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.
Hamamoto-Hardman BD, Steffey EP, Seminoff K, McKemie DS, Kass P, Knych HK.Although morphine has demonstrated antinociceptive effects in horses, its administration has been associated with dose-dependent adverse effects. In humans and rats, part of the analgesic effect of morphine has been attributed to the active metabolite, morphine-6-glucuronide (M6G). Although morphine can cause several undesirable effects, M6G has a more favorable safety profile. The objective of this study was to characterize the pharmacokinetics, tissue distribution, and behavioral and select physiological effects of M6G following intravenous administration to a small group of horses. In Part ...
MacKay RJ, Howe DK.Advances in the understanding of equine protozoal myeloencephalitis (EPM) are reviewed. It is now apparent that EPM can be caused by either of 2 related protozoan parasites, Sarcocystis neurona and Neospora hughesi, although S neurona is the most common etiologic pathogen. Horses are commonly infected, but clinical disease occurs only infrequently; the factors influencing disease occurrence are not well understood. Epidemiologic studies have identified risk factors for the development of EPM, including the presence of opossums and prior stressful health-related events. Attempts to reproduce EP...
Ruby RE, Janes JG.The variety of neurologic diseases which affect horses makes pathologic examination of the nervous system a complex and lengthy process. An understanding of the common causes of neurologic disease, antemortem neurolocalization, and supplementation of the necropsy examination with ancillary testing will help to diagnose a large number of causes of neurologic disease. A general understanding of neuropathology and collaborative relationship with your local pathologists will aid in the definitive diagnosis of neurologic diseases.
Johnson SA.Rehabilitation of the neurologic horse represents a unique challenge for the equine practitioner. Improving postural stability and balance control through improving the strength of the spinal stabilizer muscle multifidus remains one of the most promising rehabilitative targets. This muscle can be targeted through the use of physiotherapeutic exercises, various forms of perturbation, and even whole-body vibration. Neuroanatomic localization and diagnosis specificity enable the practitioner to determine suitability for such rehabilitative tasks, and with the advent of evolving strategies and com...
Journée HL, Journée SL.Depending on the localization of the lesion, spinal cord ataxia is the most common type of ataxia in horses. Most prevalent diagnoses include cervical vertebral stenotic myelopathy (CVSM), equine protozoal myeloencephalitis (EPM), trauma and equine degenerative myeloencephalopathy (EDM). Other causes of ataxia and weakness are associated with infectious causes, trauma and neoplasia. A neurologic examination is indispensable to identify the type of ataxia. In addition, clinical neurophysiology offers tools to locate functional abnormalities in the central and peripheral nervous system. Clinical...
Nout-Lomas YS.Mechanisms of traumatic nervous system injury to a degree are similar, but differences exist in etiology, pathophysiology, and treatment of brain, spinal cord, and peripheral nerve injury. The most common clinical abnormalities seen in the horse are abnormal level of consciousness, abnormal behavior, seizures, cranial nerve deficits, vestibular disease, tetra- and paraparesis or paraplegia, cauda equina syndrome, specific gait deficits, and muscle atrophy. Treatments are directed toward reducing inflammation and swelling, halting secondary injury, and promoting mechanisms of neuroregeneration ...
Valberg SJ.Movement disorders are defined as involuntary movements that are not due to a painful stimulus or associated with changes in consciousness or proprioception. Diagnosis involves ruling out any lameness and neurologic disease and characterizing the gait during walking backward and forward and trotting. Shivers causes abnormal hindlimb hypertonicity during walking backward and, when advanced, a few strides walking forward. Stringhalt causes consistent hyperflexion during walking forward and trotting and variable difficulty when walking backward. Classification and potential causes are discussed a...
Hurni JI, Kaiser-Thom S, Gerber V, Keller JE, Collaud A, Fernandez J, Schwendener S, Perreten V.A total of 100 nasal swabs were collected from healthy horses in Switzerland between January 2020 and August 2020. The samples were taken from horses at 40 different stables in 12 different cantons and screened for both methicillin-resistant (MRSA) and methicillin-susceptible S. aureus (MSSA) using selective agar plates. S. aureus were tested for antibiotic susceptibility by measurement of the minimal inhibitory concentration (MIC) and for virulence factors, antibiotic resistance genes and phylogenetic characteristics using whole genome sequence analysis. Ten horses were found to be positiv...
