"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.
Watts AE, Nixon AJ, Reesink HL, Cheetham J, Fubini SL, Looney AL.To investigate the efficacy and safety of a low-volume, single-catheter, continuous peripheral neural blockade (CPNB) technique to locally deliver bupivacaine to alleviate signs of severe forelimb pain resulting from experimentally induced tendonitis in horses. Methods: Randomized controlled experimental trial. Methods: 14 horses and 5 forelimbs from equine cadavers. Methods: Horses underwent collagenase-induced superficial digital flexor tendonitis in the midmetacarpal region of 1 forelimb. To deliver analgesia, a closed-tip catheter was placed from lateral to medial, approximately 12 cm dist...
Dyson SJ, Tranquille CA, Collins SN, Parkin TD, Murray RC.There is little scientific evidence to support the premise that poor foot conformation predisposes to foot pain and lameness. Objective: To determine relationships between external characteristics of the hoof capsule and angles of the distal phalanx; to determine variability in shape of the distal phalanx; and to investigate association between distal phalanx angles and the injury causing lameness. Methods: Feet were documented photographically and radiographically. Linear and angle measurements were obtained for the hoof capsule and distal phalanx and compared statistically. Horses were categ...
Hopster K, Kästner SB, Rohn K, Ohnesorge B.To compare, ventilation using intermittent positive pressure ventilation (IPPV) with constant positive end-expiratory pressure (PEEP) and alveolar recruitment manoeuvres (RM) to classical IPPV without PEEP on gas exchange during anaesthesia and early recovery. Methods: Prospective randomized study. Methods: Twenty-four warm-blood horses, weight mean 548 ± SD 49 kg undergoing surgery for colic. Methods: Premedication, induction and maintenance (isoflurane in oxygen) were identical in all horses. Group C (n = 12) was ventilated using conventional IPPV, inspiratory pressure (PIP) 35-45 cmH2O; gr...
Müller K, Ellenberger C, Hoppen HO, Schoon HA.The first part of our study (Müller et al., 2009) characterized angiogenesis in the equine cycling ovary through histomorphological and immunohistochemical examinations (vascular endothelial growth factors A and B [VEGF A, VEGF B], vascular endothelial growth factor receptors 1 and 2 [VEGF-R1, VEGF-R2], vascular angiopoietins 1 and 2 [Ang1, Ang2], angiopoietin receptor [Tie2], and von Willebrand Factor). Since angiogenesis plays an important role in development and growth of numerous tumours, the second part of our study involved a similar examination of 70 equine granulosa cell tumours (GCTt...
van de Goor LH, van Haeringen WA, Lenstra JA.As a consequence of the close integration of horses into human society, equine DNA analysis has become relevant for forensic purposes. However, the information content of the equine Short Tandem Repeat (STR) loci commonly used for the identification or paternity testing has so far not been fully characterized. Population studies were performed for 17 polymorphic STR loci (AHT4, AHT5, ASB2, ASB17, ASB23, CA425, HMS1, HMS2, HMS3, HMS6, HMS7, HTG4, HTG6, HTG7, HTG10, LEX3 and VHL20) including 8641 horses representing 35 populations. The power of parental exclusion, polymorphic information content...
Cuervo-Arango J, Beg MA, Ginther OJ.The objective was to determine differences in follicle and reproductive hormone characteristics in mares with ovulatory and flunixin meglumine (FM)-induced anovulatory cycles. Estrous mares were given 1500 IU hCG when the follicle was ≥ 32 mm (0 h). In Experiment 1, control mares (n = 7) were not treated further. The remaining mares (n = 11) were given 1.7 mg/kg FM i.v. twice daily, from 0 to 36 h after hCG treatment. Blood samples and ultrasonographic examinations were performed every 12 h. All control mares ovulated normally between 36 and 48 h. In contrast, eight of 11 FM mares did not ov...
Zizzadoro C, Caruso M, Putignano C, Crescenzo G, Ormas P, Belloli C.The effects of endotoxin on β-adrenergic-mediated relaxation were investigated in the equine digital artery (EDA). Possible involvement of cyclooxygenase-2 (COX-2) in endotoxin-induced effects and basal EDA β-adrenoceptor functionality was also evaluated. Endothelium-intact (e(+)) and/or -denuded (e(-)) EDA rings were incubated overnight with lipopolysaccharide (LPS), LPS+NS398 (selective COX-2 inhibitor) or NS398 alone. Vessel rings were then mounted in organ baths and relaxant responses to isoproterenol (ISOP) recorded on U44069-induced pre-contraction. Response to ISOP was further evaluat...
