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.
Benjelloun A, El Harrak M, Calistri P, Loutfi C, Kabbaj H, Conte A, Ippoliti C, Danzetta ML, Belkadi B.West Nile virus-associated disease is one of the most widespread vector-borne diseases in the world. In Morocco, the first cases were reported in horses in 1996 and the disease re-emerged in 2003 and in 2010. The objective of this work was to study the epidemiological situation of WNV-associated infection in Morocco, by quantifying the seroprevalence of anti-WNV IgM and IgG antibodies in horses in different bioclimatic regions-zones of Morocco in 2011. During the months of May, June and July 2011, 840 serum samples were collected from horses in four regions characterized by different environme...
Schröck C, Eydt C, Geburek F, Kaiser L, Päbst F, Burk J, Pfarrer C, Staszyk C.Allogeneic equine multipotent mesenchymal stromal cells (eMSCs) have been proposed for use in regenerative therapies in veterinary medicine. A source of allogeneic eMSCs might be the bone marrow from euthanized horses. The purpose of this study was to compare characteristics of equine bone marrow derived eMSC (eBM-MSCs) from euthanized horses (eut-MSCs) and from narcotized horses (nar-MSCs). Eut-MSCs and nar-MSCs showed typical eMSC marker profiles (positive: CD44, CD90; negative: CD11a/CD18 and MHCII) and possessed tri-lineage differentiation characteristics. Although CD105 and MHCI expressi...
Echeverria KO, Lascola KM, Giguère S, Foreman JH.Minocycline is commonly used to treat bacterial and rickettsial infections in adult horses but limited information exists regarding the impact of feeding on its oral bioavailability. This study's objective was to compare the pharmacokinetics of minocycline after administration of a single oral dose in horses with feed withheld and with feed provided at the time of drug administration. Six healthy adult horses were administered intravenous (2.2 mg/kg) and oral minocycline (4 mg/kg) with access to hay at the time of oral drug administration (fed) and with access to hay delayed for 2 hr after ...
Liuti T, Reardon R, Dixon PM.Disorders affecting the equine maxillary cheek teeth and paranasal sinuses are relatively common, but limited objective information is available on the dimensions and relationships of these structures in horses of different ages. The aims of this study were to assess age-related changes in the positioning and anatomical relationships of the individual maxillary cheek teeth with the infraorbital canal and maxillary septum and the volumes of the individual sinus compartments. CT and gross examination were performed on 60 normal equine cadaver heads that were aged by their dentition. The intrasin...
Pedersen PJ, Thomsen KB, Flak JB, Tejada MA, Hauser F, Trachsel D, Buhl R, Kalbfleisch T, DePriest MS, MacLeod JN, Calloe K, Klaerke DA.The voltage-gated K-channel K7.1 and the subunit KCNE1, encoded by the KCNQ1 and KCNE1 genes, respectively, are responsible for termination of the cardiac action potential. In humans, mutations in these genes can predispose patients to arrhythmias and sudden cardiac death (SCD). Objective: To characterize equine K7.1/KCNE1 currents and compare them to human K7.1/KCNE1 currents to determine whether K7.1/KCNE1 plays a similar role in equine and human hearts. Methods: mRNA encoding K7.1 and KCNE1 was isolated from equine hearts, sequenced, and cloned into expression vectors. The channel subunits ...
Scheidegger MD, Gerber V, Bruckmaier RM, van der Kolk JH, Burger D, Ramseyer A.This study tested the hypothesis that adrenocortical function would be altered in horses with equine gastric ulcer syndrome (EGUS). Twenty-six sport horses competing at national or international levels in eventing (n=15) or endurance (n=11) were subjected to a gastroscopic examination and an adrenocorticotropic hormone (ACTH) stimulation test. Salivary cortisol concentrations were measured before (baseline) and after (30, 60, 90, 120 and 150min) IV ACTH injection (1μg/kg bodyweight). Within EGUS, two distinct diseases, equine squamous gastric disease (ESGD) and equine glandular gastric diseas...
Jacklin B.Ben Jacklin is equine director and consultant veterinary surgeon at CVS UK. He is a diplomate of the European College of Veterinary Surgeons and an RCVS and ECVS Specialist in equine surgery.
Liu Q, Wang XF, Du C, Lin YZ, Ma J, Wang YH, Zhou JH, Wang X.Integration is an important feature of retroviruses and retrovirus-based therapeutic transfection vectors. The non-primate lentivirus equine infectious anaemia virus (EIAV) primarily targets macrophages/monocytes . Investigation of the integration features of EIAV strains, which are adapted to donkey monocyte-derived macrophages (MDMs), is of great interest. In this study, we analysed the integration features of EIAV in equine MDMs during infection. Our previously published integration sites (IS) for EIAV in fetal equine dermal (FED) cells were also analysed in parallel as references. Sequenc...
