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.
Aguilera-Tejéro E, Pascoe JR, Woliner MJ.Effects of phenylbutazone (PBZ) and furosemide (FUR) on the respiratory tract of horses were evaluated, focusing on bronchial responsiveness. Four healthy Thoroughbreds were used and data were analyzed by use of a Latin square design. Histamine provocation tests (0.5, 1, 2, and 4 micrograms/min, i.v.) were done: (1) without prior treatment with PBZ or FUR, (2) 30 minutes after administration of PBZ (8 mg/kg, i.v.), (3) 1 hour after administration of FUR (1 mg/kg, i.v.), and (4) after administration of PBZ plus FUR. Pulmonary function tests (dynamic compliance, resistance, respiratory frequency...
Thein P, Darai G, Janssen W, Bergle RD, Strube W, Floss G.From spring 1990 to summer 1991 we investigated 21 horses with clinical symptoms of EHV-infection by means of serological and virological methods including DNA-hybridization to identify the causative agents. The results indicated that, as already reported by us, EHV4 may also cause the paralytic form of the infection. The possibility of double infection with EHV4 and EHV1 cannot be excluded. In 3 out of 21 affected horses we could investigate brain tissue and/or spinal fluid by Dotblot hybridization with EHV1 and EHV4-DNA. The investigated samples of all three horses showed hybridization with ...
Denac M, Bebié P, Scharrer E.The effects of various neurotransmitters and electrical field stimulation on muscle strips from the distal equine esophagus were studied. Acetylcholine (ACH) caused concentration dependent (1.1-55 x 10(-6) mol/l) contractions of the longitudinal and circular muscle strips from the distal esophagus as well as from the lower esophageal sphincter (LES). Atropine (10(-5) mol/l) blocked these contractions. Noradrenaline (NA) induced concentration related (1.1-55 x 10(-6) mol/l) contractions of the muscle strips from the LES. This excitatory effect of noradrenaline was antagonized by the alpha 1-rec...
Blikslager AT, Tate LP, Weinstock D.Effects of neodymium:yttrium aluminum garnet (Nd:YAG) laser irradiation on equine endometrium were evaluated in vitro and in six mares with endometrial cysts. The Nd:YAG laser was applied to six endometrial sites, in each of five uterine specimens, with power densities of 5659 to 33,954 J/cm2. Depth of tissue ablation was measured and graded on histologic sections of the tissue lesions. Power density had a significant effect on the depth of tissue ablation (p < .001). Grade 3 lesions (full-thickness ablation of the endometrium) were created with energy densities of 16,977 to 33,954 J/cm2. Six ...
Sullivan KE, Snyder JR, Madigan JE, Pascoe JR, Farver TB, Thurmond MC, Andresen JW.Granulocyte colony-stimulating factor (G-CSF) is a glycoprotein that regulates the proliferation and maturation of hematopoietic progenitor cells and modulates the function of mature neutrophils. The responses to administration of G-CSF alone, and in combination with antimicrobials, were studied in an equine model of ascending colon ischemia. Complete segmental colonic ischemia (3.75 hours) with pelvic flexure enterotomy was created in four treatment groups. Group 1 horses received recombinant canine G-CSF (10 micrograms/kg, every 24 hours, intramuscularly), gentamicin sulfate (2.2 mg/kg, ever...
Allen GK, Green EM, Robinson JA, Garner HE, Loch WE, Walsh DM.We examined the effect of infusion of lipopolysaccharide (LPS) on serum tumor necrosis factor alpha (TNF alpha) concentration and clinical attitude in 2- 3-day-old colostrum-fed (CF) and colostrum-deprived (CD) foals. Eleven CF and 8 CD neonatal foals were given a bolus i.v. infusion of Escherichia coli O55:B5 lipopolysaccharide (0.5 microgram/kg of body weight) in sterile saline (0.9% NaCl) solution. Four CF and 2 CD foals were given saline solution alone. Serum IgG concentration and serum anti-LPS IgG(T) antibody titer were determined for each foal prior to infusion. A depression index was u...
Canè V, Botti P, Soana S.The influence of pulsed low-frequency electromagnetic fields (PEMFs) on bone formation was investigated in studies of the healing process of transcortical holes, bored at the diaphyseal region of metacarpal bones of six adult horses, exposed for 30 days to PEMFs (28 G peak amplitude, 1.3 ms rise time, and 75 Hz repetition rate). A pair of Helmholtz coils, continuously powered by a pulse generator, was applied for 30 days to the left metacarpal bone, through which two holes, of equal diameter and depth, had been bored at the diaphyseal region. Two equal holes, bored at the same level in the rig...
