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.
Belknap JK.The treatment of laminitis has been fraught with confusion and controversy for several decades, mainly because of a lack of understanding of the pathophysiology of the disease process. However, recent advances in laminitis research have greatly improved our understanding of the disease process. This article discusses the various treatment options for laminitis in the context of the findings of recent scientific investigations of laminitis pathophysiology.
Grønvold AM, L'Abée-Lund TM, Strand E, Sørum H, Yannarell AC, Mackie RI.Antimicrobial treatment is associated with the spread of antimicrobial resistance and disturbances in the ecological balance of intestinal microbiota. In horses, the main adverse effect of antimicrobial treatment is colitis. We used culture and 16S rRNA gene based molecular methods to monitor the prevalence of antimicrobial resistance and changes in predominant fecal populations during penicillin treatment and general anesthesia of horses in the clinical setting. After 5 days of parenteral administration of penicillin, fecal Escherichia coli were resistant to multiple unrelated antimicrobial a...
Steward ML.This article describes the use of the wooden shoe in the treatment of chronic laminitis. The shoe, designed to provide a solid base and full roller motion, offers mechanical advantages and enables reduction and redistribution of forces within the hoof capsule.
Abbott Y, Leggett B, Rossney AS, Leonard FC, Markey BK.A retrospective analysis and prospective surveillance study were conducted to determine isolation rates of meticillin-resistant Staphylococcus aureus (MRSA) in dogs, cats and horses in Ireland. Clinical samples that had been submitted to University College Dublin (UCD) for routine microbiological examination over a four-year period (2003 to 2006) were analysed in the retrospective analysis, which included clinical samples from 3866 animals. In the prospective surveillance study, samples from healthy animals presenting for elective surgery as well as from animals with a clinical presentation su...
Echigoya Y, Okabe H, Itou T, Endo H, Sakai T.Muscle glycogen synthase (GYS1) is the rate-limiting enzyme in glycogen synthesis, and its activity is regulated by the phosphorylation states of certain amino acid residues encoded by the GYS1 gene. In the present study, the authors molecularly characterized the full-length equine GYS1 (eGYS1) cDNA and found that it contains a less common polyadenylation signal (AATACA). An amino acid alignment with other mammalian GYS1 showed that the phosphorylation sites in eGYS1 are completely conserved. Genomic DNA analysis revealed that the equine-specific substitutions (Glu 16 Asp and Ala 252 Thr) were...
Larsen ML, Ritz C, Petersen SL, Nielsen MK.Ivermectin resistance has recently been described in Parascaris equorum and there have been reports from several countries of a shortened egg reappearance period (ERP) following ivermectin treatment for cyathostomins. This study was aimed at determining the efficacy of ivermectin in treating cyathostomins and P. equorum in Danish horses. A total of 196 animals were selected from 52 farms, all of which were using a selective anthelmintic treatment strategy. ERP was investigated with weekly samples from 96 horses from nine farms. Horses were treated with ivermectin oral paste by their owners at ...
Austbø L, Røed KH, Dolvik NI, Skretting G.The aim of this study was to investigate genes for differential expression in cartilage of foals predisposed to osteochondrosis (OC). Tissue was sampled from the cranial part of the distal intermediate ridge of the tibia in the tarso-crural joint. Foals were considered predisposed to OC when parents had OC at the distal intermediate ridge of the tibia. RNA was isolated and subjected to arbitrarily primed PCR (RAP-PCR) followed by fingerprinting to screen for differentially expressed genes. By verification of results from the RAP-PCR fingerprint screening using real-time RT-PCR, we identified t...
Mellor DJ.About a decade ago, concern was expressed that fetuses might suffer while dying in utero after the death of their dams. However, reference to already published literature provided compelling evidence that fetuses cannot consciously experience negative sensations or feelings, such as breathlessness and pain, and showed that, provided certain precautions are taken, they cannot suffer--their welfare is assured. In this article, I outline the major features of fetal and neonatal physiology that underlie this conclusion as it relates to fetuses that are neurologically exceptionally immature, modera...
