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.
Dirikolu L, Hughes C, Harkins D, Boyles J, Bosken J, Lehner F, Troppmann A, McDowell K, Tobin T, Sebastian MM, Harrison L, Crutchfield J, Baskin SI....The epidemiological association between black cherry trees and mare reproductive loss syndrome has focused attention on cyanide and environmental cyanogens. This article describes the toxicokinetics of cyanide in horses and the relationships between blood cyanide concentrations and potentially adverse responses to cyanide. To identify safe and humane blood concentration limits for cyanide experiments, mares were infused with increasing doses (1-12 mg/min) of sodium cyanide for 1 h. Infusion at 12 mg/min produced clinical signs of cyanide toxicity at 38 min; these signs included increased heart...
Park SC, Yun HI.The pharmacokinetic properties of norfloxacin-glycine acetate (NFLXGA) were determined in six horses following a single intravenous (i.v.) and intramuscular (i.m.) dose of 4 mgkg(-1) body weight. Following i.v. and i.m. administration, the plasma drug concentrations were best fitted by an open two-compartment model with a rapid distribution phase. After i.v. NFLXGA administration, the distribution (t(1/2alpha)) and elimination half-life (t(1/2beta)) were 0.42 (0.05) and 5.44 (1.36)h. The volume of distribution of NFLXGA at steady state (Vd(ss)) was 2.19 (0.53) Lkg(-1). After NFLXGA i.m. admini...
Squires EL, Carnevale EM, McCue PM, Bruemmer JE.Recent studies demonstrated that zwitterionic buffers could be used for satisfactory storage of equine embryos at 5 degrees C. The success of freezing embryos is dependent upon size and stage of development. Morulae and blastocysts <300 microm can be slowly cooled or vitrified with acceptable pregnancy rates after transfer. The majority of equine embryos are collected from single ovulating mares, as there is no commercially available product for superovulation in equine. However, pituitary extract, rich in FSH, can be used to increase embryo recovery three- to four-fold. Similar to human medic...
Holcombe SJ, Cornelisse CJ, Berney C, Robinson NE.To determine whether the hyoepiglotticus muscle has respiratory-related electromyographic activity and whether electrical stimulation of this muscle changes the position and conformation of the epiglottis, thereby altering dimensions of the aditus laryngis. Methods: 6 Standardbred horses. Methods: Horses were anesthetized, and a bipolar fine-wire electrode was placed in the hyoepiglotticus muscle of each horse. Endoscopic images of the nasopharynx and larynx were recorded during electrical stimulation of the hyoepiglotticus muscle in standing, unsedated horses. Dorsoventral length and area of ...
Moore-Colyer MJ, Hyslop JJ, Longland AC, Cí·¯ord D.An in sacco mobile bag technique was used to determine the rate and extent of disappearance of unmolassed sugar-beet pulp, soyabean hulls, hay cubes and an oat hull-naked oats mixture (67:33, w/w) in the foregut and total digestive tract of ponies. Ponies were administered naso-gastrically polyester mesh bags containing 350 mg feed, in a Latin square design. Bags were collected at the ileo-caecal junction (small intestine bag, SIB) and in the faeces (faecal bag, FB) and their residues analysed for proximate constituents and NSP composition and content. DM disappearances from individual bags we...
Lees P, Landoni MF.Carprofen is a nonsteroidal anti-inflammatory drug of the 2-arylpropionate subclass. It contains a single chiral centre and exists in two enantiomeric forms. In this study rac-carprofen, at two dosages, 0.7 and 4.0 mg/kg, and placebo were administered i.v. to six New Forest horses in a three period cross-over study. The concentration-time profiles were established for R(-) and S(+)-carprofen for plasma and both inflamed (exudate) and noninflamed (transudate) tissue cage fluids. R(-)-carprofen was the predominant enantiomer in all three fluids, as indicated by plasma area under the curve (AUC) ...
Al-Hizab F, Clegg PD, Thompson CC, Carter SD.To investigate the relationship between matrix metalloproteinase (MMP) activity and osteochondritis dissecans (OCD) in the equine joint. Methods: Equine articular cartilage was obtained from normal (N = 8) and osteochondrotic (OCD) (N = 6) femoropatellar joints from horses at necropsy. The activity of gelatinase MMPs was determined in sections of cartilage by in situ gelatin zymography. Results: Gelatinase activity was markedly increased in articular cartilage obtained from OCD samples and was particularly prominent in the deep cartilage zone. Activity was only seen in the pericellular area of...