Soma LR, Uboh CE, You Y, Guan F, McDonnell S.Pennsylvania (PA) State Racing Commissions regulate the endogenous androgenic steroid, testosterone (TES), in racing intact males (RIM) by quantification of TES in post-race samples. Post-race plasma samples (2209) collected between March 2008 and November 2010 were analyzed for TES, nandrolone (NAN), and other anabolic steroids (ABS). Of the 2209 plasma samples, 2098 had quantifiable TES ≥ 25 pg/mL. Plasma (mean ± SD) concentrations of TES and NAN in RIM were 329.2 ± 266.4 and 96.0 ± 67.8 pg/mL, respectively. Only 64.6% of RIM had quantifiable concentration of NAN, and there was no relat...
Dauvillier J, Felippe MJ, Lunn DP, Lavoie-Lamoureux A, Leclère M, Beauchamp G, Lavoie JP.Corticosteroids currently are the most effective pharmacological treatment available to control heaves in horses. Systemically administered corticosteroids have been shown to alter immune response in horses, humans, and other species. Aerosolized administration theoretically minimizes systemic adverse effects, but the effect of inhaled corticosteroids on immune function has not been evaluated in horses. Objective: To evaluate the effects of prolonged administration of inhaled fluticasone on the immune system of heaves-affected horses. Methods: Heaves-affected horses were treated with inhaled f...
Kyvsgaard NC, Lindbom J, Andreasen LL, Luna-Olivares LA, Nielsen MK, Monrad J.Horses, mules and donkeys are indispensable farming and working animals in many developing countries, and their health status is important to the farmers. Strongyle parasites are ubiquitous in grazing horses world-wide and are known to constitute a threat to equine health. This study determined the prevalence of strongyle infection, the efficacy of ivermectin and fenbendazole treatment, and strongyle re-infection rates of working horses during the dry months in Nicaragua. One hundred and five horses used by farmers for transport of people and goods were randomly allocated into three treatment ...
Love EJ, Taylor PM, Murrell J, Whay HR, Waterman-Pearson AE.The aim of this randomised, observer-blinded, crossover study was to compare the effects of four treatments, administered intravenously to six horses: saline and saline; 10 µg/kg detomidine and 7.5 µg/kg buprenorphine; 20 µg/kg detomidine and 7.5 µg/kg buprenorphine; and 20 µg/kg detomidine and 10 µg/kg buprenorphine. Sedation was subjectively assessed and recorded on a visual analogue scale. Peak sedation and duration of sedation were investigated using a univariate general linear model with post-hoc Tukey tests (P<0.05). Increasing the dose of detomidine from 10 to 20 µg/kg increas...
Ribeiro MF, da Silveira JA, Bastos CV.Tick-borne diseases in horses are caused by the intraerythrocytic protozoan parasites Theileria equi and Babesia caballi. Although T. equi is highly endemic in Latin America, the New World vector of this important parasite is controversial. The aim of this study was to test the ability of nymph Amblyomma cajennense ticks acquire infection by T. equi following feeding on infected horses. Three experiments were performed: tick acquisition of T. equi from an experimentally infected horse, tick acquisition of T. equi from naturally infected foals and tick acquisition of T. equi from a chronically ...
Hofmaier F, Hauck SM, Amann B, Degroote RL, Deeg CA.Autoimmune uveitis is a sight-threatening disease in which autoreactive T cells cross the blood-retinal barrier. Molecular mechanisms contributing to the loss of eye immune privilege in this autoimmune disease are not well understood. In this study, the authors investigated the changes in the matrix metalloproteinase network in spontaneous uveitis. Methods: Matrix metalloproteinase (MMP) MMP2, MMP9, and MMP14 expression and tissue inhibitor of metalloproteinase (TIMP)-2 and lipocalin 2 (LCN2) expression were analyzed using Western blot quantification. Enzyme activities were examined with zymog...
