Veterinary medicine for horses encompasses the study and application of medical practices to diagnose, treat, and prevent diseases in equine species. This field involves a comprehensive understanding of equine anatomy, physiology, pathology, and pharmacology. Veterinary practitioners employ a range of diagnostic tools and therapeutic interventions to address health issues in horses, including lameness, gastrointestinal disorders, respiratory conditions, and infectious diseases. Preventative care, such as vaccination and deworming programs, is also a significant aspect of equine veterinary medicine. This page gathers peer-reviewed research studies and scholarly articles that explore various aspects of veterinary medicine as it pertains to horses, including advancements in diagnostic techniques, treatment protocols, and preventive health strategies.
Pirie RS, McLachlan G, McGorum BC.Currently, heaves is investigated by exposing susceptible horses to dusty hay. Consequently, the response will be dependent on the organic dust content and composition of the hay. It was hypothesised that the use of a hay dust suspension (HDS) would reduce the variability of the challenge and therefore standardise experimental protocols. Furthermore, analysis of HDS would also permit further investigation of the organic dust components responsible for the response. Three hay dust suspensions (HDS-1, 2 and 3) were prepared for use in the diagnosis and investigation of heaves. HDS were produced ...
Pirie RS, Collie DD, Dixon PM, McGorum BC.To evaluate inhaled hay dust suspensions (HDS) as a tool for the diagnosis and investigation of heaves, the pulmonary inflammatory and functional consequences of inhalation challenge with 3 different HDS were determined in 6 control and 7 asymptomatic heaves horses. Heaves horses given HDS challenge developed the characteristic features of heaves, including airway neutrophilia, obstructive airway dysfunction and mucus hypersecretion. While HDS challenge induced a mild airway neutrophilia in controls, the no-response threshold for controls was greater than that of heaves horses, and there was n...
Lorenzo PL, Liu IK, Carneiro GF, Conley AJ, Enders AC.Epidermal growth factor (EGF) has been shown to have a positive effect during oocyte in vitro maturation in several species. This study was performed to establish the capacity of equine oocytes to undergo nuclear maturation in the presence of EGF and to localise its receptor in the equine ovary by immunohistochemical methods. Oocytes were obtained by aspiration and subsequent scraping from equine follicles (15-25 mm diameter) and cultured in 3 different treatment groups for 36 h: control Group (modified TCM 199 with 0.003% BSA), EGF Group (TCM-199 supplemented with 50 ng/ml EGF) and EMS Group ...
Pirie RS, Dixon PM, McGorum BC.To investigate the relative importance of inhaled particulates and soluble components in the response to inhaled hay dust suspension (HDS), heaves (previously termed chronic obstructive pulmonary disease; n = 7) and control (n = 6) horses were given inhalation challenges with whole and fractionated HDS. Fractionation was achieved by centrifugation to yield supernatant (SUP) and particulate debris. The particulates were then washed repeatedly in saline to produce a washed particulate (WP) fraction which comprised mainly fungal spores, and a wash fraction (WF) which comprised saline and soluble ...
Kolm-Stark G, Wagner R.Icelandic horses in Austria are commonly affected by an allergic inflammatory skin disease recurring during the summer seasons, which shares characteristic features with Culicoides hypersensitivity. However, the causative agents have not yet been identified. Therefore, intradermal skin testing (IDST) with a standardised extract of Culicoides variipennis and 21 other allergens relevant within Austria was performed in 81 Icelandic horses. All horses included into the study were treated regularly with ivermectin and had no history of administration of anti-inflammatory drugs. Forty-three of these...
Shearman JP, Hamlin MJ, Hopkins WG.Human athletes taper or reduce their training load before a race to enhance performance, apparently because recovery from the effects of fatigue occurs faster than the loss of fitness from the reduced training. However, there appear to be no previous studies of tapering of equine athletes. Our aim in the present study was, therefore, to investigate the efficacy of tapering with Standardbred pacers. We determined the effect of repeated cycles of tapered training on performance of Standardbred pacers. After 8 weeks of jogging and 3 x 2 week cycles of pace work, 19 horses were randomised to a tap...