Martoriati A, Duchamp G, Gérard N.Paracrine factors have significant effects during folliculogenesis. Because of various morphological features, the mare is a convenient model to study in vivo the effects of factors involved in periovulatory events. In the present work, epidermal growth factor (EGF; experiment 1, n = 49 mares) and interleukin-1beta and interleukin-1RA (IL-1beta and IL-1RA, respectively; experiment 2, n = 80 mares) were injected intrafollicularly to evaluate the influence of these factors on in vivo maturation of equine preovulatory follicles. A transvaginal ultrasound-guided injection was performed when the di...
Laverty S, Okouneff S, Ionescu M, Reiner A, Pidoux I, Webber C, Rossier Y, Billinghurst RC, Poole AR.Articular osteochondrosis (OCD) occurs in both man and animals. The etiology remains to be determined. Studies of OCD lesions in animals may provide clues as to its pathogenesis. The aim of our study was to determine whether there was evidence for increased degradation namely proteoglycan (PG) release and type II collagen cleavage in articular cartilage harvested from OCD lesions. We examined ex vivo explants at post-mortem from equine OCD lesions and macroscopically normal site and age matched cartilage. These were cultured over a 10 day period in serum-free medium. Type II collagen cleavage ...
Sriprapat S, Aeksowan S, Sapsutthipas S, Chotwiwatthanakun C, Suttijitpaisal P, Pratanaphon R, Khow O, Sitprija V, Ratanabanangkoon K.Therapeutic antivenom against snakes was first produced by Albert Calmette in 1894. Since then antivenoms have saved the life of countless snakebite victims. However, there are still many problems associated with antivenom production, for example variable percentage of responder horses, low neutralizing potency of antivenom, the large amount of snake venom needed for immunization and the difficulties encountered in producing potent polyvalent antivenoms. These problems have led to shortage and high cost of antivenom and, in some cases, failure of treatment. In 1997, a new immunization protocol...
Hanzawa K, Lear TL, Piumi F, Bailey E.Consensus DNA sequences from human, mouse and/or rat were used to design oligonucleotide primers for equine homologues of exons 16, 17 and 20-23 of potassium chloride co-transporter (SLC12A4) and exons 10, 11 and 3, 4, respectively, for two amino acid transporters (SLC7A10 and SLC7A9). DNA sequences of the PCR products showed high sequence identity to these regions. Equine BAC clones were obtained for SLC12A4 and SLC7A10 and mapped to equine chromosomes ECA3p13 and ECA10p15, respectively, by fluorescence in situ hybridization (FISH). Several single nucleotide polymorphisms (SNP) were found. Su...
Aurich C, Gerlach T, Aurich JE, Hoppen HO, Lange J, Parvizi N.In the non-breeding season, LH release is reduced via dopaminergic systems in the ram. On the other hand, our previous studies demonstrated an opioidergic inhibition of LH release in stallions outside the breeding season. Thus, in the present study we investigated the dopaminergic regulation of LH and prolactin secretion in stallions, considering interactions between dopamine and opioids. To achieve this, stallions (n=8) were treated with the dopamine antagonist sulpiride (0.6 mg/kg), the opioid antagonist naloxone (0.5 mg/kg), sulpiride plus naloxone or saline in December, March and June. Two...
Thomason JJ, McClinchey HL, Jofriet JC.Finite-element (FE) methods have great potential in equine biomechanics in evaluating mechanical stresses and strains in tissues deep within the hoof. In this study, we critically assessed that potential by comparing results of FE analyses of capsular strain with in vivo data. Nine FE models were developed, corresponding to the shape of hooves for which in vivo principal strain data are available. Each model had the wall, laminar junction, sole and distal phalanx (PIII). In a first loading condition (LC1), force is distributed uniformly to the bearing surface of the wall to determine reaction ...
Hultén C, Grönlund U, Hirvonen J, Tulamo RM, Suominen MM, Marhaug G, Forsberg M.Despite the importance of noninfectious joint diseases in equine medicine, little is known about the acute phase response which may be elicited if the local inflammatory process of noninfectious arthritis is sufficiently strong, Therefore the aim of this study was to monitor the systemic inflammatory response during experimentally-induced noninfectious arthritis by studying the dynamics in serum of the acute phase proteins serum amyloid A (SAA), haptoglobin, fibrinogen and alpha2-globulins. Twenty-four Standardbred horses, age 3-7 years, found healthy on thorough clinical, radiological, haemat...
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...
