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.
Bedogni G, Michelena LV, Seremeta K, Okulik N, Salomon C.Fenbendazole is an antiparasitic drug widely used in veterinary medicine to treat parasitic infections caused in animals like cattle, horses, sheep, and dogs. Recently, it has been repositioned as a potential alternative for cancer treatment. However, it is a highly hydrophobic molecule (0.9 ug/mL), which can compromise its dissolution rate and absorption. Thus, this work aimed to apply a nanotechnological approach to improve drug solubility and dissolution performance. Fenbendazole nanoparticles stabilized by different poloxamers were obtained by lyophilization without cryoprotectants. The be...
Giusto G, Gandini M.The return to performance after colic surgery is crucial for competition horses. While studies have investigated racehorse performance following colic surgery by analysing racing participation and earnings, this approach does not apply to showjumping horses, leaving a gap in the literature regarding their objective performance evaluation. Objective: To assess the short- and long-term survival and return to performance in showjumping horses after colic surgery. Methods: Retrospective case series. Methods: Medical records of horses with acute colic requiring surgical treatment were analysed, and...
Peretti JC, Dos Santos AB, Davi Dos Santos E, Machado TP, Pescador CA, Quillas LJA, Milani VM, Picetti TS, da Motta AC.Lymphoma is the most common tumor of hematopoietic origin in horses. The course of the disease and clinical signs vary greatly, depending on tumor location and extent. The aim of this report is to describe the occurrence of T-cell-rich oral large B-cell lymphoma with marked local infiltration in a 25-year-old Crioula mare. The mare showed an increase in volume on the right side of its face, dyspnea, anorexia, and progressive weight loss. The clinical assessment showed that the lesion was located in the rostral and caudal sinuses and was markedly invasive to adjacent structures. The autopsy rev...
Sibthorpe PEM, Fitzgerald DM, Sillence MN, de Laat MA.Equine insulin dysregulation (ID) is a significant metabolic problem because the hyperinsulinaemia that develops increases the animal's risk of developing laminitis, a debilitating foot condition. The role of gastrointestinal factors, such as incretin hormones, in the pathogenesis of ID and hyperinsulinaemia in horses is poorly understood, particularly in comparison to other species. Glucagon-like peptide-2 (GLP-2) is an intestinotrophic peptide released from L cells in the gastrointestinal tract and is implicated in metabolic dysfunction in other species. The aim of this study in vitro was to...
Preston JF, Mustikka MP, Priestnall SL, Dunkel B, Fischer MC.There is limited literature regarding equine immune mediated keratitis (IMMK) in Europe. North America-based publications describe minimal blepharospasm, rare corneal ulceration and no uveitis; clinical impression suggests these are seen in Europe. Objective: Assess the prevalence of blepharospasm, corneal ulceration and uveitis and their impact on outcome in horses diagnosed with IMMK in Europe (UK and Finland). Methods: Retrospective case series. Methods: Clinical records of 94 horses with IMMK were evaluated. The UK and Finland populations were comparable; therefore, descriptive statistics ...
Albrecht M, MacGillivray KC, Juez B, Freeland R.A 4.5-month-old Standardbred colt presented for neck swelling and fever. Endoscopy and contrast radiography identified a full thickness esophageal perforation. Surgical intervention with fasciotomies and placement of an esophageal feeding tube was elected. Intensive postoperative treatment was carried out with broad-spectrum antibiotics, gastroprotectants and probiotics, calculated feeding plan, esophagostomy and fasciotomy site lavages, care, and cleaning. Complications included recurrent bilateral pneumothorax and development of an incomplete fistula at the esophagostomy site following remov...
Hollis AR.Despite the ubiquitous nature of sarcoids, robust data regarding the selection of treatment modalities are scarce, with many treatments having little or no published data to support their use. Treatment options are numerous and vary with the location and type of sarcoid, treatment accessibility, and the financial status of the owner. Many treatments are expensive and time-consuming, and some have health and safety implications. It is this author's belief that, based on the limited evidence base, appropriate treatment options vary with the location and type of the sarcoid, and no one treatment ...
