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.
Kaese S, Frommeyer G, Verheule S, van Loon G, Gehrmann J, Breithardt G, Eckardt L.The most frequently used animal species in experimental cardiac electrophysiology are mice, rabbits, and dogs. Murine and human electrocardiograms (ECGs) show salient differences, including the occurrence of a pronounced J-wave and a less distinctive T-wave in the murine ECG. Mouse models can resemble human cardiac arrhythmias, although mice differ from human in cardiac electrophysiology. Thus, arrhythmia mechanisms in mice may differ from those in humans and should be transferred to the human situation with caution. Further relevant cardiovascular animal models are rabbits, dogs, and minipigs...
Kutzner-Mulligan J, Eisemann J, Siciliano P, Smith J, Hewitt K, Sharlette J, Pratt-Phillips S.Management techniques that reduce the insulin response to feeding in horses have application in preventing insulin resistance (IR) and potential associations (e.g., laminitis). Eight mature idle horses of BCS between 5 and 6.5 and with no previous indication of IR were fed a meal of concentrate under 4 feed delivery treatments in a repeated Latin Square design. Treatments were all based on a bucket of equal dimensions. The treatments included a control (CON) and 3 treatments hypothesized to increase time to consume feed (TCF): mobile obstacles above the feed (BALL), stationary obstacles below ...
Wagnerová P, Sak B, Květoňová D, Maršálek M, Langrová I, Kváč M.A total of 9 (8 stallions and 1 mare) 1 year old ponies were used for the experimental infection caused by Encephalitozoon cuniculi genotype II (10(7) spores per animal). Subsequently, individual horses were slaughtered 7, 14, 21, 28, 35, 42, 49, 56, and 63 days post infection. Immediately after slaughter, tissues samples of stomach, duodenum, jejunum, ileum, caecum, colon, spleen, liver, kidney, bladder, heart, lungs, and brain were sampled. In addition, urine, feces and blood specimens were collected. Enzyme-linked immunosorbent assay was used for determination of humoral immune response and...
Seo JP, Tsuzuki N, Haneda S, Yamada K, Furuoka H, Tabata Y, Sasaki N.Mesenchymal stem cells (MSCs) are promising candidates for cell-based therapy and tissue engineering approaches. Fetal bovine serum (FBS) is commonly used for in vitro MSC expansion; however, the use of FBS may be associated with ethical, scientific, and safety issues. This study aimed to compare the ability of allogeneic platelet lysate (PL) and FBS to cause equine bone marrow-derived MSC expansion. MSCs were isolated from bone marrow aspirate in media supplemented with either PL or FBS, and cell proliferation properties and characteristics were examined. There were no significant differences...
Makra Z, Tuboly T, Bodó G.The aim of this study was to describe long-term follow-up and difference in immune reactions in the tear film following penetrating keratoplasty (PK) in horses when differently preserved corneas were utilised. This report describes for the first time the use of corneal grafts preserved in tissue culture media in equine PK. Eight experimental horses with normal eyes were included and freshly harvested, frozen or preserved corneal grafts were used for the PK. The graft-taking technique and storage, PK surgery, postoperative treatments and complications are described. The mean postoperative follo...
Paillot R, Prowse L, Montesso F, Stewart B, Jordon L, Newton JR, Gilkerson JR.Equine influenza (EI) is a major respiratory disease of horses. Recent outbreaks of EI have demonstrated the ease with which EI virus (EIV) can be transmitted internationally. This study aimed to improve our understanding of EIV shedding after infection of vaccinated horses, which would inform possible changes to current quarantine requirements. Our objectives were to compare commonly used diagnostic tests and to evaluate the relative merits of nasal and nasopharyngeal swabs for detection of EIV in vaccinated and unvaccinated ponies following EIV infection and to use these data to inform optim...
MacKay RJ, Wyer S, Gilmour A, Kongara K, Harding DR, Clark S, Mayhew IG, Thomson CE.Pasture-associated stringhalt is an acquired equine disease characterized by peripheral neuropathy and hyperflexion of the pelvic limbs. The disease occurs most commonly during periods of drought in horses grazing pastures heavily contaminated by Hypochaeris radicata. We hypothesized that stringhalt is caused by neurotoxins elaborated by H. radicata in response to the stress of drought conditions. Supernates were collected from H. radicata that were stressed (or not) by immersion in copper chloride solution, then extracted with ethyl acetate and dried. Dilutions of extracts from stressed (SE) ...
