"Horses" is a broad topic that encompasses various aspects of equine biology, behavior, and management. This category includes studies on the anatomy, physiology, and genetics of horses, as well as their behavior, nutrition, and care. Research in this area may also cover the historical and cultural significance of horses, their roles in agriculture, sport, and therapy, and the challenges associated with their conservation and welfare. The page aggregates peer-reviewed research articles and scholarly studies that explore the multifaceted relationships between humans and horses, examining both scientific and socio-economic perspectives.
Loroño-Pino MA, Blitvich BJ, Farfán-Ale JA, Puerto FI, Blanco JM, Marlenee NL, Rosado-Paredes EP, García-Rejón JE, Gubler DJ, Calisher CH....Serum samples were obtained from 252 horses in the State of Yucatan, Mexico, from July to October 2002. Antibodies to West Nile virus were detected by epitope-blocking enzyme-linked immunosorbent assays in three (1.2%) horses and confirmed by plaque reduction neutralization test. We report the first West Nile virus activity in the State of Yucatan.
Curtin DJ.An aggressive mare, presented for prebreeding examination, was found to have a significantly enlarged ovary (soccer ball size). A granulosa thecal cell tumor was initially suspected. Following laboratory and repeated clinical examination, the mare was diagnosed with an ovarian hematoma, which regressed with treatment.
Brown NA, Pandy MG, Kawcak CE, McIlwraith CW.A detailed musculoskeletal model of the distal equine forelimb was developed to study the influence of musculoskeletal geometry (i.e. muscle paths) and muscle physiology (i.e. force-length properties) on the force- and moment-generating capacities of muscles crossing the carpal and metacarpophalangeal joints. The distal forelimb skeleton was represented as a five degree-of-freedom kinematic linkage comprised of eight bones (humerus, radius and ulna combined, proximal carpus, distal carpus, metacarpus, proximal phalanx, intermediate phalanx and distal phalanx) and seven joints (elbow, radiocarp...
López-Sanromán J, Cruz J, Santos M, Mazzini R, Tabanera A, Tendillo FJ.The objective of this study was to determine the effects of the alkalinization on the local analgesic efficacy of 1% ketamine in the abaxial sesamoid nerve block in horses. Thirty-six mature healthy horses were randomly assigned to four groups for the following treatments; an abaxial sesamoid block with 5 mL of saline solution (control saline); an abaxial sesamoid block with 5 mL of a solution containing 1% ketamine (KETs 1%); an abaxial sesamoid block with 5 mL of a solution containing saline solution and 0.5 mEq of sodium bicarbonate (control bicarbonate); and an abaxial sesamoid block with ...
Pérez R, Godoy C, Palma C, Cabezas I, Muñoz L, Rubilar L, Arboix M, Alvinerie M.A study was undertaken in order to evaluate and compare ivermectin's (IVM) plasma disposition kinetic parameters after oral or intramuscular (IM) administration in horses. Ten clinically healthy adult horses, weighing 380-496 kg body weight (BW), were allocated to two experimental groups of five horses. Group I, was treated with an oral paste formulation of IVM at the manufacturer's recommended dose of 0.2 mg/kg BW. Group II, was treated IM with an injectable 1% formulation of IVM at a dose of 0.2 mg/kg BW. Blood samples were collected by jugular puncture at different times between 0.5 h and 7...
Saint-Dizier M, Chopineau M, Dupont J, Daels PF, Combarnous Y.Luteal steroids are necessary to maintain the first 70-90 days of pregnancy in the mare. At 35 days postovulation, the resurgence of the primary corpus luteum (CL) coincides with the secretion of the fetal hormone eCG. In order to study the responsiveness of the primary CL to eCG, we have examined levels of luteal equine LH/CG receptors (eLH/CG-R) mRNAs by Northern blot analysis and measured concentrations of eLH/CG binding sites on luteal membranes using 125I-eLH saturation binding assays at three stages of gestation: before the onset of eCG secretion (Days 14-31), from onset to maximum eCG s...
