Experimental methods in equine research encompass a variety of techniques and procedures used to investigate physiological, behavioral, and health-related aspects of horses. These methods are designed to collect data that can enhance the understanding of equine biology and inform veterinary practices. Common experimental approaches include controlled trials, observational studies, and laboratory-based experiments. Techniques may involve the use of non-invasive imaging, biochemical assays, and physiological monitoring to assess parameters such as metabolic function, locomotion, and disease progression. This page compiles peer-reviewed research studies and scholarly articles that explore the application, development, and evaluation of experimental methods in the study of equine science.
Mead DG, Ramberg FB, Maré CJ.In previous experiments we have demonstrated that colonized and wild black flies are competent laboratory vectors of different Mexican and Western USA isolates of vesicular stomatitis virus, serotype New Jersey (VSV-NJ). We have recently demonstrated biological VSV-NJ transmission by black flies using animal models. In the study described here, we tested the vector competence of colonized and wild black flies for the vesicular stomatitis virus, serotype Indiana (VSV-IN). A 1998 equine isolate was used. After a 10 day incubation period, saliva from experimentally infected Simulium vittatum and ...
Pérez R, Cabezas I, Sutra JF, Galtier P, Alvinerie M.A study was undertaken to evaluate and compare faecal excretion of moxidectin and ivermectin in horses after oral administration of commercially available preparations. Ten clinically healthy adult horses, weighing 390-446 kg body weight (b.w.), were allocated to two experimental groups. Group I was treated with an oral gel formulation of moxidectin at the manufacturer's recommended therapeutic dose of 0.4 mg/kg b.w. Group II was treated with an oral paste formulation of ivermectin at the recommended dose of 0.2 mg/kg b.w. Faecal samples were collected at different times between 1 and 75 days ...
Powell DM, Lawrence LM, Fitzgerald BP, Danielsen K, Parker A, Siciliano P, Crum A.The metabolic effects of short-term feed restriction and dietary calorie source were studied in horses receiving high-roughage or high-concentrate diets. Four Thoroughbred geldings were assigned to four treatment groups in a 4 x 4 Latin square experiment. The four treatments were 1) a nutritionally adequate high-roughage ration (70% roughage, 30% concentrate; AHR), 2) a nutritionally adequate high-concentrate ration (40% roughage, 60% concentrate; AHC), 3) 70% of the intake of the AHR diet (RHR), and 4) 70% of the intake of the AHC diet (RHC). Diets AHR and AHC were designed to meet the calori...
Bulone V, Rademaker GJ, Pergantis S, Krogstad-Johnsen T, Smestad-Paulsen B, Thomas-Oates J.Separation of horse dander allergens using two-dimensional PAGE resulted in the identification of 16 proteins that react with allergic patient sera. A sensitive method has been developed for analysing the structures of the glycan chains of individual glycoprotein allergens transferred to blots following two-dimensional PAGE, and has allowed the structural identification of the glycan chains of the most abundant isoforms of Equ c 1, a glycosylated horse dander major allergen. The method involves separation of the allergens by two-dimensional PAGE, transfer to polyvinylidene difluoride membranes...
Murphy DJ, Todhunter RJ, Fubini SL, Vernier-Singer M, Straubinger RK, Lust G.To study in vitro (1) the dose-response relationships between proteoglycan metabolism in normal and corticosteroid-treated articular cartilage; (2) long-term proteoglycan metabolism after treatment of articular cartilage with corticosteroids; and (3) the effect of corticosteroids on proteoglycan metabolism in articular cartilage treated with monocyte-conditioned medium (MCM). Methods: Equine and canine articular cartilage explants were treated with corticosteroids and MCM. Proteoglycan synthesis and degradation were measured by radioactive labeling in short-term culture, and the long-term effe...
Alvarenga MA, Landim-Alvarenga FC, Moreira RM, Cesarino MM.The present experiments aimed to examine the substitution of glycerol (G) by ethylene glycol (E) as a cryoprotective agent for stallion spermatozoa. Two different ethylene glycol concentrations (5% and 10%) and also the association of glycerol (2%) and ethylene glycol (3%) (E/G) were studied (Experiment 1). In Experiment 2, two packing systems (0.5 x 4.0 ml) were evaluated using both cryoprotectors. In both experiments, the sperm membrane integrity after freezing was evaluated using transmission electron microscopy. The mean post-thaw motility was 34.25, 36.5, 29.25 and 34.75% for G5%, E5%, E1...
