Equine health encompasses the study and management of diseases, disorders, and overall well-being of horses. It involves understanding various physiological systems, preventive care, and treatment strategies to maintain optimal health in equine populations. Common areas of focus include nutrition, infectious diseases, orthopedic conditions, and reproductive health. Research in equine health aims to advance knowledge on diagnostic methods, therapeutic interventions, and management practices that improve horse welfare and performance. This page collects peer-reviewed research studies and scholarly articles that explore the diverse aspects of equine health, offering insights into current findings and advancements in the field.
Contreras MJ, Arias ME, Fuentes F, Muñoz E, Bernecic N, Fair S, Felmer R.Cryopreservation of stallion semen does not achieve the post-thaw quality or fertility results observed in other species like cattle. There are many reasons for this, but the membrane composition and intracellular changes in stallion sperm predispose them to low resistance to the cooling, freezing, and subsequent thawing process. Damage to the sperm results from different processes activated during cryopreservation, including oxidative stress, apoptosis, and structural modifications in the sperm membrane that increase the deleterious effect on sperm. In addition, significant individual variabi...
Southwood LL.Horses with colic caused by intestinal strangulation can have an excellent outcome with early surgical correction of the obstruction. The expense associated with surgery is typically less with early lesion correction. The challenge is making an early diagnosis of intestinal strangulation. Although for some horses with a strangulating obstruction, the need for surgery is made based on severe colic signs or lack of response to analgesia, in other horses, it is less obvious. Signalment, history, and meticulous physical examination, combined with some targeted diagnostic procedures can help with e...
Luethy D, Colmer S, Jodzio D, Bender S, Porter E, Hemmen Z, Fultz L, Craft W, Walker R, Johnson A, Holbrook T.Ultrasound-guided cervical centesis has gained popularity as a method for collecting cerebrospinal fluid (CSF) from standing horses. There are anecdotal reports of neck stiffness, regional swelling, sensitivity to palpation, and fever after the procedure. We report 2 horses with complications that occurred within days of C1-C2 centesis and ultimately resulted in euthanasia. Both C1-C2 centesis were performed routinely, with CSF cytologic analysis providing no evidence of blood contamination. Post-mortem examination revealed equine degenerative myeloencephalopathy as the primary disorder causin...
Reed SA, Streff LN.The field of equine sports medicine and rehabilitation provides a career opportunity for students interested in remaining in the horse industry but not focused on a career as a veterinarian. However, throughout the United States, there are limited educational opportunities for undergraduate students to prepare for this career. The objective of this work was to determine what skills and theoretical knowledge professionals in the equine rehabilitation industry deemed most useful for employment in the equine rehabilitation industry, and, using that information, develop a curriculum to meet these ...
Logan AA, Snyder AJ, Nielsen BD.The effects of gait and diameter have been studied independently, but rarely together in equine circular exercise studies. This study aimed to determine the impact of diameter (10-m or 15-m) at various gaits (walk, trot, and canter) on stride frequency or forelimb stance duration. Nine mature horses were outfitted with Tekscanâ„¢ Hoof Sensors on their forelimbs during circular and straight-line exercise at various gaits on a clay and sand arena surface. Statistical analysis was performed in SAS 9.4 with fixed effects of exercise type, recording, leg, and breed (PROC GLIMMIX, p < 0.05 significa...
Kaplan RM, Denwood MJ, Nielsen MK, Thamsborg SM, Torgerson PR, Gilleard JS, Dobson RJ, Vercruysse J, Levecke B.The faecal egg count reduction test (FECRT) remains the method of choice for establishing the efficacy of anthelmintic compounds in the field, including the diagnosis of anthelmintic resistance. We present a guideline for improving the standardization and performance of the FECRT that has four sections. In the first section, we address the major issues relevant to experimental design, choice of faecal egg count (FEC) method, statistical analysis, and interpretation of the FECRT results. In the second section, we make a series of general recommendations that are applicable across all animals ad...