Robinson JA, Allen GK, Green EM, Garner HE, Loch WE, Walsh DM.Serum interleukin-6 (IL-6) concentration was measured in 11 colostrum-fed (CF) and 8 colostrum-deprived (CD) 2- to 3-day-old foals after foals were infused with lipopolysaccharide (LPS; Escherichia coli O55:B5 endotoxin, 0.5 microgram/kg of body weight in sterile saline [0.9% NaCl] solution). Four CF and 2 CD foals were given saline solution alone. Serum IL-6 concentration was estimated by use of an in vitro proliferative bioassay, using the IL-6 dependent B.13.29 clone 9 cells. Interleukin-6 concentration increased in all LPS-infused foals, and geometric mean serum IL-6 concentration was sign...
Lepage OM, Laverty S, Marcoux M, Dumas G.The effect of triamcinolone acetonide (0.09 mg/kg of body weight, IM) on serum osteocalcin concentration was studied. Two groups of horses were investigated and included clinically normal horses (group 1, n = 5) and horses with chronic obstructive pulmonary disease (group 2, n = 5). Before treatment, results of a t-test did not reveal any significant difference in serum osteocalcin concentration between the 2 groups. After treatment, a significant (P < 0.05) decrease in serum osteocalcin concentration was observed for both groups. Osteocalcin concentration in individual horses reached a min...
Peyron JG.Viscosupplementation (restoring the rheological properties of a tissue matrix) by injection of hyaluronan into the joints has been in use for 2 decades, mostly for osteoarthritis (OA) of the knee, using doses of 20-25 mg of hyaluronan of 500,000 to 2,500,000 M(r), in sequences of 2 to 10 weekly injections. Pain relief appears in a few days, progresses over a few weeks, and often lasts several months. Some data suggest the benefit can last 6 months to one year. Tolerance is universally reported as very good. Those responding to hyaluronan are 65-80%, compared to 30-35% responding to control. Co...
Bell BT, Baker GJ, Foreman JH, Abbott LC.The frequency of communication between the tarsometatarsal and distal intertarsal joints was investigated in 27 horses and 12 ponies. After the injection of diluted latex into the tarsometatarsal joints using the plantarolateral approach, the horses and ponies were walked for 200 meters. Latex was found in the distal intertarsal joints of 19 of 73 tarsi (26% communication) at necropsy. In 3 tarsi, latex was also found in the proximal intertarsal and tarsocrural joints.
Stockert JC, Trigoso CI, Tato A, Ferrer JM.The structure of specific granules from horse eosinophil leukocytes is still largely unknown. In this work, electron microscopical studies of horse eosinophils reveal that the large cytoplasmic granules contain an external membrane, a matrix of less density, and a dense (non crystalline) core. Round vacuolar inclusions of matrix materials were often observed within the cores. Horse eosinophil granules showed a considerable heterogeneity, and three morphological types could be identified according to structural features of the core and matrix.
Delbeke FT, Teale P, Debackere M, Houghton E.A commercially available generic promazine ELISA kit is available which shows cross-reactivity for the tranquilizer chlorprothixene (CPT). The ELISA test readily detects the presence of CPT or its metabolites in equine urine for up to 24 h after the i.v. and i.m. administration of sub-therapeutic doses (4.5 mg) to three horses. Maximum concentrations (CPT equivalents) are obtained 2 h after i.v. dosing. No distinct concentration peak values are observed after i.m. administration. Following solid-phase extraction, confirmation of CPT and its metabolites by electron impact mass spectrometry afte...
Vanderwall DK, Woods GL, Weber JA, Lichtenwalner AB.Transrectal ultrasonography was used to test the hypothesis that prostaglandin E(2) (PGE(2)) would increase the uterine transport of simulated embryonic vesicles in mares. Uterine transport of PGE(2)-releasing (PGE) vesicles, vehicle-releasing (sham) vesicles, and equine embryos was contrasted on Day 12 or Day 13 post ovulation. In Experiment 1, there was no difference (P>0.10) in transport of PGE vesicles, sham vesicles, Day-12 embryos, and Day-12 embryos after cervical manipulation (n = 3 per group). In Experiments 2 and 3, respectively, transport of PGE and sham vesicles was contrasted with...