Anandu S, Tanuj GN, Vijayasarathi MK, Manjusha KM, Samanta S, Bandyopadhyay S, Sankar M.Ocular setariasis is an ectopic infection caused by a parasite under the genus Setaria. Adult worms belong to the Setariidae family and typically reside in the peritoneal cavity of ungulates. However, immature forms of these species may aberrantly migrate to the eyes of cattle, buffalo, goats, horses and several other hosts, leading to corneal opacity and blindness. Here, we have distinguished the Setaria digitata collected from both equine and buffalo hosts based on the morphology, molecular profiling of mitochondrial cytochrome c oxidase subunit 1 (Cox1), cytochrome c oxidase subunit 3 (Cox3...
Amari M, Rabbogliatti V, Ravasio G, Auletta L, Brioschi FA, Riccaboni P, Dell'Aere S, Roccabianca P.Radiofrequency (RF) relieves chronic pain in humans, but it is unexplored in horses affected by chronic lameness. This study aims to describe the technique and the histological effects of ultrasound (US)-guided radiofrequency ablation (RFA) of palmar digital nerves (PDNs) in horse's fetlock and pastern, . Unassigned: After assessing the US anatomy of lateral and medial PDNs in fetlock and pastern ( = 10 horses; 20 forelimbs), US-guided RFA was performed on these sites in cadaveric forelimbs ( = 10) applying four different settings with increasing invasiveness ( = 40 total treatmen...
Bekele D, Dessalegn B, Tadesse B, Abey SL.Strangles, caused by Streptococcus equi subspecies equi, is a highly infectious disease of equines causing major health issues and financial losses. The aim of the study was to detect the presence of the SeM gene in Streptococcus equi isolated from equine suspected of having strangles. A cross-sectional study design was conducted from July to December 2022 in five districts of the central Gondar zone, Ethiopia. One-hundred sixty swab samples were taken from animals that had been clinically suspected. The SeM gene was detected using polymerase chain reaction, and the antimicrobial susceptibilit...
McCarrel TM, Cole C, Maxwell LK, Roe HA, Morton AJ.To determine (1) the dose of liposomal bupivacaine (LB) to eliminate grade 2 of 5 lameness, the (2) duration of analgesia of LB versus bupivacaine hydrochloride (BH), and (3) LB pharmacokinetics versus BH. Methods: A reversible lameness model was validated in conditioned Thoroughbred horses (n = 12), aged 3 to 10 years. A dose-response trial compared subjective and objective lameness following abaxial sesamoid block with 25 mg BH/nerve or 30, 60, or 133 mg LB/nerve (n = 3/group). The LB dose that eliminated lameness and reduced lameness for the longest was used for blinded, randomized, crossov...
Hedberg Alm Y, Tydén E, Martin F, Lernå J, Halvarsson P.Selective anthelmintic treatment, advocated due to evolving anthelmintic resistance, has been associated with an increase in Strongylus vulgaris prevalence. Reverting to routine interval anthelmintic treatments is not viable and therefore, identifying other management factors correlated with S. vulgaris infection is vital. Objective: To investigate possible risk factors associated with the presence of S. vulgaris infection in resident horses on Swedish horse establishments. Methods: Internet-based questionnaire survey. Methods: A questionnaire, created using the internet-based survey platform ...
Kovács S, Bodó G, Tóth FZ, Néder L, Bakos Z.Potential arrhythmias recorded by cardiac monitors using the built-in human algorithm are as follows: total number of episodes, ventricular tachycardia, asystole, bradycardia, atrial tachycardia, atrial fibrillation and the percentage of time spent in atrial tachycardia or atrial fibrillation. Long-term use of an insertable cardiac monitor (loop recorder) has been reported in one horse earlier, but its accurate role as a diagnostic tool is still unclear. The aim of the present study was to investigate the long-term applicability of the Reveal XT cardiac monitor for recording cardiac arrhythmia...