Pronost S, Léon A, Legrand L, Fortier C, Miszczak F, Freymuth F, Fortier G.Equine herpesvirus 1 (EHV-1) is a common pathogen of the horse which may induce mild respiratory distress, abortion, neonatal death and neurological disease. A single nucleotide polymorphism in the EHV-1 DNA polymerase (ORF30 A(2254) to G(2254)) has been associated with clinical signs of Equine herpes myeloencephalopathy (EHM). The aim of this work was to analyze the ORF30 genomic region among a panel of EHV-1 DNA extract in order to estimate the prevalence of the EHV-1 neuropathogenic genotype in France. Samples coming from cases associated with EHM, horses with respiratory symptoms and abort...
Wagner B, Burton A, Ainsworth D.Cytokines produced by T helper (Th) cells are important in orchestrating the immune response during health and disease. Recent reports indicated that cytokine mRNA expression in foals is often quantitatively lower than that of adult horses suggesting that foal T cells are not fully mature. Here, peripheral blood mononuclear cells from foals and adult horses were stimulated with phorbol 12-myristate 13-acetate and analyzed for intracellular interferon-gamma (IFN-gamma), interleukin-4 (IL-4) and IL-10 production, representing the Th1, Th2 and regulatory TR1 cell phenotypes respectively, by flow ...
Morrell JM, Rodriguez-Martinez H, Johannisson A.This study compared the effect on semen quality of different handling methods used in the preparation of stallion semen doses for artificial insemination. The three methods were (i) extending the ejaculate to 30-50 x 10(6)/ml, (ii) single layer centrifugation (SLC) and (iii) sperm washing (centrifugation without a colloid). An additional treatment was to add seminal plasma (SP) in various proportions to some SLC preparations. The resulting samples were evaluated for sperm motility by computer assisted sperm analysis, membrane integrity using the Nucleocounter SP-100 and chromatin integrity by ...
Scarth JP, Clarke AD, Teale P, Pearce CM.Effective detection of the abuse of androgenic-anabolic steroids in human and animal sports often requires knowledge of the drug's metabolism in order to target appropriate urinary metabolites. 'Designer' steroids are problematic since it is difficult to obtain ethical approval for in vivo metabolism studies due to a lack of a toxicological profile. In this study, the in vitro metabolism of estra-4,9-diene-3,17-dione is reported for the first time. This is also the first study comparing the metabolism of a designer steroid in the three major species subject to sport's doping control; namely th...
Liu M, Lei B.The secreted Mac protein made by group A Streptococcus (GAS) inhibits opsonophagocytosis of GAS by human polymorphonuclear leukocytes (PMNs). This protein also has the endopeptidase activity against human immunoglobulin G (IgG), and the Cys94, His262 and Asp284 are critical for the enzymatic activity. The horse pathogen Streptococcus equi subspecies equi produces a homologue of Mac (SeMac). SeMac was characterized to determine whether SeMac has IgG endopeptidase activity and inhibits opsonophagocytosis of S. equi by horse PMNs. The gene was cloned and recombinant SeMac was overexpressed in Esc...
Bouwman FG, van Ginneken MM, van der Kolk JH, van Breda E, Mariman EC.The aim of the study was to identify new biomarkers for acute tying-up in horses. Skeletal muscle biopsies were taken from 3 horses suffering from acute tying-up and 3 healthy horses. We performed 2D gel electrophoresis and mass spectrometry for identification of proteins that are differentially expressed in tying-up. 2D gel electrophoresis of skeletal muscle sequential extracts yielded more than 350 protein spots on each gel, of which 14 were differentially expressed more than two-fold (p<0.05). In-gel digestion followed by peptide mass fingerprinting enabled identification of three significa...
Ohta M, Wakuno A, Okada J, Kodaira K, Nagata S, Ito M, Oku K.To evaluate the effects of IV fentanyl administration on the end-tidal sevoflurane concentration (ET(SEVO)) in thoroughbred racehorses, the ET(SEVO) required for internal fixation of longitudinal fractures was compared between horses anesthetized with sevoflurane-fentanyl (Group SF; n=9) and those anesthetized with sevoflurane alone (Group S; n=9). The loading dose of fentanyl (5.0 µg/kg) was administered over 15 min followed by a maintenance dose of fentanyl (0.1 µg/kg/min) throughout the operation in Group SF. The mean ET(SEVO) during the operation in Group SF (2.6 ± 0.2%) was significant...