The Veterinary recordSeptember 9, 2017
Volume 181, Issue 10 ii doi: 10.1136/vr.j4128
Carslake H.Harry Carslake, equine medicine specialist at the Philip Leverhulme Equine Hospital, Liverpool, reviews a fiveday course on advanced cardiac ultrasound scanning that he completed recently.
Saville WJA, Reed SM, Dubey JP, Granstrom DE, Morley PS, Hinchcliff KW, Kohn CW, Wittum TE, Workman JD.The diagnosis of equine protozoal myeloencephalitis (EPM) relies heavily on the clinical examination. The accurate identification of neurologic signs during a clinical examination is critical to the interpretation of laboratory results. Objective: To investigate the level of agreement between board-certified veterinary internists when performing neurologic examinations in horses. Methods: Ninety-seven horses admitted to the Veterinary Teaching Hospital at The Ohio State University from December 1997 to June 1998. Methods: A prospective epidemiologic research design was used. Horses enrolled in...
Cole R, Taintor J, Hanson R.An adult gelding was evaluated for bilateral intermittent forelimb lameness of approximately 2 years duration. The horse was found to have grade 2/5 upper motor neuron-general proprioception ataxia with no cranial nerve deficits. During radiographic and gross necropsy examinations a novel atlanto-axial malformation of possible congenital etiology was found. Un hongre adulte a été évalué pour une boiterie intermittente de la jambe avant présente depuis environ 2 ans. On a constaté que le cheval avait une ataxie de proprioception générale des motoneurones supérieurs de grade 2/5 sans d...
Mouser VHM, Dautzenberg NMM, Levato R, van Rijen MHP, Dhert WJA, Malda J, Gawlitta D.The implantation of chondrocyte-laden hydrogels is a promising cartilage repair strategy. Chondrocytes can be spatially positioned in hydrogels and thus in defects, while current clinical cell therapies introduce chondrocytes in the defect depth. The main aim of this study was to evaluate the effect of spatial chondrocyte distribution on the reparative process. To reduce animal experiments, an ex vivo osteochondral plug model was used and evaluated. The role of the delivered and endogenous cells in the repair process was investigated. Full thickness cartilage defects were created in equine ost...
Manneveau GB, Robert MP, Tessier C, Bizon-Mercier C.This report describes a rare case of gastric impaction caused by a trichophytobezoar in a foal. This case highlights the difficulty in diagnosing this condition and reports surgical removal via a gastrotomy after failure of medical treatment. Ablation chirurgicale d’un trichophytobézoar gastrique chez un poulain. Ce rapport décrit un rare cas d’obstruction gastrique causé par un trichophytobézoar chez un poulain. Ce cas souligne la difficulté à diagnostiquer cette affection et fait rapport sur l’ablation chirurgicale lors d’une gastrotomie après l’échec du traitement médical...
Ishak GM, Bashir ST, Gastal MO, Gastal EL.Color Doppler ultrasonography was used to study the temporal relationships between pre-ovulatory follicle (POF) and corpus luteum (CL) diameter and blood flow, with systemic progesterone (P4) concentration during two transitional ovulatory seasons in mares. Variables of POF and CL/P4 were evaluated for 6days before and 17days after ovulation, respectively. Evaluations were performed during two consecutive estrous cycles in spring and fall seasons, and during the last estrous cycle of the season. There were significant correlations among POF and CL variables, and P4 concentration that ranged fr...
Tessier L, Côté O, Clark ME, Viel L, Diaz-Méndez A, Anders S, Bienzle D.Severe equine asthma is a naturally occurring lung inflammatory disease of mature animals characterized by neutrophilic inflammation, bronchoconstriction, mucus hypersecretion and airway remodeling. Exacerbations are triggered by inhalation of dust and microbial components. Affected animals eventually are unable of aerobic performance. In this study transcriptomic differences between asthmatic and non-asthmatic animals in the response of the bronchial epithelium to an inhaled challenge were determined. Results: Paired endobronchial biopsies were obtained pre- and post-challenge from asthmatic ...
De Santis M, Contalbrigo L, Borgi M, Cirulli F, Luzi F, Redaelli V, Stefani A, Toson M, Odore R, Vercelli C, Valle E, Farina L.Equine assisted interventions (EAIs) are recently facing an increasing popularity, and are characterized by a wide diversity of practices. However, information on the welfare of animals involved in this kind of activity is often lacking. Horses are highly susceptible to work stressors related to physical constraints and/or to the need to control emotions while interacting with humans. Considerations of the emotional state of horses involved in EAIs have multiple valences: for the safety of humans and animals involved, for the quality and efficacy of interventions, as well as for ethical reason...