Fenton JI, Chlebek-Brown KA, Peters TL, Caron JP, Orth MW.To determine whether glucosamine-3-sulfate, glucose-3-sulfate (control) and N-acetyl glucosamine inhibit experimentally induced degradation of equine articular cartilage explants similar to glucosamine HCl. Methods: Articular cartilage was obtained from the antebrachio-carpal and middle joints of horses (2-8 years old) killed for reasons unrelated to lameness. Cartilage discs were harvested from the weight-bearing region of the articular surface and cultured. Media were exchanged daily and the recovered media stored at 4 degrees C. On days 1 and 2 lipopolysaccharide (LPS, 10 microg/ml) was add...
Hahn CN, Mayhew IG.The precise appearance of ptosis due to lesions at different sites was investigated in experimental ponies. The angles of the eyelashes to the head was used as an objective measurement of ptosis after local anaesthesia of the sympathetic trunk or the palpebral nerve and the administration of an ocular alpha agonist or antagonist. It was shown that ptosis is not an inevitable consequence of palpebral nerve pathology, that ocular alpha antagonists can induce ptosis, and that alpha agonist eyedrops have an inconsistent effect on the equine pupil, but are consistent at reversing ptosis induced by ...
Gilger BC, Malok E, Stewart T, Horohov D, Ashton P, Smith T, Jaffe GJ, Allen JB.The purpose of this study was to determine the effects of an intravitreal device releasing cyclosporine A (CsA) on recurrent inflammatory episodes in experimental uveitis. Nine normal horses were immunized peripherally with H37RA-mTB antigen twice, and then received 25 microg of H37RA-mTB antigen intravitreally in the right eye and an equal volume of balanced salt solution intravitreally in the left eye. Two weeks later, the animals randomly received either a CsA or a polymer implant (without CsA) in both eyes 1 week following implantation of the devices, 25 microg of H37RA-mTB antigen was rei...
Morisset S, McClure SR, Hillberry BM, Fisher KE.To compare the in vitro holding power and associated microstructural damage of 2 large-animal centrally threaded positive-profile transfixation pins in the diaphysis of the equine third metacarpal bone. Methods: 25 pairs of adult equine cadaver metacarpal bones. Methods: Centrally threaded positive-profile transfixation pins of 2 different designs (ie, self-drilling, self-tapping [SDST] vs nonself-drilling, nonself-tapping [NDNT] transfixation pins) were inserted into the middiaphysis of adult equine metacarpal bones. Temperature of the hardware was measured during each step of insertion with ...
Byrne KM, Vierck J, Dodson MV.Equine satellite cells are responsible for muscle healing and regeneration in the mature horse. We describe the in vitro cell culture conditions required for clonal populations of equine satellite cells to undergo both proliferation and differentiation. Our hypothesis is that these in vitro conditions model regeneration of muscle and can be used to evaluate potential therapeutics. In this study, 2 areas of satellite cell response were tested: proliferation of clones induced by growth factors, and fusion induced by culture conditions. Equine satellite cell clones showed differences in their res...
Miyashita Y, Nakajima S, Imada H.Three horses were trained with a discrimination task in which the color (blue or yellow) of a center panel signaled the correct (left or right) response (lever press). Reinforcing outcomes for the two correct color-position combinations (blue-left and yellow-right) were varied across phases. Discrimination performance was better when the combinations were differentially reinforced by two types of food (chopped carrot pieces and a solid food pellet) than when the combinations were randomly reinforced by these outcomes or when there was a common reinforcer for each of the correct combinations. H...
Moncayo AC, Edman JD, Turell MJ.The effect of eastern equine encephalomyelitis (EEE) virus on the survivorship of Aedes albopictus (Skuse), Anopheles quadrimaculatus Say, and Coquillettidia perturbans (Walker) was determined experimentally. Female mosquitoes were allowed to feed on EEE viremic chicks, and survival rates were compared for infected and uninfected mosquitoes. Additionally, the survival of female Cq. perturbans and An. quadrimaculatus intrathoracically (i.t.) inoculated with EEE was compared with controls receiving diluent inoculations. Infection with EEE significantly reduced survival in Cq. perturbans compared...
Bice DE, Seagrave J, Green FH.Asthma is now recognized to be a chronic inflammatory disease that affects the whole lung. Incidence appears to be increasing despite improved treatment regimens. There is substantial epidemiological evidence suggesting a relationship between the incidence and severity of asthma (e.g., hospitalizations) and exposure to increased levels of air pollution, especially fine and ultrafine particulate material, in susceptible individuals. There have been a few studies in animal models that support this concept, but additional animal studies to test this hypothesis are needed. However, such studies mu...