Finno CJ, Johnson AL.Neuroaxonal degenerative disease in the horse is termed equine neuroaxonal dystrophy (eNAD), when pathologic lesions are localized to the brainstem and equine degenerative myeloencephalopathy (EDM) and degenerative changes extend throughout the spinal cord. Both pathologic conditions result in identical clinical disease, most commonly characterized by the insidious onset of ataxia during early development. However, later onset of clinical signs and additional clinical features, such as behavior changes, is also observed. A definitive diagnosis of eNAD/EDM requires histologic evaluation of the ...
Furr MO.Neurologic disease of foals is a diagnostic and therapeutic challenge for veterinarians. Disease conditions such as neonatal encephalopathy are seen as well as developmental and congenital defects, bacterial infections, and trauma. Neonatal encephalopathy can be considered a "syndrome" with a variety of causes resulting in a similar clinical presentation. These causes can be categorized as maladaptation, hypoxic/ischemic encephalopathy, and metabolic abnormalities, all leading to signs of cerebral and brainstem disease. Spinal cord signs may occasionally be seen, but these signs are usually ov...
Aleman M.The vestibular system (VS) is the primary specialized sensory system responsible for maintaining balance (equilibrium) and orientation of the eyes, neck, trunk, and limbs during rest and movement. Two important reflexes are responsible for maintaining balance: vestibulo-ocular and vestibulospinal reflexes. These reflexes involve peripheral and central components of the VS. Whether central or peripheral disease, most of the disorders of the VS result in ipsilateral neurologic deficits. A few uncommon exceptions present with contralateral signs to the site of the lesion. This article provides a ...
van Spijk JN, Beckmann K, Wehrli Eser M, Boxler M, Stirn M, Rhyner T, Kaelin D, Saleh L, Schoster A.Polymyxin B (PolyB) is used to treat endotoxemia in horses; neurologic and nephrogenic adverse effects occur in humans. Objective: To describe PolyB adverse effects in horses. Methods: Five healthy horses (ataxia 0/5), 1 horse with cervical osteoarthritis (ataxia 1/5). Methods: Prospective blinded randomized cross-over trial; 3-weeks wash out. Horses received PolyB (PolyB 6000 IU/kg IV, 7 doses q12h, n = 6) and PolyB/gentamicin (PolyB 6000 IU/kg IV, q12h 7 doses; gentamicin 10 mg/kg IV q24h 4 doses n = 4, or q12-24 h 5 doses because of an additional erroneous dose, n = 2). Daily n...
Fitzharris LE, Hezzell MJ, McConnell AK, Allen KJ.Little is known about the response of the equine respiratory muscles to training. Objective: To measure an index of inspiratory muscle strength (IMSi) before and after a period of conventional exercise training (phase 1) and inspiratory muscle training (IMT), comparing high-load (treatment) and low-load (control) groups (phase 2). Methods: Prospective randomised controlled trial. Methods: Phase 1: Twenty National Hunt Thoroughbred racehorses performed an inspiratory muscle strength test (IMST) twice on two occasions; when unfit at timepoint A (July), and when race fit at timepoint B (October)....
Garrett KS.Diagnostic imaging is often an important part of the diagnostic approach to neurologic disease. Advanced imaging techniques such as myelography, computed tomography (CT), and magnetic resonance imaging (MRI) provide more information than radiography and ultrasonography but are more limited in their availability. The clinician should be cognizant of the findings of the clinical examination when interpreting diagnostic imaging findings.
MacKay RJ, Howe DK.Advances in the understanding of equine protozoal myeloencephalitis (EPM) are reviewed. It is now apparent that EPM can be caused by either of 2 related protozoan parasites, Sarcocystis neurona and Neospora hughesi, although S neurona is the most common etiologic pathogen. Horses are commonly infected, but clinical disease occurs only infrequently; the factors influencing disease occurrence are not well understood. Epidemiologic studies have identified risk factors for the development of EPM, including the presence of opossums and prior stressful health-related events. Attempts to reproduce EP...