Ball BA, Brinsko SP, Thomas PG, Miller PG, Ellington JE.Development of 1- to 2-cell in vivo fertilized equine embryos cultured with or without uterine tubal epithelial cells (UTEC) was studied. One- to 2-cell embryos (n = 26) were collected surgically from the uterine tubes of pony mares 1 day after ovulation. Four- to 8-cell embryos (n = 9) were collected 2 days after ovulation. Presumptive zygotes and 2-cell embryos were cultured with (n = 17) or without (n = 9) UTEC, and all 4- to 8-cell embryos were cocultured with UTEC as positive controls. Uterine tubal epithelial cells were used as cell suspensions within 2 weeks after initiation of cultures...
Hope E, Johnston SD, Hegstad RL, Geor RJ, Murphy MJ.A commercially available radioimmunoassay kit for measurement of human osteocalcin was validated for use in horses. For accurate measurement of equine serum osteocalcin, blood samples may be collected at a temperature between 20 and 25 C, then centrifuged within 90 minutes; serum may be stored at -20 C in plastic tubes for up to 26 weeks. Serum may be thawed and refrozen up to 5 times without significant change in measured equine serum osteocalcin concentration. Assay sensitivity was 0.16 ng/ml. Recovery of bovine osteocalcin standard added to equine serum was linear. Intra-assay coefficient o...
Godber LM, Brown CM, Mullaney TP.A 13-year-old American Saddlebred mare was presented with a 4-day history of anorexia. Physical examination revealed increased inspiratory effort and bony enlargement of the distal limbs. Radiographs indicated a thoracic mass and periosteal proliferations on the distal limbs consistent with hypertrophic osteopathy. Gastric endoscopy revealed distal esophageal and gastric ulceration, and functional pyloric stenosis. Abdominal ultrasonographic examination revealed multiple large, cystic structures associated with the liver. A percutaneous biopsy indicated the thoracic mass to be a granular cell ...
Hofferer S, Lecompte F, Magallon T, Palmer E, Combarnous Y.Pharmacological control of reproduction in mares requires the use of equine gonadotrophins to avoid induced immunological resistance. Crude equine gonadotrophins (CEG) have been used but the presence of equine luteinizing hormone (eLH) and follicle-stimulating hormone (eFSH) in CEG has led to disappointing results in superovulation studies. Separation of eLH and eFSH activities from CEG is necessary to overcome this problem. The hydrophobic properties of the two hormones were sufficiently different to permit their separation by hydrophobic interaction chromatography (HIC) on a phenyl Sepharose...
Holyoak GR, Little TV, McCollam WH, Timoney PJ.The relationship between stage of reproductive tract maturity and susceptibility to the experimental establishment of persistent infection with equine arteritis virus (EAV) was investigated in 21 prepubertal and 15 peripubertal colts. Five of six prepubertal colts inoculated intranasally remained infected in the reproductive tract from post-challenge day 28 to 93 and two of six from post-challenge day 120 to 180. No virus was detected in five of these animals killed on post-challenge day 210. Each of two peripubertal colts remained infected in the reproductive tract at post-challenge day 60 an...
Couto MA, Harwig SS, Lehrer RI.Equine neutrophil antimicrobial peptide 2 (eNAP-2), a recently described antimicrobial peptide isolated from equine neutrophils, was found to selectively inactivate microbial serine proteases (subtilisin A and proteinase K) without inhibiting mammalian serine proteases (human neutrophil elastase, human cathepsin G, and bovine pancreatic trypsin). Although the primary structure of eNAP-2 resembled that of several known antiproteases that belong to the 4-disulfide core peptide family, this pattern of selectivity is unique. eNAP-2 formed a noncovalent complex with native subtilisin A or proteinas...
Baker SJ, Gerring EL.Gastric pH was monitored in neonatal foals from birth to 3 months of age. Background pH decreased, especially during the first week of life. Milk had complex effects that depended on pH prior to sucking, confounded by the age of the foal: nearly neutral background pH tended to be acidified after milk intake; moderately acid background pH tended to be neutralized; low background pH was only slightly increased by milk. Absolute magnitude of the effects of milk decreased with age. Existence of a proulcerative intragastric environment in preweaning foals is postulated, but this must be considered ...
