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.
Silva LA, Klein C, Ealy AD, Sharp DC.This work examined how the conceptus modulates endometrial tissue remodeling and vascular development prior to implantation in mares. A macroscopic uterine examination was completed at day 21 of pregnancy. In situ morphology revealed that the endometrium involved in encroachment is restricted to the dorsal endometrium immediately overlying the yolk sac. The amount of stromal area occupied by blood vessels and the number of endometrial glands were increased during early pregnancy. Endometrial histomorphometry as well as the endometrial mRNA abundance and immunolocalization of VEGF, VEGFR1, VEGF...
Kumar S, Malik P, Verma SK, Pal V, Gautam V, Mukhopadhyay C, Rai GP.Glanders, caused by the Gram-negative, nonmotile bacterium Burkholderia mallei, is a contagious and highly fatal disease of equines. During the last decade, the number of glanders outbreaks has increased steadily. The disease also has high zoonotic significance and B. mallei is listed biological warfare agent. The complement fixation test (CFT) is a routinely used and internationally recognized test to screen equine sera for the glanders. However, discrepant results have been observed using the CFT. The low sensitivity and specificity of the CFT and enzyme-linked immunosorbent assay (ELISA) ha...
Wu W, Blythe DC, Loyd H, Mealey RH, Tallmadge RL, Dorman KS, Carpenter S.Two variants of equine infectious anemia virus (EIAV) that differed in sensitivity to broadly neutralizing antibody were tested in direct competition assays. No differences were observed in the growth curves and relative fitness scores of EIAVs of principal neutralizing domain variants of groups 1 (EIAV(PND-1)) and 5 (EIAV(PND-5)), respectively; however, the neutralization-resistant EIAV(PND-5) variant was less infectious in single-round replication assays. Infectious center assays indicated similar rates of cell-to-cell spread, which was approximately 1,000-fold more efficient than cell-free ...
Chapman C, Musselwhite CBA.Horse riders represent a significant group of vulnerable road user and are involved in a number of accidents and near misses on the road. Despite this horse riders have received little attention both in terms of academic research and transport policy. Based on literature on vulnerable road user safety, including attitudes to road user safety and behaviour of drivers and their relationship with cyclists and motorcyclists, this paper examines the attitudes and reported behaviour of drivers and horse riders. A total of 46 participants took part in six focus groups divided into four groups of driv...
Pozor MA, Muehlhaus J, King A, Macpherson ML, Troedsson MH, Bailey CS.The objective was to investigate the effects of pentoxifylline (PTX) on testicular perfusion and sperm production in stallions. In a preliminary study, six mature Miniature horse stallions were given 0, 8.5, or 17.0 mg/kg of PTX orally, twice daily, for 3 d. Total Arterial Blood Flow Rate (TABFR) was higher (P < 0.05) in all treated versus control stallions during and after treatment. Two months later (during the fall and winter), the same stallions received either 0 or 17 mg/kg of PTX orally, twice daily for 60 d. Resistance and pulsatility indices (RI and PI, respectively) decreased in PT...
de Almeida GL, Santurio JM, Filho JO, Zanette RA, Camillo G, Flores AG, da Silva JH, de la Rue ML.Biological control is an alternative method to reduce the population of parasites through natural predators. A promising option of biological control in the reduction of infective larvae on pasture is the use of nematophagous fungi. In this study, the efficacy of the nematophagous fungus Duddingtonia flagrans in controlling gastrointestinal nematode parasites in field-raised horses was tested. Ten foals with an average age of 12 months were divided in two groups: five males constituted the treated group and five females constituted the control group. Each group was introduced in a field of mix...
Ben-Shlomo G, Plummer C, Barrie K, Brooks D. The goal of this work is to study the dark adaptation curve of the normal horse electroretinogram (ERG). Methods: The electroretinographic responses were recorded from six healthy female ponies using a contact lens electrode and a mini-Ganzfeld electroretinographic unit. The horses were sedated intravenously with detomidine, an auriculopalpebral nerve block was then performed, and the pupil was fully dilated. The ERG was recorded in response to a low intensity light stimulus (30 mcd.s/m(2) ) that was given at times (T) T = 5, 10, 15, 20, 25, 30, 40, 50, and 60 min of dark adapt...