Worster AA, Nixon AJ, Brower-Toland BD, Williams J.To determine the morphologic and phenotypic effects of transforming growth factor beta1 (TGFbeta1) on cultured equine mesenchymal stem cells (MSC) and articular chondrocytes. Methods: Bone marrow aspirates and articular cartilage samples from a 2-year-old and two 8-month-old horses. Methods: After initial isolation and culture, MSC and chondrocytes were cultured in Ham's F-12 medium supplemented with TGF-beta1 at a concentration of 0, 1, 5, or 10 ng/ml. Medium was exchanged on day 2, and cells were harvested on day 4. Medium was assayed for proteoglycan (PG) content. Total RNA was isolated fro...
Vahlenkamp TW, Enbergs HK, Müller H.Cells of the peripheral blood of experimentally and naturally borna disease virus (BDV)-infected animals and of human psychiatric patients and healthy individuals were analyzed for the presence of viral RNA using a BDV-p40-specific nested reverse transcription-polymerase chain reaction (RT-PCR). The assay proved to be highly sensitive as 10 RNA molecules were reproducibly amplified. BDV RNA was detected in blood cells of experimentally infected immunocompetent mice and rats. Mice were persistently infected without showing clinical signs of borna disease (BD), whereas the rats suffered from acu...
Lindsay DS, Dubey JP, Kennedy TJ.The present study examined the efficacy of ponazuril in inhibiting merozoite production of Sarcocystis neurona in cell cultures. Ponazuril inhibited merozoite production by more that 90% in cultures of S. neurona treated with 1.0 microg/ml ponazuril and greater than 95% inhibition of merozoite production was observed when infected cultures were treated with 5.0 microg/ml ponazuril. Ponazuril may have promise as a therapeutic agent in the treatment of S. neurona induced equine protozoal myeloencephalitis (EPM) in horses.
Lindsay DS, Dykstra CC, Williams A, Spencer JA, Lenz SD, Palma K, Dubey JP, Blagburn BL.Equine protozoal myeloencephalitis (EPM) is a neurologic syndrome in horses from the Americas and is usually caused by infection with the apicomplexan parasite, Sarcocystis neurona. A horse model of EPM is needed to test the efficacy of chemotherapeutic agents and potential vaccines. Five horses that were negative for antibodies to S. neurona in their serum and cerebrospinal fluid (CSF) were injected in the subarachnoid space with living merozoites of the SN2 isolate of S. neurona. None of the horses developed clinical disease or died over a 132-day observation period. All five horses develope...
Walsh CP, Duncan RB, Zajac AM, Blagburn BL, Lindsay DS.Neospora hughesi is a recently described cause of equine protozoal myeloencephalitis (EPM). A rodent model for pathogenicity would facilitate development of therapies to be used in horses. In the present study, we examined the susceptibility of BALB/c gamma-interferon gene knockout (gamma-INFKO), BALB/c, CD-1, and C57BL/6 strains of mice and gerbils to infection with tachyzoites of the Nh-A1 strain of N. hughesi isolated from a horse from AL, USA. Only the gamma-IFNKO mice developed severe clinical disease following infection with N. hughesi and died 19-25 days after infection and exhibited se...
Woodie JB, Ruggles AJ, Litsky AS.To evaluate 2 methods of midbody proximal sesamoid bone repair--fixation by a screw placed in lag fashion and circumferential wire fixation--by comparing yield load and the adjacent soft-tissue strain during monotonic loading. Methods: Experimental study. Methods: 10 paired equine cadaver forelimbs from race-trained horses. Methods: A transverse midbody osteotomy of the medial proximal sesamoid bone (PSB) was created. The osteotomy was repaired with a 4.5-mm cortex bone screw placed in lag fashion or a 1.25-mm circumferential wire. The limbs were instrumented with differential variable relucta...
Jansson N, Ducharme NG, Hackett RP, Mohammed HO.To examine the effect of cordopexy, laryngoplasty, and cordopexy combined with a modified laryngoplasty on airway mechanics. Methods: Experimental airway mechanics were determined by subjecting equine cadaveric larynges to airflows similar to inspiratory airflow of exercising horses. Methods: Twenty equine larynges. Methods: Using cadaveric larynges, we developed and tested a new technique of arytenoid cartilage abduction. All larynges had the right arytenoid cartilage abducted to mimic the degree of arytenoid abduction that occurs at maximal exertion in live horses. Three surgical techniques ...