Toribio RE.Several viruses transmitted by biological vectors or through direct contact, air, or ingestion cause neurologic disease in equids. Of interest are viruses of the Togaviridae, Flaviviridae, Rhabdoviridae, Herpesviridae, Bornaviridae, and Bunyaviridae families. Variable degree of inflammation is present with these viruses but lack of an inflammatory response does not rule out their presence. The goal of this article is to provide an overview on pathophysiologic and clinical aspects of nonarboviral equine encephalitides, specifically on lyssaviruses (rabies) and bornaviruses (Borna disease).
Raspa F, Tarantola M, Muca E, Bergero D, Soglia D, Cavallini D, Vervuert I, Bordin C, De Palo P, Valle E.Horses reared for meat production are generally fed a diet rich in starch with the aim of maximizing production performances. This study evaluated the effects of two feeding management systems on horse welfare by analysing the relative time spent engaged in different behavioural activities. Nineteen Bardigiano horses aged 14.3 ± 0.7 months were randomly assigned to one of two group pens: one group was fed high amounts of starch-rich concentrates (HCG; = 10), the other was fed a fibre-based diet (HFG; = 9). Behavioural activities performed by each horse were video-recorded over a 96-h period...
Ing S.A 22-year-old miniature horse gelding was brought to a veterinary clinic with multiple porcupine quills embedded in the face. One quill had perforated through the left caudoventral cornea but did not extend beyond the anterior chamber. The horse was referred to a specialist clinic for removal of the intraocular quill and subsequent primary surgical repair of the corneal wound. Following aggressive medical treatment, the horse retained vision. Piquants de porc-épic oculaires et faciaux chez un cheval miniature. Un cheval hongre miniature de 22 ans a été amené à une clinique vétérinaire a...
Wang Y, Li X, Chen X, Kulyar MF, Duan K, Li H, Bhutta ZA, Wu Y, Li K.It is critical to characterize changes in the structure and composition of the host fungal community in natural infection, because it gives the possible overview of gut microbiome in host homeostasis and disease progression. A total of 168 rectal fecal samples were collected and examined using nPCR. The positive samples were double-checked using 18S rDNA high-throughput sequencing. After confirmation, ITS high-throughput sequencing was utilized to investigate the fungal community's response to natural infection. Results showed that a total of three positive samples (1.79%) were identified wi...
Ricard RM, St-Jean G, Duizer G, Atwal H, Wobeser BK.The purpose of this study was to identify the most common causes of equine abortion in Canada, and to compare findings to similar reports from other countries. Equine. Necropsy reports from 901 equine abortion cases were acquired from provincial veterinary diagnostic laboratories across Canada. The final diagnosis was classified into basic abortion causes (infectious, non-infectious, unknown) and into primary and secondary categories for analysis. Non-infectious causes of abortion were the most frequently identified in Canada, with fetoplacental causes, including umbilical cord torsion or plac...
Supokawej A, Korchunjit W, Wongtawan T.The Wingless and Int-1 (WNT) and bone morphogenic protein/growth differentiation factor (BMP/GDF) signalling pathways contribute significantly to the development of the musculoskeletal system. The mechanism by which they contribute is as follows: BMP/GDF signalling usually promotes tendon differentiation, whereas WNT signalling inhibits it. We hypothesised that inhibiting WNT and subsequently stimulating BMP signalling may enhance the tenogenic differentiation of stem cells. The objective of this study was to determine whether a combination of WNT inhibitor (KY02111) and BMP12/GDF7 protein cou...
Emmerich IU.In 2021, one novel pharmaceutical agent for horses or food-producing animals was released on the German market, making the anti-haemorrhagic etamsylate (Hemosilate) available for horses, cattle, pigs, sheep, goats, dogs and cats, for the first time. The authorization of one established veterinary active ingredient was extended to an additional species: The endectocide eprinomectin (Eprecis) from the group of macrocyclic lactones was also approved for sheeps and goats. Additionally, two veterinary formulations with a new active substance content (bromhexine, tiamulin) and one active ingredient ...