Lindinger H, Wehrend A.Various systems are available for birth monitoring in horses, whereby a distinction must be made between methods for more accurate prediction of the date of birth in order to intensify monitoring of the mare in a timely manner as well as methods for detecting individuals that are in labor. Basically, it should be noted that there are almost no studies that compare different methods on the same population of mares. As the time of birth approaches, physiological parameters of mare and fetus change, but their variability is too high to predict the exact parturition time point prospectively. The b...
Tahir AM, Guo L, Ward RK, Yu X, Rideout A, Hore M, Wang ZJ.Laryngeal hemiplegia (LH) is a major upper respiratory tract (URT) complication in racehorses. Endoscopy imaging of horse throat is a gold standard for URT assessment. However, current manual assessment faces several challenges, stemming from the poor quality of endoscopy videos and subjectivity of manual grading. To overcome such limitations, we propose an explainable machine learning (ML)-based solution for efficient URT assessment. Specifically, a cascaded YOLOv8 architecture is utilized to segment the key semantic regions and landmarks per frame. Several spatiotemporal features are then ex...
Braid HR.In veterinary education, simulators are models or devices that can imitate a real patient or scenario and allow students to practice skills without the need for live patients. Castration is a common surgical procedure in all species, and the standing, open technique is frequently performed in horses. Although a simulator has been developed for equine closed castration, a simulator for standing castration in the horse has not yet been described. This two-part study focused on the design, creation, and evaluation of a simulator for teaching standing castration in the horse. A low-technology simu...
Carmona JU, Carmona-Ramírez LH, López C.(1) Background: There is increasing interest in the use of platelet-rich plasma and related orthobiologics for the treatment of chronic musculoskeletal disorders in horses; however, there is no information on the bibliometric impact of the literature published in this area. (2) Methods: A bibliometric analysis was performed using the bibliometrix R package by analyzing the documents registered in the WOS and Scopus databases from 2000 to 2024. The included registers were evaluated according to the menu of results from the biblioshiny web app (overview, sources, authors, documents, words, trend...
Hollis AR.Squamous cell carcinomas are a very common tumor type in horses, and are found in a variety of dermatologic and non-dermatologic locations. Metastasis is common, even at the first presentation of the disease, and a full staging workup is therefore strongly recommended to direct treatment and assist with prognostication. Wide surgical excision remains the treatment of choice in most cases, but recurrence is common, and adjunctive therapy may be indicated to improve the long-term prognosis.
Tomberg C, Petagna M, de Selliers de Moranville LA.Spontaneous eye blinks are brief closures of both eyelids. The spontaneous eye blink rate (SEBR) exceeds physiological corneal needs and is modulated by emotions and cognitive states, including vigilance and attention, in humans. In several animal species, the SEBR is modulated by stress and antipredator vigilance, which may limit the loss of visual information due to spontaneous eye closing. Here, we investigated whether the SEBR is modulated by attention in the domestic horse (Equus caballus). Our data supported previous studies indicating a tonic SEBR specific to each individual. We also fo...
Mudge MC, Green E.Radiotherapy is a valuable treatment option for equine tumors that have a high rate of recurrence or where complete surgical resection may damage vital structures. Teletherapy, brachytherapy, and plesiotherapy have been used successfully for the treatment of a variety of tumors and locations in the horse. Radiobiology, treatment protocols, side effects, and patient management are reviewed, with a focus on linear accelerator-based teletherapy. There is evidence of good success rates for treatment of periocular sarcoids and squamous cell carcinoma but teletherapy treatment is often limited to tu...
Holmes CM, Babasyan S, Eady N, Schnabel CL, Wagner B.Equine herpesvirus type 1 (EHV-1) is one of the most prevalent respiratory pathogens in horses with a high impact on animal health worldwide. Entry of the virus into epithelial cells of the upper respiratory tract and rapid local viral replication is followed by infection of local lymphoid tissues leading to cell-associated viremia and disease progression. Pre-existing mucosal immunity has previously been shown to reduce viral shedding and prevent viremia, consequently limiting severe disease manifestations. Here, nasopharyngeal transcriptomic profiling was used to identify differentially expr...