Gysens L, Martens A, Haspeslagh M.Bovine papillomavirus (BPV) types 1 and 2 are causally associated with equine sarcoid, the most common mesenchymal neoplasm of horses, but the viral load (VL) differs between lesions. Sensitive and accurate BPV detection and quantification is essential for clinicians to confirm clinical suspicion, as well as in research settings for stratifying these skin lesions. Due to the limitations of histopathology in sarcoid diagnosis, PCR screening of superficial swabs constitutes the principal sampling method for BPV detection. This study aimed to investigate the ability of superficial swabs and fine-...
Rockow M, Griffenhagen G, Landolt G, Hendrickson D, Pezzanite L.In the past decade, there has been a considerable increase in the recognition of antimicrobial resistance in equine practice. The objective of this study was to survey the current clinical use of antimicrobials for a commonly performed surgical procedure (exploratory celiotomy) with the goal of understanding how recent literature and changes in microbial resistance patterns may have impacted antimicrobial selection practices. An electronic survey was distributed to veterinary professionals within the American College of Veterinary Internal Medicine (ACVIM) and the American College of Veterinar...
Guyard KC, Montavon S, Bertolaccini J, Deriaz M.Quantitative information on how well a horse clears a jump has great potential to support the rider in improving the horse's jumping performance. This study investigated the validation of a GPS-based inertial measurement unit, namely Alogo Move Pro, compared with a traditional optical motion capture system. Accuracy and precision of the three jumping characteristics of maximum height (Zmax), stride/jump length (lhorz), and mean horizontal speed (vhorz) were compared. Eleven horse-rider pairs repeated two identical jumps (an upright and an oxer fence) several times ( = 6 to 10) at different hei...
Chevalier JM, Pearson GB.The objective of this study was to report clinical outcomes of horses with naturally occurring full-thickness skin lacerations treated with an amorphous silicate dressing. We hypothesized that wounds treated with an amorphous silicate dressing would have minimal complications and lesion resolution without formation of exuberant granulation tissue. 11 client-owned horses. Clinical records of 11 horses with distal limb wounds treated with an amorphous silicate dressing were collected from participating veterinarians across the US. Wound healing progression was monitored by the veterinarian and o...
Aboashia FA, Alatrag F, Elmarimi A.Hematological and biochemical values are widely used in veterinary clinics for disease prognosis, nutritional and therapeutic monitoring, as well as in understanding the disease process in farm animals, including equines. This study aims to assess the alterations in hematological and biochemical parameters in pure Arabian horses infested with internal parasites. Samples of feces and blood were collected from 20 adult mares. Fecal samples were proceeded by flotation test. The blood samples were analyzed for hematological and biochemical parameters to determine their means ± standard error (M Â...
During husbandry, domestic animals are exposed to many factors that can influence their circadian physiology organization leading to an increase in animals' discomfort. Thermal homeostasis is at the basis of animal wellness, the aim of the present study was to investigate the daily fluctuation of serum concentrations of 3,5,3'-triiodothyronine (T3) and thyroxine (T4) in association with the daily fluctuation of uncoupling protein 1 (UCP1) and clock gene Per2 in healthy horses housed in individual box, to improve the knowledge on this matter. Seven clinically healthy female Italian Saddle horse...
Kendall A, Lützelschwab C, Lundblad J, Skiöldebrand E.Nerve growth factor (NGF) is a neurotrophin that is increased in osteoarthritic joints of horses. In humans, NGF has been associated with pain, and both synovial and serum NGF concentrations are increased in osteoarthritic patients. Studies in humans also have shown that serum NGF concentration can increase with stress. Serum NGF concentration should be evaluated in horses with osteoarthritis-associated lameness. Objective: Quantify and compare serum NGF concentration in horses with osteoarthritis-associated lameness and sound horses. Additionally, the impact of short-term stress on serum NGF ...