Lebis C, Bourdeau P, Marzin-Keller F.Allergic diseases are often diagnosed clinically in the horse without performing diagnostic tests. The purpose of this work was to contribute to the validation of intradermal skin tests in the horse. Eighty-three horses, 14 showing skin or respiratory signs of supposed allergic origin, were subjected to an intradermal skin test using 6 different allergens, positive and negative controls. The tests were read for all animals after 20 min, and for 29 horses after 1 and 4 h. Additionally, 19 horses were tested a few months apart. The comparison after 20 min of the cutaneous reactions to allergens ...
Colavizza M, Hervagault JF.After extraction and purification, the kinetic behavior of the Ca(2+)/calmodulin-dependent protein kinase II (CaM kinase II) from horse brain was investigated as a function of ATP and a synthetic substrate, syntide-2. Both phospho- and dephospho- forms of the enzyme obey a bi-bi random mechanism. The K(M)s for ATP (K(M,ATP)) and syntide-2 (K(M,syntide-2)) were determined as equal to 80 and 30 microM, respectively. However, the maximum reaction yield is decreased by 50% when the enzyme is (auto)phosphorylated. In addition, this phosphorylated form of the enzyme leads to the formation of a total...
Carstanjen B, Sulon J, Banga-Mboko H, Beckers JF, Remy B.This study describes for the first time the development and validation of a sensitive and specific radioimmunoassay (RIA) for equine osteocalcin (OC) quantification using purified equine OC as standard, tracer, and immunogen for antibody formation in rabbits. The assay allowed to measure equine serum OC levels with a sensitivity of 0.2 ng/mL. Immunoreactive serum OC values of clinically normal, different-aged horses ranged from 3.68 to 127.31 ng/mL. Intra- and inter-assay coefficients of variation (CV) were 6.2 and 8.2%, respectively. Serial equine serum sample dilutions were linear. The recov...
Perkins GA, Yeager A, Erb HN, Nydam DV, Divers TJ, Bowman JL.The purpose of this study was to determine if colostrum-deprived foals with experimentally induced Rhodococcus equi pneumonia have a decreased severity of the disease and decreased mortality rate when given hyperimmune (HI) R. equi antibody plasma (R. equi titer at least 100 % and virulence-associated protein A [VapA] at least 10000) prophylactically versus when given normal equine plasma (R. equi titer less than 20 % and VapA less than 160). Sixteen colostrum-deprived foals (R. equi titer less than 5 %) each received normal equine plasma in the first 24 hours of life (R. equi titer less than ...
Dirikolu L, Mollett BA, Troppmann A, Woods WE, Bratton C, Cashman CP, Schroedter D, Mayer B, Lehner AF, Karpiesiuk W, Hughes C, Boyles J, Harkins JD....Single doses of one, three, and six actuations (120 micro g albuterol/actuation) and multiple daily doses (six actuations per dose four times daily) for 5 days of aerosol albuterol sulfate were sequentially administered to each of six horses using an equine inhaler device (Torpex, 3M Animal Care Products, St. Paul, MN [corrected] and Boehringer Ingleheim Vetmedica, Inc., St. Joseph, MO [corrected]). A 2-week washout period was allowed between each dose. ELISA testing revealed no evidence of albuterol in urine at 24 hours after any single-dose administration. Results indicated that 48 hours or ...
Koenig JB, Cote N, LaMarre J, Harris WH, Trout DR, Kenney DG, Monteith G.To identify and characterize motilin receptors in equine duodenum, jejunum, cecum, and large colon and to determine whether erythromycin lactobionate competes with porcine motilin for binding to these receptors. Methods: Specimens of various segments of the intestinal tracts of 4 adult horses euthanatized for reasons unrelated to gastrointestinal tract disease. Methods: Cellular membranes were prepared from smooth muscle tissues of the duodenum, jejunum, pelvic flexure, and cecum. Affinity and distribution of motilin binding on membrane preparations were determined by use of 125I-labeled synth...
Schwartz AJ, Wilson DA, Keegan KG, Ganjam VK, Sun Y, Weber KT, Zhang J.To determine significant molecular and cellular factors responsible for differences in second-intention healing in thoracic and metacarpal wounds of horses. Methods: 6 adult mixed-breed horses. Methods: A full-thickness skin wound on the metacarpus and another such wound on the pectoral region were created, photographed, and measured, and tissue was harvested from these sites weekly for 4 weeks. Gene expression of type-I collagen, transforming growth factor (TGF)-beta1, matrix metalloproteinase (MMP)-1, and tissue inhibitor of metalloproteinase (TIMP)-1 were determined by quantitative in situ ...