Legacki EL, Ball BA, Corbin CJ, Loux SC, Scoggin KE, Stanley SD, Conley AJ.Equine fetuses have substantial circulating pregnenolone concentrations and thus have been postulated to provide significant substrate for placental 5α-reduced pregnane production, but the fetal site of pregnenolone synthesis remains unclear. The current studies investigated steroid concentrations in blood, adrenal glands, gonads and placenta from fetuses (4, 6, 9 and 10 months of gestational age (GA)), as well as tissue steroidogenic enzyme transcript levels. Pregnenolone and dehydroepiandrosterone (DHEA) were the most abundant steroids in fetal blood, pregnenolone was consistently higher bu...
Kosolofski HR, Gow SP, Robinson KA.A retrospective study determined the prevalence of obesity and over-conditioning in horses in Saskatoon, Saskatchewan. Body condition score (BSC) was assessed for 290 horses from the Field Service practice at the Western College of Veterinary Medicine. The median BSC of horses was 6; however, 59 (20.3%) horses were classified as over-conditioned, and 24 (8.3%) as obese. Une étude rétrospective a déterminé la prévalence de l’obésité et du surconditionnement des chevaux à Saskatoon, en Saskatchewan. La note d’état corporel (NEC) a été évaluée pour 290 chevaux à la pratique sur...
Montes-Cortés MG, Fernández-García JL, Martínez-Estéllez MÁH.Equine piroplasmosis is caused by two haemoprotozoan parasites: and . Negative economic impact on international trade has been associated to endemic sites. This is the reason why carrier detection requires reliable diagnostic methods. Various diagnostic modalities can be used alone or in combination including PCR. However, genetic variation of commonly used genes is still of debate. The aim of this research was to sequence the β-tubulin gene of a strain from Spain and to compare it with known β-tubulin sequences. Methods: DNA was isolated from a cryopreserved strain from Spain and acute an...
Pohlin F, Brabender K, Fluch G, Stalder G, Petit T, Walzer C. Ecosystems with seasonal fluctuations in climate and food availability present physiological challenges to resident mammals and may cause "stress." The two predominant physiological responses to stressors are (1) the activation of the hypothalamic-pituitary-adrenal axis and (2) the modulation of the autonomic nervous system. To date, the primary indicator for "stress" in wildlife- and zoo animal research are glucocorticoid levels. By measuring the autonomic regulation of cardiac activity, particularly the vagal tone, heart rate variability (HRV) is presently emerging as a suitable indicator o...
Lorenzett MP, Pereira PR, Bassuino DM, Konradt G, Panziera W, Bianchi MV, Argenta FF, Hammerschmitt ME, Caprioli RA, de Barros CSL, Pavarini SP....Trema micrantha is a tree widely distributed throughout the Americas. The tree produces highly palatable leaves that have been associated with natural poisoning in goats, sheep and horses, in which hepatic necrosis and hepatic encephalopathy have been observed. Objective: This study describes malacia and haemorrhage in the central nervous system (CNS) due to T. micrantha consumption, with minimal to absent hepatic lesions. Methods: Retrospective case series. Methods: A total of 14 horses with a history of neurological signs and spontaneous consumption of T. micrantha leaves were submitted to...
Leahy ER, Holcombe SJ, Hackett ES, Scoggin CF, Embertson RM.Limited data exist describing broodmare longevity and reproductive efficiency after surgical correction of ≥360 degree large colon volvulus (° LCV). Objective: Compare career duration and foals delivered for broodmares before and after ≥360° LCV surgery. Methods: Retrospective case series. Methods: Broodmares registered with The Jockey Club that had surgical correction of ≥360° LCV and survived to hospital discharge at Rood and Riddle Equine Hospital from 1 January 2000 to 31 December 2015 were included. Information was collected from the hospital's medical data base and The Jockey Cl...
Lightbody KL, Matthews JB, Kemp-Symonds JG, Lambert PA, Austin CJ.Anthelmintic resistance combined with limited chemotherapeutic options has prompted a change in approaches to control of equine helminth infections. Targeted selective treatment strategies use diagnostics to reduce anthelmintic use by treating individuals with worm burdens or egg shedding levels above a set threshold. While faecal egg count analysis has limitations for informing tapeworm treatment, a commercially available saliva-based diagnostic test accurately diagnoses horses with tapeworm infection. Objective: Evaluation of a saliva-based diagnostic test to identify horses naturally infect...