Lettry V, Kawasaki H, Sugaya K, Hosoya K, Takagi S, Okumura M.This study aimed to evaluate a system that identifies cartilage turn over and/or degradation through measurement of a new keratan sulfate (KS) epitope concentration in equine sera. Blood samples were collected from 30 horses, 1 (n = 15) and 2 year-olds (n = 15). Serum samples were analyzed for an epitope of keratan sulfate by 1/20/5D4 (KS5D4) and new epitopes of keratan sulfate using high sensitive keratan sulfate (HSKS), measured by two respective enzyme-linked immunosorbant assays (ELISAs). There was no correlation in serum concentration of KS evaluated using 5D4 and HSKS. Age had no signifi...
Kawcak CE, McIlwraith CW, Firth EC.To determine the effects of exercise at an early age on tissues in the metacarpophalangeal joints of horses. Methods: Twelve 18-month-old horses. Methods: All horses were pasture reared, but 6 horses had additional exercise starting at 3 weeks of age until 18 months of age. At that time, computed tomography, articular cartilage metabolism evaluation, and histologic assessments of synovial membrane, articular cartilage, and subchondral bone were performed. Results: Exercised horses had fewer gross lesions, less articular cartilage matrix staining in the dorsal aspect of the condyle, greater bon...
Ahmed MO, Clegg PD, Williams NJ, Baptiste KE, Bennett M.Escherichia coli isolates of equine faecal origin were investigated for antibiotic resistance, resistance genes and their ability to perform horizontal transfer. Methods: In total, 264 faecal samples were collected from 138 horses in hospital and community livery premises in northwest England, yielding 296 resistant E. coli isolates. Isolates were tested for susceptibility to antimicrobial drugs by disc diffusion and agar dilution methods in order to determine minimum inhibitory concentrations (MIC). PCR amplification was used to detect genes conferring resistance to: ampicillin (TEM and SHV b...
Lettry V, Sumie Y, Mitsuda K, Tagami M, Hosoya K, Takagi S, Okumura M.The objective of this study was to investigate the changes in synovial fluid concentration of collagen type II cleavage site (C2C) and procollagen II C-propeptide (CPII), markers of joint cartilage degeneration and synthesis, respectively, in horses with intraarticular fracture or osteochondrosis dissecans (OCD), and to examine the relationship between arthroscopic findings and these biomarker levels. Synovial fluid was collected from 36 joints in 18 horses (6 fractures and 12 OCDs). Samples from contralateral normal joints, when available, served as controls (n = 12). Concentrations of C2C an...
Sasaki N, Takakuwa J, Yamada H, Mori R.To evaluate effectiveness of allogeneic bone screws and pins for internal fixation of midbody transverse fractures of equine proximal sesamoid bones (PSBs) in vitro. Methods: 14 forelimbs from cadavers of 3-year-old Thoroughbreds. Methods: Allogeneic cortical bone fragments were collected from the limbs of a male Thoroughbred, and cortical bone screws were prepared from the tissue by use of a precision desktop microlathe programmed with the dimensions of a metal cortical bone screw. A midbody transverse osteotomy of each PSB was performed by use of a bone-shaping oscillating saw and repaired v...
Saulez MN, Godfroid J, Bosman A, Stiltner JL, Breathnach CC, Horohov DW.To determine concentrations of cytokine mRNA in horses with exercise-induced pulmonary hemorrhage (EIPH) after racing. Methods: 97 Thoroughbreds. Methods: Following tracheobronchoscopy, the severity of EIPH was graded (scale of 0 to 4), and venous blood samples were collected from 10 horses in each grade. After RNA isolation and cDNA synthesis, real-time PCR assay was conducted to detect cytokinespecific mRNA for interleukin (IL)-1, IL-6, and IL-10; interferon (INF)-gamma; and tumor necrosis factor (TNF)-alpha. Results: Neither location nor grade of EIPH affected the expression of IL-1 and INF...