Fenton JI, Chlebek-Brown KA, Peters TL, Caron JP, Orth MW.Objective To determine whether glucosamine inhibits experimentally induced degradation of equine articular cartilage explants. Methods Articular cartilage was obtained from the antebrachio-carpal and middle joints of horses (2-8 years old) killed for reasons unrelated to lameness. Cartilage discs were harvested from the weight-bearing region of the articular surface and cultured. Media were exchanged daily and the recovered media stored at 4 degrees C. Explants were maintained in basal media 2 days prior to the start of four treatment days. On days 1-4 lipopolysaccharide (LPS, 10 microg/ml) or...
Brinsko SP, Rowan KR, Varner DD, Blanchard TL.This study was conducted to compare the cooling rates and storage temperatures within equine semen transport containers exposed to different ambient temperatures, and to evaluate the ability of these containers to preserve spermatozoal motility following 24 h of storage under these conditions. In Experiment 1, nonfat dried milk solids, glucose, sucrose, equine semen extender was divided into seven 40-mL aliquots and loaded into seven different semen transport containers: Equitainer I, Equitainer II, Equitainer III, ExpectaFoal, Bio-Flite, Lane STS, and Equine Express. After containers were loa...
Fitzgerald BP, Davison LA, McManus CJ.In seasonally breeding species photoperiodic information is thought to be conveyed to the reproductive and prolactin axis via changes in circulating concentrations of melatonin. For some species, a constant melatonin stimulus is perceived as a short day, whereas in others no photoperiodic information is provided. In the mare, a preliminary study demonstrated that constant administration of melatonin did not modify prolactin secretion, suggesting that this treatment regimen failed to provide photoperiodic information. To further investigate this proposal and to investigate an alternative explan...
Hudson NP, Pearson GT, Mayhew IG.Ileal samples were harvested fresh from euthanized adult horses. The tissues were microdissected to prepare wholemount preparations for immunohistochemistry and for either explant or dissociated culture systems of the enteric nervous system. Explant culture systems were established using whole-mounts of either the submucous plexus or the muscularis externa (including the myenteric plexus). Dissociated cell cultures could only be obtained from the submucous plexus. Culture systems were maintained for up to 5 days. Immunoreactivity for a neuronal marker (Pan-N) and for glial cell markers (GFAP a...
Degueurce C, Chateau H, Pasqui-Boutard V, Pourcelot P, Audigié F, Crevier-Denoix N, Jerbi H, Geiger D, Denoix JM.A method is detailed allowing the computation of three-dimensional (3D) joint angles. Each joint of the equine digit is modelled as a sequence of three single axis rotary joints. The Joint Coordinate System was used; it involves a specific sequence of cardanic angles. The decomposition of the angles was chosen so that the three elementary angles coincide with the flexion/extension, passive abduction/adduction and lateral/medial rotations. The algorithms and kinematic procedures were described for the equine front digital joints. This method was tested in vitro on four forelimbs. For each limb,...
Hammond SA, Li F, McKeon BM, Cook SJ, Issel CJ, Montelaro RC.Persistent infection of equids by equine infectious anemia virus (EIAV) is typically characterized by a progression during the first year postinfection from chronic disease with recurring disease cycles to a long-term asymptomatic infection that is maintained indefinitely. The goal of the current study was to perform a comprehensive longitudinal analysis of the course of virus infection and development of host immunity in experimentally infected horses as they progressed from chronic disease to long-term inapparent carriage. We previously described the evolution of EIAV genomic quasispecies (C...
Vanderwall DK, Betschart RW, Squires EL.The objective of this study was to determine if the primary circulating metabolite of PGF2alpha, 13,14-dihydro-15-keto-PGF2alpha (PGFM), is biologically active and would induce luteolysis in nonpregnant mares. On Day 9 after ovulation, mares (n = 7/group) were randomly assigned to receive: 1) saline control, 2) 10 mg PGF2alpha or 3) 10 mg PGFM in 5 mL 0.9% sterile saline i.m. On Days 0 through 16, blood was collected for progesterone analysis. In addition, blood was collected immediately prior to treatment, hourly for 6 h, and then at 12 and 24 h after treatment for progesterone and PGFM analy...
