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.
Chilcoat CD, Rowlingson KA, Jones SL.Toxic products such as reactive oxygen intermediates released by activated polymorphonuclear neutrophil (PMN) have an important role in the pathophysiology of diseases associated with the deposition of immune complexes (IC) in tissues. IC-induced activation of PMN requires adhesion mediated by integrin adhesion receptors. Of the integrins expressed on PMN, the beta(2) family has been found to be of particular importance for activation of PMN by IC. beta(2) Integrin ligand binding must be activated to enable adhesion to IC. Both activating and inhibitory signals regulate beta(2) integrin ligand...
Hinrichs K, Love CC, Brinsko SP, Choi YH, Varner DD.Three experiments were conducted to evaluate the effect of oocyte and sperm treatments on rates of in vitro fertilization (IVF) in the horse and to determine the capacity of in vitro-matured horse oocytes to be fertilized in vivo. There was no effect of duration of oocyte maturation (24 vs. 42 h) or calcium ionophore concentration during sperm capacitation (3 microM vs. 7.14 microM) on in vitro fertilization rates. Oocytes matured in 100% follicular fluid had significantly higher fertilization (13% to 24%) than did oocytes matured in maturation medium or in 20% follicular fluid (0% to 12%; P <...
Collins ND, LeRoy BE, Vap L.Extremely high bicarbonate (HCO3-) and anion gap values were measured in two horses and a calf using the Hitachi 911 automated serum biochemistry analyzer. All three animals had severe muscle disease as evidenced by markedly increased aspartate aminotransferase and creatine kinase activities. Laboratory error was suspected as the source of the increased HCO3- because values calculated from blood gas analysis were normal. It was hypothesized that increased serum lactate dehydrogenase (LDH) activity and pyruvate concentration overwhelmed the oxamate LDH inhibitor in the enzymatic HCO3- assay, re...
Steffey EP.Both desflurane and sevoflurane offer theoretical and practical advantages over other inhalation anesthetics for horses. The lower solubility of both agents provides improved control of delivery and helps to counteract the confounding influence of the voluminous patient breathing circuit commonly used for anesthetizing horses. The lower solubility should account for faster rates of recovery compared with the older agents; whether or not the quality of recovery differs remains to be objectively evaluated in a broad range of circumstances. The pharmacodynamic effects are, in large part, similar ...
Iqbal J, Edington N.Equid herpesvirus 1 (EHV-1) is the most common cause of virus-induced abortion in horses. After primary infection the virus becomes latent predominantly in the respiratory tract lymph nodes and the genome can also be detected in the peripheral nervous system. The role of mouse as a feasible model for the establishment of latency and reactivation of EHV-1 was investigated. Intracerebral and intranasal infections of 3- and 17-day-old mice were made and virus replication was confirmed by virus isolation and detected by indirect immunofluorescence (IIF) in brain. For reactivation studies, the mice...
Weiss DJ, Evanson OA.To evaluate lipopolysaccharide (LPS)-induced activation of equine neutrophils in blood. Methods: Blood samples from 5 healthy adult Thoroughbreds. Methods: Neutrophil integrin (CD11/CD18) expression, size variation, degranulation, and deformability were measured with and without incubation with LPS. Time and concentration studies were done. The mechanism of endotoxin-induced neutrophil activation was investigated by inactivating complement or preincubating neutrophils with inhibitors of tumor necrosis factor-alpha (TNF-alpha) synthesis, prostaglandin-leukotriene synthesis, or platelet-activati...
Lindberg A, Näsman-Glaser B, Lindgren JA, Robinson NE.To evaluate leukotriene (LT) biosynthetic capacity in lung tissue from healthy horses and horses with recurrent airway obstruction (RAO). Methods: Lung parenchyma and airway specimens from 8 RAO-affected and 5 healthy horses. Methods: Horses were stabled for > or = 72 hours. Blood was drawn before euthanasia, after which lung specimens were collected. Tissue strips from small airways and parenchyma were incubated in organ baths with the precursor LTA4 or stimulated with calcium ionophore A23187 or the tripeptide N-formyl-Met-Leu-Phe (fMLP), with or without exogenous arachidonic acid, in the...
Finley MR, Li Y, Hua F, Lillich J, Mitchell KE, Ganta S, Gilmour RF, Freeman LC.In dogs and in humans, potassium channels formed by ether-a-go-go-related gene 1 protein ERG1 (KCNH2) and KCNQ1 alpha-subunits, in association with KCNE beta-subunits, play a role in normal repolarization and may contribute to abnormal repolarization associated with long QT syndrome (LQTS). The molecular basis of repolarization in horse heart is unknown, although horses exhibit common cardiac arrhythmias and may receive drugs that induce LQTS. In horse heart, we have used immunoblotting and immunostaining to demonstrate the expression of ERG1, KCNQ1, KCNE1, and KCNE3 proteins and RT-PCR to det...