Jacks S, Giguère S, Gronwall RR, Brown MP, Merritt KA.Clarithromycin offers numerous advantages over erythromycin and thus, is an attractive alternative for the treatment of Rhodococcus equi infections in foals. The disposition of clarithromycin was investigated in 6 foals after intragastric administration at a dose of 10 mg/kg body weight. Detectable serum concentrations of clarithromycin were found in 3 of 6 foals at 10 minutes and in all foals by 20 minutes post-administration. Time to peak serum concentration (Tmax) was 1.5 hours and peak serum concentration (Cmax) was 0.92+/-0.17 microg/ml. Mean serum concentrations decreased to 0.03 microg/...
Hosaka Y, Kirisawa R, Yamamoto E, Ueda H, Iwai H, Takehana K.Although inflammatory activation of cytokines have been analyzed in various tissues, there have only been a few and as-yet-inconclusive studies on cytokines in equine tendons. In this study, the localizations of 4 cytokines (IL-1alpha, IL-1beta, TNFalpha and IFNgamma) in tendinocytes of the equine superficial digital flexor tendon (SDFT) were analyzed by the use of an immunohistochemical method. In inflamed tendons positive staining for all 4 cytokines antibodies were detected in endotedinieum cells and vascular epithelial cells. In contrast, negative or trace immunoreactions were obtained in ...
Giese M, Bahr U, Jakob NJ, Kehm R, Handermann M, Müller H, Vahlenkamp TH, Spiess C, Schneider TH, Schusse G, Darai G.Equine arteritis virus (EAV) is the causative agent of the equine viral arteritis. It is a small RNA virus with a linear, non-segmented plus RNA genome. EAV is a member of the Arteriviridae family that includes porcine reproductive and respiratory syndrome virus (PRSSV), simian haemorrhagic fever virus (SHFV) and lactate dehydrogenase virus (LDV). The viral transmission is via respiratory and reproductive routes. Clinical signs in horses vary, and severe infection can lead to abortions in pregnant mares or neonatal foal death. The aim of this study was to investigate the development of the imm...
Svistunenko DA, Dunne J, Fryer M, Nicholls P, Reeder BJ, Wilson MT, Bigotti MG, Cutruzzolà F, Cooper CE.The reactions of hydrogen peroxide with human methemoglobin, sperm whale metmyoglobin, and horse heart metmyoglobin were studied by electron paramagnetic resonance (EPR) spectroscopy at 10 K and room temperature. The singlet EPR signal, one of the three signals seen in these systems at 10 K, is characterized by a poorly resolved, but still detectable, hyperfine structure that can be used to assign it to a tyrosyl radical. The singlet is detectable as a quintet at room temperature in methemoglobin with identical spectral features to those of the well characterized tyrosyl radical in photosystem...
Kingston JK, Bayly WM, Meyers KM, Sellon DC, Wardrop KJ.There is evidence that equine platelet reactivity is altered by strenuous exercise. Changes in platelet reactivity could impact haemostasis following exercise-induced injury and may play a role in the pathophysiology of exercise-induced pulmonary haemorrhage. Interpretation of results of previous studies is hindered by potential in vitro-induced changes in platelet activity through the choice of anticoagulant and the use of platelet inhibitors. The present study was undertaken to re-evaluate the effect of exercise on equine platelets using methodologies that minimise in vitro-induced changes i...
Birch HL, Smith TJ, Poulton C, Peiffer D, Goodship AE.Partial rupture occurs most often to the superficial digital flexor tendon (SDFT) of the forelimb at the mid-metacarpal level. In this study, we tested the hypothesis that the mid-metacarpal region of the SDFT has the smallest cross sectional area (CSA) and a similar collagen content to other regions and, therefore, represents a weak point in the tendon. The SDFT was collected from the forelimbs of 9 horses. Each tendon was marked at 7 different levels from the origin of the accessory ligament to the phalangeal region. The CSA, water content and collagen content was measured at each level. The...
Koho NM, Väihkönen LK, Pösö AR.The lactate transport activity of red blood cells (RBC) varies widely among different species; in equine RBC, the activity of the main lactate carrier, H+-monocarboxylate co-transporter (MCT), is distributed bimodally. The influence of lactate transport activity is measurable in vivo; after maximal exercise, the RBC lactate concentration in horses with high (HT) lactate transport activity is higher than in those with low (LT) activity. To study the expression of MCT in HT and LT horses, blood samples were taken from 10 horses at rest and after submaximal exercise. Blood and plasma lactate conc...