Bousquet-Melou A, Bernard S, Schneider M, Toutain PL.Marbofloxacin is a fluoroquinolone antibiotic expected to be effective in the treatment of infections involving gram-negative and some gram-positive bacteria in horses. In order to design a rational dosage regimen for the substance in horses, the pharmacokinetic properties of marbofloxacin were investigated in 6 horses after i.v., subcutaneous and oral administration of a single dose of 2 mg/kg bwt and the minimal inhibitory concentrations (MIC) assessed for bacteria isolated from equine infectious pathologies. The clearance of marbofloxacin was mean +/- s.d. 0.25 +/- 0.05 l/kg/h and the termi...
Dyer J, Fernandez-Castaño Merediz E, Salmon KS, Proudman CJ, Edwards GB, Shirazi-Beechey SP.Dietary carbohydrates, when digested and absorbed in the small intestine of the horse, provide a substantial fraction of metabolisable energy. However, if levels in diets exceed the capacity of the equine small intestine to digest and absorb them, they reach the hindgut, cause alterations in microbial populations and the metabolite products and predispose the horse to gastrointestinal diseases. We set out to determine, at the molecular level, the mechanisms, properties and the site of expression of carbohydrate digestive and absorptive functions of the equine small intestinal brush-border memb...
Sun Y, Chen H, Kandel R, Hurtig M.Lesions in cartilage of equine weightbearing joints commonly result in lameness. Cell-based resurfacing techniques are currently being developed for human and veterinary applications. Biopsies of stifle joint cartilage (1 g) were harvested aseptically and chondrocytes were isolated by sequential enzyme digestion. The cells were grown in vitro on filter inserts. Analysis of cultures 8 weeks later showed that the cells had accumulated extracellular matrix and formed a continuous layer of cartilagenous tissue as determined histologically. The cells maintained their phenotype as they synthesised t...
Carretero M, Rodríguez C, San Andrés MI, Forés P, de Lucas JJ, Nieto J, Waxman S, San Andrés MD, González F.The pharmacokinetic behaviour of marbofloxacin, a new fluoroquinolone antimicrobial agent developed exclusively for veterinary use, was studied in mature horses (n = 5) after single-dose i.v. and i.m. administrations of 2 mg/kg bwt. Drug concentrations in plasma were determined by high performance liquid chromatography (HPLC) and data obtained were subjected to compartmental and noncompartmental kinetic analysis. This compound presents a relatively high volume of distribution (V(SS) = 1.17 +/- 0.18 l/kg), which suggests good tissue penetration, and a total body clearance (Cl) of 0.19 +/- 0.042...
Glass K, Wood JL, Mumford JA, Jesset D, Grenfell BT.This paper demonstrates that a simple stochastic model can capture the features of an epidemic of equine influenza in unvaccinated horses. When the model is modified to consider vaccinated horses, we find that vaccination dramatically reduces the incidence and size of epidemics. Although occasional larger outbreaks can still occur, these are exceptional. We then look at the effects of vaccination on a yard of horses, and in particular at the relationship between pre-challenge antibody level and quantity of virus shed when challenged with the virus. While on average, a high antibody level impli...
Germanà A, Cassata R, Cristarella S, Scirpo A, Muglia U.The three-dimensional architecture of the myosalpinx in the mare was investigated by means of scanning electron microscopy (SEM) after removal of interstitial connective tissue with NaOH digestion. In the extramural portion of the tubo-uterine junction (TUJ), isthmus, and ampulla, the myosalpinx architecture is represented by a unique muscular structure which runs from the mesosalpinx to the base of the inner mucous folds. This unique muscular structure consists mainly of bundles of muscular fibers independent of one another, which show a multiple spatial arrangement and form a complex network...
Fernández-Távora L, Rico P, Martín S.This open clinical study was designed to investigate the occurrence of adverse reactions of specific immunotherapy (SIT) with horse dander and to recognize signs of efficacy regarding horse-induced cutaneous and respiratory symptoms. Methods: Twenty-four patients attending our Outpatient Clinic in Huelva (Spain) with horse-induced allergy were selected for receiving a standardized extract of horse dander (Alutard SQ). Results: Local and systemic reactions (five adverse reactions in four patients) were observed during the induction phase of treatment when administering the doses with the highes...