Mader Ch, Geisel O, Gerhards H, Hermanns W.In the present work transponders of 2 identification systems have been implanted on an exactly defined site at the bottom of the ear on 28 horses. The Backhome system is easier to handle and less complicated than the trovan system since it is smaller and handier. The hemorrhages that had occurred after the injection were mild at 17 animals and moderate at 4 animals. Inflame changes at the injection site post application were limited to minor swellings (n = 3) and minor pain (n = 6). The interrogator's scope of the two transponder systems is different. The interrogator's scope of the trovan tra...
Miller TL, Lin C.Formal nomenclature is proposed for five methanogens, isolated from horse, pig, cow, goose and sheep faeces, that represent four novel species of the genus Methanobrevibacter. The four species, Methanobrevibacter gottschalkii sp. nov., Methanobrevibacter thaueri sp. nov., Methanobrevibacter woesei sp. nov. and Methanobrevibacter wolinii sp. nov., are distinguished from each other by a lack of genomic DNA reassociation and from previously described members of the genus on the basis of differences in the sequences of the 16S rRNA genes.
Colahan PT, Bailey JE, Chou CC, Johnson M, Rice BL, Jones GL, Cheeks JP.Twelve clinically sound, healthy, athletically conditioned Thoroughbred horses were subjected to an incremental exercise stress test to determine the effects and period of detection of a single dose of flunixin meglumine (1.1 mg/kg by intravenous injection) in serum and urine by ELISA. Flunixin concentrations, performance, and hematologic and clinical chemical parameters were measured. All horses were rotated through four treatment groups of a Latin-square design providing for each horse to serve as its own control. Flunixin meglumine reduced prostaglandin F(1alpha) and thromboxane concentrati...
McManus CJ, Davison LA, Fitzgerald BP.In a variety of species, glucoprivation results in the suppression of the reproductive axis. Two experiments were performed to test the hypothesis that blockade of glucose metabolism via administration of the glucose inhibitor 2-deoxy-D-glucose (2DG) to mares would cause a modification in gonadotropin and prolactin secretion. Long-term ovariectomized mares (Experiment 1, n=4) or ovary-intact mares during the follicular phase of a synchronized estrous cycle (Experiment 2, n=4 per dose) were treated with 2DG. The dose of 2DG used in Experiment 1 was 100mg 2DG/kg BW, but because severe behavioral...
Bøgh IB, Bézard J, Duchamp G, Baltsen M, Gérard N, Daels P, Greve T.In the mare, rates of fertilization and development are low in oocytes matured in vitro, and a closer imitation of in vivo conditions during oocyte maturation might be beneficial. The aims of the present study were, therefore, to investigate whether (1) equine oocytes can be matured in vitro in pure equine preovulatory follicular fluid, (2) priming of the follicular fluid donor with crude equine gonadotrophins (CEG) before aspiration of preovulatory follicular fluid promotes the in vitro maturation rate, (3) the in vitro maturation rate differs between oocytes aspirated during estrus and those...
Bailey MT, Troedsson MH, Wheato JE.The hormone-producing equine granulosa cell tumor (GCT) may secrete high levels of inhibin. Measurement of inhibin concentrations may be useful in the diagnosis and conformation of mares with GCT. Inhibin may be measured using RIA, which recognizes dimeric alphabetaA-inhibin as well as the monomeric (free) inhibin alpha-subunit, or using a two-site immunoradiometric assay (IRMA) specific for alphabetaA-inhibin. The objective of this study was to examine concurrent relationships among alpha-inhibin (as measured using RIA), alphabetaA-inhibin (as measured using IRMA), and other hormones (testost...
Horín P, Matiasovic J.More than two nucleotide sequences of the second exon of the ELA-DQB region retrieved from a single animal and two different sequences isolated from horses homozygous in the major histocompatibility complex (MHC) region by descent indicated the existence of at least two ELA-DQB loci at the genomic level. New alleles detected by polymerase chain reaction single strand conformation polymorphism (SSCP) and defined by nucleotide sequencing of the second exon of the DQB gene(s) were described. Based on the level of nucleotide sharing, at least two groups of alleles were shown to exist. The newly de...
Craigo JK, Leroux C, Howe L, Steckbeck JD, Cook SJ, Issel CJ, Montelaro RC.The genetic variation of equine infectious anaemia virus (EIAV) clearly affects the antigenic properties of the viral envelope; however, effects on immunogenicity remain undefined, although widely assumed. Here, the immunogenicity is reported of a novel, neutralization-resistant, pony-isolate envelope EIAV(PV564DeltaPND) that contains a 14-residue deletion in the designated principal neutralizing domain (PND) of the gp90 protein. Two ponies inoculated with a chimeric virus, EIAV(DeltaPND), containing the EIAV(PV564DeltaPND) envelope in a reference provirus strain, remained asymptomatic through...