Okumura M, Fujinaga T.The role of keratan sulphate (KS) as a metabolic marker of cartilage was evaluated using an in vitro model of equine articular cartilage. Articular cartilage was harvested from clinically healthy 6-month-old foals (n = 3). Chondrocytes were centrifuged and cultured as pellets. Chondrocyte pellets were stimulated by insulin-like growth factor-I alpha (IGF-I alpha) or interleukin-1 alpha (IL-1 alpha) for 2 weeks. The concentrations of sulphated glycosaminoglycans (GAG) and KS in the culture media were measured by a 1,9-dimethyl-methylene blue (DMMB) colorimetric assay and an inhibition enzyme-li...
Boorman S, Hanson RR, Velloso Alvarez A, Zhong K, Hofmeister E, Boone LH.To determine the effect of concurrent versus delayed treatment with corticosteroid on equine articular tissues also treated with local anesthetic in vitro in the presence of inflammatory mediators. Methods: Controlled laboratory study. Methods: Five geldings, one mare (aged 3-18 years). Methods: From each horse, 24 synovial and 12 osteochondral explants were cultured in a 12-well plate (2 wells/group, 2 synovial and 1 osteochondral explant/well, total 216 explants in the study). Explants were stimulated in culture medium with 10 μg/ml recombinant equine interleukin-1β and 10 μg/ml tumor...
Käser R, Bruckmaier RM, Thomas S, Sieme H, Wedekind C, Burger D.Oxytocin is a hormone that may not only influence reproductive mechanisms in mammals but also their social behavior, including pair bonding. We therefore tested if the concentrations of oxytocin and other hormones reveal mate preferences of 13 mares in estrus. Each mare was first exposed to two stallions (haphazardly selected out of seven) and her behavior recorded. The mare was then returned to her box (i.e., no contact to stallions during that time). Approximately 4.5 hours later, venous blood samples were collected every minute during 30 minutes preceding exposure to one of the two previo...
Mason DE, Muir WW, Olson LE.Smooth muscle strips from the midcervical portion of the trachea and bronchial smooth muscle strips from third-generation airways of horses were placed in tissue baths, and isometric contractile force was measured. Active force was measured in response to electrical stimulation and exogenous acetylcholine. Square-wave electrical stimuli were applied at various voltages (10, 12, 15, 18, 20, 25 V), frequencies (3, 5, 10, 15, 20, 25, 30 Hz), and pulse durations (0.2, 0.5, 1.0, 1.5, 2.0 ms). Isometric contractile force increased as voltage, frequency, and pulse duration increased. Maximal contract...
Dart A, Tee E, Brennan M, Dart C, Perkins N, Chapman S, Debney S.To assess the effect of 1 or 2 laryngeal prosthetic sutures on rima glottidis areas in equine laryngeal specimens. Methods: Experimental, randomized design. Methods: Cadaveric equine larynges (n=16). Methods: Larynges were collected from 10 horses; 2 sutures each were preplaced in the right and left sides of each larynx. A dorsal suture (DS) was placed through the caudal rim of the dorsal midline of the cricoid cartilage, under the cricopharyngeus muscle and through the proximal and rostral aspect of the muscular process. A lateral suture (LS) was placed 1.5 cm lateral to the DS and through th...
Otten N, Marti E, Söderström C, Amtmann E, Burger D, Gerber H, Lazary S.A xanthate compound with antiviral and antitumoural activities, tricyclodecan-9-yl-xanthogenate (D609) in combination with the potassium salt of the lauric acid (KC12) and, in a further investigation, the above-mentioned substances together with recombinant human TNF alpha (rh-TNF alpha), were tested on equine sarcoid tumours for therapeutic efficacy. A pilot investigation on 5 healthy horses showed that the compounds were well-tolerated; apart from a local, temporary oedema at the injection site, no other clinical symptoms were observed after subcutaneous administration of volumes from 0.1 to...
Murakami K, Sentsui H, Shibahara T, Yokoyama T.Three horses were experimentally infected with equine infectious anemia virus (EIAV). All horses were febrile after inoculation with EIAV and then developed chronic symptoms with intermittent fever. The febrile period was characterized by a rise in body temperature with reduced PBL and erythrocyte counts. Flow cytometric analysis showed that the reduced number of lymphocytes was due to significant decreases in CD4+ and CD8+ T cells in the absence of any change in B cell number. At the end of the febrile period the body temperature began to recover and numbers of CD4+ and CD8+ T cells showed a ...
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...