Zhang K, Zhou R, Huang H, Ma W, Qi Y, Li B, Zhang D, Li K, Chu H.The aim of this study was to identify the aggregation sites and transmission characteristics of Gasterophilus pecorum, the dominant pathogen of endangered equines in desert steppe. Therefore, we tested with a four-arm olfactometer the olfactory response of the G. pecorum adults to the odors that have a great impact on their life cycle, and also investigated the occurrence sites of the adults in the area where the Przewalski's horse (Equus przewalskii) roam frequently during the peak period of G. pecorum infection. The results of four-directional olfactory test showed that the fresh horse feces...
Durham AE, Potier JF, Huber L.Use of plasma adrenocorticotropic hormone (ACTH) concentrations for the diagnosis of PPID in equids requires awareness of other factors that might influence ACTH concentrations, including breed and time of year. This study was designed to investigate effects of breed on plasma ACTH concentrations and potential interactions between breed and time of year. Ten breeds were selected from a laboratory database containing data on plasma ACTH concentrations. Breeds represented were Arabians, Cobs, Connemara ponies, donkeys, Irish Sports horses, New Forest ponies, Shetland ponies, Thoroughbreds, Warmb...
Han L, Lan T, Lu Y, Zhou M, Li H, Lu H, Wang Q, Li X, Du S, Guan C, Zhang Y, Sahu SK, Qian P, Zhang S, Zhou H, Guo W, Chai H, Wang S, Liu Q, Liu H....The evolution of parasites is often directly affected by the host's environment. Studies on the evolution of the same parasites in different hosts are of great interest and are highly relevant to our understanding of divergence. Methods: Here we performed whole-genome sequencing of Parascaris univalens from different Equus hosts (horses, zebras and donkeys). Phylogenetic and selection analyses were performed to study the divergence and adaptability of P. univalens. Results: At the genetic level, multiple lines of evidence indicate that P. univalens is mainly separated into two clades (horse-de...
Reich P, Falker-Gieske C, Pook T, Tetens J.Genotype imputation is a cost-effective method to generate sequence-level genotypes for a large number of animals. Its application can improve the power of genomic studies, provided that the accuracy of imputation is sufficiently high. The purpose of this study was to develop an optimal strategy for genotype imputation from genotyping array data to sequence level in German warmblood horses, and to investigate the effect of different factors on the accuracy of imputation. Publicly available whole-genome sequence data from 317 horses of 46 breeds was used to conduct the analyses. Results: Depend...
Wattanapornpilom T, Pornprasitroj P, Thongsri K, Iamprapai S, Suan-Aoy P, Chanda M.Chronic laminitis is a late stage of laminitis in horses characterised by distal phalangeal rotation and foot pain. Various trimming and shoeing methods have been implemented; however, they sometimes aggravate lameness, particularly in laminitic horses with poor hoof quality. Sand bedding confinement has alternatively been employed to relieve foot pain in laminitic horses; however, the impact of long-term confined sand bed accommodation on hoof conditions is unknown. Moreover, the time course of sand bedding housing for managing chronic laminitis has yet to be described. We report the outcome ...
Lossi L.The anatomical characteristics of each of the many species today employed in biomedical research are very important when selecting the correct animal model(s), especially for conducting translational research. In previous papers, these features have been considered for fish (D'Angelo et al., 2016), the most common laboratory rodents, rabbits, and pigs (Lossi et al. 2016). I here follow this line of discussion by dealing with the importance of proper knowledge of ferrets, goats, sheep, and horses' main anatomical features in translational research.
Ramos S, Pinto A, Crespo J, Marques JP, Bettencourt E, Gama LT, Monteiro S.Osteochondrosis (osteochondritis dissecans), OC(D), is an important joint disorder that has been studied through the years in different breeds but, to our knowledge, there are no reports of its prevalence in Lusitano horses. The aim of this study was to assess the prevalence of OC(D) in Lusitanos, define the characteristics of the disorder in this breed and compare with Spanish Purebred horses. This is a retrospective study that analysed the radiographs from the metacarpometatarsophalangeal, tarsocrural and femoropatellar joints that were taken in 302 Lusitano horses (1-12 years; obtained from...