Firestone SM, Schemann KA, Toribio JA, Ward MP, Dhand NK.The 2007 epidemic of equine influenza in Australia provided an opportunity to investigate the effectiveness of on-farm biosecurity measures in preventing the spread of a novel pathogen in a largely naive population. We conducted a case-control study of 200 horse premises from highly affected regions of the state of New South Wales (NSW), to investigate risk factors for the spread of equine influenza onto horse premises, specifically, non-compliance with biosecurity measures recommended to horse owners by the relevant animal health authority, the NSW Department of Primary Industries. The study ...
Hinney B, Wirtherle NC, Kyule M, Miethe N, Zessin KH, Clausen PH.The objective of the study was to estimate the prevalence of helminths in the horse population of the state of Brandenburg, Germany. One hundred and twenty-six horse farms in the state were selected by randomised stratified sampling. In total, 1,407 horses across all farms were examined coproscopically. The experimental unit was the horse farm: a farm was considered infected when at least one horse on the farm investigated was positive for helminth eggs. Animal details such as age, breed and sex were collected for all study horses and analysed for risk of infection. Risk was defined as horses ...
Ramzan PH, Dallas RS, Palmer L.To evaluate a technique for oral extraction of fractured cheek teeth (CT) under oral endoscopic guidance. Methods: Case series. Methods: Horses (n = 30) with fractured CT. Methods: Medical records (April 2007-August 2010) of horses that had standing oral extraction of fractured CT under endoscopic guidance were reviewed. Results: Thirty horses (median age, 11.5 years; range, 5-23 years) had 31 fractured CT (21 maxillary, 10 mandibular) removed. Midline sagittal fractures of maxillary teeth (n = 13; 42%) were the most common type, followed by buccal or palatal (10; 32%), and transverse or multi...
Yuan Z, Gault EA, Campo MS, Nasir L.Equine sarcoids represent the most common skin tumours in equids worldwide, characterized by extensive invasion and infiltration of lymphatics, rare regression and high recurrence after surgical intervention. Bovine papillomavirus type-1 (BPV-1) and less commonly BPV-2 are the causative agents of the diseases. It has been demonstrated that BPV-1 viral gene expression is necessary for maintaining the transformation phenotype. However, the underlying mechanism for BPV-1 transformation remains largely unknown, and the cellular factors involved in transformation are not fully understood. Previousl...
Breuer J, Müller U, Locher L, Spallek A, Recknagel S, Uhlig A, Schusser GF.Proinflammatoric cytokines are released extracellularly during necrosis. These lead to inflammation and destruction of surrounding tissues. The aim of this study was to compare the number of viable, apoptotic and necrotic cells in the bronchoalveolar lavage fluid (BALF) of normal horses and horses with recurrent airway obstruction (RAO) and to determine if fluorescence microscopy is a reliable method for this examination. A group of six normal horses and a group of ten horses with RAO were examined. Samples were assessed using annexin-V and propidium iodide immunofluorescence assay and examine...
Andersson LS, Lyberg K, Cothran G, Ramsey DT, Juras R, Mikko S, Ekesten B, Ewart S, Lindgren G.The syndrome Multiple Congenital Ocular Anomalies (MCOA) is the collective name ascribed to heritable congenital eye defects in horses. Individuals homozygous for the disease allele (MCOA phenotype) have a wide range of eye anomalies, while heterozygous horses (Cyst phenotype) predominantly have cysts that originate from the temporal ciliary body, iris, and/or peripheral retina. MCOA syndrome is highly prevalent in the Rocky Mountain Horse but the disease is not limited to this breed. Affected horses most often have a Silver coat color; however, a pleiotropic link between these phenotypes is y...
Bitew M, Andargie A, Bekele M, Jenberie S, Ayelet G, Gelaye E.A cross-sectional serological survey was undertaken in selected districts of different agro-ecology of Jimma zone (Dedo, Yebu, Seka, Serbo, and Jimma town) from November 2009 to February 2010 to determine the seroprevalence of African horse sickness virus and associated risk factors of the disease. Two hundred seventy-four equids (189 horses, 43 mules, and 47 donkeys) with a history of non-vaccination for at least 2 years were selected randomly from the above areas. Sera samples were collected and assayed for the presence of specific antibody against African horse sickness virus using blocking...
