Equine health encompasses the study and management of diseases, disorders, and overall well-being of horses. It involves understanding various physiological systems, preventive care, and treatment strategies to maintain optimal health in equine populations. Common areas of focus include nutrition, infectious diseases, orthopedic conditions, and reproductive health. Research in equine health aims to advance knowledge on diagnostic methods, therapeutic interventions, and management practices that improve horse welfare and performance. This page collects peer-reviewed research studies and scholarly articles that explore the diverse aspects of equine health, offering insights into current findings and advancements in the field.
Patton KM, Peek SF, Valentine BA.A 17-year-old Quarter horse mare was referred to Cornell University for postmortem examination after 72 hours of encephalopathy that consisted of depression, mania, and blindness. A plasma sample and cerebral spinal fluid demonstrated hyperammonemia. Gross necropsy examination findings included the following: mild icterus, a transmural mass in the glandular portion of the gastric fundus, multiple masses throughout the liver, and a large tumor thrombus in the portal vein. Microscopically, the gastric mass, hepatic masses, and portal vein thrombus were composed of similar neoplastic epithelial c...
Brandon CI, Vandenplas M, Dookwah H, Murray TF.The aim of this study was to establish a heterologous expression system for the equine adenosine A(3) receptor (eA(3)-R) in an effort to ascertain its pharmacologic profile. Initially, radioligand binding assays identified clones expressing the eA(3)-R in human embryonic kidney cells (HEK) based on the specific binding of [(125)I]AB-MECA. Subsequently, adenylate cyclase assays were utilized to demonstrate functional coupling of the eA(3)-R to the G-protein/adenylate cyclase system. Equilibrium competition binding assays were then performed using selective and non-selective A(3) agonists and an...
Sledge DG, Miller DL, Styer EL, Hydrick HA, Baldwin CA.Granulomatous dermatitis in horses has been linked to many etiologies, including various parasites, fungi, and bacteria. Idiopathic forms of granulomatous inflammation-producing diseases, some of which are localized to the skin, also have been reported in horses. Herein we describe a case of recurrent equine granulomatous skin disease characterized by intranuclear viral inclusions within macrophages and giant cells. The histologic changes were primarily noted in the deep dermis and included multifocal to coalescing areas of necrosis marked by histiocytic cell infiltration and presence of giant...
Saito S, Sawai K, Minamihashi A, Ugai H, Murata T, Yokoyama KK.We describe here the isolation and maintenance of pluripotent embryonic stem (ES) cells from equine blastocysts that have been frozen and thawed. Equine ES cells appear to maintain a normal diploid karyotype in culture. These cells express markers that are characteristic of mouse ES cells, namely, alkaline phosphatase, stage-specific-embryonic antigen 1, STAT3, and Oct4. We also describe protocols for the induction of differentiation in vitro to neural precursor cells in the presence of basic fibroblast growth factor (bFGF), epidermal growth factor, and platelet-derived growth factor and to he...
Brandon CI, Vandenplas M, Dookwah H, Linden J, Murray TF.The aim of the current study was to clone the equine adenosine A(2A) receptor gene and to establish a heterologous expression system to ascertain its pharmacologic profile via radioligand binding and functional assays. An eA(2A)-R expression construct was generated by ligation of the eA(2A) cDNA into the pcDNA3.1 expression vector, and stably transfected into human embryonic kidney cells (HEK). Binding assays identified those clones expressing the eA(2A)-R, and equilibrium saturation isotherm experiments were utilized to determine dissociation constants (K(D)), and receptor densities (B(max)) ...
Serena A, Joiner KS, Schumacher J.Hemangiopericytoma (HP) is a well-recognized neoplasm arising from vascular pericytes that has been reported only in the dog and man. In this study, we describe a 14-year-old female Arabian horse that was presented for surgical excision of a 2-cm-diameter expansile subcuticular mass in the right lower eyelid. Histologically, the mass consisted of loosely arranged interlacing streams and storiform bundles of spindle cells that often formed distinct whorls around a central capillary and bundles of collagen (Antoni A-like pattern). Immunohistochemical analysis revealed strong diffuse cytoplasmic ...