Textor JA, Tablin F.(1) To report the clinical and synovial effects of a platelet-rich product (PRPr) in normal equine joints, (2) to assess the persistence of platelets within synovial fluid after intra-articular injection, (3) to compare responses to different preparations of that product, and (4) to evaluate a gravity filtration system for PRPr preparation in horses. Methods: Experimental. Methods: A platelet-rich saline product (PRPr) was prepared from 7 normal horses using a proprietary preparation device and was divided into 3 treatments: resting, CaCl2 -activated (23 mM, final), and bovine thrombin-activ...
Rendle DI, Rutledge F, Hughes KJ, Heller J, Durham AE.Metformin is a potential therapeutic agent for the treatment of insulin resistance (IR). In laboratory animals, orally administered metformin reduces intestinal glucose absorption and may therefore affect insulinaemic responses to oral carbohydrate ingestion. Objective: To determine whether pretreatment with metformin reduces plasma glucose concentration and insulin responses following consumption of dextrose in horses. Methods: Therapeutic cross-over study. Methods: Seven healthy Standardbred and Thoroughbred geldings were subjected to an oral dextrose challenge test on 4 occasions: with and ...
Morató R, Soares JM, Orero G, Mogas T, Miró J.The effect of combining double layer density gradient centrifugation (DL-DGC) with different capacitation treatments on the fertilising capacity of frozen-thawed stallion sperm was examined via a heterologous assay involving in vitro-matured, zona pellucida-free bovine oocytes. In a first experiment, aliquots of frozen-thawed stallion sperm were subjected to one of five capacitation treatments without DL-DGC - ionomycin at 1.0μM, 0.1μM, 0.05μM or 0.01μM, or caffeine at 200μg/mL. The fertilising capacity of the semen was then assessed at 18h by staining the above oocytes with 4,6-diamidino...
Sole A, Spriet M, Padgett KA, Vaughan B, Galuppo LD, Borjesson DL, Wisner ER, Vidal MA.Intralesional (i.l.) injection is currently the most commonly used technique for stem cell therapy in equine tendon injury. A comparison of different techniques of injection of mesenchymal stem cells for the treatment of tendon lesions is required. Objective: We hypothesised that vascular perfusion of the equine distal limb with mesenchymal stem cells (MSCs) would result in preferential distribution of MSCs to acute tendon injuries. Methods: In vivo experimental study. Methods: Lesions were surgically induced in forelimb superficial digital flexor tendons of 8 horses. Three or 10 days after le...
Lester GD, Merritt AM, Kuck HV, Burrow JA.Intravenous (IV) and intragastric (IG) administration of fluid therapy are commonly used in equine practice, but there are limited data on the systemic, renal, and enteric effects. Objective: IV fluid administration will increase intestinal and fecal hydration in a rate-dependent manner after hypertonic dehydration, but will be associated with significant urinary water and electrolyte loss. Equivalent volumes of IG plain water will result in comparatively greater intestinal hydration with less renal loss. Methods: Six Thoroughbred geldings. Methods: Experimental study. 6 by 6 Latin square desi...
Nieto JE, Morales B, Yamout SZ, Stanley SD, Harmon FA, Snyder JR.To determine the response to neostigmine of the contractile activity of the jejunum and pelvic flexure and the effects of a continuous rate infusion (CRI) of neostigmine in horses. Methods: 7 adult horses and tissue from 12 adult horses. Methods: A CRI of neostigmine (0.008 mg/kg/h) or placebo was administered to 6 horses in a crossover study design. Gastric emptying was evaluated by the acetaminophen test. The frequency of defecation and urination and the consistency and weight of feces were recorded throughout the experiment. The effect of neostigmine on smooth muscle contractile activity wa...
Vairo S, Van den Broeck W, Favoreel H, Scagliarini A, Nauwynck H.The upper respiratory tract mucosa represents the first line of defense, which has to be overcome by pathogens before invading the host. Considering the economic and ethical aspects involved in using experimental animals for pathogenesis studies, respiratory mucosal explants, in which the tissue's three-dimensional architecture is preserved, may be ideal alternatives. Different respiratory mucosal explant cultures have been developed. However, none of them could be inoculated with pathogens solely at the epithelium side. In the present study, equine nasal and nasopharyngeal explants were embed...
Lange-Consiglio A, Corradetti B, Meucci A, Perego R, Bizzaro D, Cremonesi F.This is the first study comparing stemness features of equine mesenchymal progenitor cells derived from amniotic membrane and bone marrow. Objective: To investigate an alternative and noninvasive stromal cell source for equine tissue engineering. Methods: In vitro experimental study of the characteristics of equine mesenchymal progenitor cells derived from amnion and bone marrow. Methods: Cells isolated from amniotic membrane and bone marrow were analysed for proliferation (growth curve, doubling time, colony forming unit). Immunocytochemical detection of pluripotency markers and gene expressi...