Gray AW, Davies ME, Jeffcott LB.Cathepsin K and cathepsin B were immunolocalised in equine osteoclasts (OC s) present in ex vivo cartilage/subchondral bone samples. Samples were obtained post mortem from the lateral trochlear ridge (LTR) of six horses and ponies aged between 303 days gestation to 8 months. Strong expression of cathepsin K was detected in OC s, particularly those located at the osteochondral junction, apparently involved in the resorption of calcified cartilage. Cathepsin K expression was also detected in hypertrophic chondrocytes and in the endothelial cells of some blood vessels penetrating the hypertrophic...
Mobarak MS, Ryan MF.The ultrastructure of the dorsal oesophageal gland ampulla and its relationship with the oesophagus, oesophageal ultrastructure, and control mechanisms in oesophageal activity were studied. Terminal ducts of the sub-ventral glands open through the oesophageal crown at the base of the buccal cavity. The terminal duct of the dorsal oesophageal gland running through the dorsal gutter opens to the exterior at the rim 'groove' of the buccal capsule. The posterior oesophageal region is clavate and the cuticle of the lumen folds to form outlet valves, 'valvulae'. An inconspicuous oesophago-intestinal...
Bacon SJ, Ellis SA, Antczak DF.In most mammals, the fetus limits its presentation of paternal antigens to the mother by suppressing the cell-surface expression of proteins of the major histocompatibility complex (MHC) on trophoblast. In the horse, however, functional, polymorphic MHC class I antigens are expressed at high levels on the invasive trophoblast cells of the chorionic girdle between Days 32 and 36 of pregnancy, although not on the adjacent noninvasive trophoblast of the chorion and allantochorion membranes. In this study, the control of MHC class I gene expression was investigated in invasive and noninvasive hors...
Coutinho da Silva MA, Carnevale EM, Maclellan LJ, Seidel GE, Squires EL.The objective of the study was to compare embryo development rates after transfer of oocytes collected 22 or 33 h after hCG injection into recipients inseminated within the uterus or the oviduct. Oocytes were collected at approximately 22 or 33 h after hCG injections and incubated for approximately 16 or 1.5 h, respectively, before transfer. Intrauterine inseminations using 1 x 10(9) progressively motile sperm were done approximately 12 h before and 2 h after transfer. For intraoviductal inseminations (gamete intrafallopian transfer [GIFT]), semen was centrifuged through a Percoll gradient, an...
Van Hoogmoed LM, Agnew DW, Whitcomb M, Hyde DW, MacDonald MH, Snyder JR.To describe the ultrasonographic and quantitative histologic effect of injecting 2% iodine in almond oil (IAO) and ethanolamine oleate (EO) in the medial and middle patellar ligaments of horses and to determine whether a difference in response exists between IAO and EO treatment. Methods: 10 healthy horses. Methods: In 5 horses, the medial and middle patellar ligaments of 1 limb were injected with EO, whereas IAO was injected in the medial and middle patellar ligaments of another 5 horses. Ultrasonographic evaluation was performed on the experimental and control limb before injection of IAO an...
Lescun TB, Adams SB, Wu CC, Bill RP, Van Sickle DC.To determine the effects of a continuous intra-articular infusion of gentamicin on the synovial membrane and articular cartilage in the tarsocrural joint of horses. Methods: 6 healthy adult horses. Methods: A balloon infusion system attached to a catheter placed in the plantarolateral pouch of both tarsocrural joints in each horse was used for continuous gentamicin solution (GM) or balanced electrolyte solution (BES) delivery for 5 days. Cartilage and synovial membrane specimens were collected on day 5 from 3 horses and on day 14 from the remaining 3 horses. Both infused joints from each horse...
Widenhouse TV, Lester GD, Merritt AM.To determine the effect of pH with or without pepsin or taurocholic acid on the bioelectric properties of gastric squamous mucosa in horses. Methods: Gastric tissues obtained from 16 adult horses that did not have evidence of gastric disease. Methods: Bioelectric properties of squamous mucosa were determined, using modified Ussing chambers. Tissues then were exposed to mucosal pepsin (1 mg/ml) or taurocholic acid (2.5 mM) under neutral (pH 74) or acidic (pH 1.7) conditions. Results: Exposure of mucosal sheets to an acidic pH resulted in an immediate and sustained decrease in transmembrane pote...