Ikenaga H, Mizuta Y, Ono K, Sawazaki T, Suzuki N, Tomoda I.The placental and plasma cystine aminopeptidase (CAP) in pregnant animals was examined on stability after the treatment with L-methionine, ethylene diamine tetra-acetic acid (EDTA) and heat. Inhibitory effects of these treatments on enzyme activities were different among CAPs from the animal species, however, significant correlation in those effects between placental and plasma CAPs was observed. These results suggested that plasma CAP might reflect placental CAP and seemed to be available for estimating maternal gestational conditions.
Tolliver SC, Lyons ET, Drudge JH, Stamper S, Granstrom DE.Critical tests were conducted in horses (n = 11) with naturally acquired infections of benzimidazole (BZ)-resistant population-B small strongyles in 1989 and 1990. Anthelmintics administered were thiabendazole (44 mg/kg of body weight, n = 4), oxibendazole (10 mg/kg, n = 3), and oxfendazole (OFZ, 10 mg/kg; n = 4). All compounds were paste formulations administered orally except for 1 of the OFZ treatments, which was a suspension formulation given by stomach tube. Aggregate mean efficacy was calculated for all species of small strongyles, drug-resistant and non-resistant. The highest efficacy w...
Burns GA, Cummings JF.The pelvic flexure portion of the equine large colon is the proposed location of a pacemaker mechanism. This study was conducted to ascertain whether the distribution of certain putative neurotransmitters differs at the pelvic flexure compared to other sampling sites. Tissue samples were collected from the intestinal tracts of six horses. Serial sections from these samples were reacted with primary antisera specific for substance P, vasoactive intestinal polypeptide (VIP), methionine-Enkephalin, and calcitonin gene-related peptide (CGRP). The regional distribution of immunoreactive neuronal el...
Joujou-Sisic K, Granérus M, Wetterling H, Wikström K, Engström W, Jeffcott L, Schofield PN, Welin A.The expression of the insulin like growth factor (IGF) II gene has been examined in the developing equine fetus. It was found that IGF II transcripts were present in abundant quantities in third trimester embryonic and extraembryonic tissues as for example the placenta. The expression of the IGF II gene was high in the fetal liver where two prominent transcripts--4.6 and 4.1--kB were produced. However, these transcripts could not be traced in the adult liver. Instead we found two different transcripts with the sizes of 4.0 and 2.9 kB in the adult liver. These findings taken together with the d...
Post F, Doster W, Karvounis G, Settles M.The geminate recombination kinetics of CO-myoglobin strongly deviates from single exponential behavior in contrast to what is expected for unimolecular reactions (1). At low temperatures, this result was attributed to slowly exchanging conformational states which differ substantially in barrier height for ligand binding. Above 160 K the kinetics apparently slow down with temperature increase. Agmon and Hopfield (2) explain this result in terms of structural relaxation perpendicular to the reaction coordinate, which enhances the activation energy. In their model, structural relaxation homogeniz...
Slater JD, Gibson JS, Field HJ.Both intranasal (i.n.) and intracerebral (i.c.) inoculation of mice with wild-type equine herpesvirus type 1 (wt EHV-1) caused clinical signs and mortality. Virus could be recovered from target organs (turbinates, lungs and blood) for several days. By contrast, the thymidine kinase (TK)-deficient deletion mutant PR1 produced markedly less clinical disease following both i.n. and i.c. inoculation, and, in particular, no mortality occurred. PR1 did, however, establish productive infections following either route of inoculation. High titres of virus were recovered from target organs although viru...
Neely DP, Hughes JP, Stabenfeldt GH, Evans JW.Intrauterine saline infusion in the dioestrous mare shortened the ovulatory interval by inducing premature luteolysis. Plasma progestagen levels began to decrease approximately 1 day after the infusion and had declined to less than 1-0 ng/ml in 4 days. The CL, including others formed from ovulations during dioestrus, must be 4 to 5 days old before intrauterine saline will induce luteolysis. Of 10 mares infused on Day 4 or 5 after ovulation, only six had a shortened ovulatory interval. Of 10 mares infused on Day 6 or 7 after ovulation, seven had a shortened ovulatory interval and three failed t...
Gustafsson K, Tatz AJ, Dahan R, Britzi M, Soback S, Sutton GA, Kelmer G. The aim of this study was to determine the time (T) to the maximum concentration (C) of amikacin sulphate in synovial fluid of the radiocarpal joint (RCJ) following cephalic intravenous regional limb perfusion (IVRLP) using 2 g of amikacin sulphate. Methods: Cephalic IVRLP was performed with 2 g of amikacin sulphate diluted in 0.9% NaCl to a total volume of 100 mL in six healthy adult mixed breed mares. An Esmarch's rubber tourniquet was applied for 30 minutes and the antibiotic solution was infused through a 23-gauge butterfly catheter. Synovial fluid was collected from the RCJ ...