Chandriani S, Skewes-Cox P, Zhong W, Ganem DE, Divers TJ, Van Blaricum AJ, Tennant BC, Kistler AL.Theiler's disease is an acute hepatitis in horses that is associated with the administration of equine blood products; its etiologic agent has remained unknown for nearly a century. Here, we used massively parallel sequencing to explore samples from a recent Theiler's disease outbreak. Metatranscriptomic analysis of the short sequence reads identified a 10.5-kb sequence from a previously undescribed virus of the Flaviviridae family, which we designate "Theiler's disease-associated virus" (TDAV). Phylogenetic analysis clusters TDAV with GB viruses of the recently proposed Pegivirus genus, altho...
Lucia JL, Coverdale JA, Arnold CE, Winsco KN.Nineteen weanling Quarter Horses (225 to 380 kg) were used in a randomized complete block design to investigate the effects of intra-articular lipopolysaccharide (LPS) to induce acute joint inflammation in young horses. Horses were blocked by age, BW, and sex and were randomly assigned to 1 of 3 treatments for a 35-d experiment. Treatments included intra-articular injection of 0.25 ng (n = 7) or 0.50 ng (n = 6) of LPS obtained from Escherichia coli O55:B5 or sterile lactated Ringer's solution (n = 6; control) into the radial carpal joint. Synovial fluid was obtained at preinjection h 0 and 2, ...
Raabe O, Shell K, Goessl A, Crispens C, Delhasse Y, Eva A, Scheiner-Bobis G, Wenisch S, Arnhold S.Mesenchymal stem cells are regarded as common cellular precursors of the musculoskeletal tissue and are responsible for tissue regeneration in the course of musculoskeletal disorders. In equine veterinary medicine extracorporeal shock wave therapy (ESWT) is used to optimize healing processes of bone, tendon and cartilage. Nevertheless, little is known about the effects of the shock waves on cells and tissues. Thus, the aim of this study was to investigate the influence of focused ESWT on the viability, proliferation, and differentiation capacity of adipose tissue-derived mesenchymal stem cells...
Moro FL, Spröwitz A, Tuleu A, Vespignani M, Tsagarakis NG, Ijspeert AJ, Caldwell DG.This manuscript proposes a method to directly transfer the features of horse walking, trotting, and galloping to a quadruped robot, with the aim of creating a much more natural (horse-like) locomotion profile. A principal component analysis on horse joint trajectories shows that walk, trot, and gallop can be described by a set of four kinematic Motion Primitives (kMPs). These kMPs are used to generate valid, stable gaits that are tested on a compliant quadruped robot. Tests on the effects of gait frequency scaling as follows: results indicate a speed optimal walking frequency around 3.4 Hz, an...
Noble GK, Sillence MN.As growth hormone increases lean body mass, it could be a therapy for obese horses. However, growth hormone use induces hyperinsulinaemia in some species, so further investigation is warranted. Objective: To investigate the effects of feeding, exercise and growth hormone therapy on basal insulin concentrations in healthy horses. Methods: In vivo experimental study. Methods: Blood samples were obtained every 30 min from 12 geldings over 24 h, to establish basal serum insulin concentrations, before they underwent a 3-week exercise programme. Horses were allocated into 2 groups and exercised for ...
Bohannon LK, Owens SD, Walker NJ, Carrade DD, Galuppo LD, Borjesson DL.Joint inflammation and septic arthritis are both potential complications of intra-articular injections of bone marrow-derived mesenchymal stem cells (BM-MSCs). Clinicians may prophylactically co-inject BM-MSCs admixed with either antimicrobials or hyaluronic acid; however, the effect of these agents on cultured BM-MSCs is unknown. Objective: To determine the effects of therapeutic levels of gentamicin, amikacin and hyaluronic acid on cultured equine BM-MSCs in vitro. Methods: In vitro experimental study. Methods: Equine BM-MSCs from 4 healthy mature horses were isolated. Cultured BM-MSCs from ...