Gokbulut C, Nolan AM, McKellar QA.Oxibendazole (OBZ) was administered to eight horses at an oral dose of 10 mg kg(-1) bodyweight each. Parent OBZ could only be detected in plasma at the 0.5 and 1.0 hours post administration sampling times and the mean maximum plasma concentration was 0.008 microg ml(-1). Parent OBZ was detected in faeces between 12 and 72 hours after administration and the highest dry faecal concentration was detected at 24 hours. An unidentified metabolite was detected in plasma between 0.5 and 72 hours. The unidentified metabolite in the plasma of treated horses corresponded to the second eluted metabolite i...
Nell A, James SA, Bond CJ, Hunt B, Herrtage ME.This study aimed to investigate the distribution of Malassezia species yeasts on the skin of healthy horses. Acetate tape samples were obtained from the lip, axilla, interbulbar region, groin and anus of 12 healthy horses. The samples were stained and examined microscopically and sites harbouring yeast-like organisms were identified. Contact plates were applied to the skin at these sites and cultured at 26 degrees C and 32 degrees C. No growth was obtained on horse blood, Sabouraud's dextrose or modified Dixon's agar. A pure growth of a Malassezia-type organism was obtained on Sabouraud's dext...
Armstrong S, Lees P.Chondrocytes and synoviocytes harvested from the joints of healthy horses were maintained in tissue culture. Production of the cytokines interleukin-1 (IL-1), interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-alpha) in response to lipopolysaccharide (LPS), and the effects of addition of carprofen (racemate and R and S enantiomers) were determined. Lipopolysaccharide failed to stimulate TNF-alpha activity in both cell types but concentrations of IL-1 and IL-6 were both increased in a concentration and time-related manner. Both carprofen enantiomers and the racemic mixture attenuated th...
Knoll U, Strauhs P, Schusser G, Ungemach FR.Olsalazine sodium (Dipentum*) has been used therapeutically against inflammatory bowel disease in human medicine as an alternative to sulphasalazine over the past 20 years. Bacteria in the colon split this prodrug into two molecules of the locally effective 5-aminosalicylic acid (5-ASA). Considering the potential therapeutic use in equine colitis, the pharmacokinetics of olsalazine (OLZ) after single oral administration to six horses at a dosage of 30 mg/kg was investigated. Plasma concentrations of OLZ, 5-ASA, and its main metabolite N-acetyl-5-aminosalicylic acid (Ac-5-ASA) were analysed by ...
Theoret CL, Barber SM, Moyana TN, Gordon JR.To determine whether transforming growth factor (TGF)-beta1 and -beta3 expression differs between equine limb wounds healing normally and those healing with experimentally induced exuberant granulation tissue (EGT). Methods: Six wounds were created on the lateral aspect of both metacarpi of each horse; one forelimb was untreated, and the other was bandaged to stimulate the development of EGT. Sequential wound biopsies allowed comparison of growth factor expression between the two types of wound. Methods: Four horses (2 to 4 years of age; 350 to 420 kg). Methods: Wounds were assessed grossly, h...
Theoret CL, Barber SM, Gordon JR.To describe the localization of immunoreactive transforming growth factor (TGF)-beta1 in both normal skin and full-thickness dermal wounds of the limb and the thorax of the horse. Methods: Six full-thickness excisional wounds were created on the lateral aspect of one metacarpal region and on the midthoracic area of each horse. Sequentially collected tissue specimens from wound margins were assessed for TGF-beta1 expression by immunohistochemistry. Methods: Four horses (2 to 4 years of age). Methods: A neutralizing monoclonal anti-human TGF-beta1 antibody was used to detect the spatial expressi...
Costa HM, Silva AV, Guimarães MP.This paper describes some morphological aspects of Cylicocyclus brevicapsulatus (Ihle, 1920) (Nematoda: Cyathostominae) from Equus caballus in Brazil. The worms were studied using an optical microscope (measurements and illustrations) and a scanning electron microscope for a more detailed examination of the external morphology. The buccal capsule is very short, with a very thin wall, and the dorsal gutter is absent. Other morphological aspects are described including measurement of the spicules and gubernaculum.
Magnuson NS, McGuire TC, Banks KL, Perryman LE.The in vitro and in vivo effects of corticosteroids on peripheral blood lymphocytes (PBL) from ponies were studied. Prednisolone inhibited lymphocyte stimulation by phytohemagglutin (PHA) in a dose-dependent manner, without inducing lysis even at large doses. The PBL from horses heterozygous for the combined immunodeficiency trait responded to corticosteroid treatment the same as did PBL from normal ponies. Removal of the corticosteroid after incubation with PBL from normal ponies partially restored responsiveness of these cells to PHA. Chronic in vivo treatment of ponies with corticosteroids ...