Atta EH, Dias DS, Marra VL, de Azevedo AM.The best antithymocyte globulin preparation for first-line immune suppression in patients with severe aplastic anemia is still not clear. The aim of this study was to compare hematological response and overall survival in patients submitted to horse or rabbit antithymocyte globulin as first-line treatment for severe aplastic anemia. We retrospectively compared 71 consecutive patients with severe aplastic anemia, classified according to the antithymocyte globulin preparation. Analyses included variables related to patients and to immune suppression. Forty two patients (59.1%) received horse and...
Christmann U, Hite RD, Tan RH, Thatcher CD, Witonsky SG, Werre SR, Buechner-Maxwell VA.To evaluate the phospholipid composition and function of surfactant in horses with recurrent airway obstruction (RAO) at various clinical stages and compare these properties with findings in horses without RAO. Methods: 7 horses with confirmed RAO and 7 without RAO (non-RAO horses). Methods: Pairs of RAO-affected and non-RAO horses were evaluated before, during, and after exposure to hay. Evaluations included clinical scoring, lung function testing, airway endoscopy, and bronchoalveolar lavage fluid (BALF) absolute and differential cell counts. Cell-free BALF was separated into crude surfactan...
Olive J, d'Anjou MA, Alexander K, Beauchamp G, Theoret CL.To evaluate the ability of signal attenuation-based quantitative magnetic resonance imaging (QMRI) to estimate subchondral bone mineral density (BMD) as assessed via quantitative computed tomography (QCT) in osteoarthritic joints of horses. Methods: 20 metacarpophalangeal joints from 10 horse cadavers. Methods: Magnetic resonance (MR) images (dorsal and transverse T1-weighted gradient recalled echo [GRE] and dorsal T2*-weighted GRE fast imaging employing steady-state acquisition [T2*-FIESTA]) and transverse single-slice computed tomographic (CT) images of the joints were acquired. Magnetic res...
Niedermaier G, Poth T, Gehlen H.Two warmblood horses with a history of chronic weight loss and inappetence were referred to the Faculty of Veterinary Medicine, Ludwig-Maximilians University of Munich, Germany, for further examination. The clinical signs in horse 1 were fever, tachycardia and tachypnoea, and chronic ulcerative keratopathy of both eyes. Horse 2 had severe oral ulcerations and was coughing during feeding. In both horses, increased bronchovesicular sounds were heard during auscultation of the lungs. Laboratory findings included mild anaemia, lymphopenia and hypoalbuminaemia. Radiographic examination of the thora...
Groppelli E, Tuthill TJ, Rowlands DJ.Equine rhinitis A virus (ERAV) is genetically closely related to foot-and-mouth disease virus (FMDV), and both are now classified within the genus Aphthovirus of the family Picornaviridae. For disease security reasons, FMDV can be handled only in high-containment facilities, but these constraints do not apply to ERAV, making it an attractive alternative for the study of aphthovirus biology. Here, we show, using immunofluorescence, pharmacological agents, and dominant negative inhibitors, that ERAV entry occurs (as for FMDV) via clathrin-mediated endocytosis and acidification of early endosomes...
Venugopal CS, Mendes LC, Peiró JR, Laborde SS, Stokes AM, Moore RM.To identify differentially expressed genes in pulmonary tissues of horses affected with summer pasture-associated obstructive pulmonary disease (SPAOPD), which is a form of recurrent airway obstruction (RAO), compared with those of unaffected horses. Methods: 6 horses with SPAOPD-RAO and 6 unaffected (healthy) horses. Methods: Horses were assigned to 2 groups on the basis of medical history, clinical score, and transpleural pressure. Total RNA from each of the 5 lung lobes of each of the 6 SPAOPD-RAO-affected horses was extracted and pooled. Similarly, total RNA from unaffected horses was pool...