Bamford NJ, Sprinkle SB, Cudmore LA, Cullimore AM, van Eps AW, Verdegaal EJMM, Tennent-Brown BS.Snake envenomation is a cause of morbidity and mortality in domestic animals worldwide. The clinical features of crotalid snake (pit viper) envenomation are widely reported and well described in horses but elapid snake envenomation is poorly characterised. Objective: To describe the presentation, clinical and laboratory findings, treatment and outcome of horses with a diagnosis of elapid snake envenomation in Australia. Methods: Retrospective case series. Methods: Medical records of horses with a diagnosis of elapid snake envenomation (2006-2016) at several university and private veterinary pr...
Schoppe C, Hellige M, Rohn K, Ohnesorge B, Bienert-Zeit A.Modern imaging techniques such as computed tomography (CT) and magnetic resonance imaging (MRI) have the advantage of producing images without superimposition. Whilst CT is a well-established technique for dental diagnostics, MRI examinations are rarely used for the evaluation of dental diseases in horses. Regarding equine endodontic therapies which are increasingly implemented, MRI could help to portray changes of the periodontal ligament and display gross pulpar anatomy. Knowledge of age-related changes is essential for diagnosis, as cheek teeth and surrounding structures alter with increasi...
Sarin JK, Rieppo L, Brommer H, Afara IO, Saarakkala S, Töyräs J.Conventional arthroscopic evaluation of articular cartilage is subjective and poorly reproducible. Therefore, implementation of quantitative diagnostic techniques, such as near infrared spectroscopy (NIRS) and optical coherence tomography (OCT), is essential. Locations (n = 44) with various cartilage conditions were selected from mature equine fetlock joints (n = 5). These locations and their surroundings were measured with NIRS and OCT (n = 530). As a reference, cartilage proteoglycan (PG) and collagen contents, and collagen network organization were determined using quantitative ...
Stewart AS, Freund JM, Gonzalez LM.Intestinal epithelial stem cells are critical to epithelial repair following gastrointestinal injury. The culture of intestinal stem cells has quickly become a cornerstone of a vast number of new research endeavours that range from determining tissue viability to testing drug efficacy for humans. This study aims to describe the methods of equine stem cell culture and highlights the future benefits of these techniques for the advancement of equine medicine. Objective: To describe the isolation and culture of small intestinal stem cells into three-dimensional (3D) enteroids in horses without cli...
Aleman M, Weich KM, Madigan JE.Horses are a precocious species that must accomplish several milestones that are critical to survival in the immediate post-birth period for their survival. One essential milestone is the successful transition from the intrauterine unconsciousness to an extrauterine state of consciousness or awareness. This transition involves a complex withdrawal of consciousness inhibitors and an increase in neuroactivating factors that support awareness. This process involves neuroactive hormones as well as inputs related to factors such as cold, visual, olfactory, and auditory stimuli. One factor not previ...
Krägeloh T, Cavalleri JMV, Ziegler J, Sander J, Terhardt M, Breves G, Cehak A.Intestinal absorption of hypoglycin A (HGA) and its metabolism are considered major prerequisites for atypical myopathy (AM). The increasing incidence and the high mortality rate of AM urgently necessitate new therapeutic and/or preventative approaches. Objective: To identify a substance for oral administration capable of binding HGA in the intestinal lumen and effectively reducing the intestinal absorption of the toxin. Methods: Experimental in vitro study. Methods: Substances commonly used in equine practice (activated charcoal composition, di-tri-octahedral smectite, mineral oil and activat...
Geiger SM, Reich E, Böttcher P, Grund S, Hagen J.Biplane high-speed fluoroscopy is a new method for gait analysis of the equine distal extremity. This is the first study validating the noninvasive tracking possibilities (Autoscoping and Scientific Rotoscoping) taking equine anatomy into account. Objective: To determine the resolution with which Autoscoping and Scientific Rotoscoping depict motion of the equine phalanges in comparison to the invasive gold standard marker-based registration. Methods: Comparative ex vivo study. Methods: In 5 distal extremities of slaughtered ponies, 3 or 4 tantalum beads with 1 mm diameter were implanted in e...
Peters-Kennedy J, Lange CE, Rine SL, Hackett RP.Equus caballus papillomavirus 8, a recently discovered virus, has been reported to cause generalised papillomavirus in horses. Objective: To describe a case in which multiple viral plaques, viral papillomas, squamous cell carcinoma (SCC) in situ and invasive squamous cell carcinoma (ISCC) were associated with EcPV8 in a horse. Methods: Case report. Methods: A 16-year-old mixed breed horse presented with dozens of raised crusted papular to nodular lesions over a course of 4 years. Masses had been surgically excised four times and cisplatin beads and emulsion were implanted on three different ...