Pape M, Posedi J, Failing K, Schnieder T, von Samson-Himmelstjerna G.To study the prevalence of the polymorphism in position 200 of the beta-tubulin gene in the mechanism of benzimidazole (BZ) resistance in cyathostomes of horses, an allele-specific PCR was used to detect the genotype of individuals of BZ-susceptible and BZ-resistant populations. The molecular analysis of 100 adults recovered from an anthelmintic-naïve horse revealed 80% homozygous TTC/TTC individuals, 17% heterozygous TTC/TAC and 3% homozygous TAC/TAC. A naturally infected horse was treated with increasing fenbendazole (FBZ) dosages to select a BZ-resistant population of cyathostomes. The PCR...
Dixon RM, McGorum BC, Railton DI, Hawe C, Tremaine WH, Dacre K, McCann J.Laryngoplasty (LP) is currently the most common surgical treatment for equine laryngeal paralysis, however, there have been no reports quantifying the degree of retention of arytenoid abduction following LP. Additionally, the complications of LP have been poorly documented. Objective: To record the degree of arytenoid abduction retention following LP and to accurately document all complications of surgery. Methods: A study (1986-1998) of 200 horses of mixed breed and workload, median age 6 years (prospective 136 cases and retrospective 64 cases) undergoing LP (using 2 stainless steel wires) an...
Dixon PM, McGorum BC, Railton DI, Hawe C, Tremaine WH, Dacre K, McCann J.There is continuing debate on the clinical benefit of laryngoplasty (LP) in the treatment of equine laryngeal paralysis. In particular, there is little information available on the clinical value of this surgery in older horses, in non-Thoroughbreds or in sports or pleasure horses; nor on the relationship between the degree of LP abduction achieved and the clinical value of LP. Objective: To evaluate the owner's assessment of the value of LP (and combined ventriculocordectomy) in an older, mixed breed and mixed workload population of horses and to also assess the relationship between the degre...
Denoix JM, Thibaud D, Riccio B.Bisphosphonates, such as tiludronate, are used to normalise bone metabolism via inhibition of bone resorption. Areas of increased bone resorption and formation are typical lesions in a diseased navicular bone. Objective: To determine if bone remodelling changes occurring in navicular disease may be corrected with therapies regulating bone metabolism. Methods: We designed a double-blind, placebo-controlled clinical trial to compare 2 doses of tiludronate, 0.5 mg/kg and 1 mg/kg bwt administered via daily i.v. injections over 10 days for the treatment of navicular disease. Seventy-three horses, s...
McGowan CM, Neiger R.Trilostane, a competitive 3-beta hydroxysteroid dehydrogenase inhibitor, has been used successfully to control clinical signs and cortisol excess in canine pituitary dependent hyperadrenocorticism. Objective: Trilostane was evaluated for its efficacy in resolving clinical and clinicopathological abnormalities of equine Cushing's syndrome (ECS) and to assess its safety. Methods: Twenty horses (mean age 21 years) diagnosed with ECS were followed for 1 or 2 years. Affected horses received 0.4-1 mg/kg (mean 0.5 mg/kg) trilostane once daily. Results: Clinical signs assessed over 1 or 2 years, showe...
Ramzan PH, Newton JR, Shepherd MC, Head MJ.Tibial stress fractures are an important cause of lameness in the Thoroughbred racehorse. While it is recognised that these injuries can vary in clinical presentation and radiographic or scintigraphic appearance, little has been done to quantify lesion severity. By contrast the scintigraphic grading of tibial stress fractures in human athletes is widely reported and assists in the selection of appropriate management regimes. Objective: To determine the relationship between scintigraphic grade, clinical severity and radiographic appearance of tibial stress fractures. Methods: The current study ...
Picandet V, Léguillette R, Lavoie JP.Corticosteroids are currently the most effective drugs for the control of 'heaves' in horses. However, there is limited information concerning the comparative efficacy and tolerability of the various corticosteroids when used for treatment. Objective: To compare the therapeutic and side effects of isoflupredone acetate to those of dexamethasone. Methods: A parallel design to compare the effects of 2 corticosteroids by evaluating lung function, serum cortisol and electrolyte concentrations, response to ACTH stimulation and haematology sequentially during a 14 day control period (no treatment), ...