Rankins EM, Salem K, Manso Filho HC, Malinowski K, McKeever KH.Clenbuterol (β agonist) is a commonly administered bronchodilator in race and performance horses. While long-term administration can alter exercise performance and muscle properties, little is known about its effects on these parameters following short-term administration. A single dose of clenbuterol (0.80 µg/kg) was expected to alter muscle activity of the extensor carpi radialis, semitendinosus, and longissimus dorsi during submaximal exercise. Eight mature Standardbred horses exercised for 2 minutes at 5 m/s on a high-speed treadmill following clenbuterol dosing (clenbuterol) or no dosin...
Derksen FJ, Slocombe RF, Gray PR, Robinson NE.The lungs of sensitized horses were exposed to aerosolized ovalbumin. Some horses (n = 4) were given ovalbumin in 1 lung only, whereas in others (n = 7), ovalbumin or vehicle were inoculated in the cranial, ventral, and caudal regions of the caudal lung lobe. Horses were exercised 5 hours after ovalbumin exposure. Immediately before exercise, endoscopy failed to reveal any abnormality. After exercise, endoscopic examination of horses subjected to unilateral ovalbumin exposure revealed extensive blood in airways leading to the exposed lung in all horses. Blood was not observed in the airways le...
Vercelli C, Tursi M, Miretti S, Giusto G, Gandini M, Re G, Valle E.Laminitis is one of the most devastating diseases in equine medicine, and although several etiopathogenetic mechanisms have been proposed, few clear answers have been identified to date. Several lines of evidence point towards its underlying pathology as being metabolism-related. In the carbonyl stress pathway, sugars are converted to methylglyoxal (MG)-a highly reactive α-oxoaldehyde, mainly derived during glycolysis in eukaryotic cells from the triose phosphates: D-glyceraldehyde-3-phosphate and dihydroxyacetone phosphate. One common hypothesis is that MG could be synthesized during the dig...
Karasiewicz J, Andrzej-Modlinski J.Our Department of Experimental Embryology originated from The Laboratory of Embryo Biotechnology, which was organized and directed by Dr. Maria Czlonkowska until her premature death in 1991. Proving successful international transfer of frozen equine embryos and generation of an embryonic sheep-goat chimaera surviving ten years were outstanding achievements of her term. In the 1990s, we produced advanced fetuses of mice after reconstructing enucleated oocytes with embryonic stem (ES) cells, as well as mice originating entirely from ES cells by substitution of the inner cell mass with ES cells. ...
Bischofberger AS, Wereszka MM, Hadidane I, Perkins NR, Jeffcott LB, Dart AJ.To evaluate the effect of 3 laryngeal prostheses alone or in combination on rima glottidis area in horses. Methods: Experimental randomized design. Methods: Cadaveric equine larynges (n = 22). Methods: Three prostheses were preplaced in each of 14 larynges. Rima glottidis area was measured after loading each suture in 5 Newton (N) increments from 0 N to 35 N. In 8 larynges, the 3 prostheses were tied alone or in combination at a fixed load of 15 N and rima glottidis area measured. Results: Rima glottidis cross-sectional area increased as the load on each prosthesis increased with maximum area ...
Gudehus T, Sod GA, Riggs LM, Mitchell CF, Martin GS.To compare the mean number of cycles to failure under axial compression of equine proximal interphalangeal (PIP) joint arthrodesis constructs created by 2 parallel transarticular Acutrak Plus screws (AP-TS) or 2 parallel transarticular 5.5 mm cortical screws inserted in lag fashion (AO-TLS). Methods: Paired in vitro biomechanical testing of 2 methods of stabilizing cadaveric adult equine forelimb PIP joints. Methods: Cadaveric adult equine forelimbs (n=5 pairs). Methods: For each forelimb pair, 1 PIP joint was stabilized with AP-TS and 1 with AP-TLS. The 5 construct pairs were tested for cycli...
Halsberghe BT.Hoof problems are commonly seen in veterinary practice and manipulation of hoof growth rate can be practical and beneficial for that matter. The purpose of this research was to evaluate the effect of whole body vibration (WBV) on hoof growth rate of front feet in the horse. The study was an experimental, single subject, repeated measure design, with all horses serving as control and treatment. Ten horses were subject to WBV, 30 min, twice daily, five days a week, for 60 days in addition to their regular exercise routine. Hoof growth was measured from the reference hairline down to a horizo...