Kernot N, Butler R, Randle H.Conditions of the equine caudal neck (C5-C7) are thought to be associated with various clinical signs. However, little investigation has been undertaken to isolate clinical indicators associated with specific conditions of the equine caudal cervical spine. This systematic review aimed to evaluate associations of clinical signs with anatomical malformation of caudal cervical vertebrae, spinal cord compression of the caudal cervical spine, and arthropathy of the caudal cervical articular process joints (APJs). A literature search was carried out using Google Scholar in accordance with PRISMA (Pr...
Shah SZA, Nawaz Z, Nawaz S, Carder G, Ali M, Soomro N, Compston PC.Equine ownership is a common income-generating strategy in Pakistan. In Karachi, donkey carts are used to transport building materials, commercial produce and garbage. This study aimed to articulate the role and welfare of donkeys used in waste management. We conducted interviews with donkey owners ( = 200), households which use donkey carts for waste collection ( = 50) and key informants ( = 14). To assess the welfare of donkeys, the Standardised Equine-Based Welfare Assessment Tool (SEBWAT) was used ( = 204). Collection of waste was the primary source of income for 89% of owners interviewed....
Mooij MJ, Jans W, den Heijer GJ, de Pater M, Back W.There is a lack of evidence for the presumed beneficial effects of water treadmills on the movement of the horse's back. The aim of the study was to evaluate the effects of water treadmill exercise on axial rotation (AR), lateral bending (LB) and pelvic flexion (PF) in horses. The back kinematics of a group of riding horses were studied at the walk in a water treadmill at different depths of water (hoof, fetlock, carpus, elbow and shoulder joint levels) over a period of 10 days. Skin markers were placed at anatomical locations on the back. AR, LB and PF were measured on days 1 and 10 using two...
McGowan TW, Pinchbeck G, Phillips CJ, Perkins N, Hodgson DR, McGowan CM.To describe the prevalence and risk factors for clinical signs of disease and owner-reported health or welfare issues of aged horses in Queensland, Australia. Methods: Owners of horses were contacted via an equestrian organisation in Queensland and asked to complete a questionnaire about their horses aged 15 years and older, to gain information about clinical signs observed in the horse and disease history. Owners were asked to identify health or welfare issues they felt were important in aged horses. Results: Owners were able to identify many clinical signs of disease, with 83% of horses havi...
Simbizi V, Saulez MN, Potts A, Lötter C, Gummow B.Most leptospiral infections in horses are asymptomatic; however, acute disease manifestations as well as reproductive failure and recurrent uveitis have been reported. In South Africa, the epidemiology of the disease in horses is not well documented. A serosurvey to determine what serovars were present in horses from Gauteng, KwaZulu-Natal and Western Cape Provinces and to get an estimate of the seroprevalence of leptospirosis was carried out from January 2013 until April 2014 with the assistance of four large equine hospitals located in these provinces. Furthermore, associations between poten...
Liu A, Zhang J, Zhao J, Zhao W, Wang R, Zhang L.Horses interact with humans in a wide variety of sport competitions and non-competitive recreational pursuits as well as in working activities. Cryptosporidium spp are one of the most important zoonotic pathogens causing diarrhea of humans and animals. The reports of Cryptosporidium in horses and the findings of zoonotic Cryptosporidium species/genotypes show a necessity to carry out molecular identification of Cryptosporidium in horses, especially in diarrheic ones. The aim of the present study was to understand Cryptosporidium infection and species/genotypes in diarrheic horses, and to trace...
Faubladier C, Sadet-Bourgeteau S, Philippeau C, Jacotot E, Julliand V.This study assessed the time-scale variability of bacterial community structure in foal feces from birth to 365 days of age using Automated Ribosomal Intergenic Spacer Analysis (ARISA). Fecal samples were collected from five foals 2 h after birth (meconium) and in the morning at days 1, 2, 5, 10, 30, 60, 120, 179, 183, 194 and 365. The ARISA profiles were compared using an analysis of similarity (ANOSIM). Although both the age effect and the foal effect were highly significant (P < 0.010), the R-ANOSIM value for the foal effect was very low (R-ANOSIM = 0.089), while that of the age eff...