Ahern BJ, Showalter BL, Elliott DM, Richardson DW, Getman LM.To compare the in vitro biomechanical properties of a 4.5 mm narrow locking compression plate (PIP-LCP) with 2 abaxially located transarticular screws and a 4.5 mm limited contact dynamic compression plate (LC-DCP) with 2 abaxially located transarticular screws using equine pasterns. Methods: Experimental. Paired in vitro biomechanical testing of 2 methods for stabilizing adult equine forelimb PIP joints. Methods: Adult equine forelimbs (n = 8 pairs). Methods: Each pair of PIP joints were randomly instrumented with either a PIP-LCP or LC-DCP plate axially and 2 parasagitally positioned 5.5 mm ...
Bischofberger AS, Hadidane I, Wereszka MM, Perkins NR, Jeffcott LB, Dart AJ.To determine the effect of horse age and laryngeal prosthesis location on rima glottidis area in cadaveric larynges. Methods: Experimental study. Methods: Cadaveric equine larynges (n = 40). Methods: Specimens were grouped by age: group 1, ≤5 years (n = 18); group 2, >5 to ≤10 years (n = 12); group 3, >10 years (n = 10). A cranial prosthesis was placed through the dorsal cricoid spine at 70% of the distance of the total cricoid length measured from the caudal rim. A dorsal prosthesis was placed through the caudal rim of the cricoid on the dorsal midline. A lateral prosthesis was plac...
Anderson SL, Bracamonte JL, Hendrick S, Carmalt JL, Wilson DG.To compare bursting strength and failure mode between ventral median celiotomies closed with USP 7 braided polydioxanone (7PD) or USP 2 polyglactin 910 (2PG). Methods: Ex vivo experimental. Methods: Equine cadavers (n = 10). Methods: A 25 cm ventral median 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 2 sections of 7PD or 2PG. The bladder was inflated with compressed air until construct failure. The horses' signalment, body weight, suture type, failure mode (suture or abdom...
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...
Olstad K, Hendrickson EH, Carlson CS, Ekman S, Dolvik NI.To transect blood vessels within epiphyseal cartilage canals and observe whether this resulted in ischaemic chondronecrosis, an associated focal delay in enchondral ossification [osteochondrosis (OC)] and pathological cartilage fracture [osteochondrosis dissecans (OCD)] in the distal femur of foals, with potential translational value to the pathogenesis of juvenile osteochondritis dissecans (JOCD) in children. Methods: Ten Norwegian Fjord Pony foals were operated at the age of 13-15 days. Two vessels supplying the epiphyseal growth cartilage of the lateral trochlear ridge of the left distal fe...
Lavin TE, Nielsen BD, Zingsheim JN, O'Connor-Robison CI, Link JE, Hill GM, Shelton J.An experiment was conducted to study P digestibility in mature horses because of the growing environmental concerns regarding P runoff and previous equine research focused mostly on young and growing animals or used ponies as a model. Phytase supplementation of swine and poultry diets can result in greater phytate-P digestibility, leading to a decreased need for inorganic P supplementation and a decrease in P excreted to the environment; this, however, has not been demonstrated in the horse. Six mature Arabian geldings were fed 6 diets consisting of pelleted concentrate and alfalfa hay. The co...
Deniau V, Depecker M, Bizon-Mercier C, Couroucé-Malblanc A.To compare the changes in splenic length and thickness and in packed cell volume (PCV) following detomidine or xylazine administration and subsequent epinephrine infusion. Objective: Spleen relaxation occurs following xylazine or detomidine administration and interferes with subsequent splenic contractile response to epinephrine. Methods: Randomized non-blinded crossover experimental study. Methods: 6 healthy adult mares. Methods: The mares received an intravenous (IV) epinephrine infusion (1 μg kg(-1 ) minute(-1) over 5 minutes) one hour after IV administration of detomidine (0.01 mg kg(-1) ...
Fortier G, Richard E, Hue E, Fortier C, Pronost S, Pottier D, Lemaitre L, Lekeux P, Borchers K, Thiry E.The aim of this trial was to investigate the putative involvement of equid herpesvirus 2 (EHV-2) in airway inflammation of adult horses. Six horses received corticosteroid treatment, before either mock infection (n=2) or EHV-2 strain LK4 inoculation (n=4). These four horses were also submitted to immunosuppression 84 days post inoculation. EHV-2 was detected by quantitative PCR in respiratory samples up to respectively 21 days and 14 days. Nested PCR, cloning and sequencing allowed the detection of five different 'field' strains throughout the trial. Neutrophils proportions were transiently in...