Walmsley JR, Phillips TJ, Townsend HG.There is little published information available describing clinical signs, arthroscopic findings and prognosis of meniscal injuries in horses. Objective: To evaluate the effect on the outcome not only of the arthroscopic findings and treatment, but also of the clinical and radiographic signs in these horses. Methods: The following were recorded for each case: the meniscal injury, graded according to severity; clinical and radiographic findings prior to surgery; any concurrent injury in the joint seen at arthroscopy. The effect of these factors and the grade of injury on the outcome were analys...
Bergadano A, Lauber R, Zbinden A, Schatzmann U, Moens Y.Blood/gas partition coefficients (lambda(b/g)) for volatile agents in horse blood are reported for halothane but not for isoflurane and sevoflurane. We measured the lambda(b/g) of halothane, isoflurane and sevoflurane in the blood of fasted horses. The correlation with age, weight and some haematological and biochemical variables was studied. The temperature correction factor for isoflurane solubility was calculated. Methods: Twenty-four horses were randomly allocated to halothane (n=8), isoflurane (n=8) or sevoflurane (n=8). Blood samples were taken after 10 h' fasting. Calculation of lambda(...
Båverud V, Gustafsson A, Franklin A, Aspán A, Gunnarsson A.Clostridium difficile has been associated with acute colitis in mature horses. Objective: To survey C. difficile colonisation of the alimentary tract with age, occurrence of diarrhoea and history of antibiotic therapy; and to study the occurrence and survival of C. difficile in the environment and antimicrobial susceptibility of isolated strains. Methods: A total of 777 horses of different breeds, age and sex were studied. Further, 598 soil samples and 434 indoor surface samples were examined. Antimicrobial susceptibility of 52 strains was investigated by Etest for 10 antibiotics. Results: In ...
Loretti AP, Colodel EM, Gimeno EJ, Driemeier D.This study reports a neurological disease unrecognised until now in ponies in southern Brazil. Objective: Epidemiological data strongly suggests that the ingestion of Sida carpinifolia is involved in the aetiology. We tested the hypothesis that it is an acquired lyosomal storage disease. Methods: Following the death of 3 ponies, all ponies from the premises were closely monitored; epidemiological data and clinical findings carefully recorded. Fragments of several organs, including CNS, were fixed in neutral formalin and embedded in paraffin-wax. Sections were stained with haematoxylin and eosi...
Feige K, Schwarzwald CC, Bombeli T.Unfractioned heparin (UFH) is widely used for prophylaxis of coagulation disorders, especially in colic-affected horses. However, it is accompanied by certain side effects. Objective: To compare the efficacy and side effects of unfractioned and low molecular weight heparin (LMWH) in horses with colic. Methods: The study was carried out as a randomised, double-blind, controlled clinical trial. Fifty-two horses with colic were treated subcutaneously with either UFH (heparin calcium, 150 iu/kg bwt initially, followed by 125 iu/kg bwt q. 12 h for 3 days and then 100 iu/kg bwt q. 12 h) or LMWH (dal...
Vengust M, Arroyo LG, Weese JS, Baird JD.Clostridial myonecrosis is caused by histotoxic or tissue-
destroying clostridia (Allen et al. 1999). Clostridium perfringens
and C. septicum are the most common isolates in horses, followed
by C. chauvoei, C. novyi and C. fallax (McLaughlin et al. 1979;
Westman et al. 1979; Hagemoser et al. 1980; Murphy 1980; Van
Heerden and Botha 1982; Coloe et al. 1983; Valberg and
McKinnon 1984; Rebhun et al. 1985; Perdrizet et al. 1987). The
disease is characterised by a rapid spread of tissue necrosis
combined with a lack of leucocyte infiltration at the site of
infection (Stevens et al. 1987). ...
Wilkins RJ, Fairfax TP, Davies ME, Muzyamba MC, Gibson JS.Ca2+ homeostasis in articular chondrocytes affects synthesis and degradation of the cartilage matrix, as well as other cellular functions, thereby contributing to joint integrity. Although it will be affected by mechanical loading, the sensitivity of intracellular Ca2+ concentration ([Ca2+]i) in equine articular chondrocytes to many stimuli remains unknown. Objective: An improved understanding of Ca2+ homeostasis in equine articular chondrocytes, and how it is altered during joint loading and pathology, will be important in understanding how joints respond to mechanical loads. Methods: [Ca2+]i...