Martinelli MJ, Eurell J, Les CM, Fyhrie D, Bennett D.Although there are many studies in the equine literature focused on articular diseases and the aetiology of osteoarthritis, few have concentrated on normal articular structures and how they change with age. The objective of this investigation was to study the thickness and morphology of the calcified cartilage layer of the distal metacarpus over a range of ages. A parasagittal slab of bone was sectioned from the region of sesamoid contact on the medial condyle of the metacarpi from 34 horses. The slab of bone was preserved, dehydrated and embedded, undecalcified, in methylmethacrylate and then...
Pickles K, Pirie RS, Rhind S, Dixon PM, McGorum BC.Bronchoalveolar lavage fluid (BALF) samples are often subject to time delays, possibly with temperature fluctuations, between collection and processing. The aim of this study was to evaluate the effects of time, temperature and 2 different fixatives on equine BALF cytology, in order to develop guidelines for optimal equine BALF storage conditions. Total nucleated cell count (TCC), differential cell counts (DCC), absolute cell counts (ACC), cell viability, cell morphology and bacterial growth of BALF samples stored at 4, 18 (+/- addition of formalin- or alcohol-based fixatives) and 38 degrees C...
Pickles K, Pirie RS, Rhind S, Dixon PM, McGorum BC.The aim of this study was to develop a diagnostically useful smear method for preparation of equine bronchoalveolar lavage fluid (BALF) for use by practitioners. A smear method for equine BALF preparation which included the addition of serum was developed, and cell morphology, differential cell counts (DCC) and repeatability of counting DCC compared with those of cytocentrifuged BALF preparations. BALF samples (n = 21) were collected from 5 control horses and 5 heaves-susceptible horses. Smear preparations of BALF produced smaller, darker, staining cells, making cytological identification more...
Muylle S, Simoens P, Lauwers H.The objective of this study was to examine the diameter, extent, orientation and contents of dentinal tubules in order to validate the hypothesis of pigment penetration into the dental star of equine incisival occlusal surfaces. The time of appearance and the configuration of the dental star on the incisival occlusal surface are macroscopically visible features that, along with other more reliable parameters, are used for the determination of horses' age. Although dental stars are an integral part of the equine incisor occlusive surface, the exact nature and microstructure of the dental star a...
Faber M, Johnston C, van Weeren PR, Barneveld A.We tested the hypothesis that repeatability of a standardised protocol for quantifying back kinematics is sufficiently high not to prevent its use in the clinical evaluation of horses with back problems. We investigated the extent to which differences between laboratories may affect the results when a standardised protocol is used. As a clinical tool, movement analysis techniques are helpful for the objective and quantitative assessment of kinematics. Knowledge about the repeatability of the kinematic data is very important. The present study investigates the repeatability of back kinematics i...
Toutain PL, Lassourd V.The current performance of analytical techniques used for drug control in horses lead the Regulatory Authorities to decide whether trace levels of drugs legitimately used for therapeutic medication should or should not be reported. Here, we propose a well-ordered and nonexperimental pharmacokinetic/pharmacodynamic approach for the determination of irrelevant drug plasma (IPC) and urine concentrations (IUC). The published plasma clearance is used to transform an effective (marketed) dose into an effective concentration (EPC). EPC is transformed into an IPC by applying a safety factor (SF). This...
Lopes MA, White NA.Parenteral nutrition is advocated for sick foals and horses, although there is no report which has critically evaluated its benefits in this species. Therefore, the hypothesis that parenteral nutrition (PN) is beneficial for horses with severe gastrointestinal disease was investigated in a retrospective study. Records from 79 treatment courses in horses with gastrointestinal disease were reviewed for the years 1992-2000. The fatality rate (48.1%) was attributed to the severity of the primary disease. Complications due to PN were recorded and hyperglycaemia was the most common complication asso...
Murray RC, Znaor N, Tanner KE, DeBowes RM, Gaughan EM, Goodship AE.Dorsal carpal osteochondral injury is a major cause of lameness in horses undergoing high intensity training. Intra-articular corticosteroid treatment is used commonly to manage exercise-associated articular pain, but its use remains highly controversial in the equine athlete. This project, therefore, aimed to compare the mechanical properties of intra-articular MPA and diluent-treated middle carpal subchondral and cancellous bone in horses undergoing a short-term treadmill exercise programme. It was hypothesised that subchondral and cancellous bone mechanical properties are influenced by intr...