Bonelli F, Laus F, Briganti A, Evangelista F, Bazzano M, Conte G, Sgorbini M.There has been increasing interest in blood gas analysis in donkeys. "Point-of-care (POC) testing" is a diagnostic testing performed on or immediately next to the patient. This study assesses the agreement between two POC blood gas analyzers in donkeys. Arterial and venous blood samples were collected from 17 donkeys and analyzed using a fully automated blood gas analyzer (ABL 700 Series Radiometer, Denmark) (RAD) and two POC blood gas analyzers (i-STAT System; VetStat, Idexx). The parameters revealed by all three devices were submitted to a canonical discriminant analysis, to evaluate which p...
Canisso IF, Loux S, Scoggin KE, Squires EL, Troedsson MH, Ball BA.Characterisation of fetal fluids in healthy and disease states of pregnant mares can help to unravel the pathophysiology and to identify putative markers of disease. Thus, this study aimed to compare the protein composition of: (1) amniotic and allantoic fluids of healthy mares obtained immediately after euthanasia and (2) allantoic fluid harvested via centesis before and after experimental induction of placentitis via transcervical inoculation of Streptococcus equi ssp zooepidemicus in healthy mares. Fetal fluids were analysed with a high-throughput proteomic technique after in-gel digestion....
Wilson WD, Spensley MS, Baggot JD, Hietala SK.The pharmacokinetics and bioavailability of rifampin were determined after IV (10 mg/kg of body weight) and intragastric (20 mg/kg of body weight) administration to 6 healthy, adult horses. After IV administration, the disposition kinetics of rifampin were best described by a 2-compartment open model. A rapid distribution phase was followed by a slower elimination phase, with a half-life (t1/2[beta]) of 7.27 +/- 1.11 hours. The mean body clearance was 1.49 +/- 0.41 ml/min.kg, and the mean volume of distribution was 932 +/- 292 ml/kg, indicating that rifampin was widely distributed in the body....
Badial PR, Oliveira-Filho JP, Pantoja JC, Moreira JC, Conceição LG, Borges AS.Hereditary equine regional dermal asthenia (HERDA) is an autosomal recessive disorder affecting quarter horses (QHs); affected horses exhibit characteristic skin abnormalities related to abnormal collagen biosynthesis. Objective: To characterize the thickness and morphological abnormalities of the skin of HERDA-affected horses and to determine the interobserver agreement and the diagnostic accuracy of histopathological examination of skin biopsies from horses with HERDA. Methods: Six affected QHs, confirmed by DNA testing, from a research herd and five unaffected QHs from a stud farm. Methods:...
AbouLaila M, Allam T, Roshdey T, Elkhatam A.Strongylus vulgaris has high pathogenicity to equines. It causes aneurysm and thrombosis in the arteries particularly an anterior mesenteric artery, that is fatal to equines. In this study, we aimed to diagnose microscopically the natural infection of donkeys with Strongylus vulgaris from Sadat City, Minoufiya Governorate, Egypt. Fecal egg culture was used after the diagnosis of strongyle eggs to identify the species. Hematological and biochemical parameters were assessed. Adult worms were collected after post mortem examination of the infected animal. The sequence of ITS-2 was used to confirm...
Riggs LM, Krunkosky TM, Noschka E, Boozer LA, Moore JN, Robertson TP, Peroni JF.To compare characteristics and enzymatic products of leukocytes detected in the skin and laminar tissues of horses administered black walnut heartwood extract (BWHE) and horses administered purified lipopolysaccharide (LPS). Methods: 25 healthy 5- to 15-year-old horses. Methods: Horses were randomly assigned to receive LPS (20 ng of O55:B5 Escherichia coli endotoxin/kg; n = 5) IV or 6 L of BWHE (10) or water (control group; 10) via nasogastric intubation. Horses were euthanatized 12 hours after treatment or at onset of Obel grade 1 lameness. Laminar tissue samples and skin samples from the mid...
Wardle EN.Assessment of changes in activity of the reticuloendothelial system (RES), including the mesangial cells of the kidney, has been made by means of clearance studies of human aggregated gamma-globulin and of colloidal gold, during the course of horse serum sickness nephritis. RES blockade was found after protein loading and at the phase of circulating immune complexes. At other times RES activity was normal or increased. “Mesangial saturation” may have important implications for human nephritis.
Atkins CA, Pond KR, Madsen CK, Moorman VJ, Roman-Muniz IN, Archibeque SL, Grandin T.The objective of the control study was to assess 2 prominent fluctuations in a single optical signal as being either a true first hoof contact or a last break-over based on descriptive measures. The study builds on initial findings from a preliminary investigation of the embedded-optical-base system's (EOBS) capabilities in signal capturing and feasibility as potential alternative to existing gait technologies, such as piezoelectric (e.g., load cell) systems. Hoof contacts and break-overs were measured (0 to 1 au; arbitrary units) using a 2.4-m (length) × 0.9-m (width) platform containing 1 E...