Maxwell LK, Thomasy SM, Slovis N, Kollias-Baker C.Although fentanyl has been reported to cause CNS excitation in horses, a transdermal therapeutic system (TTS) containing this mu agonist has recently been used empirically in equine medicine to treat moderate to severe pain. A better understanding of the disposition of fentanyl following transdermal administration would facilitate the clinical use of TTS fentanyl to obtain analgesia in horses. Objective: To determine the pharmacokinetics of fentanyl following i.v. and TTS patch administration in healthy, mature horses and to evaluate the tolerance of horses to TTS fentanyl administration. Meth...
Schumacher J, Schumacher J, Gillette R, DeGraves F, Schramme M, Smith R, Perkins J, Coker M.Analgesia of the palmar digital (PD) nerves has been demonstrated to cause analgesia of the distal interphalangeal (DIP) joint as well as the sole. Because the PD nerves lie in close proximity to the navicular bursa, we suspected that that analgesia of the navicular bursa would anaesthetise the PD nerves, which would result in analgesia of the DIP joint. Objective: To determine the response of horses with pain in the DIP joint to instillation of local anaesthetic solution into the navicular bursa. Methods: Lameness was induced in 6 horses by creating painful synovitis in the DIP joint of one f...
Doherty TJ, Andrews FM, Blackford JT, Rohrbach BW, Sandin A, Saxton AM.Endotoxaemia causes a disruption of gastrointestinal motility in the horse but there is no information on its effects on gastric secretion. Lipopolysaccharide (LPS) administration is known to affect gastric secretion in other species. Objective: That LPS, a toxic component of Gram-negative bacteria, would reduce gastric acid secretion and that pretreatment with phenylbutazone (PBZ) would block the effects of LPS. Methods: The effects of LPS and PBZ on gastric contents were investigated in fasted, mature horses, with permanent gastric cannulae. Horses were pretreated with either saline or PBZ 1...
Cupp EW, Klingler K, Hassan HK, Viguers LM, Unnasch TR.A site near Tuskegee, Alabama was examined for vector activity of eastern equine encephalomyelitis (EEE) virus in 2001. More than 23,000 mosquitoes representing 8 genera and 34 species were collected during a 21-week period, and five species, Culiseta melanura, Aedes vexans, Coquillettidia perturbans, Culex erraticus, and Uranotaenia sapphirina, were examined for the presence of virus using a nested reverse transcriptase-polymerase chain reaction for EEE virus. Each species was infected at various times of the mosquito season (May-September) with different minimum infection rates (MIRs). Culis...
Frankeny RL.Five horses with unilateral epidermal inclusion cysts located in the nasal diverticula were sedated and treated with intralesional injection of neutral-buffered 10% formalin (volume range, 2 to 4.5 mL). After aspiration of the cyst, formalin was injected intralesionally until leakage of fluid around the needle was observed. After several weeks, desiccation of the cyst was evident; it was excised 2 weeks after treatment in 3 horses, digitally removed by the owner of 1 horse, and never removed in 1 horse, because the owner declined further treatment after resolution of the original swelling of t...
Daly JM, Yates RJ, Browse G, Swann Z, Newton JR, Jessett D, Davis-Poynter N, Mumford JA.Vaccination and challenge studies in ponies are the most relevant experimental system for predicting whether strains included in equine influenza vaccines are relevant, but they are difficult to perform. Objective: In order to investigate the feasibility of using a small animal model, results of a cross-protection study in hamsters were compared with those from a previous pony challenge experiment. Methods: Animals were immunised with inactivated vaccines containing one of 4 strains of equine influenza A H3N8 subtype virus isolated over a 26 year period (1963 to 1989), then challenged with a 1...