Wilmink JM, van Herten J, van Weeren PR, Barneveld A.In accidental wounds, trauma and infection can result in dehiscence of primarily closed wounds and in sequestrum formation when cortical bone is exposed. In experimental studies, it has been shown that second intention healing is faster and occurs with less complications in ponies than in horses. Also, a greater initial inflammatory response was seen in ponies. Based on these experimental data, it was hypothesised that accidental wounds in ponies would heal with a lower incidence of wound dehiscence and/or sequestrum formation compared to horses. A retrospective study of 89 ponies and 422 hors...
Peroni DL, Stanley S, Kollias-Baker C, Robinson NE.Based on its efficacy for the treatment of human asthma, the corticosteroid prednisone is commonly used in horses for treatment of recurrent airway obstruction. However, recent studies have failed to show any benefit of prednisone tablets for the treatment of this condition. The purpose of this study was to determine why oral prednisone has poor efficacy for the treatment of heaves in horses. In a crossover study, 5 horses were given the following treatments: prednisone tablets, prednisone liquid, prednisolone tablets, prednisolone liquid and i.v. prednisolone sodium succinate (positive contro...
Dyson SJ.The purposes of this study were to investigate the ultrasonographic appearance of the patellar ligaments in clinically normal horses and to describe the clincical features, diagnosis and outcome of patellar ligament injury. The medial, middle and lateral patellar ligaments of 5 Thoroughbred and 5 Warmblood horses, free from lameness and in full work, were examined ultrasonographically. The ligaments were all of uniform echogenicity and each ligament was fairly consistent in its shape. The size of the ligaments of the Warmblood horses tended to be bigger than the lighter bodyweight Thoroughbred...
Lawler DF, Brazil TJ, Dagleish MP, Watson ED.This study investigated the chemotactic activity of equine CL at different stages of the oestrous cycle. The purpose of this was to ascertain whether luteal tissue itself contributes to the massive influx of leucocytes around the time of natural and induced luteal regression. Corpora lutea were collected at different stages of dioestrus and after treatment with PGF2alpha. Culture medium harvested after incubation of luteal tissue for 20 h was chemotactic for both polymorphonuclear and mononuclear cells in late dioestrus (before functional regression) as well as after natural and induced luteal...
Zhang Y, Xu WW, Guo DH, Liu ZX, Duan H, Su X, Fu X, Yue DM, Gao Y, Wang CR.The equine pinworm Oxyuris equi (Nematoda: Oxyuridomorpha) is the most common horse nematode, has a worldwide distribution, and causes major economic losses. In the present study, the complete O. equi mitochondrial (mt) genome was sequenced, and the mt genome structure and organization were compared with those of other closely related pinworm species, Enterobius vermicularis and Wellcomia siamensis. The O. equi mt genome is a 13,641-bp circular DNA molecule that encodes 36 genes (12 protein-coding genes, 22 tRNAs, and two rRNAs) and one non-coding region, which is slightly shorter than that ...
Gorgas D, Luder P, Lang J, Doherr MG, Ueltschi G, Kircher P.Nuclear bone scintigraphy is commonly used in the diagnosis of sacroiliac disease in horses. The aim of the present retrospective study was to determine if there was an association between radiopharmaceutical uptake pattern and radiographic appearance of the sacroiliac region in horses. Seventy-nine horses undergoing bone scintigraphy with Tc-99 m-HDP and radiography of the pelvis because of lameness or poor performance were studied. Subjective and semiquantitative methods were used to characterize and compare radiopharmaceutical uptake between horses. Ventrodorsal radiographs of the region we...
Crabb BS, Studdert MJ.A series of truncated equine herpesvirus 1 (EHV1) glycoprotein C (gC) molecules was examined for use as serodiagnostic antigens for EHV1 and EHV4. Small regions of EHV1 glycoprotein C, an immunodominant EHV1 glycoprotein, were expressed in Escherichia coli as glutathione S-transferase (GST) fusion proteins using the bacterial expression vector pGEX-2T. Sera obtained from horses, including sera from specific-pathogen-free (SPF) foals, following exposure to either EHV1, EHV4 or both viruses were used. Several of the fusion proteins were shown to encompass EHV1 specific epitopes while others enco...