Rashmir-Raven A, Lavagnino M, Sedlak A, Gardner K, Arnoczky S.Hereditary equine regional dermal asthenia (HERDA) is a genetic disorder of collagen resulting in fragile, hyper-extensible skin and ulcerative lesions. The predominance of skin lesions have been shown to occur on the dorsum of HERDA-affected horses. While this has been postulated to be due to increased exposure to sunlight of these areas, the precise pathological mechanism which causes this to occur is unclear. Objective: We hypothesized that an increase in collagenase activity, that has been associated with the exposure of dermal fibroblasts to sunlight, will significantly degrade the materi...
Watts AE.Mesenchymal stem cells (MSCs) are used as a regenerative therapy in horses for musculoskeletal injury since the late 1990s and in some regions are standard of care for certain injuries. Yet, there is no Food and Drug Administration-approved MSC therapeutic in the United States for horses. In humans, lack of regulatory approval in the United States has been caused by failure of late-phase clinical trials to demonstrate consistent efficacy, perhaps because of nonuniformity of MSC preparation and application techniques. This article discusses clinical evidence for musculoskeletal applications of ...
Foreyt WJ, Lagerquist JE.Peripheral blood neutrophils from horses, cattle, and Rocky Mountain bighorn sheep (Ovis canadensis canadensis) were evaluated for susceptibility to cytotoxin-dependent lysis of different biotypes and serotypes of Pasteurella haemolytica of domestic sheep, cattle, bighorn sheep, or mountain goat (Oreamnos americana) origin utilizing a cytotoxicity assay which measures the degree of bacteria cytotoxin-killing of neutrophils. All isolates of P. haemolytica (biotypes A and T) were noncytotoxic to horse neutrophils. Thirteen of 18 R haemolytica biotype A isolates were cytotoxic (> 50% neutrophi...
Siwińska N, Żak-Bochenek A, Paszkowska M, Karczewski M, Długopolska D, Haider W.Colic, a condition affecting the gastrointestinal tract of horses, manifests as severe pain and may be a life-threatening condition. It is possible to distinguish between an acute, disposable process, as well as recurrent colic symptoms (abdominal pain) caused by an ongoing chronic inflammatory process. This paper presents a retrospective analysis of the histopathological findings of duodenal and rectal samples taken from horses with recurrent colic, with the aim to determine the frequency and extent of inflammation. The samples, i.e., duodenal biopsy (60 samples) and rectal biopsy (17 samples...
Fitzharris LE, Meehan LJ, Hezzell MJ, Allen KJ.The diaphragm is an important respiratory muscle, playing a key role during exercise. In humans, diaphragm thickness increases in response to training and is correlated with inspiratory strength. In order to assess respiratory strength in the horse, new evaluation techniques are required and measurement of diaphragm thickness, in a non-invasive and repeatable manner, is a possible approach. The purposes of this four-part, prospective, pilot study were to develop and describe a repeatable method to measure the diaphragm thickness, using ultrasonography, in Thoroughbred racehorses. A standardize...
Laan TT, Bull S, Pirie RS, Fink-Gremmels J.Cyclic AMP elevating agents have been shown to exhibit anti-inflammatory properties in addition to functions such as bronchodilation. The aim of this study was to investigate this dual action of clenbuterol (CB; Ventipulmin) on horses affected with recurrent airway obstruction (RAO). Seven RAO susceptible horses received inhalation challenges with aerosolised lipopolysaccharide (LPS), hay dust suspension (HDS) and Aspergillus fumigatus antigen (AF) with and without prior treatment with intravenous CB. Data showed that CB exerted significant beneficial effects on lung function, total cell count...
Greene SA, Thurmon JC, Tranquilli WJ, Benson GJ.Serum insulin and plasma glucose concentrations were determined in 8 mares. Four IV treatments were studied: xylazine (1.1 mg/kg of body weight); yohimbine (0.125 mg/kg); yohimbine (0.125 mg/kg) followed 5 minutes later by xylazine (1.1 mg/kg); and 5 ml of isotonic saline solution as a control. Blood samples were collected before (time 0) and at 5, 15, 30, 60, 120, and 180 minutes after drug administration. Serum insulin concentration decreased and plasma glucose concentration increased in mares given xylazine. Plasma glucose concentration was unchanged in control mares and in mares given yohi...
Longworth KE, Jarvis KA, Tyler WS, Steffey EP, Staub NC.Seven horses (4 anesthetized and 3 awake) and 2 ponies (anesthetized) were studied to evaluate the high sensitivity of the pulmonary circulation of the horse to various blood-borne particles, and to establish the presence of intravascular macrophages in the lung. Pulmonary and systemic pressures and cardiac output before and during particle injection were measured in some animals. An anesthetized foal had a large increase in pulmonary arterial pressure (32 and 34 mm of Hg) within 1 minute of IV administration of small test doses of radioactively labeled liposomes (2.5 mumol/kg of body weight) ...