Cochran JD, Amann RP, Froman DP, Pickett BW.Five experiments evaluated the effects of processing, freezing and thawing techniques on post-thaw motility of equine sperm. Post-thaw motility was similar for sperm frozen using two cooling rates. Inclusion of 4% glycerol extender was superior to 2 or 6%. Thawing in 75 degrees C water for 7 sec was superior to thawing in 37 degrees C water for 30 sec. The best procedure for concentrating sperm, based on sperm motility, was diluting semen to 50 x 10(6) sperm/ml with a citrate-based centrifugation medium at 20 degrees C and centrifuging at 400 x g for 15 min. There was no difference in sperm mo...
Pricking S, Bollwein H, Spilker K, Martinsson G, Schweizer A, Thomas S, Oldenhof H, Sieme H.Accurate determination of the testes volume and prediction of the daily sperm output (DSO) is valuable information for reproductive management of a stallion. The aim of this study was to compare different methods for measuring the testes volume, including caliper, 2D and 3D ultrasound. Special emphasis was on feasibility of 3D volume analysis. First, 22 castrated testes were measured and derived volumes were compared with volumes determined via volume displacement in a graded cylinder with saline solution. Then, during the breeding season, testes sizes of 52 stallions were measured in vivo an...
Schryver HF, Parker MT, Daniluk PD, Pagan KI, Williams J, Soderholm LV, Hintz HF.The voluntary salt consumption of mature unexercised horses was measured weekly for up to 45 weeks. Voluntary intake among horses was quite variable ranging from 19 to 143 g of salt per day and was inversely related to total salt intake (salt in feeds plus voluntary intake). Mean daily voluntary salt consumption was 53 g. Season of the year did not influence voluntary intake. In preference tests which evaluated every two choice combination of 0.2% and 4% NaCl in test diets fed daily for four days, ponies generally preferred diets containing the lower amount of salt. In similar preference studi...
Müller K, König M, Thiel HJ.The tick-borne encephalitis (TBE), also known as early summer meningo-encephalitis, is a geographically limited virus infection transmitted mainly by ticks. The importance of TBE is largely underestimated. The causative agent TBE-Virus (TBEV) is grouped into the genus Flavivirus of the virus family Flaviviridae. Clinical disease including fatal outcomes has been described for men and dogs. With regard to horses only a limited number of case reports is available. In a study performed at the Institute of Virology, Justus-Liebig-University Giessen serum samples from the German endemic region of M...
Stewart S, Southwood LL, Aceto HW.There is disagreement among surgeons over whether jejunoileostomy (JI) or jejunocaecostomy (JC) is the better method of anastomosis following proximal ileal resection. Objective: To compare short- and long-term complications and outcome in horses undergoing jejunojejunostomy (JJ), JI and JC and to test the hypotheses that a higher proportion of horses undergoing JI would have short-term complications and mortality compared with horses undergoing JC or JJ and that JC would be associated with a higher long-term mortality and occurrence of colic. Methods: Retrospective cross-sectional study. Meth...
Mansfield LS, Schott HC, Murphy AJ, Rossano MG, Tanhauser SM, Patterson JS, Nelson K, Ewart SL, Marteniuk JV, Bowman DD, Kaneene JB.Sarcocystis neurona is a protozoan parasite that can cause neurological deficits in infected horses. The route of transmission is by fecal-oral transfer of sporocysts from opossums. However, the species identity and the lifecycle are not completely known. In this study, Sarcocystis merozoites from eight isolates obtained from Michigan horses were compared to S. neurona from a California horse (UCD1), Sarcocystis from a grackle (Cornell), and five Sarcocystis isolates from feral opossums from Michigan. Comparisons were made using several techniques. SDS-PAGE analysis with silver staining showed...
Winter RL, Tian Y, Caldwell FJ, Seeto WJ, Koehler JW, Pascoe DA, Fan S, Gaillard P, Lipke EA, Wooldridge AA.Endothelial colony forming cells (ECFCs) may be useful therapeutically in conditions with poor blood supply, such as distal limb wounds in the horse. Encapsulation of ECFCs into injectable hydrogel microspheres may ensure cell survival and cell localization to improve neovascularization and healing. Autologous ECFCs were isolated from 6 horses, labeled with quantum nanodots (QD), and a subset were encapsulated in poly(ethylene) glycol fibrinogen microspheres (PEG-Fb MS). Full-thickness dermal wounds were created on each distal limb and injected with empty PEG-Fb MS, serum, ECFCs, or ECFCs enca...