Cruz FS, Carregaro AB, Machado M, Antonow RR.This study investigated the sedative, cardiopulmonary, and gastrointestinal effects produced by buprenorphine and xylazine given in combination to horses. Six healthy adult horses underwent 4 randomized treatments, with an interval of 1 wk between treatments. A control group was given a saline solution intravenously (IV) and the experimental groups received buprenorphine [10 μg/kg bodyweight (BW)] in combination with 1 of 3 different doses of xylazine: 0.25 mg/kg BW (BX25), 0.50 mg/kg BW (BX50), or 0.75 mg/kg BW (BX75), all of them by IV. Cardiopulmonary parameters were evaluated for 120 min ...
Franson JC, Hofmeister EK, Collins GH, Dusek RJ.We screened 1,397 feral horses (Equus caballus) on Sheldon National Wildlife Refuge, Nevada, United States, for IgM and IgG against flavivirus during 2004-2006, 2008, and 2009. Positive serum samples were tested for neutralizing antibodies to West Nile virus (WNV) and St. Louis encephalitis virus (SLEV). One animal was positive for antibody against WNV in 2004, but all others tested in 2004-2006 were negative. In 2008 and 2009, we found evidence of increasing seropositive horses with age, whereas seroprevalence of WNV decreased from 19% in 2008 to 7.2% in 2009. No horses were positive for anti...
Coomer RP, Fowke GS, McKane S.To report the technique and results of cheek teeth repulsion in standing, sedated horses. Methods: Case series. Methods: Horses (n = 12), ponies (6). Methods: Medical records (2006-2009) of horses that had cheek tooth repulsion while standing were reviewed. Inclusion criteria included: maxillary or mandibular cheek tooth disease diagnosed by clinical and radiographic examination where attempted oral extraction failed necessitating repulsion. Horses were sedated and a local nerve block performed. Intraoperative radiographs facilitated instrument positioning and ensured repulsion of all dental r...
Rezende ML, Wagner AE, Mama KR, Ferreira TH, Steffey EP.To determine effects of a continuous rate infusion of lidocaine on the minimum alveolar concentration (MAC) of sevoflurane in horses. Methods: 8 healthy adult horses. Methods: Horses were anesthetized via IV administration of xylazine, ketamine, and diazepam; anesthesia was maintained with sevoflurane in oxygen. Approximately 1 hour after induction, sevoflurane MAC determination was initiated via standard techniques. Following sevoflurane MAC determination, lidocaine was administered as a bolus (1.3 mg/kg, IV, over 15 minutes), followed by constant rate infusion at 50 μg/kg/min. Determination...
Gussekloo SW, Lankester J, Kersten W, Back W.To determine the effect of differences in structural and mechanical tendon properties on functionality of the passive stay apparatus in horses. Methods: 5 forelimbs each from nondwarf Friesians, dwarf Friesians, and ponies. Methods: Harvested forelimbs were loaded to test the passive stay apparatus. Tendons that stabilize the distal portion of the limb (superficial digital flexor tendon, deep digital flexor tendon, and tendo interosseus [suspensory ligament]) were isolated, and force-elongation data were obtained. Bone lengths, initial tendon lengths, and initial tendon cross-sectional areas w...
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...
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 (...
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...
Smyth JD.The genetics of speciation in the genus Echinococcus are briefly discussed. As the organism is a hermaphrodite and multiplies asexually in the larval stage, the genetic mechanism for the ready production of new strains is inherent in the life-cycle. Some biological, biochemical and nutritional differences between the horse and sheep strains are examined. The sheep strain may be grown to sexual maturity, in vitro, in a diphasic system; the horse strain fails to grow in such a system. Differences have also been demonstrated between the soluble proteins of the two strains. The sheep strain is inf...
de la Rúa-Domènech R, Wiedmann M, Mohammed HO, Cummings JF, Divers TJ, Batt CA.The cDNA encoding the equine copper/zinc superoxide dismutase (SOD1) was cloned from leukocyte total RNA from healthy horses and its nucleotide (nt) sequence was determined. We further sequenced the SOD1 gene from 16 horses diagnosed with equine motor neuron disease (EMND) and eight unrelated, clinically normal horses to determine if this disease, similar to amyotrophic lateral sclerosis (ALS) in humans, is linked to SOD1 mutations. The 465-bp SOD1 coding region in the horse encodes 153 amino acid (aa) residues. Equine SOD1 exhibited 81.8 and 79.9% sequence identity to the human homolog at the...