Al Mheiri FG, Joseph M, Joseph S, Alqassim M, Kinne J, Wernery U.This article describes the development of the pathogenic dimorphic fungus Histoplasma capsulatum var. farciminosum (HCF), which is the causative agent of Equine epizootic lymphangitis (EEL), from the mycelial form in the soil to the yeast form in the horse. In this study, the stages and morphology of HCF were identified through histopathological analysis and culture with various samples collected in Ethiopia from 15 horses showing clinical signs of EEL. In equids, especially cart horses in Ethiopia, poor-quality harnesses cause cutaneous wounds, which often attract flies facilitating the trans...
Di Salvo A, Chiaradia E, Sforna M, Della Rocca G.Since the discovery of the endocannabinoid system and due to the empirical evidence of the therapeutic effects on several illnesses both in humans and animals that follow the administration of exogenous cannabinoids (i.e., phytocannabinoids), numerous studies have been conducted. These investigations aimed to identify the expression and distribution of cannabinoid receptors in healthy and pathologic organs and tissues of different animal species and to define the interactions of phytocannabinoids with these receptors. In the last decade, pharmacokinetics, efficacy and tolerability of many Cann...
Veiga RF, Clarindo LN, Fensterseifer AL, Pompelli LH, Sfaciotte RAP, Schwarz DGG, Eloy LR, Ferraz SM.The objective of this study was to determine the prevalence of Streptococcus equi (S. equi subsp equi and S. equi subsp zooepidemicus) in the state of Santa Catarina and evaluate the antimicrobial susceptibility of the isolates. For this, 420 nasal swab samples were collected from randomly selected horses. Isolation and phenotypic characterization of the bacteria were performed by sowing on 5% sheep blood agar, followed by analysis of morphotinctorial characteristics and biochemical analysis. To differentiate the main beta-hemolytic Streptococcus in horses, the fermentation profiles of the sug...
Dyson S, Quiney L, Phillips K, Zheng S, Aleman M.Radiological observations at the cervicothoracic junction in horses with or without related clinical signs have not been comprehensively described. The aim was to evaluate the seventh cervical (C7) to second thoracic (T2) vertebrae in horses with neck-related clinical signs (neck pain and/or stiffness, neck-related forelimb lameness, or general proprioceptive [spinal] ataxia) and control horses. This prospective analytical cross-sectional study included 127 control horses and 96 cases, examined using standardized clinical and radiological protocols. Univariable logistic regression was used to ...
Johns LT, Smythe MP, Dewberry LS, Staiger EA, Allen K, Brooks SA.In international equestrian sport, visual inspections assess gait and lameness to protect the welfare of performance horses during competition. Horses competing internationally in three-day eventing must pass two mandatory inspections (pre-competition and post-cross country) before attempting the final phase: the jumping test (JT). We hypothesized that digitally quantifying objective gait parameters captured during the two mandatory inspections will identify locomotor characteristics that predict success during the jumping test. Utilizing the DeepLabCut (DLC) software package for labeling of a...
Mersich I, Wilkins PA.Gastrointestinal neoplasia is uncommon in horses. Clinical signs can be vague and advanced testing, including biopsy, exploratory surgery, and/or advanced imaging may be required for diagnosis. Prognosis varies by location, organ involved and is frequently poor to grave.
Ricard RM, Wobeser B. is a reported cause of infertility and endometritis in sheep, cattle, and pigs; however, the association between uterine disease and is poorly understood in horses. Recently, a high prevalence of in equine aborted chorioallantoises was reported in horses in western Canada. Based on this high prevalence, investigation into the effects of on infertility and endometritis in western Canadian mares is prudent. We examined 98 formalin-fixed, paraffin-embedded endometrial biopsies from western Canada submitted between 2014 and 2022 using a -specific 16S rRNA PCR test; 40 samples tested positive f...
Malalana F.Chemotherapy is the treatment of cancerous cells through the use of cytotoxic drugs. Whilst the use of systemic (intravenous) chemotherapy in equine practice is generally limited to the management of lymphoma, cytotoxic drugs are commonly used in the treatment of accessible skin tumors, either by topical application in the form of ointments or injected intralesionally. These drugs should be employed with caution due to the risk of serious adverse effects. In addition, extreme caution should be followed when preparing, handling, administering, and disposing them, due to their carcinogenic, muta...