Delesalle C, van Acker N, Claes P, Deprez P, de Smet I, Dewulf J, Lefebvre RA.Prokinetic drugs used to treat gastrointestinal ileus in man have equivocal results in horses. In man, prokinetic drugs have 5-hydroxytryptamine4(5-HT4) receptors as their target, but little is known about the 5-HT-receptor subtypes in the equine small intestine. Objective: Functional and immunohistochemical identification of the serotonin receptor subtype(s) responsible for the 5-HT induced contractile response in the equine circular jejunum. Methods: Isometric organ-bath recordings were carried out to assess spontaneous and drug-evoked contractile activity of equine circular jejunum. Histolo...
Seo HJ, Truong AT, Kim KH, Lim JY, Min S, Kim HC, Yoo MS, Yoon SS, Klein TA, Cho YS.The horse industry has grown rapidly as a leisure industry in the Republic of Korea (ROK) in parallel with an increased demand for equestrian activities. As a result, there has been an increase in horse breeding and equestrian population and potential exposure to ticks and their associated pathogens. To provide a better understanding of the potential disease risks of veterinary and medical importance, a study was conducted to determine the geographical distribution and diversity of ticks collected from horses and vegetation associated with horse racetracks/ranches throughout the ROK. This incl...
Boivin R, Vargas A, Cano P, Lavoie JP.Recurrent inflammation in severe equine asthma causes a remodeling of the airways leading to incompletely reversible airway obstruction. Despite the improvement of clinical signs and lung function with glucocorticoids (GC), inflammation, translated by an increased percentage of neutrophils, persists in the airways. Regulatory T cells (Treg) have been shown to have anti-inflammatory properties and play an important role in balancing the immune response by suppressing effector lymphocyte activity. However, interactions between Treg, neutrophils and glucocorticosteroids in vivo are unclear, parti...
Rainger JE, Dart CM, Perkins NR.To assess the effects of the duration of anaesthesia, position of recumbency, mode of ventilation, anaesthetic drug protocol, patient age and type of surgical procedure on the usefulness of capnometry as a measure of the partial pressure of arterial carbon dioxide (P(a)co(2)) during general anaesthesia in horses. Methods: A prospective study compared the P(a)co(2) values with those of partial pressure of end-tidal carbon dioxide (ETco(2)) in horses anaesthetised for elective or emergency surgical procedures. The difference between P(a)co(2) and ETco(2) (P(a)co(2)- ETco(2)) and the physiologica...
Kimura S, McCoy AM, Boothe DM, Wooldridge AA, Graff E, Hammack SM, Cresci L, Hofmeister E, Lascola KM.To describe misoprostol pharmacokinetics and anti-inflammatory efficacy when administered orally or per rectum in endotoxin-challenged horses. Methods: 6 healthy geldings. Methods: A randomized 3-treatment crossover design was performed with a minimum washout period of 28 days between treatment arms. Prior to endotoxin challenge (lipopolysaccharide, 30 ng/kg IV over 30 minutes), horses received misoprostol (5 µg/kg once) per os (M-PO) or per rectum (M-PR) or water as control (CON). Clinical parameters were evaluated and blood samples obtained to measure plasma misoprostol free acid concentrat...
Four horses were evaluated because of hind limb lameness. Two had a distinct gait abnormality at the walk characterized by lateral rotation of the point of the calcaneus and medial rotation of the toe during the stance phase. Nuclear scintigraphy revealed a focal area of intense radioisotope uptake in the caudodistal aspect of the femur in all 4 horses, and 3 of the horses had a corresponding proliferative reaction on the caudodistal cortex of the femur on radiographs. In all 4 horses, a diagnosis of injury to the origin of the gastrocnemius muscle was made. Three of the horses returned to ath...
Hikasa Y, Takase K, Ogasawara S.The effects of sevoflurane-oxygen anaesthesia at a light-surgical depth on clinically important features were evaluated in spontaneously breathing horses that received atropine, xylazine, and guaifenesin-thiopental. Mean end-tidal concentrations of sevoflurane ranged from 1.6 to 2.3% during 90 min maintenance. Recovery from anaesthesia was extremely rapid and smooth. Heart rates did not significantly change after anaesthesia. Arrhythmia was not observed. Mean arterial pressure (mean +/- SD) ranged from 86 +/- 17 to 98 +/- 5 mmHg during anaesthesia. Minute ventilation was low due to decreased r...