Schvartz G, Epp T, Burgess HJ, Chilton NB, Lohmann KL.To investigate the agreement between available serologic tests for the detection of antibodies against Anaplasma phagocytophilum and Borrelia burgdorferi, 50 serum samples from horses of unknown clinical status and at low risk for infection were tested. In addition to a point-of-care enzyme-linked immunosorbent assay (pocELISA), the evaluated tests included 2 indirect fluorescent antibody tests (IFATs) for antibodies against A. phagocytophilum and an IFAT, an ELISA confirmed with Western blot, and the Lyme multiplex assay for antibodies against B. burgdorferi. For each pair-wise comparison bet...
Tolleson DR, Teel PD, Stuth JW, Strey OF, Welsh TH, Carstens GE.Anti-tick treatments are often applied concurrent to routine livestock management practices with little regard to actual infestation levels. Prescription treatments against ticks on grazing cattle would be facilitated by non-invasive detection methods. One such method is fecal near infrared spectroscopy (NIRS). Four studies utilizing cattle (Bos spp.) and one with horses (Equus caballus) fed varying diets and infested with either Amblyomma americanum, A. maculatum, A. cajennense or Dermacentor albipictus were conducted to determine the ability of fecal NIRS to identify samples from animals wit...
Tydén E, Tallkvist J, Tjälve H, Larsson P.P-glycoprotein (P-gp) is an important drug transporter, which is expressed in a variety of cells, such as the intestinal enterocytes, the hepatocytes, the renal tubular cells and the intestinal and peripheral blood lymphocytes. We have studied the localization and the gene and protein expression of P-gp in these cells in horse. In addition we have compared the protein sequence of P-gp in horse with the protein sequences of P-gp in several other species. Real time RT-PCR and Western blot showed gene and protein expression of horse P-gp in all parts of the intestines, but there was no strict cor...
Svalastoga E, Smith M.The subchondral bone pressure in the navicular bone of horses with navicular disease is compared with corresponding pressures in normal horses. An increased intraosseous pressure and a lengthened pressure drop time was demonstrated in patients with navicular disease, which indicates the existence of a venous stasis. Compared with similar investigations in humans with arthrosis it is concluded that navicular disease is a condition resembling arthrosis. The classical clinical symptoms are explained as an expression of resting pains. Treatments are suggested which theoretically can render the pat...
Cabrera AMZ, Soto MJC, Aranzales JRM, Valencia NMC, Gutiérrez MPA.Information on performance indices in Paso horses is scarce. Field exercise tests are necessary to recreate the exertion that occurs during training and competition. To describe blood lactate concentrations and heart rates of untrained Colombian Paso horses (CPHs) in response to a field exercise test. A 30-minutes-long standardized field exercise test was carried out on 11 untrained adult CPHs of both sexes. Blood lactate concentration (BLConc) and heart rate (HR) were measured before, during each step of the test, and at recovery. The BLConc and HR were used to calculate the HR at which a BLC...
Macieira S, Lussier J, Bédard C.Glanzmann thrombasthenia (GT) is characterized by a defect of platelet aggregation. This autosomal recessive genetic disorder is caused by an abnormality of the platelet glycoprotein receptors alpha IIb or beta III. Recently, we identified a horse with clinical and pathological features of GT. The aim of this study was to describe this case of GT at the molecular level. A point mutation from G to C in exon 2 of ITGA2B causing a substitution of the expected amino acid arginine 72 (Arg(72)) by a proline (Pro(72)) was encountered. This amino acid change may result in abnormal structural conformat...
Bampidis V, Azimonti G, Bastos ML, Christensen H, Fašmon Durjava M, Kouba M, López-Alonso M, López Puente S, Marcon F, Mayo B, Pechová A....Following a request from the European Commission, the EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of an essential oil from leaves, stalks and twigs of (L.) J. Presl (cassia leaf oil) when used as a sensory additive (flavouring) in feed and water for drinking for all animal species. Owing to the presence of styrene in cassia leaf oil, the FEEDAP Panel is not in the position to conclude for long-living animals and animals for reproduction. For 'short-living' animals, the FEEDAP Panel conc...