Fukuda K, Mita H, Kuroda T, Tamura N, Kuwano A, Sato F, Takahashi T.To clarify the anti-inflammatory effect of platelet lysate (PL) on equine persistent synovitis by using a model of synovitis induced by monoiodoacetic acid (MIA). Methods: Nonseptic synovitis was induced by administering MIA into both antebrachiocarpal joints of 6 clinically healthy horses on day 0. On days 23, 30, and 37, carpal circumference measurement and synovial fluid collection for assays (leucocytes, LDH, tumor necrosis factor-α, and TGF-β1) were performed, after which PL was injected into 1 antebrachiocarpal joint and saline into the contralateral joint. Synovium and synovial fluid ...
Massacci FR, Clark A, Ruet A, Lansade L, Costa M, Mach N.Understanding gut microbiota similarities and differences across breeds in horses has the potential to advance approaches aimed at personalized microbial modifications, particularly those involved in improving sport athletic performance. Here, we explore whether faecal microbiota composition based on faecal 16S ribosomal RNA gene sequencing varies across six different sport breeds at two time points 8 months apart within a cohort of 189 healthy horses cared for under similar conditions. Lusitano horses presented the smallest and Hanoverians the greatest bacterial diversity. We found subtle bu...
Pérez DS, Tapia MO, Soraci AL.Fosfomycin (FOS) is a natural bactericidal broad-spectrum antibiotic which acts on proliferating bacteria by inhibiting cell wall and early murein/peptidoglycan synthesis. Bactericidal activity is evident against Gram positive and Gram negative bacteria and can also act synergistically with other antibiotics. Bacterial resistance to FOS may be natural or acquired. Other properties of this drug include inhibition of bacterial adhesion to epithelial cells, exopolysaccharide biofilm penetration, immunomodulatory effect, phagocytosis promotion and protection against the nephrotoxicity caused by ot...
Quintana AM, Landolt GA, Annis KM, Hussey GS.Our understanding of innate immunity within the equine respiratory tract is limited despite growing evidence for its key role in both the immediate defense and the shaping of downstream adaptive immune responses to respiratory disease. As the first interface to undergo pathogen invasion, the respiratory epithelium is a key player in these early events and our goal was to examine the innate immune characteristics of equine respiratory epithelia and compare them to an in vitro equine respiratory epithelial cell model cultured at the air-fluid interface (AFI). Respiratory epithelial tissues, isol...
Wagner AE.General anesthesia of horses entails considerable risk of morbidity and mortality. A large-scale, multicenter study reported that the death rate from non-colic-related anesthetics was 0.9%, while the perianesthetic mortality rate at a single, busy equine surgical practice was somewhat more favorable, at 0.12%. While any perianesthetic death is devastating, mortality figures alone do not reflect the overall morbidity of equine anesthesia in terms of nonterminal events or injuries related to recovery. In some circumstances, recognition of perianesthetic complications may allow appropriate interv...
Paras KL, George MM, Vidyashankar AN, Kaplan RM.Gastrointestinal nematode parasites are important pathogens of all domesticated livestock species. Fecal egg counts (FEC) are routinely used for evaluating anthelmintic efficacy and for making targeted anthelmintic treatment decisions. Numerous FEC techniques exist and vary in precision and accuracy. These performance characteristics are especially important when performing fecal egg count reduction tests (FECRT). The objective of this study was to compare the accuracy and precision of three commonly used FEC methods and determine if differences existed among livestock species. In this study, ...
Manohar M.Using radionuclide-labelled microspheres, 15 micron in diameter, we studied blood flow in the respiratory muscles (diaphragm and intercostal muscles), abdominal organs (adrenal glands, kidneys, pancreas, spleen and the small and large intestines), muscles of propulsion (gluteus medius and biceps femoris), and other working (triceps brachii and longissimus dorsi lumborum) and non-working (temporal and masseter) muscles of ponies at rest and during maximal exercise performed on a treadmill. During maximal exercise heart rate, whole body O2 consumption, cardiac output and mean aortic pressure inc...