Blue JT, Dinsmore RP, Anderson KL.Three horses developed severe, immune-mediated hemolytic anemia after treatment with penicillin. The horses had positive direct antiglobulin (Coombs) tests and high titers of IgG antibody that agglutinated penicillin-coated equine red cells. Two of the horses were tested for antibodies to autologous red cell antigens; autoantibodies were not present. Titers of antipenicillin antibody decreased after penicillin was discontinued but IgG antibody was detectable months after recovery. One of the horses was challenged with penicillin; antibody titer increased slightly, but anemia did not develop. A...
Watkins JP, Taylor TS, Schumacher J, Taylor JR, Gillis JP.The records of 35 horses with Grade 3 or 4 rectal tears, presented to the Veterinary Medical Center at Texas A & M University over a five year period, were reviewed. Grade 3 tears were sub-classified according to whether the remaining tissue was serosa (Grade 3a) or mesorectum (Grade 3b). Five horses were destroyed on presentation and 30 were treated by primary suture closure (8 horses), faecal diversion alone (9 horses) or in combination with suture closure (11 horses) and packing of the tear with medicated gauze sponges (two horses). Faecal diversion was achieved with a temporary indwell...
Sevcik C, Díaz P, D'Suze G.Specific immunoassays were developed to detect anti-horse, anti-chicken and anti-bovine immunoglobulins in human IgG preparations. Three samples of 5% human IgG for intravenous use ("Inmunoglobulina G Endovenosa al 5%"(trade mark), Quimbiotec CA), were studied. All samples were produced from pools of >2500 plasma units from different donors. One sample was produced from an only Venezuelan plasma pool (2660 donors) and the other two were produced from a 1:1 blend of Venezuelan and Canadian plasma pools. The amounts of human IgG detected were 0.017 (0.015,0.020) mg/ml (n=18) against horse IgG...
Field JR, Jeffcott LB.Laminitis is an important condition in horses and ponies, not just because of the seriousness of the clinical signs and systemic changes involved, but because of the potentially poor prognosis and likelihood of recurrence. Laminitis is particularly prevalent in ponies and involves a multiplicity of aetiological factors. Fat ponies and those having previously suffered laminitis were found to be far more intolerant to oral glucose loading (1 g/kg bwt) than normal ponies or Standardbred horses. These ponies also exhibited a far greater response in plasma insulin levels after glucose loading. Insu...
McNamara JP.Departments of animal sciences must be relevant to a society in which a small number of people can raise almost all the food animal products needed. The declining number of people involved in animal agriculture has decreased enrollment of students interested in food animals in many departments of animal science. However, several departments welcomed students from a diverse background and began research on animals other than food animals. In many states, the undergraduate enrollment is made up primarily of students interested only in companion animals. A benefit of this is that we have recruite...
Guan F, Uboh CE, Soma LR, Birks EK, Teleis D, Rudy JA, Watson AO, Tsang DS.A reliable and sensitive method for the extraction and quantification of phenytoin (5,5'-diphenylhydantoin), its major metabolite, 5-(p-hydroxyphenyl)-5-phenylhydantoin (p-HPPH) and minor metabolite, 5-(m-hydroxyphenyl)-5-phenylhydantoin (m-HPPH) in horse urine and plasma is described. The method involves the use of solid-phase extraction (SPE), liquid-liquid extraction (LLE), enzyme hydrolysis (EH) and high-performance liquid chromatography (HPLC). The minor metabolite, 5-(m-hydroxyphenyl)-5-phenylhydantoin (m-HPPH) was not present in a reliably quantifiable concentration in all samples. The ...