Anwaar F, Ijaz M, Rasheed H, Shah SFA, Haider SAR, Sabir MJ.The purpose of the current study was to investigate the nasal colonization and drug resistance profile of Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), and vancomycin-resistant S. aureus (VRSA) in donkeys (n =63), mules (n = 42), and horses (n = 98). MRSA and VRSA were confirmed based on phenotypic and molecular methods, followed by phylogenetic analysis. Furthermore, the association of various animal and management-based risk factors with S. aureus colonization was also evaluated. The presence of nuc gene on polymerase chain reaction showed an overall prevalence of 42.86%...
Pimenta J, Pinto AR, Saavedra MJ, Cotovio M.Horses are considered as reservoirs of multidrug resistant bacteria that can be spread through the environment and possibly to humans. The aim of this study was to characterize the oral Gram-negative microbiota of healthy horses and evaluate their antimicrobial susceptibility profile in a One Health approach. For this purpose, samples were collected from the gingival margin of healthy horses, free of antimicrobial therapy, cultured in selective mediums, identified, and tested for antimicrobial susceptibility. Fifty-five Gram-negative isolates were identified, with 89.5% being zoonotic and 62% ...
Bampidis V, Azimonti G, Bastos ML, Christensen H, Durjava M, Dusemund B, Kouba M, López-Alonso M, López Puente S, Marcon F, Mayo B, Pechová A....Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of DBVPG 48 SF (BioCell®) as a zootechnical feed additive for horses, pigs and ruminants. The product, manufactured in three formulations (microsphere, micropellet and powder), is intended for use in complete feed at a minimum inclusion level of 3 × 10 CFU/kg complete feed for horses, 4 × 10 CFU/kg complete feed for dairy cows and minor dairy species, 4 × 10 CFU/kg complete feed for calves, cattle for fattening, minor growing and fattening ruminants...
Kumbhani TR, Raval SH, Parmar RS, Patel JG, Bechara VJ, Sindhi PI, Modh SP.A 6-year-old Marwari mare presented with recurrent vulvar growth. The growth was surgically excised, fixed and processed routinely. Microscopically, neoplasm showed proliferation of epithelial and myoepithelial cells with tubulopapillary pattern. On immunohistochemistry, myoepithelial cells showed strong immunoreactivity with smooth muscle actin alpha and p63. On basis of histopathology and immunohistochemistry, tumour was diagnosed as complex apocrine carcinoma. This case report describes first confirm vulvar complex apocrine carcinoma in equines.
Zollinger A, Wyss C, Bardou D, Bachmann I.In domestic conditions, adult stallions are mostly housed individually in internal stables to reduce the risk of injuries during social interactions. Social deprivation in horses results in physiological stress and behavioural problems. The aim of this study was to test the "social box" (SB), which allows closer physical contact between neighbouring horses. Eight pairs of stallions (n = 16) were filmed over a 24 h period in the SB and in their usual box stables, "conventional boxes" (CB), which strongly restrict tactile contact. The effect of housing in the SB on behaviour and the occurrence a...
Bampidis V, Azimonti G, Bastos ML, Christensen H, Durjava M, Kouba M, López-Alonso M, López Puente S, Marcon F, Mayo B, Pechová A, Petkova M....Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of anise oil and anise tincture obtained from the fruit of L., when used as sensory additives. The use of the anise oil at the proposed use level in complete feed of 1.9 mg/kg for laying hens and 5 mg/kg for horses was considered of low concern. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) had no safety concern when anise oil is used at the proposed use levels of 1.5 mg/kg for chickens for fattening and at 1.7 mg/kg for turk...
Bampidis V, Azimonti G, Bastos ML, Christensen H, Dusemund B, Durjava M, Kouba M, López-Alonso M, López Puente S, Marcon F, Mayo B, Pechová A....Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on DSM 11520 when used as a technological additive (acidity regulator) in feed for horses, dogs, cats and pet rabbits. The additive is intended to be incorporated into oat-derived products (ca. 55% moisture content), carrot root-derived products (≥ 90% moisture) and coconut flesh-derived products (≥ 90% moisture) at a minimum inclusion level of 8.0 × 10 CFU/kg of the feed material under scope. The bacterial species is considered by EFSA to be suitable for the qualified presumption ...