Dierks C, Löhring K, Lampe V, Wittwer C, Drögemüller C, Distl O.A genome-wide scan was performed to detect quantitative trait loci (QTLs) for osteochondrosis (OC) and osteochondrosis dissecans (OCD) in horses. The marker set comprised 260 microsatellites. We collected data from 211 Hanoverian warmblood horses consisting of 14 paternal half-sib families. Traits used were OC (fetlock and/or hock joints affected), OCD (fetlock and/or hock joints affected), fetlock OC, fetlock OCD, hock OC, and hock OCD. The first genome scan included 172 microsatellite markers. In a second step 88 additional markers were chosen to refine putative QTLs found in the first scan....
Gibson KT, McIlwraith CW, Turner AS, Stashak TS, Aanes WA, Trotter GW.A retrospective study was made of 58 horses with open joint injuries admitted to the veterinary teaching hospital. Twenty-five (43%) were admitted within 24 hours of injury, 15 (26%) were examined 2 to 7 days after injury, and 18 (31%) were evaluated a week or more after the initial injury. The joints of the lower portions of the limbs most commonly were affected, with injuries that varied from puncture wounds to severe lacerations with soft tissue deficits. Diagnosis was made on the basis of clinical signs and results of synovial fluid analysis and radiography. Radiography was found to be an ...
Collins SN, Dyson SJ, Murray RC, Burden F, Trawford A.Anatomical change within a laminitic foot is of diagnostic and prognostic importance. A lateromedial radiograph represents the current 'gold standard' by which these changes are identified. Detection of anatomical change is dependent upon a priori knowledge of normality and subjective assessment alone may not identify modest change. Normal baseline data is, therefore, needed against which objective comparisons can be made. There is little information regarding the radiological anatomy of the donkey foot, hence an equine model has been widely adopted. However, descriptive accounts suggest funda...
Tzelos T, Geyer KK, Mitchell MC, McWilliam HEG, Kharchenko VO, Burgess STG, Matthews JB.Cyathostomins are ubiquitous parasitic nematodes of horses. These worms spend substantial periods as intestinal wall stage encysted larvae, which can comprise up to 90% of the total burden. Several million larvae have been reported in individuals. Emergence of these larvae from the gut wall can lead to life-threatening colitis. Faecal egg count tests, increasingly used by horse owners to inform anthelmintic treatments, do not correlate with the intra-host burden of cyathostomins; this represents a key gap in the diagnostic toolbox. Previously, a cyathostomin Gut Associated Larval Antigen was i...
Gargala G, Le Goff L, Ballet JJ, Favennec L, Stachulski AV, Rossignol JF.Sarcocystis neurona is an obligate intracellular parasite that causes equine protozoal myeloencephalitis (EPM). The aim of this work was to document inhibitory activities of nitazoxanide (NTZ, [2-acetolyloxy-N-(5-nitro 2-thiazolyl) benzamide]) and new thiazolides/thiadiazolides on S. neurona in vitro development, and investigate their structure-activity relationships. S. neurona was grown in bovine turbinate cell cultures. At concentrations varying from 1.0 to 5.0mg/L, nitazoxanide and 21 of 32 second generation thiazolide/thiadiazolide agents exerted a > or =95% maximum inhibition on S. neuro...
Pearson W, Fletcher RS, Kott LS.A biological extract of high-rosmarinic acid mint (HRAM) has previously demonstrated inhibitory effects on lipopolysaccharide (LPS)-induced prostaglandin E(2) (PGE(2)), nitric oxide (NO) and glycosaminoglycan (GAG) release in vitro. This study was undertaken to determine whether HRAM added to feed produces similar effects in horses challenged with intra-articular LPS. Eight horses received HRAM (0 or 28.1 ± 1.3 g/day; n = 4 per group) in their feed for 24 days in a blinded manner. On day 21, all horses received an intra-articular injection of LPS (0.3 ng) into their left or right intercarpal ...
Southwood LL, Schott HC, Henry CJ, Kennedy FA, Hines MT, Geor RJ, Hassel DM.Thirty-five cases of disseminated hemangiosarcoma (21 clinical cases and 14 previously reported cases) were reviewed to describe the disease in horses. Hemangiosarcoma occurred in mature, particularly middle-aged horses, with no apparent sex predilection. Thoroughbreds seemed to be overrepresented (13 cases) but a true breed predilection could not be established. The respiratory and musculoskeletal systems were most commonly affected and presenting complaints included dyspnea (26%), subcutaneous or muscular swelling (24%), epistaxis (17%), and lameness (12%). Heart and respiratory rates were u...