Munsterman AS, Dias Moreira AS, Marqués FJ.Wei Le San (WLS) is a Chinese herbal formula comprised of 9 herbs selected for their putative anti-inflammatory effects. Objective: To evaluate the effects of WLS administration in horses with nonglandular gastric ulcers. Methods: Ten mixed breed mares (aged 7-21 years, 401-567 kg body weight). Methods: Experimental design was a blinded, prospective, 2-period crossover study. All horses received a placebo (25 mL dextrose-based syrup; n = 10) and the treatment (WLS, 5 g in 25 mL dextrose-based syrup; n = 10), administered twice daily. Horses underwent a 1-week, alternating feed-depriv...
Vercruysse J, Eysker M, Demeulenaere D, Smets K, Dorny P.A controlled trial was carried out to evaluate the persistence of the effect against small strongyles of a 2 per cent moxidectin gel administered orally to foals at a dose rate of 0.4 mg/kg bodyweight. Five of nine helminth-free foals were treated on day 0, and the remaining four foals were used as controls. On days 0, 7, 14, 21 and 28 all nine foals were infected experimentally with 200,000 small strongyle larvae. Three treated and two control foals were necropsied on day 42 and the rest on day 43. Fourteen species of small or medium sized small strongyles were found in the control foals, 10 ...
Regenerative medicine applied to skin lesions is a field in constant improvement. The use of biomaterials with integrin agonists could promote cell adhesion increasing tissue repair processes. The aim of this pilot study was to analyze the effect of an α4β1 integrin agonist on cell adhesion of equine adipose tissue (AT) and Wharton's jelly (WJ) derived MSCs and to investigate their adhesion ability to GM18 incorporated poly L-lactic acid (PLLA) scaffolds. Adhesion assays were performed after culturing AT- and WJ-MSCs with GM18 coating or soluble GM18. Cell adhesion on GM18 containing PLLA sc...
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...
Holcombe SJ, Rodriguez K, Lane J, Caron JP.To determine (1) if the cricothyroid muscle had respiratory-related electromyographic (EMG) activity that increased with respiratory effort and (2) if bilateral cricothyroid myotomy resulted in vocal fold instability and collapse in exercising horses. Methods: Experimental. Methods: Seven (3 EMG; 4 cricothyroid myotomy) Standardbred horses. Methods: Three horses exercised on a treadmill at speeds corresponding to the speed that produced maximum heart rate (HR(max)), 75% of maximum heart rate (HR(75%max)), and 50% of maximum heart rate (HR(50%max)) for 60 seconds at each speed while EMG activit...
Plunkett AH, Schoonover MJ, Young JM, Taylor JD, Holbrook TC.To determine the influence of location and movement on subtourniquet pressure (STP) generated by application of a wide-rubber tourniquet (WRT) on equine limbs. Methods: Randomized experimental cross-over design. Methods: Six standing, sedated horses. Methods: Horses were sedated with detomidine hydrochloride (0.2 μg/kg IV), and 4 investigators applied WRTs to the antebrachium (AB), gaskin (GK), and midmetacarpus (MC) of each horse in a predetermined, randomized order. Subtourniquet pressure was consequently measured at 10-minute intervals (T0, T10, T20, T30) for 30 minutes. Indirect systo...
Edmond AJ, Brinsko SP, Love CC, Blanchard TL, Teague SR, Varner DD.Centrifugal fractionation of semen is commonly done to improve quality of human semen in assisted-reproduction laboratories, allowing sperm separation based on their isopycnic points. Sperm with morphologic abnormalities are often more buoyant, promoting their retention above defined density media, with structurally normal sperm passing through the media following centrifugation. Three experiments were conducted to evaluate the effects of density-medium type, centrifuge-tube size, sperm number, and density-medium volume (column height) on stallion sperm quality and recovery rate in sperm pelle...
Pearce SG, Hurtig MB, Boure LP, Radcliffe RM, Richardson DW.To investigate the feasibility of resurfacing the equine fetlock joint using cylindrical, orthotopic, press-fit, osteochondral allografts. Methods: Experimental study. Methods: Ten mature, mixed-breed horses. Methods: Cylindrical, osteochondral grafts (6.5-mm diameter) were harvested aseptically from cadaveric equine metatarsophalangeal joints. Allografts were transplanted into 6 horses; 4 horses were sham operated. The surgical approach involved creation of a bone block at the origin of the medial collateral ligament and luxation of the metatarsophalangeal joint. Grafts were placed into the m...
Ahern BJ, Boston RC, Parente EJ.Mechanical evaluation of a novel alternate laryngoplasty system (ALPS). Methods: Experimental. Methods: Cadaveric horse larynges (n = 10). Methods: Arytenoid and cricoid cartilages were embedded for testing. A novel laryngoplasty system consisting of a metallic anchor, 2 stands of #2 suture material, and a metallic button were evaluated. A traditional laryngoplasty using a single strand of #5 Ethibond was evaluated in parallel. Constructs were evaluated in cyclic testing oscillating from 30 to 50 N for 3600 cycles. Constructs subsequently underwent a single cycle to failure. Distraction during...