Schade J, de Souza AF, Vincensi LC, Müller TR, Fonteque JH.The objective of this study was to evaluate and compare the sonographic characteristics of the digital flexor tendons and ligaments of the palmar/plantar of the metacarpal and metatarsal regions in gaited horses, as well as to establish normal reference ultrasound values for Mangalarga Marchador (MM) and Campeiro breeds. Transverse sonographic images were obtained of 50 adult and healthy horses from the MM (n = 25) and Campeiro (n = 25) breeds. The images were taken in six metacarpal/metatarsal zones, and the following measurements were taken: transverse area, circumference, dorsopalmar/planta...
Costa PWL, Oliveira CSM, Bezerra RA, Alvares FBV, Formiga VHAS, Martins MRDD, Feitosa TF, Vilela VLR.The aim of this study was to describe the prevalence of anti- and anti- antibodies in equids that carry out traction work in Northeastern Brazil, and to establish the potential risk factors associated with seropositivity for these agents. Blood samples were collected from 322 traction equids (horses, donkeys and mules) in urban areas of 16 municipalities in the State of ParaÃba, Brazil. The samples were sent for serological diagnosis using the Immunofluorescence Antibody Test (IFAT). Epidemiological questionnaires were given to the owners to assess the possible risk factors associated with in...
Ermers C, McGilchrist N, Fenner K, Wilson B, McGreevy P.Failure to meet the minimum forage requirement of 1.5% of the horse's bodyweight and the opportunity for foraging for a minimum of 8 h a day (not going without this opportunity longer than four to five consecutive hours) can have both physiological and behavioural consequences. To provide an energy source for horses, rations often include starch rather than fibre. This can result in health issues related to the gastrointestinal tract (GIT) in the horse. In the stomach, the main concern is equine gastric ulcer syndrome (EGUS) and, more specifically, equine squamous gastric disease (ESGD). Ulcer...
Chalvignac L, Galia P, Faure P, Prieto N.For several years, animal-mediated therapies have been used in the treatment of psychiatric patients. Post-traumatic stress disorder has the particularity of being generated by an external event in a person a priori free of mental pathology. In this disorder, various so-called targeted psychotherapies have proven to be effective, including equine therapy.
Liehrmann O, Cosnard C, Riihonen V, Viitanen A, Alander E, Jardat P, Koski SE, Lummaa V, Lansade L.Cues such as the human pointing gesture, gaze or proximity to an object are widely used in behavioural studies to evaluate animals' abilities to follow human-given cues. Many domestic mammals, such as horses, can follow human cues; however, factors influencing their responses are still unclear. We assessed the performance of 57 horses at a two-way choice task testing their ability to follow cues of either a familiar (N = 28) or an unfamiliar informant (N = 29). We investigated the effects of the length of the relationship between the horse and a familiar person (main caregiver), their ...
Suniga PAP, Mantovani C, Santos MG, Rieger JSG, Gaspar EB, Dos Santos FL, Mota RA, Chaves KP, Egito AA, Filho JCO, Nassar AFC, Dos Santos LR....Glanders is a contagious disease of equids caused by the Gram-negative bacterium Burkholderia mallei. In Brazil, the disease is considered to be reemerging and has been expanding, with records of equids with positive serology in most of the federative units. However, there are few reports describing the genotypic detection of the agent. This study demonstrated the detection of B. mallei by species-specific PCR directly from tissues or from bacterial cultures, followed by amplicon sequencing in equids (equines, mules, and asinines) with positive serology for glanders in all five geographic regi...
Wong KS, Cheung HW, Szeto CWL, Tsang CYN, Wan TSM, Ho ENM.Illicit administration of transgene into horses is a form of gene doping that has been a key concern in equine sports. The large number of potential performance-enhancing transgenes has demanded a cost-effective and reliable detection method. Multiplex qPCR is a relevant technique, but the cross-talking between fluorophores and high background noise limits the method sensitivity and specificity. This study reports a simpler multiplexing approach by using the same fluorophore for four hydrolysis probes each targeting one of the four transgenes: human growth hormone, insulin-like growth factor 1...
