WAC-GET will be slower than S-GET, but will be significantly correlated. Methods: Seven healthy adult mixed-breed pony mares were used in this study. Feed was withheld for 12 h prior to the WAC administration. After administration, a complete-feed diet was fed to allow the WAC to pass into the stomach. Lum...
Heldens JG, Kersten AJ, Weststrate MW, van den Hoven R.An adjuvanted vaccine containing inactivated equine influenza, herpesvirus antigens, and tetanus toxoid was administered to young seronegative foals of 8 months of age by deep intramuscular injection in the neck (Group A). The first two vaccinations were given 4 weeks apart. The third was administered 6 months later. Another group of foals (Group B) was vaccinated according to the same scheme at the same time with monovalent equine herpes virus (EHV) vaccine (EHV1.4) vaccine. Antibody responses to the equine influenza (single radial haemolysis; SRH) and tetanus (ToBi ELISA) components of the v...
Ahn H, Kim J, Lee H, Lee E, Lee GS.Inflammasome, a cytosolic multi-protein complex, assembly is a response to sensing intracellular pathogenic and endogenic danger signals followed by caspase-1 activation, which maturates precursor cytokines such as interleukin (IL)-1β. Most inflammasome research has been undertaken in humans and rodents, and inflammasomes in veterinary species have not been well-characterized. In this study, we observed the effects of well-known inflammasome activators on equine peripheral blood monocytes (PBMCs). The NLRP3 inflammasome triggers include ATP, nigericin, aluminum crystals, and monosodium urate ...
Nevalainen M, Raulo SM, Brazil TJ, Pirie RS, Sorsa T, McGorum BC, Maisi P.We report the effects of mouldy hay/straw exposure, inhaled hay dust suspension (HDS) and inhaled lipopolysaccharide (LPS) on bronchoalveolar lavage fluid (BALF) gelatinolytic matrix metalloproteinase (MMP) levels and degree of activation in healthy (n = 6) and heaves- (previously termed chronic obstructive pulmonary disease) affected (n = 6 or 7) horses. Gelatinolytic MMPs in BALF were quantified by zymography, and gelatinases were shown by Western immunoblotting to be MMP-2 and MMP-9. Hay/straw and HDS challenges increased BALF total gelatinolytic activity only in heaves horses, with the maj...
Oreff GL, Dahan R, Tatz AJ, Raz T, Britzi M, Kelmer G.To determine the influence of 3 perfusate volumes on amikacin concentration in the metacarpophalangeal joint following cephalic regional limb perfusion (RLP) in standing horses. Methods: Seven healthy horses. Methods: Three perfusate volumes (100, 60, and 30 mL), containing 2 grams of amikacin, were tested during intravenous RLP at the cephalic vein, placing the tourniquet at mid antebrachium, in standing sedated horses. Synovial fluid was collected from the metacarpophalangeal joint before perfusion and at 30 and 120 minutes after perfusion. Serum samples were taken from the jugular vein at t...
Barton MH, Moore JN, Norton N.To evaluate the effect of pentoxifylline on response of horses to in vivo challenge exposure with endotoxin. Methods: 24 healthy horses in 3 treatment groups: pentoxifylline, endotoxin, or endotoxin and pentoxifylline. Methods: Horses of the pentoxifylline group were given a bolus of pentoxifylline (7.5 mg/kg of body weight, i.v.), followed by an infusion (3 mg/kg/h) over 3 hours, and those of the endotoxin group were given 20 ng of endotoxin/kg i.v. over 30 minutes. Those of the combination group were given both of the aforementioned compounds; pentoxifylline was administered immediately afte...