Choi YH, Gibbons JR, Canesin HS, Hinrichs K.Prospective studies were conducted to help define procedural factors affecting in vitro embryo production via intracytoplasmic sperm injection (ICSI) of equine oocytes. In experiment 1, use of 10% fetal bovine serum as a protein source in embryo culture medium resulted in a higher blastocyst rate than did use of a combination of 3% fetal bovine serum, 3% equine preovulatory follicular fluid, and 4% human serum substitute (37% vs. 15%, respectively, P < 0.05). In experiment 2, the effect of zinc supplementation (0, 0.5, 1, or 1.5 μg/mL) during IVM was examined. There were no significant di...
Kirschvink N, Bureau F, Art T, Lekeux P.The 8-epi-PGF2alpha is a marker of oxidative stress which is increased in lungs of asthmatic humans and heaves-susceptible horses. 8-Epi-PGF2alpha has also been demonstrated to be an in vitro and in vivo bronchoconstrictor in humans and rodents. We hypothesised that inhaled 8-epi-PGF2alpha was a bronchoconstrictor in healthy and heaves-susceptible horses in clinical remission. The effect on ventilatory mechanics of nebulised 8-epi-PGF2alpha was compared to that of PGF2alpha and U46619, a thromboxane A2 agonist. Pulmonary resistance (R(L)) and dynamic compliance (Cdyn) were assessed in six heal...
Liu X, Zhang Y, Pu Y, Ma Y, Jiang L.Transposable elements (TEs) are diverse, abundant, and complicated in genomes. They not only can drive the genome evolution process but can also act as special resources for adaptation. However, little is known about the evolutionary processes that shaped horses. In this work, 126 horse assemblages involved in most horse breeds in China were used to investigate the patterns of TE variation for the first time. By using RepeatMasker and melt software, we found that the horse-specific short interspersed repetitive elements family, equine repetitive elements (ERE1), exhibited polymorphisms in hors...
Petrova V, Vachkova E.Adipose tissue is recognized as the major endocrine organ, potentially acting as a source of mesenchymal stem cells for various applications in regenerative medicine. Athletic horses are often exposed to traumatic injuries, resulting in severe financial losses. The development of adipose-derived stem cells' regenerative potential depends on many factors. The extraction of stem cells from subcutaneous adipose tissue is non-invasive, non-traumatic, cheaper, and safer than other sources. Since there is a lack of unique standards for identification, the isolated cells and applied differentiation p...
Fontenot RL, Langston VC, Zimmerman JA, Wills RW, Sloan PB, Mochal-King CA.To determine meropenem concentrations in radiocarpal (RC) joint fluid and plasma after intravenous regional limb perfusion (IVRLP). Methods: In vivo experimental study. Methods: Nine healthy adult mares. Methods: Meropenem (500 mg) was injected in the forelimb of standing sedated horses via IVRLP with a pneumatic tourniquet inflated to 400 mmHg. Synovial fluid was collected from RC joints at 0, 0.5, 1, 2, 4, 6, 8, 12, and 18 hours after meropenem injection. Blood samples were collected from the jugular vein at the same time points and at 5 and 15 minutes following injection. Meropenem concentr...
Austin SM, DiPietro JA, Foreman JH, Baker GJ, Todd KS.Sixteen helminth-free pony foals were inoculated with a mean (+/- SD) 2,000 (+/- 545.5) infective Parascaris equorum eggs (day 0). Foals were allocated to replicates of 4, and treatments within each replicate were assigned at random. Treatment administered on postinoculation day (PID) 28 included no treatment (control), 0.2 mg of ivermectin/kg of body weight, 10 mg of oxibendazole/kg, or 6.6 mg of pyrantel base (pamoate)/kg. Paste formulations of the anthelmintics were administered orally. The foals were euthanatized 14 days after treatment (PID 42) and examined for P equorum larvae in the sma...
López-Sanromán FJ, Cruz JM, Santos M, Mazzini RA, Tabanera A, Tendillo FJ.To evaluate the local analgesic effect of ketamine in a palmar digital nerve block at the base of the proximal sesamoid (abaxial sesamoid block) in horses. Methods: 36 mature healthy Andalusian horses. Methods: Horses were randomly assigned to 4 groups of 9 horses each and received an abaxial sesamoid block in a randomly chosen forelimb with 1 of the following: saline (0.9% NaCl) solution, 1% ketamine solution, 2% ketamine solution, or 3% ketamine solution. To determine analgesia, the radiant heat lamp-hoof withdrawal model was used as a noxious thermal stimulus. Before each nerve block, basel...