Stegelmeier BL, Colegate SM, Knoppel EL, Rood KA, Collett MG.Wild parsnip (Pastinaca sativa) has been associated with livestock and human photosensitization. An investigation of a natural occurrence of photosensitization of grazing horses identified wild parsnip as a possible cause. HPLC-MS and MS/MS analysis of this plant identified five furanocoumarins i.e., xanthotoxin, bergapten, isopimpinellin, imperatorin and a putative methoxyimperatorin. Goats fed this wild parsnip were largely unaffected. Xanthotoxin was not detected in the serum of parsnip-fed goats or in the serum of goats dosed orally or intravenous with purified xanthotoxin. Cutaneous appli...
Knych HK, Casbeer HC, McKemie DS, Arthur RM.Butorphanol is a narcotic analgesic commonly used in horses. Currently, any detectable concentration of butorphanol in biological samples collected from performance horses is considered a violation. The primary goal of the study reported here was to update the pharmacokinetics of butorphanol following intravenous administration, utilizing a highly sensitive liquid chromatography-mass spectrometry (LC-MS) assay that is currently employed in many drug-testing laboratories. An additional objective was to characterize behavioral and cardiac effects following administration of butorphanol. Ten exer...
Zipplies JK, Hauck SM, Eberhardt C, Hirmer S, Amann B, Stangassinger M, Ueffing M, Deeg CA.In equine recurrent uveitis (ERU), immune reactions are directed toward known antigens like S-antigen, interphotoreceptor retinoid-binding protein, and cellular retinalaldehyde-binding protein, and anti-retinal antibodies were detected in vitreous samples. The aim of this study was the investigation of intraocular immunoglobulin M (IgM) reactivities to retinal proteome. Methods: Retina was separated by one- and two-dimensional gel electrophoresis and blotted semidry on PVDF membranes. To identify intraocular IgM antibody responses to retinal tissue, blots were incubated with vitreous samples o...
Cuervo-Arango J, Claes AN, Ruijter-Villani M, Stout TA.Previous surveys reported a positive association between the length of the follicular phase and subsequent fertility in embryo transfer donor and Thoroughbred mares. However, it is unclear whether a longer oestrus positively influences fertilisation and oviductal development (oocyte quality, oviductal environment), or uterine receptivity and survival of the embryo in the uterus. Objective: To determine the effect of length of oestrus (characterised by duration of endometrial oedema) on likelihood of pregnancy and early embryo loss (EEL) in recipient mares after embryo transfer (ET). Methods: R...
Battut IB, Kempfer A, Lemasson N, Chevrier L, Camugli S.Spermatozoa from some stallions do not maintain an acceptable fertility after freezing and thawing. The selection of frozen ejaculates that would be suitable for insemination is mainly based on post-thaw motility, but the prediction of fertility remains limited. A recent study in our laboratory has enabled the determination of a new protocol for the evaluation of fresh stallion semen, combining microscopical observation, computer-assisted motility analysis and flow cytometry, and providing a high level of fertility prediction. The purpose of the present experiment was to perform similar invest...
Equine arteritis virus (EAV) is the causative agent of equine viral arteritis (EVA), a respiratory and reproductive disease of equids. There has been significant recent progress in understanding the molecular biology of EAV and the pathogenesis of its infection in horses. In particular, the use of contemporary genomic techniques, along with the development and reverse genetic manipulation of infectious cDNA clones of several strains of EAV, has generated significant novel information regarding the basic molecular biology of the virus. Therefore, the objective of this review is to summarize cur...
Hanson LJ, Eisenbeis HG, Givens SV.Lasalocid was given to horses in a series of sequentially increasing single oral doses ranging between 5 and 30 mg/kg of body weight, with an appropriate washout period between treatments. One of the 5 horses died after a dosage of 15 mg/kg, 1 of 3 horses died after 21 mg/kg, 1 of 3 horses died after 22 mg/kg, and 1 of 2 horses died after 26 mg/kg. The LD50 of lasalocid for horses was estimated to be 21.5 mg/kg. Monensin was given to horses in a similar manner at dosages of 1, 2, and 3 mg/kg of body weight. One of the 2 horses died after a dosage of 2 mg/kg and 1 horse died after a dosage of 3...