Todhunter RJ, Fubini SL, Vernier-Singer M, Wootton JA, Lust G, Freeman KP, MacLeod JN.To determine how acute synovitis, with and without intra-articular methylprednisolone acetate (MPA), affect synthesis of proteoglycan, total protein, and collagen in articular cartilage and total protein synthesis in synovial membrane. Methods: Synovitis was induced in 10 ponies by the injection of 0.5 ng lipopolysaccharide (LPS) into the left radiocarpal and midcarpal joints every 2 days for a total of four treatments. Synovitis was documented by clinical examination and synovial fluid analyses. Two days before euthanasia, MPA (0.1 mg/kg) was injected with the last dose of LPS into both the l...
DiPietro JA, Lock TF, Todd KS, Sanecki RK.A controlled test was carried out on 15 pony foals inoculated with 1,500 +/- 108.8 infective Parascaris equorum eggs. The foals were assigned to 3 treatment groups. Treatments given on postinoculation day 11 included 0.2 mg of ivermectin/kg of body weight, formulated as paste (n = 5), or liquid (n = 5), or no treatment (controls; n = 5). The foals were euthanatized on postinoculation day 25, and examined for larvae in the small intestine, lungs, and liver. Larvae were not found in foals treated with ivermectin liquid or paste, whereas significantly (P less than 0.05) higher mean numbers (960.9...
Zoppa AL, Santoni B, Puttlitz CM, Cochran K, Hendrickson DA.To compare the biomechanical characteristics of 2 arthrodesis techniques for the equine proximal interphalangeal joint (PIP) using either a 3-hole 4.5 mm locking compression plate (LCP) or 3-hole 4.5 mm narrow dynamic compression plate (DCP), both with 2 transarticular 5.5 mm cortex screws. Methods: Experimental. Methods: Cadaveric adult equine forelimbs (*n=6 pairs). Methods: For each forelimb pair, 1 limb was randomly assigned to 1 of 2 treatment groups and the contralateral limb by default to the other treatment group. Construct stiffness, gap formation across the PIP joint, and rotation ab...
Alexander GR, Gibson KT, Day RE, Robertson ID.To measure the effects of transection of the accessory ligament of the superficial digital flexor (SDF) muscle (superior check desmotomy) on flexor tendon and suspensory ligament (SL) strain in vitro. Methods: In vitro experimental biomechanical investigation. ANIMALS USED: Ten equine cadaver forelimbs. Methods: The effects of superior check desmotomy were determined using equine cadaver forelimbs secured in a servocontrolled hydraulic testing machine. Strain sensors were used to measure strain on the superficial and deep digital flexor tendons and SL, and a goniometer was used to measure join...
Rijkenhuizen AB, Németh F, Dik KJ, Goedegebuure SA, Van de Brom WE.The clinical, radiographic, arteriographic, scintigraphic and histological effects of experimental occlusion of the Ramus navicularis (R. Navicularis) and its branching arteries are evaluated. Occlusion of the R. navicularis and its branching arteries creates changes, arteriographically and histologically, which resemble those of navicular disease. The increased bone remodelling, the shift in arterial pattern, the formation of collaterals and the increased connective tissue in the synovial membrane and nutrient foramina, as a reaction to the reduction of the distal arterial supply of the navic...
Bayly WM, Slocombe RF.Effects of respiratory tract obstructions on ventilatory mechanics in horses exercising at high speeds were tested with a fibreglass replica of the airways (nares to mainstem bronchi) of an adult horse. Segmental pressures were recorded at six sites along the model at four different unidirectional flows (1300-4100 litre min-1), and the respective resistances (R) to airflow were calculated. The external nares and the larynx made the greatest contributions to the total resistance (RTOT) when no obstruction was present. Modifying the model to simulate severe pharyngeal lymphoid hyperplasia (PLH) ...
Derrick D, Gick B.During locomotion, humans switch gaits from walking to running, and horses from walking to trotting to cantering to galloping, as they increase their movement rate. It is unknown whether gait change leading to a wider movement rate range is limited to locomotive-type behaviours, or instead is a general property of any rate-varying motor system. The tongue during speech provides a motor system that can address this gap. In controlled speech experiments, using phrases containing complex tongue-movement sequences, we demonstrate distinct gaits in tongue movement at different speech rates. As spea...
Jarosinski SK, Sampson SN, Russell L.Injection of the centrodistal (CD) joint in the horse is a commonly performed procedure for both diagnostic and therapeutic purposes. This procedure can be technically challenging, and while radiographic guidance has been previously used, ultrasound localised injection of the CD joint has not been described. Objective: The purpose of this study was to explore the feasibility of using ultrasound localisation to increase the accuracy of CD joint injection. Methods: Experimental method assessment. Methods: One operator performed the ultrasound and injection of 24 CD joints in 12 sedated horses. T...