Adair S, Baus M, Bell R, Boero M, Bussy C, Cardenas F, Casey T, Castro J, Davis W, Erskine M, Farr R, Fischer A, Forbes B, Ford T, Genovese R....No abstract available
Landoni MF, Lees P.The bioavailability of S(+) and R(-) ketoprofen (KTP) in six horses was investigated after oral administration of the racemic (rac) mixture. Two oral formulations were studied, an oil-based paste containing micronised rac-KTP and powder from the same source in hard gelatin capsules, each at a dose rate of 2.2 mg/kg. For the oil-based paste two feeding schedules were used; horses were either allowed free access to food or access to food was restricted for 4 h before and 5 h after dosing. The drug in hard gelatin capsules was administered to horses with restricted access to food. After intraveno...
Rossignol F, Perrin R, Desbrosse F, Elie C.To compare in vitro the load necessary for a partial and complete rupture of the muscular process arytenoid cartilage when a suture prosthesis is positioned by a bone trocar versus a trocar point needle and to compare failure mode. Methods: Experimental using cadaver specimens. Methods: Larynges from 18 Thoroughbred race horses, aged 2-20 years. Methods: Arytenoid cartilages were separated randomly into 2 groups: group 1-suture prosthesis inserted directly through the muscular process using a curved trocar point needle and group 2-suture passed through a hole predrilled with a 3 mm bone trocar...
Fjordbakk CT, Revold T, Goodwin D, Piercy RJ.The pathogenesis of bilateral dynamic laryngeal collapse associated with poll flexion (DLC) of horses is unknown but might be associated with intrinsic laryngeal muscle weakness. Objective: To investigate histopathological characteristics of the cricoarytenoideus dorsalis, the cricothyroid (CT) and the cricoarytenoideus lateralis muscles in DLC-affected horses and compare these with unaffected controls. Our hypotheses were that evidence of neurogenic atrophy of the CT or cricoarytenoideus dorsalis muscles would be found in DLC-affected horses and that observed changes would be symmetrically (l...
Nakayama SM, Ikenaka Y, Hayami A, Mizukawa H, Darwish WS, Watanabe KP, Kawai YK, Ishizuka M.Research on drug metabolism and pharmacokinetics in large animal species including the horse is scarce because of the challenges in conducting in vivo studies. The metabolic reactions catalyzed by cytochrome P450s (CYPs) are central to drug pharmacokinetics. This study elucidated the characteristics of equine CYPs using diazepam (DZP) as a model compound as this drug is widely used as an anesthetic and sedative in horses, and is principally metabolized by CYPs. Diazepam metabolic activities were measured in vitro using horse and rat liver microsomes to clarify the species differences in enzy...
Sullins KE, McIlwraith CW, Yovich JV, MacHarg MA, Fessler J.Unilateral ureteral ectopia was diagnosed in three-year-old and 10-month-old fillies exhibiting urinary incontinence since birth. In one case reimplantation of the ureter onto the bladder was planned but considered to be impractical intra-operatively. Unilateral nephrectomy was performed successfully in both cases which alleviated the urinary incontinence. Both horses had normal urinary function postoperatively and became healthy, serviceable animals.
Wright BD, Hildebrand SV.To compare arterial oxygen and carbon dioxide tensions in apneic and spontaneously ventilating horses recovering from anesthesia. Methods: Randomized clinical trial. Methods: Forty-two healthy horses averaging 466 ± 106 kg and 6 ± 5 years of age. Methods: Anesthetized horses undergoing a variety of surgical procedures and receiving positive pressure ventilation (IPPV) were divided into two equal groups. One group was allowed to return to spontaneous ventilation prior to disconnection from the anesthetic circuit (weaned). The other group remained apneic during transport to a recovery stall. A...
Wernery U, Chan E, Raghavan R, Teng JLL, Syriac G, Siu SY, Joseph M, Yeung ML, Jia L, Cai JP, Chiu TH, Lau SKP, Woo PCY.Glanders is a highly contagious and potentially serious disease caused by Burkholderia mallei, a Tier 1 select agent. In this study, we raised a monoclonal antibody (mAb) against the lipopolysaccharide (LPS) of B. mallei and developed a competitive enzyme-linked immunosorbent assay (cELISA) for B. mallei infection. Using the titrated optimal conditions of B. mallei-LPS (2 ng) for microtiter plate coating, sample serum dilution at 1:20 and 3.5 ng/μL anti-LPS mAb B5, the cutoff value of the cELISA was determined using serum samples from 136 glanders-free seronegative horses in Hong Kong. All ca...
