Equine diseases encompass a wide range of health conditions that can affect horses, including infectious diseases, metabolic disorders, and genetic conditions. These diseases can impact the overall health, performance, and well-being of horses. Common equine diseases include equine influenza, equine herpesvirus, laminitis, and equine metabolic syndrome. Diagnosis and management of these diseases often require a combination of clinical evaluation, laboratory testing, and appropriate treatment strategies. This page gathers peer-reviewed research studies and scholarly articles that explore the etiology, pathophysiology, diagnosis, and treatment options for various equine diseases, providing valuable insights for veterinarians and researchers in the field.
Folsom RW, Littlefield-Chabaud MA, French DD, Pourciau SS, Mistric L, Horohov DW.Equine influenza virus remains a major health concern for the equine industry in spite of ongoing vaccination programmes. Previous work has shown that the immune system of horses can be affected by strenuous exercise. The possible adverse consequence of exercise-induced alterations in lymphocyte responses measured in vitro was unknown. Here we demonstrate that subjecting vaccinated ponies to a 5 day strenuous exercise programme results in a significant suppression of their T cell-mediated immune response to equine influenza virus as measured by decreased lymphoproliferation and gamma interfero...
McMonagle EL, Taylor S, van Zuilekom H, Sanders L, Scholtes N, Keanie LJ, Hopkins CA, Logan NA, Bain D, Argyle DJ, Onions DE, Schijns VE, Nicolson L.Interleukin-12 (IL-12) is a key cytokine in the development of cell-mediated immune responses. Bioactive IL-12 is a heterodimeric cytokine composed of disulphide linked p35 and p40 subunits. The aim of this study was to verify biologically activity of the products expressed from equine interleukin-12 (IL-12) p35 and p40 cDNAs and to establish whether equine IL-12 could be expressed as a p35/p40 fusion polypeptide, as has been reported for IL-12a of several mammalian species. We report production of equine IL-12 through expression of p35 and p40 subunits in mammalian and insect cells and of a p...
O'Rourke JP, Newbound GC, Kohn DB, Olsen JC, Bunnell BA.This report compares gene transfer efficiencies as well as durations and levels of gene expression for human immunodeficiency virus (HIV) and equine infectious anemia virus (EIAV) lentiviral vectors in a variety of human cell types in vitro. EIAV and HIV vectors transduced equivalent numbers of proliferating and G1/S- and G2/M-arrested cells, and both had very low efficiencies of transduction into G0-arrested cells. Analysis of the levels of both the enhanced green fluorescent protein (EGFP) and mRNA demonstrated that the HIV-transduced cells expressed greater levels of EGFP protein and RNA th...
Eder C, Curik I, Brem G, Crameri R, Bodo I, Habe F, Lazary S, Sölkner J, Marti E.To investigate whether allergen-specific IgE production is influenced by environmental and genetic factors, IgE levels against 2 mould extracts (Alternaria alternata [Alt a] and Aspergillus fumigatus [Asp f]) and against recombinant (r) rAlt a 1, rAsp f 7 and rAsp f 8 were determined by ELISA in sera from 448 Lipizzan horses living in 6 studfarms. Statistical evaluation showed a significant effect of studfarm-specific environment on IgE levels against the different allergens, but genetic factors also influenced allergen-specific IgE production: an heritability of 0.33 was found for IgE levels ...
Busoni V, Denoix JM.The purpose of this paper is to describe the technique for ultrasonographic examination of the podotrochlear apparatus in the horse using a transcuneal approach. In this study, ultrasound scans were performed in 3 normal cadaver limbs and 5 sound horses and images were compared to anatomic sections to establish the normal ultrasonographic anatomy of the podotrochlear apparatus. Detailed description of transverse and sagittal reference ultrasonographic images of this region is provided. This new imaging technique allows the assessment of the distal sesamoid bone flexor surface, the distal porti...
Cherdchutham W, Meershoek LS, van Weeren PR, Barneveld A.To determine the effects of exercise on biomechanical properties of the superficial digital flexor tendon (SDFT) in foals. Methods: 43 Dutch Warmblood foals. Methods: From 1 week until 5 months of age, 14 foals were housed in stalls and not exercised, 14 foals were housed in stalls and exercised daily, and 15 foals were maintained at pasture. Eight foals in each group were euthanatized at 5 months, and remaining foals were housed together in a stall and paddock until euthanatized at 11 months. After euthanasia, SDFT were isolated and fit in a material testing system. Mean cross-sectional area ...