Lange CE, Vetsch E, Ackermann M, Favrot C, Tobler K.Papillomaviruses appear to be species-specific pathogens, and it was suggested that each animal species might harbour its own set of papillomaviruses. However, all approaches addressing the underlying evolutionary phenomena still suffer from very limited data about animal papillomaviruses. In case of the horse for example, only three equine papillomaviruses (EcPVs) have been identified. To further address the situation in this host, suspected papillomavirus-associated lesions were tested for EcPV DNA. Four novel EcPV types were detected and their genomes entirely cloned and sequenced. They dis...
Zoonoses and public healthFebruary 1, 2008
Volume 55, Issue 2 106-111 doi: 10.1111/j.1863-2378.2007.01095.x
Gür S, Yapkiç O, Yilmaz A.The bovine enterovirus type 1 (BEV-1) infection has a wide range of host spectrum including humans. In this study, seroprevalence of BEV-1 was investigated in eight mammalian species. Blood serum samples were collected from 244 humans, 1520 cattle, 272 horse, 126 dog, 281 sheep, 477 goat, 18 camel (Camelus dromedarius) and 82 gazelle (Gazella subgutturosa subgutturosa) in different regions of Turkey. Microneutralization tests showed that gazelle and camel did not have any seropositivities, but seropositivities were detected in humans (30.3%), cattle (64.8%), horse (12.8%), dog (3.2%), sheep (3...
Dixon PM, Head KW.The clinical and pathological findings of 28 cases (27 horses, 1 donkey) of equid sinonasal tumours examined at the Edinburgh Veterinary School are presented and include: seven cases of squamous cell carcinoma (SCC); five adenocarcinomas; three undifferentiated carcinomas; two adenomas; five fibro-osseous and bone tumours; and single cases of ameloblastoma, fibroma, fibrosarcoma, undifferentiated sarcoma, melanoma and lymphosarcoma. The median ages of animals affected with epithelial, and fibro-osseous/bone tumours were 14 and 4 years, respectively. Unilateral purulent or mucopurulent nasal di...
Varela E, Rey J, Plaza E, Muñoz de Propios P, Ortiz-Rodríguez JM, Álvarez M, Anel-López L, Anel L, De Paz P, Gil MC, Morrell JM....Contaminating bacteria present in stallion ejaculates may compromise sperm quality during storage. Different procedures have been used to reduce the load of microorganisms in semen and avoid bacterial growth during storage. The aims of this study were: 1) to evaluate different techniques to eliminate bacteria in semen 2) to study the relationship between total microflora load (TML) and ROS production; and 3) to determine if TML affects the functionality of cool-stored sperm. Ejaculates from 11 stallions were split and processed in 3 ways: A. extended semen; B. conventional centrifuged semen, a...
Brindley MA, Maury W.Entry of wild-type lentivirus equine infectious anemia virus (EIAV) into cells requires a low-pH step. This low-pH constraint implicates endocytosis in EIAV entry. To identify the endocytic pathway involved in EIAV entry, we examined the entry requirements for EIAV into two different cells: equine dermal (ED) cells and primary equine endothelial cells. We investigated the entry mechanism of several strains of EIAV and found that both macrophage-tropic and tissue culture-adapted strains utilize clathrin-coated pits for entry. In contrast, a superinfecting strain of EIAV, EIAV(vMA-1c), utilizes ...
Browning GF, Studdert MJ.The epidemiology of equine herpesvirus 2 was examined by using restriction endonuclease DNA fingerprints to distinguish viruses isolated from two groups of horses. The first group consisted of three yearlings isolated from other horses but in contact with each other for 418 days, whereas the second comprised seven mares and their foals, which were sampled at monthly intervals from parturition until the foals were about 180 days old. There was a complex pattern of transmission, with 15 different viruses isolated from both groups. Four distinguishable viruses were isolated from the three yearlin...