Wagner B.Antibodies of the horse were studied intensively by many notable immunologists throughout the past century until the early 1970's. After a large gap of interest in horse immunology, additional basic studies on horse immunoglobulin genes performed during the past 10 years have resulted in new insights into the equine humoral immune system. These include the characterization of the immunoglobulin lambda and kappa light chain genes, the immunoglobulin heavy chain constant (IGHC) gene regions, and initial studies regarding the heavy chain variable genes. Horses express predominately lambda light c...
Pepys MB, Baltz ML, Tennent GA, Kent J, Ousey J, Rossdale PD.A sensitive and precise immunoassay for equine serum amyloid A protein (SAA) was established and used to determine, for the first time, the circulating concentration of this protein in health and disease. As in other species, equine SAA was present only at trace levels in healthy animals but behaved as an extremely sensitive and rapidly responding acute phase reactant following most forms of tissue injury, infection and inflammation, objectively reflecting the extent and activity of disease. Measurements of SAA should make a significant contribution to diagnosis and management of viral and bac...
Chang YF, Ku YW, Chang CF, Chang CD, McDonough SP, Divers T, Pough M, Torres A.The objective of this study is to determine whether doxycycline, ceftiofur or tetracycline could be effectively used to treat equine Lyme disease. Ponies experimentally infected with Borrelia burgdorferi by tick exposure were treated with doxycycline, ceftiofur or tetracycline for 4 weeks (28 days). Doxycyline and ceftiofur treatment were inconsistent in eliminating persistent infection in this experimental model. However, tetracycline treatment seems to eliminate persistent infection. Although serum antibody levels to B. burgdorferi in all ponies declined gradually after antibiotic treatment,...
LeBlanc MM, Magsig J, Stromberg AJ.Low-volume uterine flush (n=401) was performed in 308 infertile mares to diagnose endometritis. Mares evaluated were either barren after three or more breedings or had two or more unsuccessful embryo recovery attempts during consecutive cycles. Culture results were compared with cytological and histological findings, efflux clarity and pH to substantiate that the micro-organisms recovered were truly pathogens. Cytological specimens were evaluated for presence of epithelial and inflammatory cells, bacteria, yeast and debris. Endometrial biopsies (n=110) were examined for the presence of neutrop...
Johnson RJ, Rivard C, Lanaspa MA, Otabachian-Smith S, Ishimoto T, Cicerchi C, Cheeke PR, Macintosh B, Hess T.Fructose is a simple sugar present in honey and fruit, but can also exist as a polymer (fructans) in pasture grasses. Mammals are unable to metabolize fructans, but certain gram positive bacteria contain fructanases and can convert fructans to fructose in the gut. Recent studies suggest that fructose generated from bacteria, or directly obtained from the diet, can induce both increased intestinal permeability and features of metabolic syndrome, especially the development of insulin resistance. The development of insulin resistance is driven in part by the metabolism of fructose by fructokinase...
Newton JR, Townsend HG, Wood JL, Sinclair R, Hannant D, Mumford JA.Field outbreaks of influenza that occurred in vaccinated Thoroughbred racehorses in Newmarket in 1995 and 1996 were investigated by nucleoprotein ELISA and serology. Investigations showed that serum levels of vaccine-induced single radial haemolysis (SRH) antibody correlated closely with protective immunity against equine influenza and were consistent with observations made in previous experimental studies using nebulised aerosol challenge. In the second part of this study, antibody levels stimulated by vaccination were investigated to examine probable protection in high risk groups, such as y...
Goodrich LR, Phillips JN, McIlwraith CW, Foti SB, Grieger JC, Gray SJ, Samulski RJ.Osteoarthritis (OA) affects over 40 million people annually. We evaluated interleukin-1 receptor antagonist (IL-1ra) gene transfer in an equine model based on IL-1ra protein therapy which inhibits inflammation through blocking IL-1. Using the self-complementary adeno-associated virus (scAAV)IL-1ra equine gene as a starting construct, we optimized the transgene cassette by analyzing promoters (cytomegalovirus (CMV) versus chicken β-actin hybrid (CBh)), coding sequences (optimized versus unoptimized), vector capsid (serotype 2 versus chimeric capsid), and biological activity in vitro. AAV serot...