Harvey AM, Williams SB, Singer ER.This study aimed to assess the effect of lateral heel studs on foot-ground interaction in the horse by quantifying foot slip during stance whilst cantering on a grass surface. It was hypothesised that using studs would decrease foot slip distance on the ground conditions tested. Nine horses were ridden with and without a stud placed laterally in the shoe of each of the 4 feet. High speed video-analysis was used to track hoof markers and to provide data quantifying foot slip distance, slip duration and stance duration. Using studs resulted in a significant decrease in foot slip distance in all ...
McFarlane D, Paradis MR, Zimmel D, Sykes B, Brorsen BW, Sanchez A, Vainio K.Plasma α-melanocyte-stimulating hormone (α-MSH) and adrenocorticotropin (ACTH) concentrations in horses vary with season, confounding diagnostic testing for pituitary pars intermedia dysfunction (PPID). Objective: The goals of this study were to determine whether seasonal variation in plasma α-MSH and ACTH concentrations in horses is influenced by geographic location, breed, or PPID. Methods: Healthy light breed horses residing in Florida, Massachusetts, and Finland (n = 12 per group); healthy Morgan horses (n = 13); healthy ponies (n = 9) and horses with PPID (n = 8). Methods: Monthly plas...
Alcott CJ, Sponseller BA, Wong DM, Davis JL, Soliman AM, Wang C, Hsu W.Ketamine has immunomodulating effects both in vitro and in vivo during experimental endotoxemia in humans, rodents, and dogs. Objective: Subanesthetic doses of ketamine will attenuate the clinical and immunologic responses to experimental endotoxemia in horses. Methods: Nineteen healthy mares of various breeds. Methods: Experimental study. Horses were randomized into 2 groups: ketamine-treated horses (KET; n = 9) and saline-treated horses (SAL; n = 10). Both groups received 30 ng/kg of lipopolysaccharide (LPS, Escherichia coli, O55:B5) 1 hour after the start of a continuous rate infusion (CRI)...
Pauvolid-Corrêa A, Morales MA, Levis S, Figueiredo LT, Couto-Lima D, Campos Z, Nogueira MF, da Silva EE, Nogueira RM, Schatzmayr HG.Despite evidence of West Nile virus (WNV) activity in Colombia, Venezuela and Argentina, this virus has not been reported in most South American countries. In February 2009, we commenced an investigation for WNV in mosquitoes, horses and caimans from the Pantanal, Central-West Brazil. The sera of 168 horses and 30 caimans were initially tested using a flaviviruses-specific epitope-blocking enzyme-linked immunosorbent assay (blocking ELISA) for the detection of flavivirus-reactive antibodies. The seropositive samples were further tested using a plaque-reduction neutralisation test (PRNT90) for ...
Jorge RS, Ferreira F, Ferreira Neto JS, Vasconcellos Sde A, Lima Ede S, Morais ZM, Souza GO.Leptospirosis is a zoonotic disease affecting most mammals and is distributed throughout the world. Several species of domestic and wild animals may act as reservoirs for this disease. The purpose of this study was to assess the exposure of free-ranging wild carnivores, horses and domestic dogs on a private reserve located in the northern Pantanal (Brazil) and the surrounding areas to Leptospira spp from 2002-2006, 75 free-ranging wild carnivores were captured in the Pantanal and serum samples were collected. In addition, samples from 103 domestic dogs and 23 horses in the region were collecte...
Pitzer JB, Kaufman PE, Hogsette JA, Geden CJ, Tenbroeck SH.Beginning in November 2007 and continuing until December 2009, weekly stable fly, Stomoxys calcitrans (L.), surveillance was conducted at four equine facilities near Ocala, FL, by using alsynite sticky traps for adults and by searching immature developmental sites for pupae. Adult stable fly trap captures were highly variable throughout the year, ranging from 0 to 1,400 flies per trap per farm. The greatest adult stable fly activity was observed during the spring months of March and April, with weekly three-trap means of 121 and 136 flies per farm, respectively. The importance of cultural cont...