Ellerbrock RE, Canisso IF, Roady PJ, Litsky A, Durgam S, Podico G, Li Z, Lima FS.A recent study demonstrated that enrofloxacin and ciprofloxacin cross the equine placenta without causing gross cartilage or tendon lesions in the 9-month fetus; however, long-term effects of in utero fluoroquinolone exposure remain unknown. Objective: To assess effects of fetal exposure to enrofloxacin on the resulting foal's cartilage and tendon strength. Methods: Healthy mares at 280 days' gestation were allocated into four groups: untreated (n = 5), therapeutic treatment (7.5 mg/kg enrofloxacin, PO × 14 days, n = 6), supratherapeutic treatment (15 mg/kg, PO × 14 days, n = ...
Cheetham J, Regner A, Jarvis JC, Priest D, Sanders I, Soderholm LV, Mitchell LM, Ducharme NG.Bilateral vocal fold paralysis (BVCP) is a life threatening condition and appears to be a good candidate for therapy using functional electrical stimulation (FES). Developing a working FES system has been technically difficult due to the inaccessible location and small size of the sole arytenoid abductor, the posterior cricoarytenoid (PCA) muscle. A naturally-occurring disease in horses shares many functional and etiological features with BVCP. In this study, the feasibility of FES for equine vocal fold paralysis was explored by testing arytenoid abduction evoked by electrical stimulation of t...
Geiser DR, Rohrbach BW.End-tidal carbon dioxide tension (PetCO2) and arterial carbon dioxide tension (PaCO2) were determined and compared in isoflurane-anesthetized spontaneously breathing equine neonates. End-tidal carbon dioxide and PaCO2 values increased with respect to time. Difference between values of PetCO2 and PaCO2 increased over time. End-tidal carbon dioxide tension was useful to predict changes in and was more closely correlated with PaCO2 early in the anesthetic period (T less than or equal to 60 minutes). The dead space volume to tidal volume (Vd/Vt) ratio increased with respect to time, indicating inc...
Auer DE.The role of oxygen-derived free radicals is considered critical to the etio-pathogenesis of equine inflammatory joint disease. In vivo, the superoxide radical in the joint may be derived either from activated polymorphonuclear leukocytes or from an ischemia/reperfusion cycle. In the presence of ferrous iron, it may generate the highly reactive hydroxyl radical (OH *). Predisposing factors may include synovitis, exercise-induced ischemia and minor traumatic injury to the joints. Unlike other inflammatory mediators, oxygen-derived free radicals may damage tissue directly and these reactive speci...
Grosenbaugh DA, Amoss MS, Hood DM, Williams JD.A heterologous radioreceptor binding assay (RRA) has been developed capable of detecting nanogram amounts of epidermal growth factor (EGF) receptor-binding activity in equine urine. The binding parameters of [125I]mEGF (murine EGF) to EGF receptors on equine plasma membranes are in good agreement with values from other EGF-RRA systems. The dissociation constant estimated from equilibrium methods (KD = 4 X 10(-10) M) is in reasonable agreement with that determined from the rate constants (KD = 6 X 10(-10) M) and is in good agreement with values determined in other species. The assay is specific...
López ML, de Souza W.The presence and distribution of cholesterol in mature and immature epididymal spermatozoa was analyzed using filipin as a cytochemical tool in freeze-fracture replicas and thin section preparations. The polyenic-antibiotic filipin formed complexes with 3, beta -OH sterols, producing characteristic protrusions, or pits, that were heterogeneously distributed in the plasma membrane of stallion spermatozoa, revealing a specific organization in a functionally specialized area of the gamete. The acrosomal region of the sperm head presented a significantly higher density of filipin sterol complexes ...
Morrissey NK, Bellenger CR, Ryan MT, Baird AW.To measure the expression of cyclooxygenase-2 (COX-2) mRNA in gastric biopsy specimens serially obtained from horses before, during, and after an 8-day intermittent feed-deprivation trial and to investigate the mucosal location of COX-2. Methods: 9 mixed-breed horses for retrieval of gastric biopsy specimens and 16 additional horses for immunohistochemical analysis. Methods: Gastric biopsy specimens were obtained from 6 horses; 3 of these horses and 3 more participated in an intermittent feed-deprivation trial 9 weeks later. A quantitative PCR assay was used to determine the amount of COX-2 mR...