Chalder R, Housby-Skeggs N, Clark C, Pollard D, Hartley C, Blacklock B.There are a growing number of horses, ponies, and donkeys aged 15 years or older in the United Kingdom, yet there have been no studies utilising a complete ophthalmic examination to investigate the prevalence of ophthalmic pathology within this population. Objective: To investigate the prevalence of ophthalmic pathology and associations with signalment, in a convenience sample of geriatric equids in the United Kingdom. Methods: Cross sectional. Methods: Horses, ponies, and donkeys aged 15 years or older based at The Horse Trust charity underwent a full ophthalmic examination including slit...
McGivney BA, Browne JA, Fonseca RG, Katz LM, Machugh DE, Whiston R, Hill EW.Myostatin, encoded by the MSTN gene, is a member of the TGF-β superfamily that regulates skeletal muscle development. A MSTN SNP significantly associated with Thoroughbred horse racing phenotypes has recently been identified as well as significant reductions in Thoroughbred skeletal muscle gene expression for three transcripts 400-1500 base pairs downstream of the MSTN gene following a period of training. Together, these findings indicate that MSTN genotypes may influence MSTN gene expression. To investigate this, MSTN mRNA expression was measured in biopsies from the middle gluteal muscle fr...
Moore AI, Squires EL, Graham JK.Seminal plasma is generally removed from equine spermatozoa prior to cryopreservation. Two experiments were designed to determine if adding seminal plasma back to spermatozoa, prior to cryopreservation, would benefit the spermatozoa. Experiment 1 determined if different concentrations of seminal plasma affected post-thaw sperm motility, viability and acrosomal integrity of frozen/thawed stallion spermatozoa. Semen was washed through 15% Percoll to remove seminal plasma and spermatozoa resuspended to 350 x 10(6)sperm/mL in a clear Hepes buffered diluent containing either 0, 5, 10, 20, 40 or 80%...
Speake PF, Roberts CA, Gibson JS.K influx into equine red blood cells (RBCs) was measured using 86Rb as a tracer for K under conditions designed to mimic the changes in respiratory blood parameters that occur in vivo during strenuous exercise. The effects on K influx of physiological changes in pH, cell volume, O2 tension (PO2), CO2 tension (PCO2), and bicarbonate and lactate concentrations were defined. Physiological PO2 exerted a dominant controlling influence on the H(+)-stimulated Cl-dependent K influx, consistent with effects on the K-Cl cotransporter, PO2 required for half-maximal activity was 37 +/- 3 mmHg (4.9 kPa). A...
Moore RM, Muir WW, Granger DN.Restoration of blood flow after a period of intestinal ischemia is necessary to maintain cell function and viability; however, the reintroduction of oxygen can initiate a cascade of events that exacerbates tissue injury. Intestinal I-R injury is manifested as increased microvascular and mucosal permeability, and mucosal necrosis. Reperfusion injury begins with the accumulation of hypoxanthine from ATP metabolism and the conversion of XDH to XO during ischemia. Upon reperfusion, the XO catalyzes the conversion of hypoxanthine to superoxide radicals in the presence of oxygen. Superoxide radicals...
Nielsen TD, Dean RS, Robinson NJ, Massey A, Brennan ML.The practice of evidence-based veterinary medicine involves the utilisation of scientific evidence for clinical decision making. To enable this, research topics pertinent to clinical practice need to be identified, and veterinary clinicians are best placed to do this. The main aim of this study was to describe the veterinary population, the common species and conditions veterinary clinicians nominated they saw in practice and how much information clinicians perceived was available in the literature for these. A questionnaire was distributed to all Royal College of Veterinary Surgeons registere...