Medina-Torres CE, Weese JS, Staempfli HR.Clostridium difficile infection (CDI) is a recognized cause of colitis in the horse. Identification of its toxins is important for management of individual cases and for prevention of transmission and zoonosis. In humans, CDI diagnosis is performed with enzyme immunoassays, none of which have been validated for horses. Objective: (1) Establish which test for CDI diagnosis was more frequently used by diagnostic laboratories, (2) determine the identified test's performance, sensitivity, and specificity, and (3) validate its use in diarrheic horses. Methods: Samples were obtained from 72 horses p...
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...
Ikeda Y, Ishihara A, Nakajima M, Yamada K.Thoroughbred racehorses are commonly affected with superficial digital flexor (SDF) tendinopathy. This study aimed to identify risk factors for SDF tendinopathy in racing horses. The authors selected racehorses (n=292) with SDF tendinopathy from the medical records of a racetrack. As a risk factor associated with track-related variables, the SDF tendinopathy odds ratio (OR) was significantly high for a sloppy track surface compared with a standard track surface. Regarding risk factors associated with race-related variables, the SDF tendinopathy OR was significantly high in the following cases:...
Butler KD, Hintz HF.A pelleted ration was fed limited or ad libitum to two groups of seven Shetland 8-month-old ponies for 117 days. During the last 56 days, gelatin was added to the diets of four animals in each of the two intake groups. Gelatin was added at levels of 30 and 90 g per 100 kg body weight for the first and second 28-day periods, respectively.
Ponies fed the diet ad libitum consumed 180% more feed, had 50% greater rate of hoof growth (.384 ± .009 vs .254 ± .008 mm/d), 200% greater increase in height at the withers and 425% greater increase in body weight than ponies fed the limited level. The h...
Donkey placenta does not allow the passage of immunoglobulins; thus, foals are born hypogammaglobulinemic and an adequate intake of high-quality colostrum in the first 24 hours of life is crucial for the surviving. The study aims to assess the relation between colostrum immunoglobulin G (IgG) concentration evaluated by the single radial immunodiffusion (SRID) test and the Brix refractometer in donkeys to establish a cutoff value for high quality of colostrum based on Brix refractometry. Colostrum was collected at foaling, and at 6, 12, and 24 hours after foaling from the left and the right h...
Lyons ET, Drudge JH, Tolliver SC.Ivermectin paste formulation (200 micrograms/kg) was administered orally to 27 horses (13 Thoroughbreds and 14 of mixed breeding) to evaluate activity against adult Onchocerca spp in the ligamentum nuchae. Ages, known or estimated, of the horses ranged from 1 to 22 years. Single or multiple doses (1 to 5) of the drug were given to each horse. When multiple doses were administered, the intervals between treatments ranged from 7 to 92 days. At 27 to 171 days after initial treatment (single dose or first of multiple doses), the horses were killed. Some of the horses treated more than once were ki...
Ekmann A, Rigdal ML, Gröndahl G.Microscopy is usually used to obtain manual total and differential cell counts in equine synovial fluid. A faster, more precise method is desirable. Objective: The objectives were to compare an automated impedance method with a manual method for obtaining total and differential cell counts in equine synovial fluid and to evaluate the effect of pretreatment with hyaluronidase on automated results. Methods: Synovial fluid samples (n=48) were collected into EDTA and analyzed within 48 hours. Automated total and differential cell counts were evaluated using a Medonic CA620-VET hematology analyzer ...
Ogbourne CP.Studies on the epidemiology of Strongylus vulgaris infection of the
horse. International Journalfor Parasitology 5: 423426. Observations are reported on the size and age
structure of Stronglyus vulguris populations recovered from the anterior mesenteric artery and its
main branches of horses slaughtered at regular intervals throughout a year. Marked seasonal variations were found in the mean monthly numbers of worms present. During spring/early summer the
numbers were relatively low and a large proportion of the arteries had no worms in them at all.
Thereafter, the arterial worm burdens q...
Freestone JF, Thomas WP, Carlson GP, Brumbaugh GW.Pericarditis and pericardial effusion are considered to occur rarely in the horse. The clinical and laboratory features of idiopathic pericarditis with effusion diagnosed in 10 horses over a seven-year period were reviewed. Consistent physical findings included tachycardia, ventral oedema, jugular venous distention and diminished heart sounds. Electrocardiographic features included diminished voltages and electrical alternans, and the effusion was identified by echocardiography in the six horses in which it was performed. Pericardiocentesis relieved clinical signs in nine horses. Laboratory an...