Begg AP, Reece RL, Hum S, Townsend W, Gordon A, Carrick J.Analysis of pathology results from the 2007 equine influenza (EI) outbreak in Australia indicate that young foals in naïve horse populations are prone to developing broncho-interstitial pneumonia, and that this can be a rare manifestation of EI virus infection in mature horses. All horses may develop secondary bacterial bronchopneumonia, with mature horses more likely to die. EI outbreaks among heavily pregnant mares can result in increased neonatal losses because of premature placental separation and dystocia causing fetal hypoxia.
Smyth GB, Dagley K, Tainsh J.We estimate and describe the financial costs of the equine influenza (EI) outbreak in Australia, including the costs of emergency response measures and lost income/assets to businesses, associations and private horse owners. Costs to associations, governments and industry are discussed. We identify a lack of reliable data about the financial costs of the EI outbreak to the non-racing sectors of the horse industry.
Arthur RJ, Suann CJ.Three biosecurity and relief-and-recovery initiatives adopted by the NSW horse racing industries reduced the economic and social disruption caused by the disease and subsequent movement controls during the 2007 Australian equine influenza (EI) incursion. The first was the creation of biosecure horse training and racing precincts around the Sydney area to permit racing to continue with healthy horses. Infection was excluded for 3-5 weeks and race meetings were conducted safely during this period. The second was a vaccination program of racehorses at these and other precincts to maintain an ongo...
Read AJ, Finlaison DS, Gu X, Davis RJ, Arzey KE, Kirkland PD.During the equine influenza (EI) outbreak, two assays were used in parallel to diagnose the disease, to demonstrate freedom from infection in disease control zones and ultimately to demonstrate that EI virus had been eliminated from the Australian horse population. A longitudinal study of a population of naturally infected horses was established to determine the performance characteristics of these assays.
Watson J, Selleck P, Axell A, Bruce K, Taylor T, Heine H, Daniels P, Jeggo M.In August 2007, several horses showed pyrexia and respiratory signs while in post-arrival quarantine in Australia. Subsequent investigations diagnosed equine influenza by serology and PCR in two quarantine stations. A common origin in a shipment of horses from Japan was indicated.
Dups JN, Morton JM, Anthony ND, Dwyer JF.This report describes the clinical signs of equine influenza (EI) during an epidemic in a closed, predominantly immunologically naïve population of horses. It included 254 study horses, few of which exhibited all three signs of pyrexia, nasal discharge and cough simultaneously. We conclude that although the majority of affected horses exhibit temperature patterns resembling those most often described in the published literature, clinicians should be aware that other profiles are quite common.
Wong D.The clinical signs of horses diagnosed with equine influenza (EI) at Centennial Parklands Equestrian Centre (CPEC) and the events surrounding their diagnosis are described. This was the site of the first case of EI diagnosed outside of the Eastern Creek Animal Quarantine Station. The clinical data demonstrate the rapid spread of the disease after a sufficient viral load had developed from the initial cases within CPEC.
Kirkland PD.During the 2007 equine influenza (EI) outbreak in Australia, diagnostic laboratories and the use of appropriate tests played a pivotal role in the response to the crisis. This role began with the detection of EI virus in New South Wales (NSW) on the evening of 24 August 2007 and culminated in providing the final 'proof of freedom' from EI in March 2008. The tests that were used during the EI response were able to provide results quickly, and with high sensitivity and specificity. This section of the supplement describes the roles and functions of the Australian laboratories; tests used and the...
Franci P, Bertamini A, Bertamini O, Pilla T, Busetto R.A new volatile anaesthetic agent delivery system was tested in 15 horses undergoing scheduled surgical procedures. The delivery system consisted of a laptop computer (with dedicated software), a computer-controlled syringe driver (loaded with liquid isoflurane) connected to the inspiratory arm of a large-animal circle breathing system and a respiratory gas monitor, providing isoflurane end-tidal concentrations (ET(measured)) every 20 s to the computer. Following induction and connection to the breathing system, mechanical ventilation was started. The bodyweight (BW), fresh gas flow, breathing ...