Olive J, D'Anjou MA, Alexander K, Laverty S, Theoret C.We compared the ability of 1.5 T magnetic resonance imaging (MRI), computed tomography (CT), and computed radiography (CR) to evaluate noncartilaginous structures of the equine metacarpophalangeal joint (MCP), and the association of imaging changes with gross cartilage damage in the context of osteoarthritis. Four CR projections, helical single-slice CT, and MRI (Ti-weighted gradient recalled echo [GRE], T2*-weighted GRE with fast imaging employing steady-state acquisition [FIESTA], T2-weighted fast spin echo with fat saturation, and spoiled gradient recalled echo with fat saturation ISPGR-FS]...
Firestone SM, Cogger N, Ward MP, Toribio JA, Moloney BJ, Dhand NK.The influences of relative humidity and ambient temperature on the transmission of influenza A viruses have recently been established under controlled laboratory conditions. The interplay of meteorological factors during an actual influenza epidemic is less clear, and research into the contribution of wind to epidemic spread is scarce. By applying geostatistics and survival analysis to data from a large outbreak of equine influenza (A/H3N8), we quantified the association between hazard of infection and air temperature, relative humidity, rainfall, and wind velocity, whilst controlling for prem...
Mueller RS, Jensen-Jarolim E, Roth-Walter F, Marti E, Janda J, Seida AA, DeBoer D.In human patients with seasonal allergic rhinoconjunctivitis sensitized to grass pollen, the first successful allergen immunotherapy (AIT) was reported in 1911. Today, immunotherapy is an accepted treatment for allergic asthma, allergic rhinitis and hypersensitivities to insect venom. AIT is also used for atopic dermatitis and recently for food allergy. Subcutaneous, epicutaneous, intralymphatic, oral and sublingual protocols of AIT exist. In animals, most data are available in dogs where subcutaneous AIT is an accepted treatment for atopic dermatitis. Initiating a regulatory response and a pr...
Isgren CM, Edwards T, Pinchbeck GL, Winward E, Adams ER, Norton P, Timofte D, Maddox TW, Clegg PD, Williams NJ.This study investigated changes over time in the epidemiology of extended-spectrum β-lactamase (ESBL) producing Escherichia coli within a single equine referral hospital in the UK. Faecal samples were collected from hospitalised horses in 2008 and 2017, processed using selective media and standard susceptibility laboratory methods. A novel real-time PCR with high resolution melt analysis was used to distinguish bla and bla within CTX-M-1 group. Results: In 2008, 457 faecal samples from 103 horses were collected, with ESBL-producing E. coli identified in 131 samples (28.7, 95% CI 24.6-33.1). I...
Chateau H, Holden L, Robin D, Falala S, Pourcelot P, Estoup P, Denoix JM, Crevier-Denoix N.Sandy beaches are often considered good training surfaces for trotter horses. However, their biomechanical effects on locomotion are insufficiently documented. Events at hoof impact have mostly been studied under laboratory conditions with accelerometers, but there is lack of data (acceleration, force, movement) on events occurring under every day practical conditions in the field. Objective: To investigate hoof landing and stride parameters on different tracks (from wet to dry) of a sand beach and on an asphalt road. Methods: The right front hoof of 4 trotter horses was equipped with a triaxi...
Aurich C.The majority of horse registries approve the use of artificial insemination, and horse breeding has widely taken benefit from the use of cooled-stored semen. New insights into cooled-semen technology open possibilities to reduce problems such as impaired semen quality after cooled-storage in individual stallions. The stallion itself has major impacts on quality and fertility of cooled-stored semen. Dietary supplementation of antioxidants and polyunsaturated fatty acids improves semen quality in a variety of species, but only few studies on this topic exist in the horse. Proper semen collection...
Toutain PL, Autefage A, Legrand C, Alvinerie M.The purpose of the present study was to establish in the horse the relationship between plasma concentration profiles of phenylbutazone (PBZ) and flunixin meglumine (FM) and their pharmacological effects in order to build a predictive pharmacokinetic/pharmacodynamic (PK/PD) model. In five horses, an experimental arthritis was induced by injecting Freund's adjuvant into a carpal joint. PBZ (4 mg/kg) and FM (1 mg/kg) were injected by the intravenous route as a single intravenous dose in two different trials. Five pharmacodynamic end-points were regularly measured after test article injection usi...