Ferreira TH, Allen M, De Gasperi D, Buhr KA, Morello SL.To assess the effects of two sizes of silicone endotracheal tubes with internal diameter 26 mm (ETT) and 30 mm (ETT) inflated to minimum occlusive volume on tracheal and laryngeal mucosa of adult horses anesthetized for 2 hours with isoflurane. Methods: Prospective, randomized, blinded, crossover experimental study. Methods: A total of eight healthy adult mares. Methods: Upper airway endoscopy and ultrasound measurements of internal tracheal diameter were performed the day before anesthesia. Horses were anesthetized and orotracheally intubated with ETT or ETT. Ease of intubation was scored. Th...
Medina-Torres CE, Underwood C, Pollitt CC, Castro-Olivera EM, Hodson MP, Richardson DW, van Eps AW.Lamellar perfusion is thought to be affected by weightbearing and limb load cycling; this may be critical in the development of supporting limb laminitis. Objective: To document the effects of unilateral weightbearing and altered limb load cycling on lamellar energy metabolism and perfusion. Methods: Randomised, controlled (within subject), experimental trial. Methods: Nine Standardbred horses were instrumented with microdialysis probes in the foot lamellar tissue and skin (over the tail base). Urea (20 mmol/l) was added to the perfusate. Samples were collected every 15 min for a 1 h con...
Vigani A, Shih A, Queiroz P, Pariaut R, Gabrielli A, Thuramalla N, Bandt C.New volumetric variables of preload, such as total end-diastolic volume index (TEDVI) and active circulation volume index (ACVI) and central blood volume index (CBVI), may represent good indicators of preload and predictors of fluid responsiveness. During acute changes of intravascular volume these variables would allow a more accurate intervention. Objective: The aim of the present study was to investigate the changes in TEDVI, ACVI, CBVI in a juvenile model of hemorrhagic shock and resuscitation. Methods: Twelve anaesthetized ponies (3-8 months of age) were studied at normovolaemia (BASE), a...
van Doorn DA, Schaafstra FJ, Wouterse H, Everts H, Estepa JC, Aguilera-Tejero E, Beynen AC.This study addresses the question of whether feeding rations rich in P for a period of up to 42 d induces a positive P balance in adult ponies. Biochemical bone markers and parathyroid hormone (PTH; intact as well as whole PTH) were measured to obtain clues as to the effect of P loading on bone metabolism. The experiment had a Latin square design. Each feeding period lasted 42 d, and there were 2 balance trials (ECP1 and ECP2) within each feeding period. Each balance trial lasted 10 d (ECP1: d 11 to 21; ECP2: d 33 to 42). Six ponies aged 2.5 to 7 yr were fed a control diet that provided P and ...
Wolker RR, Wilson DG, Allen AL, Carmalt JL.To determine whether intra-articular 70% ethyl alcohol alone (IAEA) or in combination with 2 percutaneously placed transarticular lag screws (EA-TLS) would result in arthrodesis of the equine proximal interphalangeal (PIP) joint. Methods: Experimental. Methods: Healthy horses (n=6), aged 1.5-3 years, free of lameness, diagonally paired front and hind PIP joints. Methods: Six milliliters 70% ethyl alcohol was injected into randomly selected diagonally paired front and hind PIP joints. Thirty days later, 2 parallel 5.5 mm cortical screws were inserted in lag fashion across the hind PIP joints an...
Schwarm A, Clauss M, Ortmann S, Jensen RB.Sieve analyses of hindgut contents of horses as well as observations in horses where plastic markers had been applied to a caecal cannula suggested that there may be a discrimination by particle size in the passage or retention of digesta. Here, we performed a similar experiment with five caecum-cannulated horses (562 ± 31 kg) fed a constant amount (6.81 kg dry matter/day) of grass hay. Passage markers representing the liquid (Co-EDTA) as well as the particulate digesta phase (Yb-undefined; Cr mordanted fibre 1-2 mm; Ce-mordanted fibre 8 mm) were given as a pulse-dose into the can...
Henselek Y, Fischer J, Schloegl C.The ability to understand the relation between quantities has been documented in a wide range of species. Such quantity discrimination competences are commonly demonstrated by a choice of the larger quantity or numerosity in a two-choice task. However, despite their overall success, many subjects commit a surprisingly large number of errors even in simple discriminations such as 1 vs. 3. Recently, it had been suggested that this is a result of the testing procedure. When monkeys could choose between different quantities of edible rewards, they showed low-level success. If, however, they chose ...