Jago RC, Scholes S, Mair TS, Pearson GR, Pirie RS, Handel I, Milne EM, Coyle F, Mcgorum BC.An accurate, minimally invasive, ante-mortem diagnostic test for equine grass sickness (EGS) is currently lacking. Although histological examination of haematoxylin and eosin-stained rectal biopsies for chromatolytic neurons is insensitive as a diagnostic test for EGS, we hypothesised that its diagnostic accuracy could be improved by immunolabelling for β-amyloid precursor protein (β-APP), which has increased expression in cranial cervical ganglia (CCG) neuronal perikarya in EGS. Objective: To develop a grading scheme for assessing the distribution and intensity of β-APP immunoreactivity wi...
Rosser JM, Brounts S, Livesey M, Wiedmeyer K.Our objective was to compare thoracoabdominal (TA Premium™ 90) stapled enterotomy closure to traditional hand-sewn closure, using time to perform the technique, luminal diameter, and bursting pressure in ex-vivo specimens. The pelvic flexures of 13 client-owned horses were harvested. Each pelvic flexure had 1 enterotomy performed; 6 were closed via staples, 7 closures were hand-sewn. Luminal diameter at the enterotomy site was assessed via contrast radiography performed pre-and post-enterotomy. Bursting pressure of the closure was assessed by continuous manometry during rapid infusion. Time ...
Morandi L, Sabattini S, Renzi A, Rigillo A, Bettini G, Dervas E, Schauer A, Morandi M, Gissi DB, Tarsitano A, Evangelisti S, Tonon C.Ultra-conserved non-coding elements (UCNEs) are genomic sequences that exhibit > 95% sequence identity between humans, mammals, birds, reptiles, and fish. Recent findings reported their functional role in cancer. The aim of this study was to evaluate the DNA methylation modifications of UNCEs in squamous cell carcinoma (SCC) from different mammal species. Fifty SCCs from 26 humans, 17 cats, 3 dogs, 1 horse, 1 bovine, 1 badger, and 1 porcupine were investigated. Fourteen feline stomatitis and normal samples from 36 healthy human donors, 7 cats, 5 dogs, 5 horses, 2 bovines and 1 badger were c...
Barnés CM, Petoud S, Cohen SM, Raymond KN.The ability of ferritin as an Fe(II) detoxifier and Fe(III) storage protein is limited by its ability to recognize and incorporate Fe(II), which is then oxidized and mineralized at internal protein sites. The Cr(III) amine complex [Cr(N(CH(2)CH(2)NH(2))(3)(H(2)O)(OH)](2+) [abbreviated as Cr(TREN)] is a kinetically inert inhibitor of iron incorporation and mineralization in ferritin. Unlike other inhibitors, Cr(TREN) can only exchange its two aqua/hydroxy ligands. Competition studies between Cr(TREN) and Tb(III) binding have been performed in horse spleen ferritin (HoSF) to probe uptake of Fe(I...
Turner PG, Dugdale A, Young IS, Taylor S.Monitoring the composition of gases breathed by anaesthetised patients requires measurement methods with fast responses, high accuracy and good reliability. There is also an increasing demand for systems to be able to monitor more than one target analyte simultaneously, but some gas analysers can be sensitive to the presence of methane gas in exhaled breath, consequently leading to inaccurate measurements of the anaesthetic agent. This study investigated the feasibility of employing portable quadrupole mass spectrometry to monitor volatile anaesthetic agents (halothane, isoflurane and sevoflur...
Wotman KL, Chow L, Martabano B, Pezzanite LM, Dow S.Ocular surface squamous neoplasia (OSSN) is the major cause of corneal cancer in man and horses worldwide, and the prevalence of OSSN is increasing due to greater UVB exposure globally. Currently, there are no approved treatments for OSSN in either species, and most patients are managed with surgical excision or off-label treatment with locally injected interferon alpha, or topically applied cytotoxic drugs such as mitomycin C. A more broadly effective and readily applied immunotherapy could exert a significant impact on management of OSSN worldwide. We therefore evaluated the effectiveness of...
Hoffseth K, Randall C, Hansma P, Yang HT.In an attempt to study the mechanical behavior of bone under indentation, methods of analyses and experimental validations have been developed, with a selected test material. The test material chosen is from an equine cortical bone. Stress-strain relationships are first obtained from conventional mechanical property tests. A finite element simulation procedure is developed for indentation analyses. The simulation results are experimentally validated by determining (1) the maximum depth of indentation with a single cycle type of reference point indentation, and (2) the profile and depth of the ...