Paciello O, Pasolini MP, Navas L, Russo V, Papparella S.Central core disease is a nonprogressive or slowly progressive congenital myopathy with a variable degree of hypotonia and axial and proximal muscle weakness that is histologically characterized by areas devoid of oxidative enzyme activity, resulting from an absence or low numbers of mitochondria in these regions (central core). A 10-month-old, male, pony foal was examined because of stiff gait, marked contractures of the distal portion of the limbs, flexion deformities of the hooves, and moderate hypotonia that had been present from birth. The foal had increased creatine kinase (282 U/liter; ...
Stadejek T, Mittelholzer Ch, Oleksiewicz MB, Paweska J, Belák S.Equine arteritis virus (EAV) was detected by RT-nested PCR in semen samples from a naturally infected South African donkey. Sequence analysis of the amplified ORF5 fragment revealed only 60 to 70% nucleotide identity to a panel of EAV reference sequences. The unique donkey EAV sequence was also found to be stable during passage in horses. The sequence data reported in this study indicate that the South African donkey variant might represent a new genotype of EAV. The distinct genetic properties of the South African asinine strain of EAV suggest a divergent evolution of this arterivirus in vari...
Galuppo LD, Simpson EL, Greenman SL, Dowd JP, Ferraro GL, Meagher DM.To report clinical evaluation of headless compression screws for repair of metacarpal/metatarsal (MC/MT3) condylar fractures in horses. Methods: Retrospective case study. Methods: Racing Thoroughbreds (n=16) with nondisplaced lateral condylar fractures of MC/MT 3. Methods: Medical records (1999-2004) of horses with nondisplaced longitudinal fractures of the lateral condyle of MC/MT3 were reviewed. Pre-operative variables retrieved were: patient age, gender, limb involvement, injury occurrence, fracture length, and width, evidence of palmar comminution and degenerative joint disease, number of ...
Epstein KL, Parente EJ.To report a laparoscopic technique for insertion of polypropylene mesh in the nephrosplenic space in horses and evaluate outcome. Methods: Descriptive experimental study. Methods: Five healthy mature horses. Methods: One laparoscope and 2 instrument portals were made on the left side of the horse. The nephrosplenic space was measured and appropriately sized polypropylene mesh was inserted and attached to the dorsolateral splenic capsule and perirenal fascia using helical titanium coils. All horses had repeat laparoscopy 4 weeks later and were necropsied at intervals 4-14 weeks after mesh place...
Hornyák A, Bakonyi T, Kulik M, Kecskeméti S, Rusvai M.The occurrence of two important pathogens, equine herpesvirus 1 (EHV1) and equine arteritis virus (EAV) causing abortions, perinatal foal mortality and respiratory disease, was investigated by polymerase chain reaction (PCR) and virus isolation to demonstrate the presence of abortigenic viruses in samples from 248 horse fetuses in Hungary. We found 26 EHV1- and 4 EAV-positive aborted or prematurely born foals from 16 and 4 outbreaks, respectively, proving that despite the widely applied vaccination, EHV1 is a far more important cause of abortions in the studs than EAV. We compared the virus co...
Popot MA, Donval A, Bonnaire Y, Huau J.Feces are a possible medium to be used for horse doping control. Efficient methods for detecting drugs in feces collected from various animals are routinely applied in institutes of food safety in Belgium. We have already tested whether they are applicable to horse feces. In this report, accelerated solvent extraction (ASE), an efficient method for extracting compounds from solid material, has been tested. ASE has been used to replace the diethyl ether liquid-liquid extraction step present in the method initially set up. This technique has been optimized for detecting several non-steroidal ant...
Laan TT, Bull S, van Nieuwstadt RA, Fink-Gremmels J.Beta-agonists have been shown to display anti-inflammatory properties in several experimental models. The aim of this study was to investigate the anti-inflammatory properties of clenbuterol (CB), administered either intravenously or by aerosol, in comparison with fluticasone propionate (FP) in recurrent airway obstruction (RAO)-susceptible horses. Eight horses, of which five were known to be susceptible to RAO, underwent an inhalation challenge with Aspergillus fumigatus (AF) antigen and were treated with CB intravenously, CB by aerosol, or FP by aerosol. Twenty-four hours after the challenge...