Tetens J, Venugopal CS, Holmes EP, Koch CE, Hosgood G, Moore RM.To evaluate the in vitro effects of adenosine tryphosphate (ATP) on vasomotor tone of equine colonic vasculature. Methods: Arteries and veins from the left ventral colon of 14 mixed-breed horses euthanatized for reasons unrelated to cardiovascular or gastrointestinal tract disease. Methods: Endothelium-intact and -denuded arterial and venous rings were precontracted with 10(-7) and 1.8 x 10(-8) M endothelin-1, respectively. In 1 trial, endothelium-intact rings were also incubated with 10(-4) M N omega-nitro-L-arginine methyl ester (L-NAME) to inhibit nitric oxide (NO) production. Adenosine tri...
Wilson AD, Harwood LJ, Björnsdottir S, Marti E, Day MJ.We postulated that all horses exposed to the bites of Culcoides (midges) would have an antibody response to the antigen secreted in Culcoides saliva, but that IgE antibody would be restricted to allergic individuals. Using immunohistology on sections of fixed Culicoides, we have demonstrated the presence of antibodies in horse serum which recognise Culicoides salivary glands. Antibodies were detected in the serum of horses with insect dermal hypersensitivity and in the serum of normal horses exposed to Culicoides bites. In contrast, no antibodies were detected in serum from native Icelandic po...
McClure JT, DeLuca JL, Lunn DP, Miller J.The purpose of this study was to evaluate the ability of an equine plasma product i.v. and a concentrated serum product i.v. to deliver antibodies to 46 foals with failure of passive transfer (FPT). Treatment of FPT was as per manufacturers recommendations, using plasma (950 ml/unit) or a concentrated serum product (250 ml/unit). Significant variables affecting the 3 day post-transfusion serum immunoglobulin G (IgG) concentration of foals included body weight, pretransfusion IgG concentration, number of product units transfused, foaling season and product administered. Plasma treatment had a g...
Chambers TM, Holland RE, Tudor LR, Townsend HG, Cook A, Bogdan J, Lunn DP, Hussey S, Whitaker-Dowling P, Youngner JS, Sebring RW, Penner SJ....Flu Avert IN vaccine is a new, live attenuated virus vaccine for equine influenza. We tested this vaccine in vivo to ascertain 1) its safety and stability when subjected to serial horse to horse passage, 2) whether it spread spontaneously from horse to horse and 3) its ability to protect against heterologous equine influenza challenge viruses of epidemiological relevance. For the stability study, the vaccine was administered to 5 ponies. Nasal swabs were collected and pooled fluids administered directly to 4 successive groups of naïve ponies by intranasal inoculation. Viruses isolated from th...
Watt BC, Edwards RB, Markel MD, McCabe R, Wilson DG.To compare the biomechanical characteristics and mode of failure of two different dynamic compression plate (DCP) techniques for proximal interphalangeal joint (PIPJ) arthrodesis in horses. Methods: Randomized block-design blocking on horse (1-5), method of fixation (two 7-hole, 3.5-mm broad DCP vs two 5-hole, 4.5-mm narrow DCP), side (left, right), and end (front, hind). Constructs were loaded to failure in 3-point bending in a dorsal-to-palmar (plantar) direction. Methods: Ten paired limbs from 5 equine cadavers. Methods: Two 7-hole, 3.5-mm broad dynamic compression plates (bDCP) were used i...
Rodgerson DH, Belknap JK, Moore JN, Fontaine GL.To determine messenger RNA expression of cyclooxygenase (COX)-2, tumor necrosis factor (TNF)-alpha, and interleukin- (IL)-1beta from cultured equine smooth muscle cells (SMC). Methods: Segments of palmar digital artery harvested from 6 clinically normal adult horses. Methods: Explants were collected from the tunica media of arteries for primary culture of SMC. Equine mononuclear cells were used as control cells. Subcultured vascular SMC and control cells were exposed to lipopolysaccharide (20 microg/ml and 100 ng/ml, respectively). Northern blot analysis with equine-specific probes for COX-2, ...
Goulden B.Abstract Extract A series of landmark studies on the function of the equine larynx was conducted by a group of researchers at Massey University between 1970 and 1987. These studies commenced with investigations on the normal laryngeal anatomy and physiology (Goulden et al 1976a; Anderson et al 1980; Quinlan et al 1982), and progressed to a clinical appraisal of laryngeal hemiplegia, the most important clinical disease affecting the horse's larynx (Goulden and Anderson 198 lab, 1982). The studies concluded with a series of in-depth cytological and pathological studies of the intrinsic laryngeal...