Gorissen BM, Wolschrijn CF, van Vilsteren AA, van Rietbergen B, van Weeren PR.Bone is a dynamic tissue adapting to loading according to "Wolff's law of bone adaptation." During very early life, however, such a mechanism may not be adequate enough to adapt to the dramatic change in environmental challenges in precocial species. Their neonates are required to stand and walk within hours after birth, in contrast to altricial animals that have much more time to adapt from the intrauterine environment to the outside world. In this study, trabecular bone parameters of the talus and sagittal ridge of the tibia from stillborn but full-term precocials (calves and foals) were ana...
Ostlund EN.Two viruses, EHV-1 and EHV-4, are now known to be responsible for disease conditions formerly considered caused by "equine rhinopneumonitis virus." Although these viruses share several laboratory and clinical features, they differ in epidemiology and pathogenic potential. EHV-4 is primarily associated with clinical respiratory disease, whereas EHV-1 is more frequently isolated from aborted fetuses, sickly foals, and neurologic cases. Both viruses frequently establish latent infections, but the relevance of latency to clinical disease is unclear. Diagnosis based on identification of the pathoge...
Moore BR, Krakowka S, Robertson JT, Cummins JM.Cytologic examination of bronchoalveolar lavage fluid (BALF), including phenotypic analysis of lymphocytes, was performed on 32 Standardbreds with poor race performance and endoscopic examination findings characteristic of inflammatory airway disease (IAD). Nucleated cell counts in BALF from IAD-affected horses were higher than those in control horses; the cytologic profile of BALF in affected horses included mixed inflammation, characterized by mild neutrophilia, lymphocytosis, and monocytosis. Eosinophil and mast cell counts were not higher in the IAD-affected group, compared with those in t...
Maddox TW, Williams NJ, Clegg PD, O'Donnell AJ, Dawson S, Pinchbeck GL.The increasing prevalence of antimicrobial resistance in bacteria represents a considerable problem for human and veterinary medicine, causing complications in the treatment of infections. Resistance in Escherichia coli from horses has been documented in commensal and pathogenic strains, but little information exists regarding the prevalence of such bacteria in hospitalised horses or associated risk factors. A longitudinal cohort study was conducted of 103 horses admitted to a referral equine hospital for more than 48 h, with faecal samples collected on hospital admission and subsequently ever...
Ringer SK, Portier KG, Fourel I, Bettschart-Wolfensberger R.To elaborate constant rate infusion (CRI) protocols for xylazine (X) and xylazine/butorphanol (XB) which will result in constant sedation and steady xylazine plasma concentrations. Methods: Blinded randomized experimental study. Methods: Ten adult research horses. Methods: Part I: After normal height of head above ground (HHAG = 100%) was determined, a loading dose of xylazine (1 mg kg(-1) ) with butorphanol (XB: 18 μg kg(-1) ) or saline (X: equal volume) was given slowly intravenously (IV). Immediately afterwards, a CRI of butorphanol (XB: 25 μg kg(-1) hour(-1)) or saline (X) was administer...
Decloedt A, Van Steenkiste G, Vera L, Buhl R, van Loon G.Atrial fibrillation (AF) is the most common clinically relevant arrhythmia in horses, with a reported prevalence up to 2.5%. The pathophysiology has mainly been investigated in experimental animal models and human medicine, with limited studies in horses. Atrial fibrillation results from the interplay between electrical triggers and a susceptible substrate. Triggers consist of atrial premature depolarizations due to altered automaticity or triggered activity, or local (micro)reentry. The arrhythmia is promoted by atrial myocardial ion channel alterations, Ca2+ handling alterations, structural ...
Moore CP, Collins BK, Fales WH.Seventy-three aerobic bacterial isolates were cultured from 64 eyes of 63 horses with infectious keratitis. Forty-two (58%) of the organisms isolated initially were gram-positive (g+, 10 genera) and 31 (42%) were gram-negative (g-, 5 genera). After local antimicrobial treatment, repeat cultures from samples obtained from 15 eyes of hospitalized horses yielded 21 secondary bacterial isolates. Staphylococci spp and Streptococci spp were the most common g(+) isolates and accounted for 79% of g(+) organisms isolated initially. Antibiograms revealed ticarcillin to be the most efficacious antibiotic...