Dechant JE, Baxter GM, Frisbie DD, Trotter GW, McIlwraith CW.Osteoarthritis is a frequent sequela of joint disease, especially with severe injuries or if attempts at therapy are unsuccessful. Negative and positive effects of corticosteroid treatment of articular cartilage have been demonstrated by in vitro and in vivo studies. Objective: To assess the metabolic effects of varying dosages of methylprednisolone acetate (MPA) and triamcinolone acetonide (TA) on interleukin-1alpha (IL-1) conditioned equine cartilage explants. Our hypothesis was that lower dosages of corticosteroids would be less detrimental to cartilage metabolism than higher dosages. TA wo...
Gerber V, Robinson NE, Luethi S, Marti E, Wampfler B, Straub R.Horses housed in conventional stable environments are exposed to high dust loads. Long-term exposure to inhaled dust may lead to subclinical airway disease. Objective: Airway inflammation and mucus accumulation are 1) common in asymptomatic well-performing sport horses, 2) increased in older compared to younger individuals and 3) correlated. Methods: Mucus quantity and quality (endoscopic scoring) and BALF differential cytology were assessed in 13 younger horses (mean age 5 years) and 13 older horses (mean age 15 years), which had no historical or clinical evidence of lower airway disease, wer...
Rose RJ, Ilkiw JE, Hodgson D.Thirty-one horses competing in a 100 kilometre endurance ride had electrocardiograms recorded before and after the ride from which the heart score of each horse was calculated. Blood was also taken to determine the packed cell volume (PCV) and total plasma protein (TPP) before the ride, after 60 kilometres (mid ride) and at completion of the ride. Statistical analysis of the heart scores showed that a faster group of horses had significantly higher heart scores than either a slower group or those eliminated due to inadequate recovery of heart rate. No horses developed electrocardiogram abnorma...
Lavin TE, Nielsen BD, Zingsheim JN, O'Connor-Robison CI, Link JE, Hill GM, Shelton J.An experiment was conducted to study P digestibility in mature horses because of the growing environmental concerns regarding P runoff and previous equine research focused mostly on young and growing animals or used ponies as a model. Phytase supplementation of swine and poultry diets can result in greater phytate-P digestibility, leading to a decreased need for inorganic P supplementation and a decrease in P excreted to the environment; this, however, has not been demonstrated in the horse. Six mature Arabian geldings were fed 6 diets consisting of pelleted concentrate and alfalfa hay. The co...
Elemmawy YM, Senna NA, Abu-Seida AM, Youssef AF.Injury of suspensory ligament (SL) branch is a frequently diagnosed problem in horses of different ages and disciplines. This case reports for the first time the ultrasonography, computed tomography (CT), magnetic resonance imaging (MRI) findings in a 10-year-old draught horse with traumatic chronic SL branch desmitis of 8 months duration. The horse had a grade 3 of 5 left hindlimb lameness with a moderately hot, painful, and diffuse swelling from the tarsus till the hoof. Ultrasonography, both SL branches appeared as enlarged hyperechogenic structures with poor demarcation of their margins a...
Gómez MD, Goyache F, Molina A, Valera M.The mating policy for Spanish Purebred horses encourages the same or closely related stallions to be used for reproduction across studs differing in environments. Stallions may perform differently across studs, and if so, adjustment for the sire x stud (ss) interaction is recommended. However, there are no studies available that analyzed the influence of ss interaction on estimation of genetic parameters in horses. This research is aimed at assessing the implications of including ss interaction in models fitted for the estimation of genetic parameters for traits under selection using 8 body me...
Lokhorst HM, Breukink HJ.Two cases of Auto-immune hemolytic anemia (AHA) in the horse are described. The pathogenesis of AHA in man is related to the findings in the horses. Besides from routine hematological and biochemical investigations specific data were obtained from the erythrocyte osmotic fragility test, the Coombs test, the serum haptoglobulin level and the cold agglutinin test. The first patient, a six month old Dutch standardbred colt, probably suffered from an acute attack of cold-induced hemoglobinuria with severe anemia and acronecrosis of the tops of both ears and of several parts of the skin that had be...