Lima-Neto JF, Fernandes CB, Alvarenga MA, Golim MA, Landim-Alvarenga FC.This experiment aimed to study equine fibroblasts in culture analyzing and the cell cycle and viability of cells pre- and post-freezing. Skin fragments were obtained from 6 horses and cultured in DMEM high glucose + 10% FCS in 5% CO(2) until the beginning of confluence. Two passages were performed before freezing. Cells subjected to serum starvation (0.5% FCS) were analyzed for viability and cell cycle at 24, 48, 72, 96, 120, 144 and 168 h of culture. For the confluent groups, cells were analyzed at the moment they achieved confluence. Cellular viability was assisted with Hoescht 33342 and pro...
Yvorchuk-St Jean K, Gaughan E, St Jean G, Frank R.To evaluate the effect of a porous bovine-derived collagen membrane (PBCM) on the rates of wound healing, cellular events, presence of granulation tissue, and appearance at termination of the study in surgically created full-thickness cutaneous wounds of the distal portion of the extremities of horses. Methods: Treated wounds (n = 12) received a PBCM dressing and control wounds were covered with a nonadherent dressing. Forelimbs and hind limbs were cross paired; the right forelimb and left hind limb always received the same dressing application, as did the left forelimb and right hind limb. Li...
Peltier MR, Robinson G, Sharp DC.The effects of melatonin implant treatment over a 4 wk period at the summer solstice on the transition into and out of the following anovulatory season were evaluated in ovary-intact and ovariectomized mares. Melatonin implants tended to delay the timing of the final ovulation of the breeding season (P = 0.0797) in the ovary-intact mares. Although the decline in LH secretion associated with the end of the breeding season was parallel between treatments and ovarian statuses, the rate of LH secretion, as expressed by its mathematical accumulation, was lower in ovariectomized, melatonin-treated m...
Clay CM, Squires EL, Amann RP, Nett TM.Influence of day length on seasonal endocrine responses were studied using stallions (seven per group). Treatments included 1) control, with natural day length; 2) 8 h light and 16 h dark (8:16) for 20 wk beginning July 16, 1982 then 16:8 from December 2, 1982 until March 5, 1984 (S-L); or 3) 8:16 from July 16, 1982 until March 5, 1984 (S-S). Blood was sampled hourly for 5 h every 4 wk; sera were pooled within horse, and luteinizing hormone (LH), follicle-stimulating hormone (FSH) and testosterone were quantified. Blood was collected every 20 min for 24 h every 8 wk and 2 wk before and after t...
Torbeck RL, Prieur DJ.Cartilaginous defects were created in the radiocarpal joints of 12 horses. Synovial fluid cytologic features, lysozyme activity, and beta-glucuronidase activity were monitored for 16 days. A comparison was made of plasma lysozyme and beta-glucuronidase activity and of synovial fluid lysozyme, beta-glucuronidase, and leukocyte concentrations. Plasma lysozyme was found to be independent of synovial fluid lysozyme activity. Synovial fluid lysozyme was significantly increased (P less than 0.001) in all joints with surgically induced defects (group I) compared with controls (arthrocentesis done; gr...
Saleh AG, El-Habashi N, Abd-Ellatieff HA, Abas OM, Anwar S, Fukushi H, Yanai T.Equine herpesvirus-9 (EHV-9), equine herpesvirus-1 (EHV-1) and zebra-borne EHV-1 are members of the family Herpesviridae and cause encephalitis and rhinopneumonitis in a range of animal species. The aim of this study was to characterize and compare the rhinopneumonitis induced by experimental intranasal inoculation of groups of hamsters with EHV-9, EHV-1 strain Ab4p or zebra-borne EHV-1 viruses. Animals inoculated with EHV-9 had earlier and more severe neurological and respiratory signs than those inoculated with EHV-1 strain Ab4p or zebra-borne EHV-1. At 4-5 days post inoculation (dpi), hamst...
Hunt RJ, Allen D, Moore JN.Using a pump-perfused extracorporeal isolated digital preparation, the effects of a 30-minute infusion of either saline solution (control) or endotoxin on equine digital hemodynamics and microvascular function were determined. Digital blood flow and arterial, venous, and capillary pressures were recorded at 15-minute intervals for 150 minutes. From these data, total vascular resistance and pre- and postcapillary resistances were calculated. Isogravimetric capillary filtration coefficient, vascular compliance, and the osmotic reflection coefficient were determined after the last hemodynamic mea...