Duncan JL, Abbott EM, Arundel JH, Eysker M, Klei TR, Krecek RC, Lyons ET, Reinemeyer C, Slocombe JO.These guidelines have been designed to assist in the planning, operation and interpretation of studies which would serve to assess the efficacy of drugs against internal parasites of horses. Although the term anthelmintic is used in the title and text, these guidelines include studies on drug efficacy against larvae of horse bot flies, Gasterophilus spp., which are non-helminth parasites commonly occurring in the stomach of horses. The advantages, disadvantages and application of critical and controlled tests are presented. Information is also provided on selection of animals, housing, feed, d...
Schobesberger H, Peham C.The purpose of this study was to investigate whether artificial neural networks could be used to determine equine lameness by computational means only. The integral parts of our approach were the combination of automated signal tracking of horses on a treadmill and the computational power of artificial neural networks (ANN). The motion of 175 horses trotting on a treadmill was recorded using the SELSPOT II system for motion analysis. Two cameras traced infrared (IR) markers on the head and on the left forehoof. The motion of the head was Fourier-transformed and further processed by a multilaye...
Lin C, Holland RE, Donofrio JC, McCoy MH, Tudor LR, Chambers TM.Equine influenza virus (EIV) is the leading cause of acute respiratory infection in horses worldwide. In recent years, the precise mechanism by which influenza infection kills host cells is being re-evaluated. In this report, we examined whether caspases, a group of intracellular proteases, are activated following EIV infection and contribute to EIV-mediated cell death. Western blotting analysis indicated that a nuclear target of caspase-3, poly(ADP-ribose) polymerase (PARP) was proteolytically cleaved in EIV-infected MDCK cells, but not in mock-infected cells. In comparison with caspase-3 spe...
Riggs CM.Fractures are a common cause of loss among Thoroughbred racehorses. A large proportion of these injuries occurs in the absence of a specific traumatic event and show typical characteristics of stress fractures. The fractures show a high degree of consistency in their morphology; they frequently share the same locations as incomplete cracks and they are often associated with pre-existing pathology (periosteal and endosteal new bone formation and intracortical remodelling). Bone is able to adapt to changes in its mechanical environment. Studies of the Thoroughbred racehorse show modification of ...
Metcalf ES.Despite the numerous benefits of having the capability to transport semen internationally, there are serious potential ramifications if that semen is contaminated with a communicable disease. Bacteria: Many commensal bacteria colonize the exterior of the stallion penis and are not regarded as pathogenic. They may be cultured from an ejaculate. Alterations of the normal bacterial flora on the exterior genitalia may cause the growth of opportunistic bacteria such as Klebsiella pneumonia, Pseudomonas aeruginosa, Streptococcus zooepidemicus, which, if inseminated, may cause infertility in suscepti...
Gadella BM, Rathi R, Brouwers JF, Stout TA, Colenbrander B.During sexual reproduction, the sperm and oocyte must fuse before the production of a diploid zygote can proceed. In mammals such as equids, fusion depends critically on complex changes in the plasma membrane of the sperm and, not surprisingly, this membrane differs markedly from that of somatic cells. After leaving the testes, sperm cease to synthesize plasma membrane lipids or proteins, and vesicle-mediated transport stops. When the sperm reaches the female reproductive tract, it is activated by so-called capacitation factors that initiate a delicate reorientation and modification of molecul...
Rigby SL, Brinsko SP, Cochran M, Blanchard TL, Love CC, Varner DD.This study evaluated motility and fertility of uncentrifuged and centrifuged equine semen following dilution in a skim milk-glucose extender with or without supplemental Tyrode's medium. In addition, the effect of seminal plasma addition to each extender was evaluated. For Experiment 1, motility of 48h cooled, stored spermatozoa was evaluated following eight dilution treatments: uncentrifuged and diluted 1:4 (v/v) in skim milk-glucose extender (EZ Mixin CSTJ; CST-1:4) or in CST supplemented 65:35 (v/v) with modified Tyrode's medium (KMT-1:4); uncentrifuged and diluted to 25x10(6) spermatozoa/m...
Meyers SA.The plasma membrane over the sperm head of several mammalian species has been shown to express a glycerolphosphatidylinositol-linked hyaluronidase known as PH-20. This protein has been associated with the sperm's interaction with the oocyte cumulus matrix and zona pellucida. The characteristics of PH-20 in equine sperm have not been clearly defined. In this study, ejaculated gel-free semen from five stallions and epididymal sperm from isolated epididymis from 10 stallions was used to characterize the PH-20 activity in equine sperm. Affinity purified anti-equine PH-20 polyclonal antibody was us...