Golland LC, Evans DL, Stone GM, Tyler-McGowan CM, Hodgson DR, Rose RJ.The effects of training and over-training on plasma cortisol and beta-endorphin (betaEP) concentrations at rest and after standardised exercise tests and the cortisol responses to adrenocorticotropin (ACTH) administration were investigated in standardbred horses. Twelve horses were divided randomly into control and over-trained (OT) groups after 17 weeks slow- and moderate-intensity treadmill training. The standardised treadmill exercise test consisted of 2 min at velocities corresponding to 30, 50, 70 and 100% of maximum O2 consumption. Over-training, defined as a significant decrease in body...
Burns GA, Karcher LF, Cummings JF.A 4-year-old Standardbred mare was referred to the New York State College of Veterinary Medicine for colic evaluation. Physical examination revealed a small colon impaction which initially responded to conservative medical management. Her signs soon recurred, however, and an exploratory celiotomy was recommended. At surgery the small colon impaction was confirmed. The impaction was evacuated and a surgical biopsy was submitted for histopathologic evaluation. Microscopic examination of H&E and Trichrome sections revealed a massive mononuclear cell infiltration of the myenteric plexus. In additi...
Grundmann IN, Drost WT, Zekas LJ, Belknap JK, Garabed RB, Weisbrode SE, Parks AH, Knopp MV, Maierl J.Evaluation of laminitis cases relies on radiographic measurements of the equine foot. Reference values have not been established for all layers of the foot. Objective: To establish normal hoof wall and sole measurements using digital radiography (DR) and magnetic resonance imaging (MRI) and to document tissue components present in the dorsal hoof wall and solar layers seen on DR. Methods: Prospective observational case-control study. Methods: Digital radiography and MRI were performed on 50 cadaver front feet from 25 horses subjected to euthanasia for nonlameness-related reasons. Four observer...
Elhay M, Newbold A, Britton A, Turley P, Dowsett K, Walker J.To examine the immunogenicity of an equine immunocontraceptive vaccine and its efficacy in controlling hormone-related behaviour. Methods: A total of 24 mares at two sites in Australia were vaccinated with an immunocontraceptive vaccine comprising gonadotrophin releasing hormone (GnRH) conjugated to a carrier protein in immunostimulating complex as an adjuvant. Twelve animals at each site received a placebo of adjuvant alone and served as controls for seasonal oestrus, hormonal and behaviour patterns. Animals were observed for injection site reactions, ovarian and follicular activity, and seru...
Bannai H, Takahashi Y, Ohmura H, Ebisuda Y, Mukai K, Kambayashi Y, Nemoto M, Tsujimura K, Ohta M, Raidal S, Padalino B.This study evaluated the effects of 12-hour transportation on immune responses to equine herpesvirus type 1 (EHV-1) and type 4 (EHV-4). Possible replication of EHV-1 and EHV-4 was monitored by real-time PCR of nasal swabs and peripheral blood mononuclear cells (PBMCs), and changes in systemic and mucosal antibodies were investigated. Six healthy Thoroughbreds with transport experience were transported in commercial trucks, repeating the same three-hour route four times. Blood samples for cortisol measurement were taken before departure and every three hours. Nasal swabs, PBMCs, nasal wash and ...
Theelen MJP, Wilson WD, Byrne BA, Edman JM, Kass PH, Mughini-Gras L, Magdesian KG.Antimicrobial treatment protocols for foals with sepsis that do not improve clinically often are adjusted based on bacteriological and antimicrobial susceptibility testing results from samples collected at hospital admission. Objective: To evaluate whether hospitalization for ≥48 hours affects bacteriological and antimicrobial susceptibility testing results. Methods: Two-hundred sixty-seven foals <30 days of age admitted to a neonatal intensive care unit and diagnosed with sepsis. Methods: Medical records were reviewed retrospectively to identify foals with sepsis and positive bacteri...
Clark-Price SC.Recovery from anesthesia can be one of the most dangerous and unpredictable elements of providing anesthesia to horses. Strategies to quiet, control, and improve the quality of recovery of horses can be implemented in most situations and circumstances. This article provides an overview of the recovery period and areas where interventions may be practical to clinicians to provide improved care for their equine patients.
McIlwraith CW, Van Sickle DC.Arthritis was experimentally induced in the intercarpal joints of a series of mature ponies by the intraarticular injections of 400 microgram of the polyene antibiotic filipin in 1 ml of dimethyl sulfoxide. Twelve consecutive weekly injections were administered and the ponies were euthanatized 4 weeks after the last injection of filipin was made. The ponies were exercised for 1 hour each day throughout the experiment. Articular cartilage specimens from 4 sites in each intercarpal joint were examined histologically and histo-chemically. For the histochemical examination, safranin O-fast green, ...