Rezaian M.Histology of the tongue, including apex, root and body, in four adult Caspian miniature horses was examined. Serial sections with 6 mum thickness were stained with haematoxylin-eosin and Masson trichrome and studied under light microscope. The tongue was covered by stratified squamous epithelium. It was thick and keratinized bearing numerous lingual papillae on the dorsum, mostly filiform with a very fine keratinized thread projecting above the surface and bending backward. The fungiform papillae were sparsely scattered among the filiform papillae and covered with keratinized squamous epitheli...
Evans KE, McGreevy PD.There is a lack of an established method for quantifying equine skull morphology. This study proposes a method that is valid for use on both live and deceased horses. A total of nine head measurements (skull length, cranial length, nasal length, ratio of cranial:nasal length, cranial width, zygomatic width, mandibular depth, nasal profile area, cranial profile area) and six indices (skull index, cranial index, nasal index, mandibular index, nasal profile index, cranial profile index) were recorded from 30 horses from a variety of breeds whilst the soft tissues of the head were intact. A line w...
Ugryumova N, Gangnus SV, Matcher SJ.Polarization optical coherence tomography (PSOCT) is a powerful technique to nondestructively map the retardance and fast-axis orientation of birefringent biological tissues. Previous studies have concentrated on the case where the optic axis lies on the plane of the surface. We describe a method to determine the polar angle of the optic axis of a uniaxial birefringent tissue by making PSOCT measurements with a number of incident illumination directions. The method is validated on equine flexor tendon, yielding a variability of 4% for the true birefringence and 3% for the polar angle. We use t...
Nielsen MK, Kaplan RM, Thamsborg SM, Monrad J, Olsen SN.Development of resistance to anthelmintic drugs by horse strongyles constitutes a growing threat to equine health because it is unknown when new drug classes can be expected on the market. Consequently, parasite control strategies should attempt to maintain drug efficacy for as long as possible. The proportion of a parasite population that is not exposed to anthelmintic treatment is described as being "in refugia" and although many factors affect the rate at which resistance develops, levels of refugia are considered the most important as these parasites are not selected by treatment and so pr...
Samper JC, Tibary A.Bacterial, viral and protozoal infections may cause severe reproductive losses. The present paper reviews the risk factors, clinical signs and preventive measures for the most important venereal or potential sexually transmitted diseases in horses. The stallion and use of semen for artificial insemination represent major risk factors for the transmission of bacterial contaminants of the penis, including Streptococcus equi subspecies zooepidemicus, Pseudomonas aeruginosa and Klebsiella pneumoniae, known to cause endometritis and infertility in the mare. The role of the stallion in disease trans...
Butcher MT, Bertram JE, Benzuidenhout AJ.The distal forelimb of the horse has a complex array of ligaments that play a critical role in determining function of the digit and are often associated with the initiation of foot pathologies. The collateral ligaments of the distal sesamoid bone (CLDS) play an important role in digit stabilization near the end of foot contact and there is also limited evidence to suggest that the CLDS stabilize the proximal interphalangeal joint (PIPJ) during weight bearing. By virtue of their anatomical attachments where the ligaments pass dorsal to the axis of rotation of the PIPJ, it is reasonable to assu...
Valentine BA, Taylor GH, Stone JK, Halse RR.Forty-four nodular and noninvasive cutaneous fungal granulomas were identified in 34 horses over a 14.5-year period. Cutaneous fungal granulomas were most common in young horses (mean age 6.1 +/- 4.2 years; range 1-19 years). There was no apparent breed or sex bias. Granulomas were either single or multiple, and most often occurred in the skin of the head and neck. The characteristic histological finding was a nodular dermal mass with a mean diameter of 7.3 mm (range 2.5-20 mm) and an intact overlying epithelium. Lesions most often exhibited intense lymphocytic inflammation, with admixed pyogr...