Arias MS, Piñeiro P, Hillyer GV, Francisco I, Cazapal-Monteiro CF, Suárez JL, Morrondo P, Sánchez-Andrade R, Paz-Silva A.The utility of an enzyme-linked immunosorbent assay to determine the sensitization against the trematode Fasciola hepatica in horses from an endemic area (NW Spain) was assessed. Blood samples were collected from 536 horses and tested against a 2.9-kDa recombinant surface protein (FhrAPS) to estimate the presence of IgG antibodies. Data were analysed regarding several intrinsic (age, gender and breed) and extrinsic factors (aptitude and housing). The farm size (number of horses/farm) was also considered. Sixty percent (95% CI 56, 64) of the horses were positive to the FhrAPS-ELISA, with a sign...
Moudgal NR, Papkoff H.The ability of equine luteinizing hormone (eLH) to promote follicular growth and maturation in hypophysectomized rats has been assessed. A single injection of equine LH has been shown to promote the growth of a large number of antral and preovulatory follicles. In addition, equine LH markedly increased serum estrogen levels and uterine weight. Furthermore, equine LH, like equine chorionic gonadotropin (eCG; PMSG) was able to significantly enhance the incorporation of [3H]thymidine into ovarian DNA, an activity shown to be specific to hormones having follicle-stimulating hormone (FSH) activity....
Chidlow H, Giguère S, Camus M, Wells B, Berghaus R, McConachie Beasley E.Serial cerebrospinal fluid (CSF) analysis might be required in clinical neurologic disease. The effect of lumbosacral (LS) or cervical (C1-C2) centesis on subsequent CSF cytologic analyses has not been investigated in horses. Objective: To evaluate the effect of thecal puncture on subsequent CSF analyses ANIMALS: Ten healthy adult horses. Methods: Prospective study. Horses were randomly assigned to undergo CSF collection twice, 14 days apart, from either the C1-C2 or LS space. After a 4-month washout period, CSF collection was repeated from the alternate site. Continuous data were analyzed u...
Rodriguez J, Maserati M, Robilotta T, Augusto G, Alonso MA, Redoan M, Tibary A, Fleury P.Field collection of oocytes in mares using transvaginal follicular aspiration (TVA) for embryo production has the potential to revolutionate the equine industry. Protocols for TVA in specialized laboratory settings have been described in the scientific literature since the early 1980s. The objective of this study was to determine the success rate of TVA oocytes recovery under ambulatory conditions. A secondary goal of this study was to determine if TVA is associated with any health complications when performed by recently trained practitioners in the field. Follicles (n = 296) from 66 adult c...
von Reitzenstein M, Callahan MA, Hansen PJ, LeBlanc MM.An experiment was conducted to determine whether the uterotonic effects of oxytocin, a drug used to treat mares that have a delay in uterine clearance were affected by the sedative detomidine (an alpha2-agonist), a drug used to treat fractious mares. An additional objective was to identify propagation patterns of uterine contractions and determine whether these patterns differed between normal mares and mares with delayed uterine clearance (DUC). Intrauterine pressure was measured in five reproductively normal mares and four mares with DUC during estrus using an 8-F Milar catheter with two dis...
Niedzwiedz A, Slawuta P, Zak A, Slowikowska M, Siwinska N, Rykała M, Nicpon J.Equine asthma syndrome is an allergic, inflammatory airway disease that usually affects older horses. Respiratory acidosis is an acid-base imbalance caused by alveolar hypoventilation. The acid-base balance may be assessed using the Henderson-Hasselbalch equation as well as the Stewart model. The authors hypothesized that systemic respiratory acidosis changes the ionic concentrations affecting water dissociation. The study group included 16 Warmblood, mixed breed horses of both sexes with a history of severe equine asthma, and 10 healthy horses were used as controls. Arterial and venous blood ...
Zabel S, Mueller RS, Fieseler KV, Bettenay SV, Littlewood JD, Wagner R.The records of 15 horses with pemphigus foliaceus diagnosed on the basis of their history, clinical signs, histopathology and the exclusion of differential diagnoses were evaluated with respect to the age of onset, the clinical signs and the diagnostic tests used. There was no apparent breed predisposition. The horses' mean age was nine years, with a range from three months to 25.5 years, three were foals up to six months old and eight were nine years old or older. The most frequent lesions were scaling in 11, crusting in 10 and alopecia in 10, and they appeared most commonly on the face, neck...