Seiler GS, Campbell N, Nixon B, Tsuruta JK, Dayton PA, Jennings S, Redding WR, Lustgarten M.Vascular alterations play important roles in many orthopedic diseases such as osteoarthritis, tendonitis, and synovitis in both human and equine athletes. Understanding these alterations could enhance diagnosis, prognosis, and treatment. Contrast-enhanced ultrasound (CEUS) could be a valuable method for evaluation of blood flow and perfusion of these processes in the equine distal limb, however no reports were found describing feasibility or safety of the technique. The goal of this prospective, experimental study was to describe the feasibility and safety of distal limb CEUS in a sample of si...
Dabareiner RM, Carter GK, Honnas CM.To determine history, clinical and radiographic abnormalities, and outcome in horses with signs of navicular area pain unresponsive to corrective shoeing and systemic nonsteroidal anti-inflammatory drug administration that were treated with an injection of corticosteroids, sodium hyaluronate, and amikacin into the navicular bursa. Methods: Retrospective study. Methods: 25 horses. Methods: Data collected from the medical records included signalment, history, horse use, severity and duration of lameness, shoeing regimen, results of diagnostic anesthesia, radiographic abnormalities, and outcome. ...
McClure JT.Leukoproliferative disorders reported in horses include lymphoma, lymphocytic leukemia, plasma cell myeloma, granulocytic leukemia, monocytic leukemia, myelomonocytic leukemia, and eosinophilic leukemia. Lymphoma affects horses of all ages, whereas leukemias often occur in younger horses. Clinical signs are often nonspecific including depression, anorexia, fever, and weight loss. Specialized diagnostic techniques such as cytochemistry and immunophenotyping better define the cellular origin of leukoproliferative disorders, which is essential for developing appropriate therapeutic protocols and ...
Wong DM, Hepworth-Warren KL, Sponseller BT, Howard JM, Wang C.OBJECTIVE To assess multiple central venous and arterial blood variables that alone or in conjunction with one another reflect global oxygenation status in healthy neonatal foals. ANIMALS 11 healthy neonatal foals. PROCEDURES Central venous and arterial blood samples were collected from healthy neonatal foals at 12, 24, 36, 48, 72, and 96 hours after birth. Variables measured from central venous and arterial blood samples included oxygen saturation of hemoglobin, partial pressure of oxygen, lactate concentration, partial pressure of carbon dioxide, and pH. Calculated variables included venous-...
McKenzie EC, Valberg SJ, Godden SM, Pagan JD, Carlson GP, MacLeay JM, DeLaCorte FD.To determine whether plasma, urine, and fecal electrolyte and mineral concentrations differ between clinically normal horses and Thoroughbreds with recurrent exertional rhabdomyolysis (RER) after consumption of diets varying in cation-anion balance. Methods: 5 Thoroughbred mares with RER and 6 clinically normal mixed-breed mares. Methods: Each of 3 isocaloric diets designated as low, medium, and high on the basis of dietary cation-anion balance (DCAB) values of 85, 190, and 380, respectively, were fed to horses for 14 days. During the last 72 hours, 3 horses with RER and 3 control horses had d...
Lamb L, Zubrod C, Hague B, Brakenhoff J, Major M.The significance of collateral ligament desmitis of the tarsocrural joint is often clinically underestimated, because it is an uncommon injury with a guarded prognosis for athletic soundness. The objective of this study was to describe the clinical presentation, treatment, and outcome of 12 horses with collateral ligament desmitis, along with tarsocrural joint synovitis secondary to hemarthrosis. Criteria for inclusion in this study included clinical signs of tarsocrural joint synovitis and sonographic evidence of collateral ligament desmitis. This retrospective study evaluated horses over an ...
Keg PR, van Weeren PR, Back W, Barneveld A.The influence of the force applied and its period of application on the outcome of the flexion test of the distal forelimb was investigated in a group of eight sound horses. The degree of lameness after the flexion test was scored by a standard clinical classification, and by measuring the angle of maximum fetlock extension by means of the infrared light-based MacReflex gait analysis system. There was a good correlation between the clinical score and this electronically recorded kinematic parameter (r = 0.96). Both the force applied and the period of application affected the outcome of the tes...