Nogueira SA, Torres SM, Malone ED, Diaz SF, Jessen C, Gilbert S.Imiquimod is an immune response modifier with potent antiviral and antitumour activity. The objective of this pilot study was to evaluate the efficacy of an imiquimod 5% cream (Aldaratrade mark: 3M, Saint Paul, MN, USA) as a topical treatment for equine sarcoids. Fifteen horses with a total of 19 tumours were enrolled, including mixed (7), fibroblastic (5), flat (3), verrucous (2), and nodular (2) types. Baseline data included history, physical examination, tumour location, measurement and digital photography. Imiquimod was applied by the owners three times a week until complete resolution of ...
Frisbie DD, Morisset S, Ho CP, Rodkey WG, Steadman JR, McIlwraith CW.Microfracture of full-thickness articular defects has been shown to significantly enhance the amount of repair tissue. However, there is a suggestion that leaving calcified cartilage inhibits this repair response. Objective: Removal of the calcified cartilage with retention of subchondral bone enhances the amount of attachment of the repair tissue compared with retention of the calcified cartilage layer. Methods: Controlled laboratory study. Methods: There were 1-cm(2) articular cartilage defects made in 12 skeletally mature horses on the axial weightbearing portion of both medial femoral cond...
Sherman RA, Morrison S, Ng D.Hoof disease and injuries are common and serious problems for equines. Maggot debridement therapy (MDT) has been used to treat problematic wounds in humans, but has been used only rarely in other animals. US veterinarians who had employed MDT were surveyed to investigate their reasons for the choice of this treatment and their clinical experiences with it. Between 1997 and 2003, 13 horses were treated by eight veterinarians who used MDT to control infection or debride wounds, which could not easily be reached surgically or were not responding to conventional therapy. Seven animals were lame, a...
Hurtgen JP.Inflammatory conditions of the uterus, collectively known as endometritis, can be classified as acute, chronic, active, or subclinical. This condition causes substantial reductions in mare fertility. To diagnose and treat mares with endometrial inflammation, it is imperative to identify predisposing factors and challenges to the reproductive tract of the mare in a chronological order; these factors change from those of the young maiden filly to the older, multiparous broodmare. This paper addresses predisposing factors, diagnostic procedures and therapy strategies for different mare groups.
Songsermsakul P, Sontag G, Cichna-Markl M, Zentek J, Razzazi-Fazeli E.The paper describes a method for the sensitive and selective determination of zearalenone and its metabolites in urine, plasma and faeces of horses by high performance liquid chromatography and atmospheric pressure chemical ionisation (APCI) mass spectrometry (MS). While only one step sample clean-up by an immunoaffinity column (IAC) was sufficient for plasma samples, urine and faeces samples had to be prepared by a combination of a solid-phase extraction (SPE) and an immunoaffinity column. The method allows the simultaneous determination of zearalenone and all of its metabolites; alpha-zearal...
Sayasith K, Bouchard N, Doré M, Sirois J.The progressive rise in gonadotropins prior to ovulation triggers a marked increase in intrafollicular levels of prostaglandin F(2alpha)(PGF(2alpha)), which is known to interact with PGF(2alpha) receptor (FP). Little is known about the regulation of FP during ovulation. This study was undertaken to characterize the equine FP and its gonadotropin-dependent regulation in preovulatory follicles prior to ovulation. The full-length equine FP encodes a 366-amino acid protein that is 82-93% homologous to other species. Using semi-quantitative RT-PCR/Southern blot, we showed that FP mRNA expression wa...
Momozawa Y, Takeuchi Y, Tozaki T, Kikusui T, Hasegawa T, Raudsepp T, Chowdhary BP, Kusunose R, Mori Y.Equine anxiety trait is considered an important temperament in various situations, including riding, training, and daily care. This study examined the polymorphism of the equine serotonin transporter (SLC6A4) gene as a candidate genetic element influencing equine anxiety trait. The sequence of the coding region of this gene was highly homologous with those of other mammals, and four single nucleotide polymorphisms were found by comparing the sequences of ten genetically unrelated thoroughbred horses. Radiation hybrid mapping revealed that this gene was located 26.92 cR from neurofibromin 1 on ...