Hoare R.The equine influenza (EI) outbreak occurred at the worst time of the year as far as the horse industry was concerned. All horse sports and horse breeds had events planned in the spring, including those relating to qualification for the 2008 Beijing Olympic Games. These were all disrupted and many were cancelled. The social and industry impacts were extensive, and included difficulties related to communication, animal welfare, vaccination, movement restrictions, economics, as well as the psychological stresses experienced by those involved, especially those for whom their primary source of inco...
Myers J.At the outbreak of equine influenza (EI) we chose to close our horse-based business, as we did not want to risk our horses contracting the disease and the demand for our services ceased. We report our experiences of the outbreak.
Garner MG, Cowled B, East IJ, Moloney BJ, Kung N.To use modelling and epidemiological analyses to assess the effectiveness of control strategies employed during the equine influenza outbreak and determine if early vaccination might have had a beneficial effect. Methods: Transmission of infection was modelled using stochastic, spatial simulation, based on data from 16 regions in New South Wales and Queensland over the first month of the outbreak. Results: The model accurately represented the spread of infection in both space and time and showed that vaccination strategies would have reduced new infections by ∼60% and reduced the size of the...
Frazer JL, Perkins NR, Pitt D.During the 2007 equine influenza (EI) outbreak, infected horses were quarantined at Morgan Park Recreational Grounds (MPRG) near Warwick, Queensland. Some individuals caring for horses were reported to have made return journeys between MPRG and home properties containing other horses during the time there was active infection at MPRG. Objective: A retrospective cohort study to assess the biosecurity and hygiene measures undertaken and their outcomes. Methods: All individuals recorded as being responsible for caring for one or more horses at MPRG, and who were also recorded on entry and exit lo...
Kannegieter NJ, Frogley A, Crispe E, Kirkland PD.As part of the control measures of the equine influenza (EI) outbreak, in addition to the strategic use of vaccination to provide buffer zones around infected populations, approval was obtained to vaccinate Thoroughbred racing horses. We review the clinical expression of the disease and virus excretion in a population of racehorses that were exposed to EI approximately 7 days after administration of a single dose of the canarypox-vectored recombinant compared with a similar unvaccinated population of horses at a nearby racetrack. Although this study was undertaken opportunistically and under t...
Happold J, Rubira R.This study included 10 large Thoroughbred horse studs in the upper Hunter Valley of New South Wales and in southeast Queensland, Australia. The aims were to describe the EI epidemic in studs in the Special Restricted Area (Purple Zone) of NSW, to estimate seroprevalence among different groups of horses on these studs and to look for evidence of exposure to EI virus in horses on 'vaccinated' studs in southeast Queensland that were thought to have remained free of infection. As serology results from Queensland suggest that vaccination may have reduced the sensitivity of clinical surveillance to ...
Sergeant ES, Cowled BD, Bingham P.This observational study was undertaken in order to evaluate the diagnostic specificity of the blocking enzyme-linked immunosorbent assay (bELISA) for serum antibodies to influenza A virus nucleoprotein during the equine influenza (EI) outbreak response in New South Wales, Australia, in 2007. Using data collected during the outbreak response, bELISA testing data were collated for assumed uninfected horses from areas where EI infection was never recorded. Diagnostic specificity of the bELISA used during the EI response was high, but varied significantly between some regions, although the reason...
Wilson G, Cooper K, Williams J, Eastwood S, Peake C.The 2007 equine influenza (EI) outbreak in New South Wales (NSW) consisted of a central infected area that extended south from the lower New England Tableland, across the Hunter Valley, Central Coast and the Sydney basin, and a series of isolated clusters outside this area across rural NSW. The central area was assigned the status of a Purple Zone (Special Restricted Area, SRA) approximately 1 month after the outbreak commenced. Within this SRA, the eradication program's focus was to increase the proportion of horses immune to EI via vaccination, thus reducing the susceptible proportion to a l...
Wilsher S, Allen WR.There is a paucity of information on factors that influence placental development in the horse. Objective: Changes in nutrition, particularly around the time of proliferative placental growth, can affect development of the placenta and fetal growth. Objective: To investigate the effects of 2 planes of nutrition and an unforeseen infection-mediated nutritional insult on placental and fetal development in the mare. Methods: Twenty maiden Thoroughbred fillies, age 3 or 4 years, mated to one Thoroughbred stallion, were maintained on either High or Moderate food intake throughout pregnancy. In mid-...