Morreale RJ, Wilkie DA, Gemensky-Metzler AJ, Weisbrode SE, Willis MA.To determine the acute histologic effects of semiconductor diode laser transscleral cyclophotocoagulation (TSCP) on the normal equine eye. Methods: Part 1: eight eyes of four horses. Part 2: 10 eyes of five horses. Methods: Part 1: TSCP was performed on four eyes at 4 mm and four eyes at 6 mm posterior to the limbus with 15 sites treated in four quadrants at 1800 mW for 1500 ms. The globes were sectioned transversely or sagitally to examine all quadrants and histologic sections were taken every 1 mm for the entire globe. Part 2: Based on the results from Part 1, TSCP was performed at 20 sites ...
Ferreira C, Palhares MS, de Melo UP, Chiarini-Garcia H, Maranhão RPA, Gheller VA, Leme FOP.To determine the effect of the inclusion method on the histomorphometric evaluation of the gastrointestinal mucosa of horses, jejunum samples were collected using flank laparotomy. Sixteen mixed breed healthy adult horses, including four males and 12 females, aged 4-14 years with an average body weight of 248.40 ± 2.28 kg, were used. Jejunal biopsies were collected and analyzed by light microscopy using two methods: group 1 comprised biopsies fixed using 10% neutral formalin and embedded in paraffin; biopsies in group 2 were fixed in 2.5% glutaraldehyde in 0.1 M phosphate buffer pH 7.2, follo...
Gronert GA, Fung DL, Jones JH, Shafer SL, Hildebrand SV, Disbrow EA.We investigated the effects of body size on the pharmacokinetics and pharmacodynamics of the renally cleared muscle relaxant metocurine. We hypothesized that pharmacokinetics of the drug would change allometrically in proportion to physiological time [infinity Mb0.25, where Mb is body mass] and that pharmacodynamics would be independent of size because of the highly conserved structure of the acetylcholine receptor. Metocurine effects during general anesthesia were examined in 17 rats, 8 cats, 6 dogs, 5 pigs, 7 sheep, and 12 horses. Allometric analysis demonstrated size dependence for pharmaco...
Tsujimura K, Yamada M, Nagata S, Yamanaka T, Nemoto M, Kondo T, Kurosawa M, Matsumura T.We investigated the pharmacokinetics of penciclovir after oral administration of its prodrug famciclovir to horses. Following an oral dose of famciclovir at 20 mg/kg, maximum plasma concentrations of penciclovir occurred between 0.75 and 1.5 hr (mean 0.94 + or - 0.38 hr) after dosing and were in the range 2.22 to 3.56 microg/ml (mean 2.87 + or - 0.61 microg/ml). The concentrations of penciclovir declined in a biphasic manner after the peak concentration was attained. The mean half-life of the rapid elimination phase was 1.73 + or - 0.34 hr whereas that of the slow elimination phase was 34.34 +...
Lopez-Navarro G, Trigo-Tavera FJ, Rodriguez-Monterde A, Gutierrez-Ospina G, Arechavaleta-Velasco M, Schumacher J, Schumacher J.Proximal suspensory desmitis (PSD) is a common cause of lameness in the pelvic limb, but could also affect the thoracic limb of competing and non-competing horses. Most horses diagnosed with PSD in a thoracic limb respond to rest followed by controlled exercise, but in a small percentage of affected horses, lameness persists. In one study, four horses chronically lame because of PSD in a thoracic limb became sound after neurectomy of the deep branch of the lateral palmar nerve (DBLPaN), which innervates the proximal aspect of the suspensory ligament (SL; Guasco et al., 2013). Whether neurectom...
French DA, Pharr JW, Fretz PB.Diagnostic ultrasonography was used during surgery to assist in the removal of a piece of wire from the retropharyngeal region. A 3-year-old Quarter Horse mare was referred with dysphagia of 2 days' duration. Radiography revealed a 9-cm piece of wire located caudodorsal to the larynx. A ventral surgical approach was performed, dissecting along the right side of the larynx and trachea. The surgical field was filled with 0.85% sterile physiologic saline solution. A 5 MHz-mm sector scanner probe immersed in the fluid was able to locate the wire and facilitate the direction and depth of dissection...
Smits K, Goossens K, Van Soom A, Govaere J, Hoogewijs M, Peelman LJ.In vitro-produced (IVP) equine blastocysts can give rise to successful pregnancies, but their morphology and developmental rate differ from those of in vivo-derived equine blastocysts. The aim of the present study was to evaluate this difference at the genetic level. Suppression subtractive hybridisation (SSH) was used to construct a cDNA library enriched for transcripts preferentially expressed in in vivo-derived equine blastocysts compared with IVP blastocysts. Of the 62 different genes identified in this way, six genes involved in embryonic development (BEX2, FABP3, HSP90AA1, MOBKL3, MCM7 a...