Merkies K, Franzin O.Horses () have been domesticated for millennia and are regularly utilized for work, sport, and companionship. Enhanced understanding of human-horse interactions can create avenues to optimize their welfare. This review explores the current research surrounding many aspects of human-horse interactions by first highlighting the horse's sensory capabilities and how they pertain to human interactions. Evidence exists that suggests that horses can read humans in various ways through our body odours, posture, facial expressions, and attentiveness. The literature also suggests that horses are capable...
Wilsher S, Allen WR.The normality of equine placentation is essential for fetal health and development. Substantial information exists on the gross morphological status of the placenta but few studies have addressed the problem of degenerative lesions that interfere with placental morphology and placental efficiency. Objective: Degenerative changes in the endometrium with increasing age and parity are reflected in the morphology and density of the placental microcotyledons. Objective: To assess placental efficiency on the basis of foal birthweight as a function of total microscopic area of fetomaternal contact. M...
Oaks JL, McGuire TC, Ulibarri C, Crawford TB.The equine infectious anemia virus (EIAV) often results in lifelong subclinical infection following early episodes of clinical disease. To identify the cellular reservoirs of EIAV during subclinical infection, horses were infected with EIAV and allowed to develop subclinical infections. Horses with acute disease served as a basis for comparison. The tissue distribution, replication status, location of infected cells, and viral load were characterized by PCR for proviral DNA and reverse transcriptase PCR for viral RNA, in situ hybridization, and in situ PCR. Proviral DNA was widespread in tissu...
Anthenill LA, Stover SM, Gardner IA, Hill AE.To assess individual and combined associations of high-speed exercise and horseshoe characteristics with risk of forelimb proximal sesamoid bone fractures and proximal sesamoid bone midbody fractures in Thoroughbred racehorses. Methods: 269 deceased Thoroughbred racehorses. Methods: A case-control study design was used to compare 121 horses with a fracture of at least 1 of 4 forelimb proximal sesamoid bones (75 horses had a midbody fracture) and 148 horses without a forelimb proximal sesamoid bone fracture. Univariable and multivariable logistic regression analyses were used to evaluate potent...
Locke M.Techniques for staining (silver, osmium, metal sulfides, ink) and microphotography (epi-illumination) of polished bone surfaces have been developed to visualize the three-dimensional structure of the shafts of mammalian long bones. Bone is a two-compartment system with capillaries and some kinds of connective tissue in one compartment separated from fibers of bone collagen, often forming lamellae, in the other. Laminar bone consists of stacks of lamellae separated by vascular spaces containing capillary network sheets. It is deposited at the periosteal and endosteal surfaces. Osteonic bone, we...
Johns IC, Baxter K, Booler H, Hicks C, Menzies-Gow N.To describe the bacterial and fungal flora of the normal conjunctiva of horses in the UK; to determine the effect of horse age, sex, geographic location, and housing on this flora; and to determine the most appropriate antimicrobial drug(s) for prophylactic treatment of corneal ulcers. Methods: A total of 60 adult healthy horses were studied. Methods: Swabs of the conjunctiva were obtained from 60 horses housed in two locations within the UK. Specimens were cultured for aerobic bacteria and fungi, and sensitivity against six ophthalmic antimicrobials assessed. The effect of age, sex, location ...
Troedsson MH.The objective of this article is to review the role of uterine defense mechanisms in natural resistance to chronic or persistent endometritis. A breakdown of uterine physical clearance mechanisms is currently believed to play a major role in susceptibility to persistent endometritis. Mares with increased susceptibility to persistent endometritis have impaired myometrial contractility in response to an acute inflammation, resulting in an accumulation of fluid and inflammatory products within the uterine lumen. The origin of this defect remains unknown. Recent studies have demonstrated that sper...