Nagy A, Bodó G, Dyson SJ.There is limited information on potential diffusion of local anaesthetic solution after various diagnostic analgesic techniques of the proximal metacarpal region. Objective: To document potential distribution of local anaesthetic solution following 4 techniques used for diagnostic analgesia of the proximal metacarpal region. Methods: Radiodense contrast medium was injected around the lateral palmar or medial and lateral palmar metacarpal nerves in 8 mature horses, using 4 different techniques. Radiographs were obtained 0, 10 and 20 min after injection and were analysed subjectively. A mixture ...
Goncalves GR, Morotti F, Colombo AHB, Bonato DV, Bizarro-Silva C, Rosa CO, Cavalieri FLB, Seneda MM.Age and antral follicle count (AFC) are related to fertility in cattle, but this information remains limited in mares. Methods: To verify the influence of age and AFC on the reproductive characteristics of mares, 15 Quarter Horse donors, with 5-15 antral follicles, ranging from three to 17 years old, healthy and in good nutritional status, were divided into groups with low AFC (≤9 follicles) or high AFC (≥10 follicles) and mares considered young (≤9 years) or old (≥10 years). Mares were submitted to ultrasonography to determine the dominant follicle diameter, follicular growth rate, de...
Matthews A, Gilger BC.Equine immune mediated keratopathies are common in both Europe and the USA. This review article will compare the clinical differences in horses with this disease and also review the current theories on pathogenesis and treatment of equine IMMK.
Ollivier FJ.The precorneal tear film (PTF) is of critical importance in the physiologic and pathologic findings of the cornea. Clinicians should recall that quantitative and qualitative disorders of the PTF can be a cause of corneal diseases as well as a clinical sign of ocular surface diseases. It is also important to consider that some systemic and topical treatments may affect the PTF volume and composition. Not all interactions are known at this time. There is a continued need for basic research into PTF components in healthy and diseased equine eyes, because much remains unknown. Until additional bas...
Neuvonen E, Estola T.A serological survey on the occurrence of group-specific chlamydial antibodies in random sera of Finnish sheep, cattle and horses was performed. The whole material consisted of 1347 serum samples, including 432 ovine, 454 bovine and 461 equine sera. The sera were sent to the laboratory for various serological tests during 1968–1972. Of the ovine sera 9.5%, bovine 12.8 % and equine 7.1 % showed a titer ≥ 1:16 in the complement fixation test. No definite geographic differences could be found in the distribution of the herds which showed positive results. The ubiquity of chlamydial infections...
Bockisch F, Aboling S, Coenen M, Vervuert I.Vitamin-D intoxication by yellow oat grass is often reported under the syndrome of enzootic calcinosis in ruminants in the upper regions of the Alps. The intake of Trisetum flavescens in ruminants and horses induces calcification of soft tissue, including vessels, tendons and ligaments, lung, heart and kidneys. Clinical symptoms, including a reluctance to move, inappetence, body-weight loss and impaired organ function, are frequently observed. To date, there are only a very few case reports about yellow-oat-grass intoxication in horses. The present case report describes Vitamin-D intoxication ...
Ishii M, Kobayashi S, Acosta TJ, Miki W, Matsui M, Yamanoi T, Miyake Y, Miyamoto A.The aim of this study was to establish the effectiveness of administration of oxytocin (OT) on placental expulsion after foaling. Four foaling mares with the placentas retained for up 1 hr after foaling received OT (50 IU) administration at 1 hr intervals before expulsion of the placenta. The changes in the plasma concentrations of OT and the PGF2alpha metabolite (PGFM) were investigated, and the influence of OT administration was considered. The results were as follows. The placenta was expelled after one to three OT administrations in all four mares that received OT. In two mares, which expe...