Quam V, Yardley J, Quam M, Paz C, Belknap J.The analgesic effect of cryotherapy in an induced lameness model was evaluated. Lameness was induced with solar pressure from a custom-made shoe in a 10-horse, cross-over study. The degree of lameness was recorded with a commercial non-invasive inertial sensor. The distal limbs were maintained in an ice and water slurry (cryotherapy) or at ambient temperature (control) for 1 hour. Lameness was assessed serially over the following hour. Lameness at each time point was compared to the baseline induced lameness, within and between groups. Lameness had improved significantly in all horses 5 minute...
Gracia-Calvo LA, Ezquerra LJ, Ortega-Ferrusola C, Martín-Cuervo M, Tapio H, Argüelles D, Durán ME.In order to know reproduction-related complications due to standing laparoscopic peritoneal flap hernioplasty, histological characteristics of the testicles from five stallions one year after surgery were compared with seven testicles from four healthy stallions. Moreover, the daily sperm output (DSO) was determined before (T0) and one year after surgery (T12). DSO did not show significant differences between T0 and T12. The diameter of the seminiferous tubules was significantly decreased in the samples from the hernioplasty group. The percentage of tubules with full spermatogenesis was smalle...
Brown MP, Trumble TN, Merritt KA.To investigate effects of osteochondral injury on high-mobility group box chromosomal protein 1 (HMGB-1) concentrations in synovial fluid (SF) from Thoroughbreds and to compare these results with radiographic and arthroscopic scores of severity of joint injury. Methods: 40 clinically normal rested Thoroughbreds (group 1) and 45 Thoroughbreds with osteochondral injury as a result of racing. Methods: SF was obtained from the metacarpophalangeal (MCP) joints, metatarsophalangeal (MTP) joints, middle carpal joints, and radiocarpal joints. For group 2, radiographic and arthroscopic scores were dete...
Wagner B, Siebenkotten G, Leibold W, Radbruch A.Due to characteristic clinical signs, immunoglobulins of isotype E (IgE) are believed to be involved in several allergic diseases of the horse. To date, closer investigations have been hampered by the fact that neither purified equine IgE nor anti-equine IgE monoclonal antibodies were available for IgE isotype determination. As an approach to solve this problem, we constructed a stable cell line (EqE6) that expresses recombinant equi-murine IgE specific for 4-(hydroxy-3-nitro-phenyl) acetyl (NP). Biochemical analysis of the purified protein revealed a highly glycosilated IgE monomer of approxi...
Recio P, Prieto D, Martínez MP, García P, Rivera L, Benedito S, Martínez AC, Sacristán AG, Orensanz LM, Hernández M.Our aim was to study the presence of noradrenergic nerves and to characterize the alpha-adrenergic receptors involved in the contractions to electrical field stimulation and to alpha-adrenergic agonists of the horse penile deep dorsal vein. Noradrenergic fibres were visualized by immunohistochemistry using an antibody against dopamine-beta-hydroxylase (DBH). For functional studies, the responses of the venous rings to electrical field stimulation and to alpha-adrenergic agonists (noradrenaline, phenylephrine and BHT 920) were studied in the absence and the presence of noradrenergic transmissio...
Horohov DW, Loynachan AT, Page AE, Hughes K, Timoney JF, Fettinger M, Hatch T, Spaulding JG, McMichael J.Rhodococcus equi is a soil borne bacterium that causes severe morbidity and death in young foals. The economic costs of the disease include loss of life, treatment expenses, veterinary monitoring expenses and, perhaps most importantly, potential reduction in future athletic performance in horses that suffer severe lung abscessations caused by R. equi. Current standard of care for pneumonia caused by R. equi is treatment with a macrolide antimicrobial and rifampicin. However, the hallmark of pneumonia caused by R. equi is severe formation of pyogranulomas and a walling off effect that can preve...
Maede Y, Inaba M, Amano Y, Murase T, Goto I, Itakura C.Cryoglobulin was isolated from a horse which had glomerulo-nephritis and a history of swelling and skin ulcers of the limbs in the winter. The isolated cryoglobulin showed a single peak on a gel permeation chromatography column with an apparent molecular mass (Mr) of 180,000 which could be divided into two gamma bands by cellulose acetate electrophoresis. Immunoelectrophoretic analysis revealed that the cryoglobulin formed two precipitation lines with anti-horse IgG. Spur formation was observed when the cryoglobulin and the IgG purified from a normal healthy horse were cross-reacted with anti-...