Backman T, Bruemmer JE, Graham JK, Squires EL.The ability to ship cooled stallion sperm for subsequent freezing at a facility specializing in cryopreservation would be beneficial to the equine industry. Stallion sperm has been centrifuged, cooled to 5 degrees C for 12 h, and frozen without a detrimental effect on motility in a previous study; however, no fertility data were available. Experiment 1 compared the post-thaw motility of sperm cooled for 18 h at 15 or 5 degrees C at either 400 or 200 x 10(6) sperm/mL and then frozen. Storage temperature, sperm concentration, or the interaction of temperature and concentration had no effect on t...
Hunter BG, Duesterdieck-Zellmer KF, Larson MK.Anecdotal accounts of tiludronate administration via intravenous regional limb perfusion (IVRLP) exist despite a lack of information regarding safety for synovial structures in the perfused area. The objective of this study was to determine whether tiludronate concentrations in synovial structures after IVRLP with low dose (0.5 mg, LDT) or high dose (50 mg, HDT) tiludronate remain below a value demonstrated in vitro to be safe for articular cartilage (<19,000 ng/ml), and to determine effects of tiludronate on synovial fluid cytology variables compared to saline perfused control limbs. Using...
Kaashoek M, Hobbs SJ, Clayton HM, Aerts P, Nauwelaerts S.To reduce anatomically unrealistic limb postures in a virtual musculoskeletal model of a horse's forelimb, accurate knowledge on forelimb joint constraints is essential. The aim of this cadaver study is to report all orientation and position changes of the finite helical axes (FHA) as a function of joint angle for different equine forelimb joints. Five horse cadaver forelimbs with standardized cuts at the midlevel of each segment were used. Bone pins with reflective marker triads were drilled into the forelimb bones. Unless joint angles were anatomically coupled, each joint was manually moved ...
Truax RE, Powell MD, Montelaro RC, Issel CJ, Newman MJ.A rapid and simple technique for the cryopreservation and recovery of equine mononuclear cells was developed. Buffy-coat leukocytes were frozen in autologous plasma containing 10% DMSO and mononuclear cells were recovered by gradient sedimentation using a standard Ficoll-Hypaque purification procedure. The total numbers of mononuclear cells recovered from cryopreserved samples were 94%-82% of those recovered from fresh blood samples. The functional capabilities of the mononuclear cells from cryopreserved buffy coat preparations were compared with those of mononuclear cells from fresh samples b...
Collier MA, Kallfelz FA, Rendano VT, Krook LP, Schryver HF.The use of capacitively coupled low-voltage signals for stimulation of osteogenesis has been reported in a variety of animal models. Electrically induced osteogenesis was investigated with a capacitively coupled electric field on a radius (distal-lateral orientation) osteotomy model, in conjunction with internal fixation and postoperative loading. Twelve adult horses of either sex were allotted to 2 groups of 6; 1 group was given electrical stimulation and the other served as controls. A low-voltage high-frequency capacitively coupled electrical signal was locally and continuously applied to t...
Thompson KN, Baker JP, Jackson SG.Thirty foals of mixed breeding, from two consecutive years, were used in two 120-d experiments to evaluate the effects of supplemental feeding (creep feed) on growth in nursing foals. At 10 d postpartum, foals were randomly assigned either to a creep-fed group (CF) or an unsupplemented group (NCF). Initial measurements of body weight (BW), height at the withers (WH), third metatarsal length (MtIII) and third metacarpal length (McIII) were made at 10 d of age and at 30-d intervals thereafter. Medial and lateral cortical peak values for radiographic bone density, cortical width and cortical area...
Brugmans F, Deegen E.To determine the efficacy of laparoscopic surgical techniques for repair of rectal lacerations in horses. Methods: Experimental study. Methods: Thirty-two segments of equine bowel placed in an equine pelvitrainer, 8 equine cadavers, and 3 normal horses. Methods: In experiment 1, 3 laparoscopic intestinal-repair techniques were evaluated in an equine pelvitrainer: suturing with needle holders, with an automatic suture device, and stapling with a hernia stapler. In experiment 2, descending colon lacerations were sutured laparoscopically using needle holders in a pelvitrainer and in equine cadave...