Tirosh-Levy S, Steinman A.Equine encephalosis (EE) is an arthropod-borne, noncontagious, febrile disease of horses. It is caused by EE virus (EEV), an Orbivirus of the Reoviridae family transmitted by Culicoides. Within the EEV serogroup, seven serotypes (EEV-1-7) have been identified to date. This virus was first isolated from a horse in South Africa in 1967 and until 2008 was believed to be restricted to southern Africa. In 2008-2009, isolation of EEV in an outbreak reported from Israel demonstrated the emergence of this pathogen into new niches. Indeed, testing in retrospect sera samples revealed that EEV had alread...
Jeffcott LB.The mechanism of transfer of maternal immunity to the foal is reviewed. Maximal efficiency of macromolecular absorption by specialized cells of the small intestine exists soon after birth. The absorptive cells are progressively replaced by more mature-looking cells incapable of taking up large molecules and the rate of absorption is reduced in a linear decline and ceases completely within 24 hr. Passive antibody levels fall rapidly in the first 4 weeks of life to less than half their original values and have usually completely disappeared by 6 months of age. The foal shows immunological compet...
Matsui K, Sugano S, Amada A.Changes of the heart rate and ECG to twitching were examined using 5 Thoroughbred foals at various ages and their mares. The effect of the heart rate decrease to twitching was significantly greater in the foals than in the mares. The decreased heart rate in the foals continued during and after the twitching. Changes of the T wave in the A-B lead ECG shown as enhancement of the negative ingredient of the T wave were observed both in the foals and in the mares, accompanied by a decrease in the heart rate during and/or after the twitching. Two out of the five foals showed second-degree A-V block ...
Smith MR, Wright IM.Although fractures of the proximal phalanx are one of the most common long bone fractures of Thoroughbred horses in training, limited details on variations in morphology and radiological progression have been published. Objective: To describe in detail the configuration of parasagittal fractures of the proximal phalanx in a group of Thoroughbred racehorses, to report fracture distribution within this group of horses and to document radiological progression of fracture healing in cases treated by internal fixation. Methods: Restrospective case series. Methods: Case records and radiographs of Th...
Winkelmayr B, Peham C, Frühwirth B, Licka T, Scheidl M.Force transmission under an English saddle (ES) at walk, trot and canter is commonly evaluated, but the influence of a side saddle (SS) on the equine back has not been documented. Objective: Force transmission under a SS, with its asymmetric construction, is different from an ES in walk, trot and canter, expressed in maximum overall force (MOF), force in the quarters of the saddle mat, and centre of pressure (COP). The biomechanics of the equine back are different under a SS compared to ES. Methods: Thirteen horses without clinical signs of back pain ridden in an indoor riding school with both...
Lemazurier E, Séralini GE.Our previous work showed that stallion testis produces high amounts of estrogens which are subsequently found in the ejaculate. These estrogens are mainly synthesized by testicular aromatase, and the major estrogen produced is estrone sulfate (E1S). The objective of this study was to investigate the potential role of E1S as a source of estrogens in the male and female horse reproductive tracts by determining whether both estrone sulfatase (Sulf) and 17beta-hydroxysteroid dehydrogenase type I (17beta-HSD1) activities were present in equine testes, epididymis and uterus. We assessed E1S bioconve...
Hurd HS, McCluskey BJ, Mumford EL.To identify management factors affecting the risk of animals developing vesicular stomatitis (VS). Methods: Case-control study. Methods: Horses, cattle, and sheep with suspected vesicular stomatitis on 395 premises in Colorado, New Mexico, Utah, and Arizona. Methods: Data were collected during the VS outbreak of 1997. Diagnosticians interviewed livestock owners and completed a supplemental questionnaire. Cases were defined as those premises that had a completed questionnaire and had > or = 1 animal positive for VS. Control premises were all premises investigated that had a completed questionna...