Gáspárdy A, Rieden S, Simonyi Z, Szemere B, Bodó I.The authors give a short orientation about the age related parameters of the incisors based on the literature. They examined the question of breed differences with respect to the age determination of horses in the different counties, especially in regard to the English Thoroughbred. In this context they present a new parameter as well as a new approach in data-processing. The cup depth and the yearly abrasion showed high breed-specificity. The relative abrasion indicated that the most intensive wear out is typical for the Thoroughbred. The cup depth and the yearly wear out were different accor...
Robertson SA, Steele CJ, Chen CL.The effect of general anaesthesia and arthroscopic surgery on blood glucose and lactate, plasma non-esterified fatty acids, insulin, beta-endorphin and cortisol was investigated in seven horses. Animals were premedicated with xylazine and anaesthesia was induced with guaifenesin and sodium thiamylal and maintained with halothane vaporised in oxygen. Blood samples were collected in the pre-, intra- and post operative period. Induction of anaesthesia was associated with a transient hyperglycaemia and a significant rise in plasma insulin levels. Plasma insulin values fell during surgery but showe...
Allbaugh RA, Keil SM, Ou Z, Bello NM.To assess intraocular pressure (IOP) in conditioned equine athletes and document changes with exercise. A secondary objective was to assess associations between IOP and heart rate, as well as with other subjective physical parameters. Methods: Horses were evaluated during 50 mile endurance ride competitions. Data were collected on 69 horses during five different competitions at three different locations with 59 horses ridden once, nine horses ridden in two competitions, and one horse ridden in three competitions for a total of 80 horse-ride combinations. Methods: Intraocular pressure was measu...
Cesarini C, Macieira S, Girard C, Drolet R, d'Anjou MA, Jean D.The costochondral junction constitutes a potential site of infection in septic foals and it could be favored by thoracic trauma. Standard radiographs and ultrasonography are useful tools for diagnosis of this condition and ultrasound-guided needle aspiration could permit the definitive confirmation of infection. La jonction costochondrale constitue un site potentiel d’infection chez le poulain septicémique et le développement de l’infection pourrait être favorisée par un traumatisme costal. Les radiographies standards et l’échographie sont des aides diagnostiques et l’aspiration ...
Golynski AA, Fernandes KR, Baldani CD, Golynski AL, Madeiro AS, Machado RZ, Botteon Pde T, Massard CL.This research was performed to study the prevalence of antibodies against Babesia equi in horses of the northern region of Rio Grande do Sul state, using ELISA and indirect immunofluorescence antibody test (IFA). The total sera sample was 380, this number was considered as statistically representative of the population, as determined by mathematical model. The prevalence of B. equi was 31.6% and 35.8% by ELISA and IFA, respectively. The concordance between the assays was 0.87 (indices kappa), which is considered an optimal result. The results did not show any significant statistical difference...
Pringle J, Roberts C, Art T, Lekeux P.This study examined the ability of near infrared spectroscopy (NIRS) to noninvasively determine changes to muscle oxygenation in the resting horse. Five horses had (NIRS) performed over extremity muscle while under general anaesthesia, first with 8 min limb ischaemia, then systemic hypoxaemia for 5 min. A second group of 6 awake horses had NIRS performed over extremity muscle while being administered hypoxic gas (F(I)O2 0.10) for 5 min, and after return to steady state, limb ischaemia was induced for an additional 5 min. In the anaesthetised horses' ischaemia induced marked and significant mus...
Pagger H, Schmidburg I, Peham C, Licka T.This aim of this study was to test the hypothesis that the stiffness of the equine cervical spine depends on the direction of force applied and on spinal position. Muscles and nuchal ligament were removed from the cervical spines of 17 horses that were without a history of cervical or neurological disease. The cervical spines were then flexed/extended dorsoventrally (with the spine straight and with the occiput rotated 30° against T1) and laterolaterally. Mean dorsoventral stiffness was 297 N/m (± 135) in flexion, 1347 N/m (± 2083) in extension, 421 N/m (± 164) in lateral flexion, 279 N/m ...