Gastal EL, Bergfelt DR, Nogueira GP, Gastal MO, Ginther OJ.The effects of several doses of progesterone on FSH and LH concentrations were used to study the role of the gonadotropins on deviation in growth rates of the two largest follicles during the establishment of follicle dominance. Progesterone was given to pony mares at a daily dose rate of 0 mg (controls), 30 mg (low dose), 100 mg (intermediate dose), and 300 mg (high dose). All follicles > or = 6 mm were ablated at Day 10 (Day 0 = ovulation) to initiate a new follicular wave; prostaglandin F(2alpha) was given to induce luteolysis, and progesterone was given from Days 10 to 24. The low dose ...
Gibson MJ, Bolwell CF, Gee EK, Legg KA, Rogers CW.The objective of this study was to describe the incident and non-incident reports of Thoroughbred flat racing in New Zealand. Retrospective stipendiary stewards' reports of race day events during the 2015/2016 and 2016/2017 racing season were examined. The primary injury and reporting outcomes were analysed to assess the horse- and race-level risk factors associated with the occurrence of incident and non-incident reports. The number of incident and non-incident events and binomial exact 95% confidence intervals were calculated per 1000 horse starts. Most reports were for non-incidents and exa...
Bailey M, Lloyd S, Martin SC, Soulsby EJ.Proliferation in vitro of peripheral blood lymphocytes both from horses infected with Strongylus vulgaris and from helminth-free ponies was observed in the presence of extracts of the fourth and fifth stage larvae and adults of S. vulgaris. In addition, S. vulgaris extracts induced transformation in cultures of peripheral blood lymphocytes from sheep and dogs and in mouse spleen cell cultures. Nylon wool non-adherent, T cell enriched fractions of lymphocytes from both mice and horses were stimulated by the S. vulgaris larval mitogen while no proliferation was observed in cultures containing ny...
Desjardin C, Riviere J, Vaiman A, Morgenthaler C, Diribarne M, Zivy M, Robert C, Le Moyec L, Wimel L, Lepage O, Jacques C, Cribiu E, Schibler L.Osteochondrosis (OC(D)) is a juvenile osteo-articular disorder affecting several mammalian species. In horses, OC(D) is considered as a multifactorial disease and has been described as a focal disruption of endochondral ossification leading to the development of osteoarticular lesions. Nevertheless, OC(D) physiopathology is poorly understood. Affected horses may present joint swelling, stiffness and lameness. Thus, OC(D) is a major concern for the equine industry. Our study was designed as an integrative approach using omics technologies for the identification of constitutive defects in epiphy...
Kim J, Jung H, Yoon M.Dopamine (DA) is a neurotransmitter associated with animal behaviors. Along with other neurotransmitters such as oxytocin (OXT) and serotonin (5-HT), DA is also involved in determining the temperament of animals. However, the involvement of DA in horse temperament has not been well elucidated. Therefore, in this study, we aimed to determine the correlation between plasma DA concentration and OXT and 5-HT concentrations and behavioral temperament (eg, docility and friendliness, fearfulness, dominance, and trainability) of horses. Blood samples were collected from 31 horses and the concentration...
Sinding MF, Berg LC.The aetiological factors behind impinged or overriding of dorsal spinous processes ('kissing spine syndrome', KSS) are not clearly understood. Back conformation, breed, age, training and gender may play important roles in this condition. Radiographic changes vary and abnormalities are seen in many clinically normal horses, but the conclusion of previous studies in mature horses is that interspinous spaces <4 mm are considered too narrow and potentially indicative of KSS. Objective: To evaluate whether narrowing of the interspinous space was present in a population of normal Warmblood foals....
Dubuc V, Lepault E, Theoret CL.Wound repair in horse limbs is often complicated by excessive fibroplasia and scarring. Occlusion of the microvessels populating the granulation tissue appears to be involved in the excessive accumulation of extracellular matrix during the repair of limb wounds. This study aimed to determine whether endothelial cell hypertrophy or hyperplasia, or both, contribute to microvascular occlusion and whether the pericyte is involved in this anomaly. We created 5 wounds, each 2.5 x 2.5 cm, on both forelimbs and on the body of 6 horses. One limb was bandaged to stimulate excessive wound fibroplasia. We...