Meehan M, Lynagh Y, Woods C, Owen P.The major cell-wall-associated protein of the equine pathogen Streptococcus equi subsp. equi is an M-like fibrinogen-binding protein (FgBP) which binds equine fibrinogen (Fg) avidly, through residues located at the extreme N-terminus of the molecule. In this study, it is shown that FgBP additionally binds equine IgG-Fc. When tested against polyclonal IgG from ten other animal species, it was found that FgBP binds human, rabbit, pig and cat IgG, but does not bind mouse, rat, goat, sheep, cow or chicken IgG. Through the use of a panel of recombinant FgBP truncates containing defined deletions of...
Pemberton AD, McEuen AR, Scudamore CL.Mast cell proteinases are important inflammatory mediators in man and other species, but until now there has been no investigation of the nature of equine mast cell proteinases. These studies describe the purification and characterisation of two proteolytic components from equine mastocytoma tissue, detected using chromogenic substrates for trypsin and chymotrypsin. Following chromatographic purification, the trypsin-like component was found to be equine mast cell tryptase by N-terminal amino acid sequencing, showing a close similarity with human tryptase-beta (85% identity over 20 residues). ...
Hudson JM, Cohen ND, Gibbs PG, Thompson JA.To determine whether specific feeding practices were associated with development of colic in horses. Methods: Prospective matched case-control study. Methods: 364 horses examined by veterinarians in private practice in Texas because of colic (cases; n = 182) or any other reason (controls; 182). Methods: Participating veterinarians were sent forms at the beginning of the study to collect information on signalment, feeding management practices, farm management practices, and preventive medical treatments. Case and control horses were compared by use of conditional logistic regression to identify...
Tsunemitsu H, Imagawa H, Togo M, Shouji T, Kawashima K, Horino R, Imai K, Nishimori T, Takagi M, Higuchi T.A total of 65 equine group A rotaviruses (GAR) isolated from diarrheal foals at 48 farms in Hokkaido, Japan, between 1996 (29 isolates) and 1997 (36 isolates) were characterized for their VP7 and VP4 serotypes by PCR, nucleotide sequencing, and virus neutralization (VN) tests. By PCR VP7 typing, all isolates were classified as G3 or G 14, and the predominant serotype in each year was G3 (86%) in 1996 and G14 (53%) in 1997. VN tests with these 20 isolates randomly selected confirmed the specificity of PCR on the bases of complete agreement of the results in these methods (9 G3 and 11 G14), and ...
Sanchez S, Studer M, Currin P, Barlett P, Bounous D.Listeria monocytogenes is ubiquitous in the environment but is rarely reported as a cause of keratitis in animals. In this case, a mare was presented with epiphora and evidence of pain in the right eye. Listeria monocytogenes was isolated from a corneal lesion, and bacteria were also seen in the cytologic evaluation. This is the first reported case of ulcerative keratitis associated with L. monocytogenes in a horse.
Meershoek LS, Schamhardt HC, Roepstorff L, Johnston C.Lameness in athletic horses is often caused by forelimb tendon injuries, especially in the interosseus tendon (TI) and superficial digital flexor tendon (SDF), but also in the accessory ligament (AL) of the deep digital flexor tendon (DDF). In an attempt to explain the aetiology of these injuries, the present study investigated the loading of the tendons during landing after a jump. In jumping horses, the highest forces can be expected in the trailing limb during landing. Therefore, landing kinematics and ground reaction forces of the trailing forelimb were measured from 6 horses jumping singl...
Roepstorff L, Johnston C, Drevemo S.The objective of this study was to validate a simple method to measure the mediolateral expansion of the heels and to apply this method in an in vivo experiment. It was also the aim to quantify the mediolateral expansion in different areas of the heel using an in vitro model. In the in vitro study, 5 right and 5 left distal forelimb specimens from 5 Standardbreds were mounted vertically in a custom-made compressive test machine. The heel expansion was measured using optical kinematic analysis and a potentiometer system. Specimens were tested unshod, with frog pressure and with the weightbearin...
Weishaupt MA, Wiestner T, Hogg HP, Jordan P, Auer JA, Barrey E.The purpose of this study was to verify the sensitivity of 2 gait analysis methods in detecting subtle lameness and to compare the results to the traditional orthopaedic evaluation. Twenty-two horses were evaluated (1) subjectively by 3 different experienced clinicians and (2) objectively with synchronised ground reaction force and accelerometric gait measurements on a treadmill. The horses were assigned for each of the 3 methods independently to one of 3 groups (GR): sound, lameness front limb, lameness hindlimb. Additionally, for each horse, the affected limb (AL) and degree of lameness (DL)...