Cargile JL, MacKay RJ, Dankert JR, Skelley L.Tumor necrosis factor-alpha (TNF) is an important mediator of endotoxin-induced pathologic changes. To help define the role of TNF in equids with endotoxemia, the effects of pretreatment with a murine monoclonal antibody (MAB) against equine TNF were evaluated in Miniature Horses given endotoxin. Five horses were given TNF MAB at a dosage of 1.86 mg/kg of body weight, IV, and 5 were given control MAB. Five minutes later, lipopolysaccharide (LPS; Escherichia coli O55:B5), 0.25 microgram/kg, was given to all horses by bolus IV infusion. Clinical signs of disease were monitored at intervals up to...
Pedersen HG, Watson ED, Telfer EE.During the oestrous cycle follicles grow and either ovulate or regress. Regressing follicles undergo atresia and in many species apoptosis has been identified as the underlying mechanism in this process. The aims of this study were to establish whether equine granulosa cells degenerate via an apoptotic mechanism and whether the presence of apoptotic cell death in granulosa cells is correlated with oocyte quality. Ovaries from mares at unknown stages of the oestrous cycle were obtained from an abattoir. In Expt 1, follicles (n=352) from 37 mares were processed. DNA was extracted from granulosa ...
Tozaki T, Kikuchi M, Kakoi H, Hirota KI, Mukai K, Aida H, Nakamura S, Nagata SI.Transcriptome analyses based on DNA microarray technology have been used to investigate gene expression profiles in horses. In this study, we aimed to identify exercise-induced changes in the expression profiles of genes in the peripheral blood of Thoroughbred horses using DNA microarray technology (15,429 genes on 43,603 probes). Blood samples from the jugular vein were collected from six horses before and 1 min, 4 hr, and 24 hr after all-out running on a treadmill. After the normalization of microarray data, a total of 26,830 probes were clustered into four groups and 11 subgroups showing si...
Donnelly CG, Johnson AL, Reed S, Finno CJ.Cervical vertebral compressive myelopathy (CVCM) and equine neuroaxonal dystrophy/degenerative myeloencephalopathy (eNAD/EDM) are leading causes of spinal ataxia in horses. The conditions can be difficult to differentiate, and there is currently no diagnostic modality that offers a definitive antemortem diagnosis. Objective: Evaluate novel proteomic techniques and machine learning algorithms to predict biomarkers that can aid in the antemortem diagnosis of noninfectious spinal ataxia in horses. Methods: Banked serum and cerebrospinal fluid (CSF) samples from necropsy-confirmed adult eNAD/EDM (...
Izing S, Béni D, Molnár S, Bakos Z, Bodó G.The objectives of this in vivo experimental study were to evaluate the feasibility of cortical screw insertion into the intact distal phalanx in standing sedated horses and to document potential postoperative complications. One cortical screw was randomly inserted in lag fashion into each distal phalanx in 9 horses. The second surgery on the contralateral limbs was performed 2-3 weeks after the first operation, when a 4.5-mm cortical screw was inserted in lag fashion into the distal phalanx of sedated horses following perineural analgesia. Following surgery, the drill hole was filled with an a...
Hall MS, Pollock PJ, Russell T.To document the progression and outcome after surgical curettage of septic physes in foals. Methods: Case series of 17 foals, aged <9 weeks, with septic physitis. Methods: All foals were treated surgically with curettage of physeal lesions. Combinations of systemic antibiotics, intravenous regional perfusion of antibiotic and antibiotic-impregnated polymethylmethacrylate beads were used as adjunct medical treatments. Tissue removed from the physis of three foals during surgery was sent for pathological analysis. Results: At follow-up, 15 of the 17 foals were alive. In the two foals with sep...
Spensley MS, Baggot JD, Wilson WD, Hietala SK, Mihalyi JE.Plasma and endometrial tissue concentrations of ticarcillin were measured in healthy mares. In the first of the 3 separate phases comprising the study, ticarcillin disodium (30 mg/kg) was administered IV. The mean peak concentration in endometrial tissue, 12.9 micrograms/g, was attained at 30 minutes. The plasma half-life of the drug in the 6 mares was 0.83 +/- 0.22 hour. Six grams of the drug was diluted in 250 ml of sodium chloride injection USP (2nd phase) and in 60 ml of sodium chloride injection USP (3rd phase). These dilutions were administered by intrauterine infusion. In phase 2, the m...