Nowakowicz-Dębek B, Pawlak H, Wlazło Ł, Kuna-Broniowska I, Bis-Wencel H, Buczaj A, Maksym P.A growing interest in the horse business has resulted in the increased engagement of many people in this area, and the health problems occurring among workers create the need to search for prophylactic measures. Objective: The objective of the study was evaluation of the level of exposure to air pollution in a stable, and estimation of the degree of work load among workers engaged in tending horses. Methods: The study was conducted twice, during the winter season, in a stable maintaining race horses, and in a social room. In order to evaluate workers' exposure, air samples were collected by th...
Milne EM, Doxey DL, Woodman MP, Cí·¯ord D, Pearson RA.A clinical trial was carried out to determine the effect of cisapride on rate of passage of digesta and clinical parameters in horses with chronic grass sickness. Sixteen horses were given intramuscular cisapride (0.1 mg kg-1 three times daily) (group I), and 15 received oral cisapride (0.8 mg kg-1 three times daily) (group O). A liquid-phase marker (cobalt-EDTA) and a solid-phase marker (polystyrene pellets) were given by stomach tube at the beginning of each of three consecutive 7 day periods, i.e., before, during and after cisapride therapy. Seven horses in each group completed the rate of ...
Sams RA.This article is intended to give the reader an understanding of the mathematic and conceptual framework underlying equine pharmacology. The methods by which the veterinary practitioner determines drug concentrations, disposition, and bioavailability are discussed.
Lefranc AC, Allen WR.The maintenance of luteal function is essential for the
establishment of pregnancy in all mammals. While the lifespan of
the corpus luteum (CL) is independent of the presence of a
conceptus in carnivores (Lawson and Findlay 1977), prolongation
of luteal function in polyoestrous animals requires the presence of
the conceptus to defuse and suppress the cyclical luteolytic
mechanism in the nonpregnant state (Short 1969). In the horse, the
conceptus remains spherical and unattached (Van Niekerk and
Allen 1975) after it enters the uterus between 144 and 168 h after
ovulation (Battut et al....
Zabek T, Golonka P, Fornal A, Semik E.Genetic polymorphism of IHH gene were investigated in Angloarabian, Polish Coldblood and Polish Halfbred horses with the inclusion of a group of Polish Halfbreds affected by osteochondrosis. IHH is a good candidate gene for association study of developmental disorders mainly affecting skeleton development. DNA sequence spanning IHH gene annotated in the horse genome and its putative promoter were investigated using SANGER sequencing. Analysis of genetic variability at polymorphic sites in the IHH gene body and the promoter region confirmed genetic differences between warmblood and coldblood ho...
Russell AP, Slone DE.Medical records of 70 horses diagnosed with left laryngeal hemiplegia that were treated by use of prosthetic laryngoplasty combined with bilateral ventriculectomy were examined. Degree of arytenoid cartilage abduction that had resulted from the prosthesis had been graded before the horse was discharged from the hospital. Follow-up information through owner/trainer questioning was acquired for 55 horses. Information concerning the type and frequency of complications, if any, was recorded, along with a determination of owner/trainer satisfaction regarding surgical results. Race records were acqu...
Moran G, Folch H, Henriquez C, Ortloff A, Barria M.Reaginic antibodies (IgE and some IgG subclasses) and mast cells play important roles in the induction of type I immediate hypersensitivity reactions. These antibodies bind through their Fc fragment to high affinity receptors (FcεRI) present in the membrane of mast cells and basophils. The cross-linking of the receptor initiates a coordinated sequence of biochemical and morphological events that results in exocytosis of secretory granules containing pre-formed inflammatory mediators, secretion of newly formed lipid mediators, and secretion of cytokines. Previously, several studies have invest...
Gastal EL, Gastal MO, Ginther OJ.Ultrasonically detected changes in the equine preovulatory follicle were characterized for the 3 d preceding ovulation early (n = 47) and late (n = 14) in the ovulatory season. Values for the following follicle end points increased progressively over the 3 d: diameter, incidence of nonspherical shape, echogenicity of the apparent granulosa layer, and prominence of an anechoic layer beneath the granulosa. The latter 2 echotexture end points were scored from 1 to 3 (minimal to maximal). Follicle diameter and the 2 echotexture characteristics were more prominent early than late in the ovulatory s...