Chateau H, Degueurce C, Jerbi H, Crevier-Denoix N, Pourcelot P, Audigié F, Pasqui-Boutard V, Denoix JM.The purpose of this study was to quantify small amplitude rotational movements in the metacarpophalangeal joint (MPJ) of the horse and to measure the influence of asymmetric placement of the foot on these articular angles. Trihedrons, supporting kinematic markers defining a local frame, were screwed into the third metacarpal bone and the proximal phalanx of 4 isolated forelimbs. The limbs were loaded in a press, and the lateral or medial aspects of the foot were raised alternately by a 12 degrees wedge. The use of the joint coordinate system permitted the simultaneous and continuous computing ...
Soma LR, Birks EK, Uboh CE, May L, Teleis D, Martini J.Seven hundred and eighty-eight Standardbred pacers competing in 8378 races at one racetrack were analysed to determine the effects of the administration of prerace frusemide on racing times (RT). Frusemide was administered i.v. 4 h before the race to pacers diagnosed with exercise-induced pulmonary haemorrhage (EIPH). Of the pacers, starting in the 1997 racing season, 32.5% received prerace frusemide. This study demonstrated that administration of frusemide prior to racing significantly decreased RT. There was an overall significant decrease (P<0.00001) in RT of 0.67 s. The overall RT for h...
Duvivier DH, Votion D, Vandenput S, Lekeux P.Inhalation therapy plays an increasing role in the management of equine respiratory disorders. This alternative to systematic treatment permits a high concentration of medication to act locally while minimizing side effects and residues. In human medicine, literature in this field is prolific and continuously renewed, whereas in veterinary medicine, applications of aerosol therapy are less extensive. This review considers the principles of action of the different types of devices used for inhalation, i.e., nebulization, metered-dose inhalation and dry powder inhalation, describes the technical...
Scott JS, Garon H, Broadstone RV, Derksen FJ, Robinson NE.We examined the response of five ponies with recurrent airway obstruction (principals) and five age- and gender-matched controls to the aerosol alpha-adrenergic agonist phenylephrine after blockade with propranolol and atropine. Measurements were made with principal ponies in clinical remission (period A) and during acute airway obstruction (period B). The blockade had no effect on base-line pulmonary mechanics in control ponies during periods A and B or in the principal ponies during period A. However, in the principal ponies during period B, blockade increased dynamic compliance (Cdyn) and d...
Spoormakers TJP, Graat EAM, Serra Bragança FM, Weeren PRV, Brommer H.Lameness assessment in horses is still predominantly performed using subjective methods. Visual assessment is known to have moderate to good intra-rater agreement but relatively poor inter-rater agreement. Little is known about inter- and intra-rater agreement on the evaluation of back motion, for which no objective measurement technique in a clinical setting is available thus far. To describe inter- and intra-rater agreement of visual evaluation of equine back mobility. Rater reliability study using a fully crossed design in which all horses are rated by all observers. This data is compared w...
Reisbig NA, Pifko J, Lanovaz JL, Weishaupt MA, Carmalt JL.Although the temporomandibular joint (TMJ) is the major contact point between the reins in the riders' hand, the bit in the mouth, and the rest of the horse under saddle, the role of inflammation of this joint on equine locomotion and rein tension is unknown. Unassigned: To determine the effect of acute TMJ inflammation on rein-tension and horse movement when horses were long-reined on a treadmill. Unassigned: A randomized, controlled, cross-over design. Unassigned: Five horses were trained by one clinician to walk and trot on a treadmill wearing long-reining equipment instrumented with a rein...
Suvá M, Arnold VH, Wiedenmann EA, Jordan R, Galvagno E, Martínez M, Vichera GD.Somatic cell nuclear transfer (SCNT) is an asexual reproductive technique where cloned offspring contain the same genetic material as the original donor. Although this technique preserves the sex of the original animal, the birth of sex-reversed offspring has been reported in some species. Here, we report for the first time the birth of a female foal generated by SCNT of a male nuclear donor. After a single SCNT procedure, 16 blastocysts were obtained and transferred to eight recipient mares, resulting in the birth of two clones: one male and one female. Both animals had identical genetic prof...
Prakoso D, Dark MJ, Barbet AF, Salemi M, Barr KL, Liu JJ, Wenzlow N, Waltzek TB, Long MT.West Nile virus (WNV), a small, positive sense, single stranded RNA virus continues to encroach into new locales with emergence of new viral variants. Neurological disease in the equine can be moderate to severe in the face of low to undetectable virus loads. Physical methods of virus enrichment may increase sensitivity of virus detection and enhance analysis of viral diversity, especially for deep sequencing studies. However, the use of these techniques is limited mainly to non-neural tissues. We investigated the hypothesis that elimination of equine brain RNA enhances viral detection without...