Eksell P, Uhlhorn H, Carlsten J.Radiographs from 196 tarsi in 98 Icelandic horses were evaluated to compare the accuracy of four different projections in detecting radiographic signs of degenerative joint disease in the distal tarsus. The extent and localization of tarsal degenerative joint disease found in one projection when reading all four projections of the same tarsus together was compared with the combined findings from all four projections. The results of reading individual radiographic projections without knowledge of the other three projections was also evaluated. Degenerative joint disease was detected most freque...
Much ML, Leatherwood JL, Zoller JL, Bradbery AN, Martinez RE, Keegan AD, Lamprecht ED, Wickersham TA.Stock-type mares (498 ± 9 kg BW; 12 ± 7 yr) were used in a completely randomized design for 56 d to test the hypothesis that concentrate fortification improves apparent digestion and enhances lean mass over the topline. Horses were stratified by age, BW, and BCS and randomly assigned to either a custom pelleted concentrate (CON; = 13), or an iso-caloric, iso-nitrogenous pellet that included amino acid fortification, complexed trace minerals, and fermentation metabolites (FORT; = 10). Concentrate was offered at a total 0.75% BW/d (as-fed) twice daily, and diets were designed to meet or exce...
Hassel DM, Langer DL, Snyder JR, Drake CM, Goodell ML, Wyle A.To identify breed, age, sex, physical findings, history, and outcome of treatment in horses and other equids with enterolithiasis. Methods: Retrospective study. Methods: 900 equids with enterolithiasis. Methods: Medical records from equids with enterolithiasis admitted between 1973 and 1996 were reviewed. Data on signalment, history, physical examination and clinicopathologic findings, surgical findings, and outcome were compiled from records and from telephone interviews with owners. Sex and breed predilections were determined by comparison of the study population with the general hospital po...
Hifumi T, Tanaka T, Hernandez EP, Akioka K, Yamada K, Imamura Y, Hatai H, Miyoshi N.Histopathological and genetic examinations were conducted on grayish-white solid hepatic nodules in 150 horses imported from Canada, in order to investigate larval Echinococcus multilocularis infection. Ten of the 150 horses (6.7%) were diagnosed with alveolar hydatid disease. The sequences of the mitochondrial cytochrome b genes obtained from all 10 polymerase chain reaction positive samples had 99 to 100% identity with the European haplotype E1 of E. multilocularis. Therefore, we concluded that the infections likely originated in Canada. Relation entre les nodules hépatiques solides blanc-g...
Squires EL.Marked changes in equine breeding technologies have occurred over the past 25 years. Although there have been numerous reviews on assisted reproduction techniques for horses, few publications include the acceptance and impact of these techniques on the horse industry. In this review, several techniques are discussed, with an emphasis on how they developed in the horse industry and altered equine reproductive medicine. Embryo transfer has become a widely used technology, allowing multiple foals to be produced per year. Embryos can be collected, cooled or frozen, and shipped to a distant facilit...
Sullivan EK, Klein LV, Richardson DW, Ross MW, Orsini JA, Nunamaker DM.To describe the pool-raft recovery system protocol and to evaluate the clinical outcome in horses that underwent recovery from general anesthesia using this system. Methods: Retrospective study. Methods: 393 horses that underwent recovery from general anesthesia in the pool-raft system. Methods: Anesthetic records were examined from horses recovered from anesthesia in the pool-raft system between January 1984 and December 2000. Complete medical records of horses were examined when available. Information regarding the anesthetic and recovery period was recorded. Horses first recovered from gene...
Cosandey J, Hamza E, Gerber V, Ramseyer A, Leeb T, Jagannathan V, Blaszczyk K, Unger L.MicroRNAs have been proposed as biomarkers for equine sarcoids, the most prevalent equine skin tumors globally. This study served to validate the diagnostic and prognostic potential of whole blood microRNAs identified in a previous study for long-term equine sarcoid diagnosis and outcome prediction. Based on findings of a clinical examination at the age of 3 years and a follow-up following a further 5-12 years, 32 Franches-Montagnes and 45 Swiss Warmblood horses were assigned to four groups: horses with regression (n = 19), progression (n = 9), new occurrences of sarcoid lesions (n = 19) and t...