Tulleners E, Mann P, Raker CW.Epiglottic augmentation with injectable bovine collagen or an autogenous or allogenous auricular cartilage graft was performed in 12 horses with endoscopically and radiographically normal epiglottises. The grafting procedures were easy to perform and did not cause apparent discomfort. Cartilage graft extrusion or resorption may have occurred, but was not seen by endoscopy and lateral laryngeal radiography. Only collagen implants remained evident endoscopically, as smooth round submucosal bulges ventral to the epiglottic cartilage. Two horses with collagen implants, and all horses with cartilag...
Kreider JL, Ogg WL, Turner JW.Six mature stallions were used to test the effect of prostaglandin F2 alpha (PGF2 alpha ) on sperm production and seminal characteristics. Semen was collected from each stallion twice weekly 1 hr following a 10 mg intramuscular injection of PGF2 alpha or a sham injection. A switchback design was used so that three stallions received PGF2 alpha and three served as controls during the first 9 weeks (period 1). Treatment regimens were reversed during the second 9 weeks (period 2). Treatment of stallions with PGF2 alpha resulted in an increase (P less than .05) in gel free seminal volume and a dec...
Beg MA, Gastal EL, Gastal MO, Ji S, Wiltbank MC, Ginther OJ.Transvaginal ultrasound-guided luteal biopsy was used to evaluate the effects of prostaglandin (PG)F2alpha on steady-state concentrations of mRNA for specific genes that may be involved in regression of the corpus luteum (CL). Eight days after ovulation (Hour 0), mares (n=8/group) were randomized into three groups: control (no treatment or biopsy), saline+biopsy (saline treatment at Hour 0 and luteal biopsy at Hour 12), or PGF2alpha+biopsy (5mg PGF2alpha at Hour 0 and luteal biopsy at Hour 12). The effects of biopsy on CL were compared between the controls (no biopsy) and saline+biopsy group. ...
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...
Leisinger CA, Klein C, Markle ML, Premanandan C, Sones JL, Pinto CRF, Paccamonti DL.Aluteal cycles were induced in the mare to evaluate the effects of progesterone deprivation on the gene expression of embryos and endometrium collected eight days after ovulation. We hypothesized that the transcript expression would be altered during induced aluteal (AL) cycles (low progesterone <1 ng/mL) when compared with control cycles during diestrus (high progesterone; > 4 ng/mL) for 1) the embryonic expression of progesterone-mediated transcripts and those related to normal embryo growth and development and 2) the endometrial expression of progesterone-mediated transcripts and those ...
Squires EL.Equine oocytes obtained either by transvaginal ultrasound-guided follicular aspiration or from slaughterhouse ovaries can be matured in vitro. This generally requires culture in TCM-199 containing serum and hormones for 30 to 36 hours. With this protocol, approximately 50% to 60% of the oocytes are at metaphase-II at the end of the culture period. At least some of these oocytes appear viable based on production of fertilized eggs either through in vitro fertilization or fertilization in vivo of a recipient mare. The success of producing equine embryos in vitro is still extremely low. More than...
Ramery E, Fievez L, Fraipont A, Bureau F, Lekeux P.The long pentraxin 3 (PTX3) plays an important role in host defence and its over-expression may contribute to airway injury. The aim of the present study was therefore to characterize in more detail PTX3 and its expression in the horses' airway. Six healthy horses and six horses affected by recurrent airway obstruction (R.A.O.) were submitted to a dusty environment challenge. PTX3 DNA and cDNA were cloned and sequenced. PTX3 expression was evaluated by RT-qPCR, Western blotting and immunohistochemistry in bronchoalveolar lavage fluid (BALF) cells, BALF supernatant and bronchial epithelial cell...
Haase F, Siewert C, von Rautenfeld DB, Fischbach JU, Seifert H.Measuring the leg volume of horses is useful for diagnostic and treatment of different diseases in relation to swollen legs. In the present study different methods to quantify the limb volume are compared, the water displacement method, an optoelectronic 2-dimensional body scanner, the so-called perometer and calculation of volume by applying the disc model. As reference method the golden standard of human medicine - the water displacement method was used. We took volume measurements from different tall horses in a defined section of the forelegs between the coronary band and the carpal joint....