Hawkins JF, Schumacher JS, McClure SR, Light GS.Small intestinal incarceration through the lateral ligament of the urinary bladder was diagnosed in a 14-year-old, 569-kg, castrated Quarter Horse. The incarceration was corrected by ventral midline celiotomy. Approximately 70 cm of the middle portion of the jejunum was resected and end-to-end, single-layer anastomosis was performed. After surgery, the horse developed signs of adynamic ileus and lameness in the right forelimb. The horse developed laminitis in all 4 feet within 24 hours of surgery. The horse was euthanatized because of poor prognosis for survival. At necropsy, a 4.5-cm rent was...
Venugopal CS, Moore RM, Holmes EP, Koch CE, Seahorn TL, Beadle RE.To compare responses of bronchial rings obtained from healthy horses and horses affected with summer pasture-associated obstructive pulmonary disease (SPAOPD) to selected mediators of airway hyperreactivity in vitro. Methods: Bronchial rings from 6 healthy horses and 6 horses affected with SPAOPD. Methods: Bronchial rings obtained from each group of horses were mounted in organ baths and attached to force transducers interfaced with a polygraph. After applying 2g of tension, each ring was allowed to equilibrate for 45 minutes in Tyrode's solution at 37 C. Cumulative concentration-response rela...
Fanelli D, Tesi M, Rota A, Beltramo M, Conte G, Giorgi M, Barsotti G, Camillo F, Panzani D.Human Chorionic Gonadotropin (hCG) and Gonadotropin Releasing Hormone agonists (GnRHa) are routinely used to induce ovulation in mares. However, GnRHa efficacy in transitional mares has been suggested to be low. Objective: The aims of this study were as follows: (a) to compare the efficacy of hCG and GnRHa in inducing the first ovulation of the breeding season and (b) to evaluate the correlation between ovulatory response, uterine oedema and teasing score at the time of treatment during the early or late transitional phase. Methods: Randomised controlled superiority trial. Methods: Mares in wi...
Gerber R, Naudé TW, de Kock SS.Two out of a group of 23 mares exposed to tef hay contaminated with Datura ferox (and possibly D. stramonium) developed colic. The 1st animal was unresponsive to conservative treatment, underwent surgery for severe intestinal atony and had to be euthanased. The 2nd was less seriously affected, responded well to analgesics and made an uneventful recovery. This horse exhibited marked mydriasis on the first 2 days of being poisoned and showed protracted, milder mydriasis for a further 7 days. Scopolamine was chemically confirmed in urine from this horse for 3 days following the colic attack, whil...
Gabor V, Gerken M.Numerical competence is one of the aspects of animal cognition with a long history of research interest, but few results are available for the horse. In the present study, we investigated the ability of three Shetland ponies to discriminate between different quantities of geometric symbols presented on a computer screen in a matching-to-sample arrangement. In Experiment 1, the ponies had to relate two similar quantities to another, paired in contrasts (1 vs. 2, 3 vs. 4 and 4 vs. 5) of the same stimulus (dot). Specific pairs of quantities (all differing by one) of up to five different geometric...
Maclean AA, Jeffcott LB, Lavelle RB, Friend SC.The use of iohexol as a contrast agent for myelography is reported in two groups of horses. Group 1 (n = 6) were used only for myelography and to assess the clinical and pathological effects of intrathecal administration of iohexol. A volume of 20 ml at a concentration of 300 or 350 mg iodine/ml gave satisfactory myelographic detail with no serious clinical or neurological side effects. Only a minimal inflammatory response could be demonstrated in cerebrospinal fluid at four and 14 days after injection. At post mortem examination 14 days after myelography there was no evidence of meningitis no...
MacDonald MH, Honnas CM, Meagher DM.Medical records of 28 horses with osteomyelitis of the calcaneus were reviewed to evaluate signalment, history, diagnostic and treatment methods, outcome, and long-term follow-up information. Trauma was the most commonly reported cause (24). Physical examination revealed lameness in 27 horses, and 22 (79%) had a wound or draining tract over the plantar aspect of the calcaneus. Radiography of all horses was done prior to the initiation of treatment, and follow-up radiography was done on 20 horses. The most common radiographic findings were soft tissue swelling (25), bony lysis of the calcaneus ...