Pagliara E, Marenchino M, Antenucci L, Costantini M, Zoppi G, Giacobini MDL, Bullone M, Riccio B, Bertuglia A.Fetlock joint angle (FJA) pattern is a sensitive indicator of lameness. The first aim of this study is to describe a network of inertial measurement units system (IMUs) for quantifying FJA simultaneously in all limbs. The second aim is to evaluate the accuracy of IMUs for quantifying the sagittal plane FJA overground in comparison to bi-dimensional (2-D) optical motion capture (OMC). 14 horses (7 free from lameness and 7 lame) were enrolled and analyzed with both systems at walk and trot on a firm surface. All enrolled horses were instrumented with 8 IMUs (a pair for each limb) positioned at t...
Segura D, Monreal L, Espada Y, Pastor J, Mayós I, Homedes J.The objective of this study was to assess whether a new human platelet function analyser (the PFA-100) could be used to evaluate platelet function in horses and detect acetylsalicylic acid (ASA)-induced platelet dysfunctions. Citrated blood samples from 40 healthy horses were processed to obtain reference values for closure time (CT) using cartridges with collagen-ADP (CT-ADP) and collagen-epinephrine (CT-EPI) as platelet agonists. In addition, CT-ADP and CT-EPI were also measured before and 24 h after oral ASA administration in another 12 healthy horses. The sensitivity and specificity of the...
Colglazier ML, Enzie FD, Kates KC.The comparative efficacy of four benzimidazoles against gastrointestinal parasites of ponies was evaluated by the critical test method. Mebendazole (8.8 mg/kg), cambendazole (20 mg/kg), fenbendazole (5 mg/kg), and albendazole (2.5 and 5 mg/kg) given in single oral doses were highly effective against adult large strongylids (Strongylus vulgaris, S. endentatus, S. equinus) and adult small strongylids (genera identified in order of frequency: Cylicostephanus, Cylicocyclus, Cyathostomum, Triodontophorus, Poteriostomum, Oesophagodontus, Cylicodontophorus, Gyalocephalus, and Craterostomum). Limited ...
King DS, Tulleners E, Martin BB, Parente EJ, Boston R.To describe the clinical findings in 52 racehorses with axial deviation of the aryepiglottic folds (ADAF) and to report outcome in 33 of these horses after either rest or transendoscopic laser excision of aryepiglottic fold tissue. Methods: Retrospective study. Methods: Racehorses admitted for high-speed treadmill (HST) evaluation of poor performance. Methods: Medical records and videotapes of resting and exercising videoendoscopic examinations were reviewed. Racing performance records and owner or trainer interviews, at least 1 year after HST examination, were used to compare results after ei...
Franklin SH, Naylor JR, Lane JG.Dorsal displacement of the soft palate (DDSP) is one of the most common obstructive conditions of the upper respiratory tract in the racehorse. The present study was conducted to determine the effects of intermittent dorsal displacement of the soft palate (DDSP) on ventilation and respiratory airflow during high intensity exercise. Videoendoscopic recordings were made of the nasopharynx and larynx simultaneously with measurements of airflow and respiratory gas exchange, during high-speed treadmill exercise in 9 horses with confirmed intermittent DDSP admitted for clinical investigation of poor...
Bishop RC, Kemper AM, Burges JW, Jandrey KE, Wilkins PA.To evaluate a point-of-care viscoelastic coagulation monitor (VCM Vet) for use in horses by assessing variability between devices and establish reference intervals (RIs) for healthy adult horses. Methods: Prospective observational study. Methods: Two university teaching hospitals. Methods: Healthy adult horses (n = 68). Methods: None. Results: Blood collected by direct jugular venipuncture was applied directly from the syringe into 2 VCM Vet cassettes to establish coefficients of variation (CVs) and RIs for reported parameters of clotting time (CT), clot formation time (CFT), alpha angle, am...