Souza SS, Aguiar FLN, Alves BG, Alves KA, Brandão FAS, Brito DCC, Raposo RDS, Gastal MO, Rodrigues APR, Figueiredo JR, Teixeira DÍA, Gastal EL.Ovarian tissue transplantation methods using cooled and cryopreserved samples have been attractive options for fertility preservation in animal models and humans. The aim of this study was to evaluate the impact of previous exposure to cooling, cryopreservation, and VEGF on the overall efficiency of equine ovarian tissue after heterotopic xenotransplantation in mice. The end points evaluated were follicular morphology and development, follicular and stromal cell densities, angiogenesis (i.e. the density of new and mature blood vessels), collagen types I and III fiber densities, and total fibro...
Kilcoyne I, Dechant JE, Nieto JE.The objective of the article is to determine the synovial fluid concentrations of amikacin sulfate (AS) after performing an intravenous regional limb perfusion (IVRLP) with the tourniquet in place for 10 minutes and compare this with 30 minutes. This is a randomised crossover experimental design. Animals were seven healthy adult horses. Horses underwent two IVRLP procedures in a randomised, crossover design. The horses received IVRLP with 2 g AS diluted to 60 ml using 0.9% saline in the cephalic vein of alternate limbs with the tourniquet in place for either 10 or 30 minutes, with a ...
Tkachenko AG, Winston GW.Preincubation of horse liver alcohol dehydrogenase (HLADH) with the oxidative agent, tert-butyl hydroperoxide (tBOOH) results in a twofold stimulation of the ethanol dehydrogenase activity of this enzyme. This stimulation was dependent on tBOOH concentration up to 100 mM; above this concentration tBOOH did not further stimulate ethanol oxidation by HLADH. Active-site-directed reagents and classical ADH binary complexes were used to probe the possible mechanism of this activating effect. The rate and extent of stimulation by tBOOH is strongly reduced by binary complexes with NAD(+) or NADH, who...
Briant C, Ottogalli M, Morel M, Guillaume D.The GnRH antagonist antarelix (Teverelix) was administered to mares (0.01 mg/kg, i.v., twice a day) during the periovulatory period. In Experiment 1, 20 mares were divided into a treated (A3d-) and a control (Control-) group. A3d- mares received antarelix for 3 days from the day when the dominant follicle (F1) reached 32 mm (D0). In Experiment 2, 10 mares were divided into a treated (A6d+) and a control (Control+) group. A6d+ mares received antarelix for 6 days from D0 and hCG was injected in all animals (1600 IU, i.v.) on D1. Pregnancies were determined 13 days after ovulation. In both experi...
Moore RM, Muir WW, Bertone AL, Oliver JL.To determine the effect of platelet-activating factor (PAF) antagonist L-691,880 on low-flow ischemia and reperfusion (I-R) of the large colon in horses. Methods: 12 adult horses. Methods: Horses were anesthetized, and the large colon was exteriorized through a ventral median celiotomy and instrumented. Colonic arterial blood flow was reduced to 20% of baseline (BL) and maintained for 3 hours; flow was then restored, and the colon was reperfused for 3 hours. One of two solutions was administered intravenously 30 minutes before reperfusion: group 1, 10 mL/kg 0.9% NaCl; and group 2, 5 mg/kg PAF ...
Kuhnert-Paul Y, Schmäschke R, Daugschies A.Results of parasitological examination of faecal aliquots may vary between diagnostic laboratories. To examine whether inhomogeneous distribution of worm eggs in faecal samples is responsible for this observation, horse faeces provided for routine diagnosis of helminth infection were examined. Distribution of worm eggs was assessed by examining aliquots taken from different locations of the faecal sample by a combined sedimentation-flotation method (KSFV). In addition, it was tested, whether the homogenization of a larger amount (minimum of 40 g) of faeces before performing KSFV improved repro...
Francisco I, Sánchez JA, Cortiñas FJ, Francisco R, Mochales E, Arias M, Mula P, Suárez JL, Morrondo P, Díez-Baños P, Sánchez-Andrade R....The aim of this study was to assess, by a clinical trial, the efficacy of an ivermectin-based pour-on treatment against gastrointestinal parasitic nematodes in naturally infected horses using 2 groups of mature indigenous Pura Raza Galega grazing mares. Faecal and blood samples were collected individually over a 21 week period. Faeces were analysed by the coprological flotation, sedimentation and migration techniques. Changes in circulating blood cells were monitored over the study period. The administration of the ivermectin suppressed the egg-elimination of ascarids and pinworms throughout t...