Kydd JH, Butcher GW, Antczak DF, Allen WR.The expression of class I Major Histocompatibility Complex (MHC) molecules by early trophoblast of intraspecific horse and donkey, interspecific mule and extraspecific donkey-in-horse conceptuses was determined using a rat monoclonal antibody (MAC 291) in a peroxidase anti-peroxidase immunohistochemical technique. Most non-invasive allantochorion of horse, donkey and mule conceptuses did not express class I MHC molecules at any stage of gestation except in small isolated patches of pseudostratified trophoblast lying adjacent to the openings of endometrial glands. In contrast, MHC class I molec...
Wong D, Wilkins PA, Bain FT, Brockus C.Neonatal encephalopathy is a common central nervous system disorder of neonatal foals and human infants, resulting in clinical signs such as lethargy, inappropriate behavior, seizures, and other neurologic deficits. Although neonatal encephalopathy is frequently seen in equine practice, a paucity of veterinary clinical and basic science research data is available. Therefore, the pathophysiologic mechanisms of this disorder in equids, such as energy deprivation, excess excitatory amino acids, and free radical injury, have been extrapolated from human medicine. Equine veterinarians have used var...
Wong DM, Alcott CJ, Wang C, Hay-Kraus BL, Buchanan BR, Brockus CW.To evaluate the effects of various flow rates of oxygen administered via 1 or 2 nasal cannulae on the fraction of inspired oxygen concentration (FIO2) and other arterial blood gas variables in healthy neonatal foals. Methods: 9 healthy neonatal (3- to 4-day-old) foals. Methods: In each foal, a nasal cannula was introduced into each naris and passed into the nasopharynx to the level of the medial canthus of each eye; oxygen was administered at 4 flow rates through either 1 or both cannulae (8 treatments/foal). Intratracheal FIO2, intratracheal end-tidal partial pressure of carbon dioxide, and a...
Hardy J, Bertone AL, Muir WW.To determine oxygen metabolism, permeability, and blood flow in isolated joints in response to interleukin 1beta (IL-1beta) and contribution of innervation. Methods: One metacarpophalangeal (MCP) joint of 24 adult horses. Methods: The MCP joint was isolated for 6 hours in a pump-perfused, auto-oxygenated, innervated or denervated preparation. Isolated joints were assigned to the following 4 groups: control, control-denervated, inflamed, and inflamed-denervated, and inflammation was induced by intra-articular injection of IL-1beta. Circuit arterial and venous pressures, flows, and blood gas ten...
Weber JA, Causey RC, Emmans EE.To evaluate the technique of ultrasound-guided luteal injection in mares, PGF2alpha was administered under ultrasound guidance to horse mares (n = 7 to 9 per group) on Day 9 postovulation via either a systemic (i.m.; zero, 0.01, 0.1, or 5 mg/dose) route or a local intraluteal (i.l.; zero, 0.01 or 0.1 mg/dose) route. The luteolytic efficacy of each treatment was determined based on post-treatment decreases in progesterone concentration, interval to uterine edema (IE) and interovulatory interval (IOI). Local administration of PGF2alpha directly into the CL consistently induced luteolysis, at dos...
Niemelä TM, Tulamo RM, Aaltonen K, Sankari SM, Hielm-Björkman AK.Inflammatory and degenerative activity inside the joint can be studied in vivo via analysis of synovial fluid (SF) biomarkers, which are molecular markers of inflammatory processes and tissue turnover. The aim of this study was to investigate the response of selected biomarkers in the SF after an intra-articular (IA) high-molecular-weight non-animal stabilized hyaluronic acid (NASHA) treatment. Our hypothesis was that prostaglandin E (PGE), substance P, aggrecan chondroitin sulfate 846 epitope (CS846), and carboxypeptide of type II collagen (CPII) concentrations in SF would decrease more in th...
Barton MH, Ferguson D, Davis PJ, Moore JN.Pentoxifylline (7.5 mg/kg) was bolused intravenously to eight healthy horses and was immediately followed by infusion (1.5 mg/kg/h) for 3 h. Clinical parameters were recorded and blood samples were collected for 24 h. Plasma was separated and concentrations of pentoxifylline, its reduced metabolite I, and 6-keto-prostaglandin F1 alpha were determined. Heparinized whole blood was also incubated ex vivo with 1 ng Escherichi coli endotoxin/mL blood for 6 h before determination of plasma tumour necrosis factor activity. The peak plasma concentrations of pentoxifylline and metabolite I occurred at ...