Arroyo LG, Rossi L, Santos BP, Gomez DE, Surette MG, Costa MC.The aim of this study was to compare the mucosal and luminal content microbiota of the cecum and colon of healthy and diarrheic horses. Marked differences in the richness and in the community composition between the mucosal and luminal microbiota of the cecum and large colon of horses with colitis were observed. Microbial dysbiosis occurs in horses with colitis at different levels of the intestinal tract, and microbiota composition is different between the mucosa and luminal content of diarrheic horses. The changes in some key taxa associated with dysbiosis in the equine intestinal microbiota,...
Griffin DJ, Bonnevie ED, Lachowsky DJ, Hart JC, Sparks HD, Moran N, Matthews G, Nixon AJ, Cohen I, Bonassar LJ.There has been much interest in using autologous chondrocytes in combination with scaffold materials to aid in cartilage repair. In the present study, a total of 27 animals were used to compare the performance of matrix-assisted chondrocyte implantation (MACI®) using a collagen sponge as a chondrocyte delivery vehicle, the sponge membrane alone, and empty controls. A total of three distinct types of mechanical analyses were performed on repaired cartilage harvested from horses after 53 weeks of implantation: (1) compressive behavior of samples to measure aggregate modulus (HA) and hydraulic p...
Lavoie-Lamoureux A, Leclere M, Lemos K, Wagner B, Lavoie JP.Systemic inflammation in horses with heaves is poorly characterized. Objective: To assess acute phase proteins (APP) and inflammatory cytokine profiles in serum of healthy horses and horses with heaves. Methods: Six healthy horses and 6 heaves-affected horses belonging to the University of Montreal. Methods: Prospective, observational study. Healthy and heaves-affected control horses were exposed to a 30-day natural challenge with hay and straw to induce clinical exacerbation of heaves. Serum samples were obtained by venipuncture before (T0) as well as after 7 (T7) and 30 days (T30) of stablin...
Johnston K, Holcombe SJ, Hauptman JG.To determine the relationship between plasma lactate concentration and colonic viability and survival in horses with >or=360 degrees volvulus of the ascending colon. Methods: Retrospective study. Methods: Horses (n=73) with >or=360 degrees volvulus of the ascending colon. Methods: Medical records (January 2000-November 2005) of all horses examined for colic at Michigan State University Veterinary Teaching Hospital were reviewed. Horses were included only if plasma lactate concentration was measured preoperatively and a diagnosis of >or=360 degrees volvulus of the ascending colon was c...
Tomlinson JE, Jager M, Struzyna A, Laverack M, Fortier LA, Dubovi E, Foil LD, Burbelo PD, Divers TJ, Van de Walle GR.Equine parvovirus-hepatitis (EqPV-H) has recently been associated with cases of Theiler's disease, a form of fulminant hepatic necrosis in horses. To assess whether EqPV-H is the cause of Theiler's disease, we first demonstrated hepatotropism by PCR on tissues from acutely infected horses. We then experimentally inoculated horses with EqPV-H and 8 of 10 horses developed hepatitis. One horse showed clinical signs of liver failure. The onset of hepatitis was temporally associated with seroconversion and a decline in viremia. Liver histology and in situ hybridization showed lymphocytic infiltrate...
Licka T, Frey A, Peham C.The pattern of electromyographic activity of the equine long back muscle at the walk has not yet been reported. The aim of this study was to use surface electromyography to measure activity of the longissimus dorsi muscles of horses walking on a treadmill. Fifteen horses without back pain were used and electromyographs were recorded bilaterally from the longissimus dorsi muscles at the level of T12, T16 and L3. Mean electromyograph activity and mean motion were calculated for each horse. At the walk, only one maximum activity for each longissimus dorsi muscle was detected during each motion cy...
Venter M, Pretorius M, Fuller JA, Botha E, Rakgotho M, Stivaktas V, Weyer C, Romito M, Williams J.During 2008-2015 in South Africa, we conducted West Nile virus surveillance in 1,407 animals with neurologic disease and identified mostly lineage 2 cases in horses (7.4%, 79/1,069), livestock (1.5%, 2/132), and wildlife (0.5%, 1/206); 35% were fatal. Geographic correlation of horse cases with seropositive veterinarians suggests disease in horses can predict risk in humans.