Kraus-Hansen AE, Fackelman GE, Becker C, Williams RM, Pipers FS.The vascular and microvascular anatomy of normal equine superficial digital flexor tendons was studied by dissection of vinyl-perfused specimens and by microangiography on high detail film. The presence of an extensive intratendinous vascular latticework was confirmed, and a 'nutrient artery' described closely associated with the accessory ligament of the superficial digital flexor tendon (proximal check ligament). Circumferential stripping of the paratenon from the tendon to eliminate afferent vessels was performed bilaterally in three horses and unilaterally in a fourth, followed by a treadm...
Brandão JS, Alvarenga ML, Pfeifer JPH, Dos Santos VH, Fonseca-Alves CE, Rodrigues M, Laufer-Amorim R, Castillo JAL, Alves ALG.The superficial digital flexor tendon (SDFT) is a structure frequently affected by injuries in high-performance athletic horses, and there are limited therapeutic options. Regenerative medicine has evolved significantly in treating different illnesses. However, understanding the cellular behaviour during mesenchymal stem cell (MSC) transplantation in healthy tissues is not fully known yet. To address the inflammatory response induced by allogeneic MSC transplantation, this study evaluated the local inflammatory response after the application of allogeneic adipose tissue-derived mesenchymal ste...
Norris JW, Pratt SM, Auh JH, Wilson SJ, Clutter D, Magdesian KG, Ferraro GL, Tablin F.Bleeding in racing horses associated with exercise appears to be multifactorial, and clinical investigation into severe cases rarely occurs. Previously, we reported a severe bleeding diathesis in a Thoroughbred mare. Herein, we describe the cellular physiology of this defect, provide a diagnostic tool for identifying it, and demonstrate that the dysfunction is heritable. Objective: The subject has a heritable defect in platelet secretion that reduces thrombin generation in the absence of additional plasma factors and delays the onset of thrombin production even in the presence of these factors...
Rols MP, Tamzali Y, Teissié J.Sarcoids are skin spontaneous tumours detected in horses. It can be cured by chemotherapy by using cisplatin. A multisequence treatment must be performed. Problems are present due to the poor diffusion of the hydrophilic product in the tumours. Electropulsation is known to drastically enhance the effect of antitumoral drugs in vivo. Taking into account the very successful results of the group in Ljubljana (Slovenia), we started a research clinical program where electropulsation was applied after local cisplatin injection. The size of sarcoids is large (several centimeters). A specially designe...
Metzger J, Gast AC, Schrimpf R, Rau J, Eikelberg D, Beineke A, Hellige M, Distl O.The Miniature Shetland pony represents a horse breed with an extremely small body size. Clinical examination of a dwarf Miniature Shetland pony revealed a lowered size at the withers, malformed skull and brachygnathia superior. Computed tomography (CT) showed a shortened maxilla and a cleft of the hard and soft palate which protruded into the nasal passage leading to breathing difficulties. Pathological examination confirmed these findings but did not reveal histopathological signs of premature ossification in limbs or cranial sutures. Whole-genome sequencing of this dwarf Miniature Shetland p...
Ledbetter EC, Scarlett JM.To describe morphologic features, pachymetry and endothelial cell density of the normal equine cornea and limbus by in vivo confocal microscopy. Methods: Ten horses without ocular disease. Methods: The central and peripheral corneas were examined with a modified Heidelberg Retina Tomograph II and Rostock Cornea Module using a combination of automated and manual image acquisition modes. Thickness measurements of various corneal layers were performed and endothelial cell density determined. Results: Images of the constituent cellular and noncellular elements of the corneal epithelium, stroma, en...
Rings LM, Swink JM, Dunbar LK, Burns TA, Toribio RE.The enteroinsular axis (EIA) comprises intestinal factors (incretins) that stimulate insulin release after PO ingestion of nutrients. Glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) are the main incretins. The EIA has not been investigated in healthy neonatal foals but should be important because energy demands are high in healthy foals and dysregulation is frequent in sick foals. Objective: To evaluate the EIA response to carbohydrates or fasting in newborn foals. We hypothesized that incretin secretion would be higher after PO versus IV carbohydrate adm...