Kasashima Y, Smith RK, Birch HL, Takahashi T, Kusano K, Goodship AE.Most skeletal tissues are thought to adapt to the mechanical environment they experience. While this has been demonstrated for muscle and bone, previous studies in the mature horse have failed to demonstrate adaptation in the superficial digital flexor tendon (SDFT), which suffers a high frequency of injury. This study tested the hypothesis that imposed exercise during growth would result in an increase in SDFT cross-sectional area (CSA). Fourteen Thoroughbred foals were divided into 2 sex-matched groups. A control group received 4 h pasture exercise and an exercise group had the same amount o...
Rotter Sopasakis V, Wickelgren R, Sukonina V, Brantsing C, Svala E, Hansson E, Enerbäck S, Lindahl A, Skiöldebrand E.Chondrocytes are responsible for remodeling and maintaining the structural and functional integrity of the cartilage extracellular matrix. Because of the absence of a vascular supply, chondrocytes survive in a relatively hypoxic environment and thus have limited regenerative capacity during conditions of cellular stress associated with inflammation and matrix degradation, such as osteoarthritis (OA). Glucose is essential to sustain chondrocyte metabolism and is a precursor for key matrix components. In this study, we investigated the importance of glucose as a fuel source for matrix repair dur...
McLean AK, Navas González FJ, Canisso IF.Donkeys and mules often are misunderstood because of their behavioral differences compared with horses. Working with these animals requires more patience and ability to notice the slightest changes in behavior to diagnose disease. Mules and donkeys form strong bonds and trust with familiar people and other equids. Training mules and hinnies from an early age is key to modifying behavior and acceptance of unfamiliar people. Reproductive behavior is different from that of horses and requires more patience when collecting jacks. Practitioners working with mules and donkeys should take a methodolo...
Marsh RJ, Fraunfelder FT, McGill JI.The clinical differentiation of corneal epithelial lesions due to herpes simplex or herpes zoster may be confusing. Practical clinical tests, including the use of topical ocular stains, are useful to differentiate corneal epithelial lesions caused by these two viruses. Two distinctive types of zoster corneal epithelial disease may be seen; an early dendritic form, and a delayed form characterized by corneal mucus plaques that may take a dendriform pattern. These plaques are composed of mucus that is adherent to swollen, degenerating epithelial cells. The clinical differentiation between these ...
Wang AL, Kern T.Melanocytic neoplasms in veterinary species occur in various ophthalmic locations including the eyelid, conjunctiva, cornea, sclera, anterior and posterior uvea, and orbit. Histology usually provides the definitive diagnosis for melanocytic ocular neoplasias. The degree of tissue invasiveness and anaplastic cellular characteristics are more reliable indicators of biological behavior than is mitotic index in most ophthalmic melanocytic tumors. Melanocytic neoplasias of the eyelid are predominantly benign in canines and equines, though in felines, there is the potential for metastasis, especiall...
Kareskoski M, Katila T.Seminal plasma is a mixture of secretions produced in the testes, epididymides and accessory sex glands, and ejaculated as several consecutive fluid fractions. The composition of seminal plasma and the effects on sperm longevity vary between fractions and individual stallions. This review focuses on the sequence of ejaculation, constituents of seminal plasma and their potential use as fertility markers as well as the influence of seminal plasma on spermatozoa during storage.
Mitchell A, Rivas KA, Smith R, Watts AE.Equine superficial digital flexor tendon injury is a well-accepted model of human tendon injury and is routinely treated with local injections of autologous mesenchymal stem cells (MSCs). Identification of a clinically safe medium for short-term cryopreservation of MSCs prior to cell implantation would streamline laboratory and clinical procedures for autologous regenerative therapies. Veterinary experience with short-term (MSCs prepared after the injury has occurred) cryopreserved MSCs in naturally occurring injury in the horse will be of value to human practitioners. Methods: Equine bone mar...