Choi YH, Velez IC, Macías-García B, Hinrichs K.In nuclear transfer (NT), exposure of donor cell chromatin to the ooplast cytoplasm may aid reprogramming; however, the length of exposure feasible is limited by the developmental life span of the oocyte. We examined the effect of duration of nucleus-cytoplasmic exposure before activation and of in vitro maturation (IVM) in equine NT. In experiment 1, 24 h IVM and a delay of 2, 5, or 8 h between reconstruction and activation yielded 4%, 15%, and 11% blastocysts, respectively. In experiment 2, a 5-h activation delay yielded 17% and 22% blastocysts with two donor cell lines. In experiment 3, usi...
Stewart AS, Schaaf CR, Veerasammy B, Freund JM, Gonzalez LM.Equine intestinal epithelial stem cells (ISCs) serve as potential targets to treat horses with severe intestinal injury. The ability to isolate and store ISCs from intestinal biopsies creates an opportunity for both in vitro experiments to study ISC dynamics in a variety of intestinal diseases, and, in the future, utilize these cells as a possible therapy. If biopsies could be successfully stored prior to processing for ISCs, this would increase the availability of sample repositories for future experimental and therapeutic use. However, delayed culture of equine ISCs following prolonged sampl...
Todhunter RJ, Minor RR, Wootton JA, Krook L, Burton-Wurster N, Lust G.Our aim was to determine if mild to moderate postoperative exercise and intra-articular polysulfated glycosaminoglycan result in improved repair of large, experimentally induced osteochondral defects in a weight-bearing surface of equine joints. Arthroscopic debridement was used to produce full-thickness defects in a weight-bearing area of the radial carpal bones in 18 ponies. The ponies were randomly assigned to two groups balanced for age: nine animals in the exercise and nine in the no exercise group. Six ponies in each group were medicated weekly for 5 weeks with an intra-articular injecti...
Hardy J, Bertone AL, Weisbrode SE, Muir WW, O'Dorisio TM, Masty J.To describe the acute cellular response, inflammatory mediator release, and effect on chondrocyte metabolism of interleukin 1 beta (IL-1 beta) in isolated innervated or denervated equine metacarpophalangeal joints. Methods: One metacarpophalangeal joint of 24 adult horses. Methods: The metacarpophalangeal joint was isolated for 6 hours in a pump-perfused, auto-oxygenated, innervated or denervated metacarpophalangeal joint preparation. Isolated joints were assigned to 4 groups: control, control-denervated, inflamed, and inflamed-denervated, and inflammation was induced by intra-articular inject...
Ragle CA, Meagher DM, Schrader JL, Honnas CM.A blind study was designed to determine if abdominal auscultation is an effective method for detecting the presence of intestinal sand. Fifteen horses divided into two groups were used in the study. There were seven horses in Group 1 and eight horses in Group 2. All horses were auscultated and determined to be free of sand sounds before initiation of Trial 1. Group 1 horses were given 4.2 g/kg body weight of sand via nasogastric tube using carboxymethylcellulose (CMC) as a suspending agent at 9.0 ml/kg body weight. Group 2 horses were given CMC only. Horses remained in the same group through a...
Trahan RA, Byron CR, Dahlgren LA, Pleasant RS, Werre SR.OBJECTIVE To compare the effects of 3 equimolar concentrations of methylprednisolone acetate (MPA), triamcinolone acetonide (TA), and isoflupredone acetate (IPA) on equine articular tissue cocultures in an inflammatory environment. SAMPLE Synovial and osteochondral explants from the femoropatellar joints of 6 equine cadavers (age, 2 to 11 years) without evidence of musculoskeletal disease. PROCEDURES From each cadaver, synovial and osteochondral explants were harvested from 1 femoropatellar joint to create cocultures. Cocultures were incubated for 96 hours with (positive control) or without (n...
Kinsley R, Pronost S, De Bock M, Temperton N, Daly JM, Paillot R, Scott S.Equine influenza is a major respiratory disease of horses that is largely controlled by vaccination in some equine populations. Virus-neutralising antibodies, the mainstay of the protective immune response, are problematic in assaying for equine influenza virus, as most strains do not replicate efficiently in cell culture. Surrogate measures of protective antibody responses include the haemagglutination inhibition (HI) test and single radial haemolysis (SRH) assay. For this study, a pseudotyped virus, bearing an envelope containing the haemagglutinin (HA) from the Florida clade 2 equine influe...