Davis JL, Papich MG, Morton AJ, Gayle J, Blikslager AT, Campbell NB.The purpose of this study was to determine the pharmacokinetics of etodolac following oral and intravenous administration to six horses. Additionally, in vitro cyclooxygenase (COX) selectivity assays were performed using equine whole blood. Using a randomized two-way crossover design, horses were administered etodolac (20 mg/kg) orally or intravenously, with a minimum 3-week washout period. Plasma samples were collected after administration for analysis using high pressure liquid chromatography with ultraviolet detection. Following intravenous administration, etodolac had a mean plasma half-li...
Govan JR, Sarasola P, Taylor DJ, Tatnell PJ, Russell NJ, Gacesa P.The isolation and characterization of a mucoid, alginate-producing strain of Pseudomonas aeruginosa from a nonhuman host, namely, in chondroids from an equine guttural pouch, is reported for the first time. Pure cultures of P. aeruginosa 12534 were isolated from a 17-month-old pony mare with a history of chronic bilateral mucopurulent nasal discharge from the right guttural pouch. Transmission electron microscopy of chondroids showed mucoid P. aeruginosa growing as microcolonies within a matrix of extracellular material. On the basis of expression of the mucoid phenotype under different growth...
Sasaki M, Kim E, Igarashi M, Ito K, Hasebe R, Fukushi H, Sawa H, Kimura T.Equine herpesvirus-1 (EHV-1), an α-herpesvirus of the family Herpesviridae, causes respiratory disease, abortion, and encephalomyelitis in horses. EHV-1 utilizes equine MHC class I molecules as entry receptors. However, hamster MHC class I molecules on EHV-1-susceptible CHO-K1 cells play no role in EHV-1 entry. To identify the MHC class I molecule region that is responsible for EHV-1 entry, domain exchange and site-directed mutagenesis experiments were performed, in which parts of the extracellular region of hamster MHC class I (clone C5) were replaced with corresponding sequences from equine...
Kohn CW, Fenner WR.The neurologic form of EHV-1 infection appears to be the result of central nervous system infarction caused by vasculitis, which is initiated in endothelial cells of small blood vessels. The etiologic agent is equine herpesvirus-1, subtype 1. There is some evidence to suggest that the neurologic form of the disease actually results from reactivation of a previous infection. Whether the vasculitis that causes the central nervous system injury is the direct result of the infection or an immune response to the infection has not been determined. The clinical signs are rapid in onset, nonprogressiv...
Gustafson SB, McIlwraith CW, Jones RL, Dixon-White HE.Polysulfated glycosaminoglycan (PSGAG) recently have been reported to potentiate the infectivity of Staphylococcus aureus in horses with experimentally induced septic arthritis. Four groups of 8 horses each had 1 midcarpal joint injected with approximately 33 viable colony-forming units (CFU) of S aureus plus either 1 ml of saline solution (group 1), 250 mg of PSGAG (group 2), 250 mg of PSGAG passed through a 0.6-microns filter (group 3), or 250 mg of PSGAG plus 125 mg of amikacin (group 4). Horses that developed clinical signs consistent with sepsis were euthanatized, and samples were collect...
Bell IG, Drury-Klein C.To analyse horse event and horse movement registration data collected between September 2007 and December 2008 during the outbreak of equine influenza in New South Wales, Australia. Results: A total of 9356 events were registered, involving 504,382 horses and 242,952 riders. Registered horse movements totalled 224,084, involving 349,327 horses (excluding mobs) travelling 34.4 million km with an average of 154 km per journey. The number of recorded events and movements were low while movement controls were most stringent, then increased from December 2007 as restrictions were eased, to peak in ...
Mansour C, Chaaya R, Sredensek J, Mocci R, Santangelo B, Allaouchiche B, Bonnet-Garin JM, Boselli E, Junot SA.To compare the sublingual microcirculation between healthy horses anesthetized for elective procedures and horses with colic anesthetized for abdominal surgery and to determine the effect of mean arterial blood pressure (MAP) on the microcirculation. Methods: 9 horses in the elective group and 8 horses in the colic group. Methods: Sublingual microcirculation was assessed with sidestream dark field video microscopy. Videos were captured at 3 time points during anesthesia. Recorded microvasculature parameters were De Backer score (DBS), total density of perfused vessels (PVD) and small vessels (...