McDonnell SM.This article includes a brief description of the reproductive patterns and specific behaviors comprising courtship and copulation in equids. The author then focuses on breeding behavior of the domestic stallion. Descriptions of normal breeding behavior under a variety of domestic management systems, comments on sexual behavior of donkeys and exotic equids, and the most common types and treatments of sexual behavior dysfunction are included.
Ferris RA, Dern K, Veir JK, Hawley JR, Lappin MR, McCue PM.To develop a broad-range 28S ribosomal DNA quantitative PCR (qPCR) assay for detection of fungal DNA in equine endometrial samples. Methods: 12 fungal samples from a clinical diagnostic laboratory and 29 samples obtained from 17 mares. Methods: The qPCR assay was optimized with commercially acquired fungal organisms and validated with samples obtained from the clinical diagnostic laboratory. Subsequently, 29 samples from 17 mares suspected of having fungal endometritis were evaluated via the qPCR assay and via traditional fungal culture and endometrial cytology. Amplicons from the qPCR assay w...
Carlson GP, Jones JH.This study was undertaken to evaluate the effects of frusemide on the concentration of plasma electrolytes and the relationship between changes in electrolyte concentration and the simultaneous changes in acid-base balance in arterial and venous blood during intense exercise. Five exercise-conditioned Thoroughbred horses were exercised on a high-speed treadmill at a slope of 10% at speeds known to exceed VO2max. Horses participated in 3 randomised exercise trials in which they received either placebo (control), low-dose frusemide (0.5 mg/kg bwt), or high-dose frusemide (1.0 mg/kg) 4 h prior to...
Carroll HK, Bott-Knutson RC, Mastellar SL.Two surveys of equine owners/managers and professionals using convenience sampling via multimodal distribution were conducted on perceptions of equid health and well-being (n = 142) and equine nutrition and feeding practices (n = 151). Surveys were distributed in 2014-2015 (health and well-being) and 2016 (nutrition and feeding) to similar email lists and social media sites; both included questions regarding information-seeking preferences. Respondents were mostly female (62% health and well-being, 84% nutrition and feeding) and had over 20 years of equine ownership/management experience (4...
Asano K, Suzuki K, Chiba M, Sera K, Matsumoto T, Asano R, Sakai T.The influence of atrioventricular block (AV-block) on the trace elemental status in a horse hair was studied. The particle-induced X-ray emission (PIXE) method has provided a reliable, rapid, easy, and relatively inexpensive diagnostic method. Twenty-five elements (Al, Br, Ca, Cl, Co, Cu, Cr, Fe, Hg, K, Mg, Mn, Na, Nb, Ni, P, Pb, Rb, S, Se, Si, Sr, Ti, Y, and Zn) in mane hair and serum were measured by the PIXE method. A horse hair with first- and second-degree AV-block contained significantly greater amounts of Br, Ca, Sr, and Zn than those of horses without electrocardiographic abnormalities...
Keegan KG, Wilson DA, Kreeger JM, Ellersieck MR, Kuo KC, Li Z.To evaluate the distribution of mepivacaine hydrochloride after distal interphalangeal (DIP) joint injection in horses. Methods: Prospective, uncontrolled study. Methods: 10 adult horses. Methods: 30 minutes before euthanasia, 8 ml of 2% mepivacaine hydrochloride was injected into the dorsal pouch of a forelimb DIP joint. Synovial tissue from the DIP joint and podotrochlear (navicular) bursa and bone tissue from the medullary cavity of the distal sesamoid (navicular) bone were taken from both forelimbs immediately after death. All synovial and bone specimens were analyzed for tissue concentrat...