Cummings JF, de Lahunta A, Summers BA, Mohammed HO, Divers TJ, Valentine BA, Trembicki-Graves K.Equine motor neuron disease (EMND) is a sporadic, progressive neurodegenerative disorder that has been identified recently in horses of different breeds in North America. The cause is unknown. Pathologic changes which occur in spinal and certain brain stem motor neurons include chromatolysis, swelling, neurofilamentous accumulation, and development of eosinophilic cytoplasmic inclusions. Punctate eosinophilic inclusions, the type usually encountered in degenerating neurons, resembled Bunina bodies at the light microscopic level, but differed in their ultrastructural composition. These and less...
Santos FC, Corcini CD, Costa VG, Gheller SM, Nogueira CE, da Rosa Curcio B, Varel AS.Solid storage medium prevents cellular sedimentation, reduces metabolic demand via limiting movement, and avoids the modification of an extender composition in the sedimentary microenvironment. It has been proven to prolong spermatozoa viability in mammalians. Objective: This experiment aims to evaluate the effect of cool storage in solid phase extender on stallion sperms. Methods: Semen was collected from 10 Crioulo stallions (n=30) and submitted to treatments: control group (semen extender) and groups with gelatin addition in different concentrations (semen extender + 1%, 2% and 3%). Seminal...
Bouchey D, Evermann J, Jacob RJ.Examination of six field isolates of equine herpesvirus 3, the causative agent of equine coital exanthema, indicates that all were temperature sensitive (ts) at the body temperature, 39 degrees C, of their host (Equine asinus and callabus) when grown in cell culture. The isolates were characterized by fingerprint analysis with the restriction endonucleases XbaI, EcoRI, BamHI and Hind III to establish possible epidemiologic relatedness. Three of the six isolates may be considered related. Variation in the mobility of the BamHI-A and Hind III-K fragments indicates that a small plaque isolate may...
Murray RC, Blunden TS, Branch MV, Tranquille CA, Dyson SJ, Parkin TD, Goodship AE.To investigate effects of age on thickness and morphologic characteristics of hyaline cartilage, calcified cartilage, total cartilage, and subchondral bone (SCB) in the equine tarsometatarsal joint. Methods: 23 tarsal joints from cadavers of 23 ponies (11 days to 25 years old); ponies were limited to pasture exercise and euthanatized for reasons not related to this study. Procedures-Tarsi were allocated into several age groups (11 days old [n = 3], 6 to 9 months old [4], 2 to 3 years old [3], 6 to 8 years old [4], 11 to 17 years old [6], and 20 to 25 years old [3]). Histologic examination and ...
Ruohoniemi M, Ryhänen V, Tulamo RM.Radiographic findings in the navicular bone and distal interphalangeal joint as well as the ossification status of the collateral cartilages of the distal phalanx were evaluated in 100 Finnhorse cadaver forefeet. The most common shapes of the proximal articular margin of the navicular bone were convex and straight. Remodeling of the navicular bone was common, especially on the lateral extremity. No bony fragments were identified at the distal flexor margin even though this area appeared irregular in several feet. Several large, rounded or lollipop-shaped synovial invaginations were identified ...
Greppi MC, Guillot J, Melloul E, Bourdoiseau G, Lepage O, Cadoré JL.Guttural pouch mycosis (GPM) is a rare but potentially life-threatening condition in horses. GPM is caused by a fungal invasion into the mucosal lining of the guttural pouches and, frequently, the associated neurovascular structures. Although several species of fungi have been associated with this disease, Aspergillus spp. appear to be the most common isolated from the guttural pouches. However, it remains unclear which are the predisposing factors leading to the development of the infection. The objectives of the present study were to experimentally reproduce an infection by Aspergillus fumig...
Contino EK, Park RD, McIlwraith CW.There have been many studies that document radiographic findings in young Thoroughbred and Standardbred horses. No such studies have been performed in Quarter Horses. Objective: To describe the prevalence of radiographic changes in the stifles, tarsi, carpi and fetlocks of young Quarter Horses intended for cutting. Methods: Radiographs of yearling and 2-year-old Quarter Horses were obtained from a radiograph repository and a private farm. The carpi, tarsi, fetlocks and stifles were evaluated and radiographic changes categorised by type and location. The frequency of changes was calculated and ...
Stack A, Derksen FJ, Williams KJ, Robinson NE, Jackson WF.Regional differences in large equine pulmonary artery reactivity exist. It is not known if this heterogeneity extends into small vessels. The hypothesis that there is regional heterogeneity in small pulmonary artery and vein reactivity to sympathomimetics (phenylephrine and isoproterenol) and a parasympathomimetic (methacholine) was tested using wire myography on small vessels from caudodorsal (CD) and cranioventral (CV) lung of 12 horses [9 mares, 3 geldings, 8.67 ± 0.81 (age ± SE) yr, of various breeds that had never raced]. To study relaxation, vessels were precontracted with U46619 (10(-...