Hopster K, Wittenberg-Voges L, Geburek F, Hopster-Iversen C, Kästner SBR.Aim of this prospective experimental study was to assess effects of systemic hypoxemia and hypovolemia on global and gastrointestinal oxygenation and perfusion in anesthetized horses. Therefore, we anesthetized twelve systemically healthy warmblood horses using either xylazine or dexmedetomidine for premedication and midazolam and ketamine for induction. Anesthesia was maintained using isoflurane in oxygen with either xylazine or dexmedetomidine and horses were ventilated to normocapnia. During part A arterial oxygen saturation (SaO) was reduced by reducing inspiratory oxygen fraction in steps...
Donaldson LL, Trostle SS, White NA.The use of laparoscopy for the diagnosis or therapeutic management of abdominal disease in the horse has distinct advantages when it allows the horse to remain standing. However, distending the abdomen by insufflation of a biologically active gas in an anaesthetised horse may add to the physiological challenge of general anaesthesia and recumbency. The cardiopulmonary responses to abdominal insufflation with carbon dioxide (CO2) to 15 mmHg pressure were evaluated in 6 horses in dorsal recumbency anaesthetised with halothane in oxygen and subjected to laparoscopic colopexy. Vaporiser settings t...
Griffin C.Postpartum evaluation of the foal's head and mouth are performed to detect craniofacial malformations and other congenital defects. Detailed oral examination and diagnostic imaging can provide diagnostic and prognostic information about congenital abnormalities of the mouth or skull. Important abnormalities of foals include wry nose, cleft palate, overbite (parrot mouth), and underbite (monkey mouth, sow mouth). Tumors and cysts can be detected in young horses. In juvenile horses, primary dental care procedures include oral examination, management of sharp enamel points, management of deciduou...
Claerhoudt S, Bergman HJ, Van Der Veen H, Duchateau L, Raes EV, Saunders JH.Distal border synovial invaginations of the distal sesamoid bone are radiographically assessed during the selection process of horses admitted as breeding stallions or in purchase examinations. Nowadays, many moderately or some deeply penetrating proximally enlarged synovial invaginations are considered as moderate or severe radiographic findings. Objective: To measure the difference between and agreement of the morphology of distal border synovial invaginations on radiography vs. computed tomography (CT). It was hypothesised that the morphology of distal border synovial invaginations would be...
Sanchez LC, Lester GD, Merritt AM.To determine intragastric pH in newborn foals and to examine the effect of i.v. or oral administration of an H2-receptor antagonist on intragastric pH. Methods: Prospective controlled study. Methods: 6 healthy mixed-breed neonatal foals. Methods: Intragastric pH was measured, using an antimony electrode. Foals were monitored on days 2, 4, and 6 after birth, and each received 3 treatments. The pH was recorded for 4 hours before treatment and for 10 hours after ranitidine administration (2 mg/kg [0.91 mg/lb] of body weight, i.v.; 6.6 mg/kg [3 mg/lb], PO) or 20 hours after corn syrup administrati...
Takeuchi T, Sugita S.A cytoarchitectural classification of the horse cerebral cortex was done to determine whether functional locations exist or not such as found in the human cerebral cortex. Two adult horse brains were examined by Nissl and myelin stained methods. Six cell layers of the cerebral cortex were identified and classified into five types areas based on the cytoarchitectural organization: agranular, frontal, parietal, polar and granulous types. The agranular type was seen around the gyrus sylvius. In layer V of the agranular type, there were the many large cells that seemed like Betz cells. This type w...
Vilar JM, Santana A, Espinosa J, Spinella G.The assessment of a normal range for cross-sectional area (CSA) of tendons in the tarsal region is important in order to use them as reference values in the identification of pathological changes of dimensions. Objective: To provide normal reference values for the CSA of the tendons of the tarsus of Standardbred trotter horses (STH) by means of ultrasonography. Methods: Transverse echographic images of the tendons were obtained at different levels proximodistally; these images were digitised and CSA values (mean ± s.d.) were obtained for each structure. Results: The largest structure correspo...