McDaniel AL, Martin SA, McCann JS, Parks AH.The objective of this study was to examine the effects of Aspergillus oryzae fermentation extract on the in vitro equine cecal fermentation of soluble starch, amino acids/peptides, coastal bermudagrass hay, and alfalfa hay. Cecal contents were obtained from a cecally fistulated Quarter Horse gelding fed coastal bermudagrass and grain (70:30) either unadapted or adapted to dietary A. oryzae supplementation (2 g/d). Mixed cecal microorganisms were incubated in anaerobic media for either 24 h (soluble starch, amino acids) or 48 h (bermudagrass hay, alfalfa hay). A. oryzae was added to the incubat...
Gong ZL, Liu GY, Xie JR, Chai HP, Zhang LY, Li ZX, Tian ZC, Wang L, Liu JG.To clone and express BC48 gene of Babesia caballi, and to establish an indirect ELISA for the diagnosis of B. caballi in equine animals. Methods: The genomic DNA of B. caballi was extracted from the infected donkey blood. BC48 gene was amplified by PCR. The PCR product was cloned into expression plasmid pET28a, and expressed in E. coli BL21 with IPTG induction. The recombinant protein was purified by Ni-NTA affinity chro-matography and was used as a diagnostic antigen to establish an indirect ELISA. The reaction conditions of the indirect ELISA were optimized. Specificity and sensitivity of th...
Marshall C.Erythema multiforme is reported for the first time in 2 South African horses. Both horses displayed a sudden, fulminant outbreak of raised, non-alopecic and non-pruritic plaques over the dorsolateral aspects of the neck and trunk. In both cases the distribution of the lesions was bilaterally symmetrical. Histopathological findings included hydropic degeneration of basal epidermal cells, eosinophilic necrosis of individual or groups of keratinocytes, intra-epidermal and sub-epidermal cleft formation and mixed, dermal, perivascular infiltrates. An initiating cause could not be identified in eith...
Carter SD, May C, Barnes A, Bennett D.Antibody levels (IgG and IgM) to Borrelia burgdorferi were measured in the sera and synovial fluids of UK horses. Western blotting against B. burgdorferi was also used on samples from seropositive horses. A low incidence of seropositivity was shown in horses from most parts of the UK. This increased in areas that have a high incidence of human and canine borreliosis (Norfolk and south coast). Leptospira infections of horses did not cause cross reactions in the B. burgdorferi ELISA. Most horses did not display clinical signs of Lyme disease. As with dogs and man, it is apparent that B. burgdorf...
Moss AL, Hritz RL, Hector RC, Wotman KL.To investigate the effects of orally administered trazodone on intraocular pressure (IOP), pupil diameter measured in the vertical plane (ie, vertical pupil diameter [VPD]), selected physical examination variables, and sedation level in healthy equids. Methods: 7 horses and 1 pony. Methods: Food was withheld for 12 hours prior to drug administration. After baseline (time 0) sedation scoring, physical examination, and measurement of IOP and VPD, equids received 1 dose (approx 6 mg/kg) of trazodone orally. Examination and measurement procedures were repeated 0.5, 1, 2, 4, 8, 12, and 24 hours aft...
Gilchrist P, Sergeant ES.Australia has the world's largest population of wild equids and equine influenza (EI) was confirmed on several properties in New South Wales (NSW) close to uncontrolled areas of land during the 2007 outbreak. Likelihood and risk management assessments were carried out to determine the risk of EI infection of the wild horse populations. The likelihood of spread to the wild horse population was determined to be extremely low, but the likelihood of spread from an established wild horse reservoir back to domestic horses was considered high. The most effective mechanism of control was determined to...
Murakami S, Otaki M, Hayashi Y, Higuchi K, Kobayashi T, Torii Y, Yokoyama E, Azuma R.Recently, submandibular abscesses associated with Actinomyces denticolens have been reported in horses. The actinomycotic clumps have been observed in the tonsillar crypts. The aim of this study was to demonstrate colonisation of A denticolens in equine tonsils. Twelve equine tonsils obtained from a slaughterhouse were divided into two parts for histopathological examination and for isolation of A denticolens. When actinomycotic clumps were found in these tonsillar crypts, immunohistochemistry using hyperimmune serum against A denticolens (DMS 20671) was performed on the serial sections. To de...