Hackett ES, Traub-Dargatz JL, Knowles JE, Tarr SF, Dargatz DA.Arterial blood gas analysis is widely accepted as a diagnostic tool to assess respiratory function in neonates. To the authors' knowledge, there are no published reports of arterial blood gas parameters in normal neonatal foals at altitude. Objective: To provide information on arterial blood gas parameters of normal foals born at 1500 m elevation (Fort Collins, Colorado) in the first 48 h post partum. Objective: Foals born at 1500 m will have lower PaO2 and PaCO2 than foals born at sea level due to low inspired oxygen and compensatory hyperventilation occurring at altitude. Methods: Sixteen fo...
Muir WW, McGuirk SM.The rational therapy of cardiovascular disease in horses requires a thorough knowledge of the pharmacology and pharmacokinetics of several specific drugs (digitalis, digoxin). Calcium solutions, dopamine, and dobutamine are frequently used to treat congestive heart failure in horses. Quinidine, procainamide, lidocaine, and propranolol are used to treat a variety of supraventricular and ventricular arrhythmias. Furosemide, a highly potent loop diuretic, is used to eliminate edema and promote diuresis. A thorough understanding of the applied pharmacology, dosage recommendations, toxicity, and pr...
Ishii H, Shibuya M, Kusano K, Sone Y, Kamiya T, Wakuno A, Ito H, Miyata K, Yamada M, Leung GN.Vadadustat is a newly launched hypoxia-inducible factor stabilizer with anti-anemia and erythropoietic effects; however, its use in horses is expressly forbidden in both racing and equestrian competitions. Following our previous report on the pharmacokinetic study of vadadustat in horse plasma and urine, a long-term longitudinal analysis of vadadustat in horse hair after nasoesophageal administration (3 g/day for 3 days) to three thoroughbred mares is described in this study. Our main objective is to further extend the detection period of vadadustat for the purpose of doping control. Three...
Cornelisse CJ, Robinson NE, Berney CA, Eberhart S, Hauptman JE, Derksen FJ.In vitro, glucocorticoids potentiate vasoconstriction of equine digital vessels to catecholamines and this has been implicated as a mechanism of glucocorticoid-induced laminitis. This observation has never been confirmed in vivo. Objective: To study the effects of glucocorticoid therapy on vasoconstrictor responsiveness in the horse in vivo. Methods: In a blinded, randomised cross-over experiment, 9 horses were treated with either dexamethasone (0.1 mg/kg bwt i.v. q. 24 h) or saline i.v. for 6 days. The changes in local average skin temperature before (baseline) and after intradermal injection...
Szeredi L, Aupperle H, Steiger K.Formalin-fixed, paraffin wax-embedded fetal membranes from 76 cases of equine abortion were examined immunohistochemically for equine herpesvirus (EHV)-1 antigen. Of the 76 cases, 11 had been proved EHV-1-positive by diagnostic methods applied to the aborted fetuses (viral isolation in tissue culture, or immunohistochemical examination, or both). Of the 11 fetal membranes from the virus-positive animals, five gave positive results on immunohistochemical examination, and three on in-situ hybridization; the positive signals were detected in trophoblastic cells and occasionally in monocytes and e...
Cooley PL.When compared with small domestic animals, the horse has unique ocular characteristics (complete bony orbit, well-developed eyelid muscles, a nasal and temporal gray limbal line, granulae iridica, paurangiotic fundus). Knowledge of normal equine ocular anatomy is essential for ocular lesion interpretation. It is important to obtain a full history and general examination before sedation, nerve blocks, or other diagnostic ophthalmic tests are performed. All ocular examinations should include a systematic evaluation of both the anterior and posterior segments. Selection of other diagnostic tests ...
Nikolakopoulos E, Kindahl H, Gilbert CL, Goode J, Watson ED.Mating has been shown in many species to provoke the release of oxytocin (OT). In our study, various stimuli were applied to mares to study release of OT and prostaglandin F(2alpha) (PGF(2alpha)) associated with mating. Blood samples were collected from mares around the time of teasing both in oestrus and dioestrus and at mating. For comparison, blood samples were also collected at the time of manual manipulation of the genital tract and after intrauterine infusion of 500 ml phosphate buffered saline (PBS). Additional samples were collected 16 to 18 h after mating. Mating caused a significant ...