Melrose PA, Walker RF, Douglas RH.Catecholamine concentrations (pg/ml) in the cerebrospinal fluid (CSF) of prepubertal (n = 9) and adult (n = 18) horses were determined by radioenzymatic assay. Norepinephrine was low or non detectable in all CSF samples. In contrast, measurable CSF dopamine concentrations were effected by age, reproductive status and exogenous steroid treatments. The concentration of dopamine in the CSF of prepubertal females (733 +/- 92) was greater (p less than 0.05) than the concentration in the CSF of prepubertal males (117 +/- 67). Prepubertal male horses which were treated with testosterone for 5 days (5...
Dorey NR, Conover AM, Udell MA.The ability of many domesticated animals to follow human pointing gestures to locate hidden food has led to scientific debate on the relative importance of domestication and individual experience on the origins and development of this capacity. To further explore this question, we examined the influence of different prior training histories/methods on the ability of horses (Equus ferus caballus) to follow a momentary distal point. Ten horses previously trained using one of two methods (Parelli™ natural horsemanship or traditional horse training) were tested using a standard object choice tas...
Kitaura T, Sato F, Hada T, Ishimaru M, Kodama R, Nambo Y, Watanabe G, Taya K.The secretion of prolactin and growth hormone in response to exercise and emotional stresses was investigated in Thoroughbreds. Two experiments were performed: one with loading of only exercise stress and one with simultaneous loading of exercise and emotional stresses. Exercise stress was loaded in 4 steps using a treadmill for horses: pre-exercise period (5 min), walking period (6.5 min), galloping period (3 min), and cooling down period (10 min). Emotional stress was loaded by showing a loud video of an audience at a racetrack during the walking period. The results clearly demonstrated that...
Walsh DM, Royal HD.Glomerular filtration rate (GFR) was measured in 12 clinically normal horses, using the standard inulin clearance method, and values were compared with values for 2 methods, using a single rapid IV injection of 99mTc-labeled diethylenetriaminepentaacetic acid (99mTc-DTPA). The first 99mTc-DTPA method used a 2-compartment model to calculate GFR blood clearance of the tracer. The second method used sequential digital gamma camera images of the kidneys to determine fractional accumulation of the total dose of the tracer in the kidneys (percentage of injected dose, gamma camera) from 0 to 10 minut...
Goodwin WA, Pasloske K, Keates HL, Ranasinghe MG, Woldeyohannes S, Perkins N.To determine the suitability of alfaxalone total intravenous (IV) anaesthesia in horses and concurrently evaluate infusion rates, cardiovascular effects, pharmacokinetics and the quality of the anaesthetic recovery period. Methods: Prospective, experimental study. Methods: Eight Standardbred horses. Methods: Horses were premedicated with IV acepromazine (0.03 mg kg) and xylazine (1 mg kg) and anaesthesia was induced with guaifenesin (35 mg kg) and alfaxalone (1 mg kg). Anaesthesia was maintained for 180 minutes using an IV infusion of alfaxalone at a rate determined by a horse's response to a ...
Coryn M, De Morr A, Bouters R, Vandeplassche M.The authors analysed clinical, histological and hormonal data obtained from 205 cryptorchid horses. The majority of the unilaterally and bilaterally retained testes were located in the inguinal canal; however, the ratio of inguinal vs abdominal retention appeared to decrease with advancing age. In unilateral cryptorchidism, a pronounced preference was noted for left abdominal retention, whereas for inguinal cryptorchids, the retained testes occurred equally on both sides. Right inguinal retention was found to decrease with advancing age. Histology of cryptorchid testes revealed apparently norm...
Montgomery JB, Husulak ML, Kosolofski H, Dos Santos S, Burgess H, Meachem MD.The objective of this study was to determine if TNF-α protein concentration differs in bronchoalveolar lavage fluid (BALF) obtained from healthy horses, horses with naturally occurring exacerbations of severe equine asthma and horses in remission from severe equine asthma. Tumor necrosis factor-alpha (TNF- α) protein concentrations were determined in BALF by commercial equine ELISA. Horses with naturally occurring exacerbation of severe equine asthma were found to have significantly lower BALF TNF-α protein concentrations than healthy horses (p = 0.0026). There was no significant differ...