Sentsui H, Inoshima Y, Murakami K, Akashi H, Purevtseren B, Pagmajav O, Sugiura T.Cross reactivity of equine infectious anemia virus (EIAV) antigen prepared using a recombinant baculovirus containing the p26 gene of strain P337-V70 was examined by the agar gel immunodiffusion (AGID) test and enzyme-linked immunosorbent assay (ELISA). Serum samples serially collected from 13 horses experimentally infected with six different EIAV strains (two or three horses per strain) were subjected to the test. Positive reactions were observed in the AGID test and ELISA before or soon after the first feverish period and continued persistently in most of the horses. The results with recombi...
Bertram TA, Jensen AE.Morphology and function of equine neutrophils were evaluated after combination with contagious equine metritis organism (CEMO) or 1 of 2 CEMO lipopolysaccharides (LPS). The 2 LPS (LPS-a; LPS-p) isolated from the CEMO contained 14- and 16-carbon fatty acids, ketodeoxyoctanate, hexose, and heptose, but were morphologically distinct. Neutrophils exposed to LPS had fewer granules, whereas those exposed to CEMO had more granules than did the controls (phosphate-buffered saline solution). Neutrophil iodination was significantly increased with 10 and 25 micrograms of LPS-a, but not significantly alte...
Bucca S, Carli A.Human chorionic gonadotropin (hCG) and dexamethasone have a role in the reproductive management protocols of mares susceptible to persistent mating-induced endometritis (PMIE). However, it is possible that there is interference between these 2 drugs. Objective: The objective of this retrospective study was to determine the efficacy of hCG to induce ovulation in mares treated with dexamethasone at breeding time. Methods: Medical records from 152 mares and 223 cycles were analysed. In 113 cycles, mares susceptible to PMIE were treated with 1500 iu hCG and a single dose of 50 mg dexamethasone, 11...
Olivier-Carstens A.Ultrasonographic examinations were performed on the solar aspect of the distal phalanx of 10 feet of five normal live horses (Group 1), 22 feet of seven normal cadavers (Group 2), and nine feet of five horses with pathology of the dorsal solar aspect of the distal phalanx (Group 3). Lateromedial radiographs of the distal phalanx were made in all groups, and in Group 2, digits were sagitally sectioned after imaging. The ultrasonographic and radiographic appearance of the sagittal solar aspect of the distal phalanx was described. Measurements of the distance between the sole and the distal tip o...
Araujo JM, Araújo JV, Braga FR, Carvalho RO.Three isolates of predator fungi Duddingtonia flagrans (AC001), Monacrosporium thaumasium (NF34), and Arthrobotrys robusta (I-31) were assessed in in vitro test regarding the capacity of prey infective larvae (L(3)) Strongyloides westeri. Compared to control, without fungus, there was a significant decrease (P 0.01) in vitro test. Linear regression coefficients of treated and control groups were -0.21 for control, -0.32 for D. flagrans, -0.34 for M. thaumasium, and -0.22 for A. robusta. In the following, isolates AC001 and NF34 were assessed in vivo regarding the capacity of supporting the pa...
Hughes C, Lehner F, Dirikolu L, Harkins D, Boyles J, McDowell K, Tobin T, Crutchfield J, Sebastian M, Harrison L, Baskin SI.An epidemiological association among black cherry trees (Prunus serotina), eastern tent caterpillars (Malacosoma americana), and the spring 2001 episode of mare reproductive loss syndrome in central Kentucky focused attention on the potential role of environmental cyanogens in the causes of this syndrome. To evaluate the role of cyanide (CN (-)) in this syndrome, a simple, rapid, and highly sensitive method for determination of low parts per billion concentrations of CN (-) in equine blood and other biological fluids was developed. The analytical method is an adaptation of methods commonly in ...
Carver DA, Ball BA.Previous studies have demonstrated a detrimental effect of seminal plasma on the maintenance of motility of cooled equine spermatozoa; however, the mechanism for the adverse effect of seminal plasma during cooled storage remains undetermined. In goats, a glycoprotein component of bulbourethral gland secretion contains lipase activity that is detrimental to sperm motility when stored in skim milk-based extenders. The objective of the current study was to determine the amount of lipase activity in stallion seminal plasma and to determine the effect of added lipase on spermatozoal motility during...
Souza EAR, Araujo AC, Pires LCSR, Freschi CR, Azevedo SS, Machado RZ, Horta MC.Equine piroplasmosis, an economically important disease in horses, has so far not been reported in Pernambuco state, Brazil. This study aimed to evaluate the seroprevalence of anti-Babesia caballi and anti-Theileria equi antibodies based on the detection of these agents in equine blood and in ticks on horses in the municipality of Petrolina, Pernambuco, northeastern Brazil. Blood samples were drawn from 393 horses and sera were examined by ELISA. The presence of tick infestations was evaluated, and 101 ticks were subjected to DNA amplification for the detection of Babesia spp. by polymerase ch...