Ostlund EN, Andresen JE, Andresen M.WNV encephalitis in horses, previously reported in Africa, Asia, and Europe, occurred for the first time in the Western Hemisphere in 1999. The causative agent, WNV, is a flavivirus maintained in nature by a bird-mosquito cycle. The disease in horses is manifested primarily by ataxia of variable severity. Outbreaks of encephalitis may have a case fatality rate in excess of 40%, although this virus infection is inapparent in some horses. Early evidence indicates that WNV has overwintered in the northeastern United States and poses a threat for future disease occurrences in horses. No vaccine is...
Papas M, Catalán J, Fernandez-Fuertes B, Arroyo L, Bassols A, Miró J, Yeste M.While the removal of seminal plasma is a routine practice prior to equine sperm cryopreservation, this fluid contains the main source of antioxidant enzymes able to scavenge these reactive oxygen species. Therefore, stallion seminal plasma components may have an impact on ejaculate freezability. Against this background, this study was designed to investigate whether the activities of the main stallion seminal plasma antioxidant enzymes are related to sperm cryotolerance. With this purpose, 16 ejaculates were collected from 14 healthy stallions, and each ejaculate was split into two aliquots. T...
Piras FM, Nergadze SG, Poletto V, Cerutti F, Ryder OA, Leeb T, Raimondi E, Giulotto E.Horses, asses and zebras belong to the genus Equus and are the only extant species of the family Equidae in the order Perissodactyla. In a previous work we demonstrated that a key factor in the rapid karyotypic evolution of this genus was evolutionary centromere repositioning, that is, the shift of the centromeric function to a new position without alteration of the order of markers along the chromosome. In search of previously undiscovered evolutionarily new centromeres, we traced the phylogeny of horse chromosome 5, analyzing the order of BAC markers, derived from a horse genomic library, in...
Yuan ZQ, Gault EA, Gobeil P, Nixon C, Campo MS, Nasir L.It is now widely recognized that BPV-1 and less commonly BPV-2 are the causative agents of equine sarcoids. Here we present the generation of equine cell lines harboring BPV-1 genomes and expressing viral genes. These lines have been either explanted from sarcoid biopsies or generated in vitro by transfection of primary fibroblasts with BPV-1 DNA. Previously detected BPV-1 genome variations in equine sarcoids are also found in sarcoid cell lines, and only variant BPV-1 genomes can transform equine cells. These equine cell lines are morphologically transformed, proliferate faster than parental ...
Vaz PK, Horsington J, Hartley CA, Browning GF, Ficorilli NP, Studdert MJ, Gilkerson JR, Devlin JM.Recombination in alphaherpesviruses allows evolution to occur in viruses that have an otherwise stable DNA genome with a low rate of nucleotide substitution. High-throughput sequencing of complete viral genomes has recently allowed natural (field) recombination to be studied in a number of different alphaherpesviruses, however, such studies have not been applied to equine herpesvirus 1 (EHV-1) or equine herpesvirus 4 (EHV-4). These two equine alphaherpesviruses are genetically similar, but differ in their pathogenesis and epidemiology. Both cause economically significant disease in horse popul...
Tanhauser SM, Yowell CA, Cutler TJ, Greiner EC, MacKay RJ, Dame JB.Studies designed to investigate the causative agent of equine protozoal myeloencephalitis and its life cycle have been hampered by the marked similarity of Sarcocystis neurona to other Sarcocystis spp. present in the same definitive host. Random-amplified polymorphic DNA techniques were used to amplify DNA from isolates of S. neurona and Sarcocystis falcatula. DNA sequence analysis of polymerase chain reaction (PCR) products was then used to design PCR primers to amplify specific Sarcocystis spp. DNA products. The ribosomal RNA internal transcribed spacer was also amplified and compared betwee...
Textor J.Autologous biologic therapies such as platelet-rich plasma and autologous conditioned serum are in widespread clinical use to treat musculoskeletal pathology in horses. These substances exert a therapeutic effect through the provision of either anabolic or anti-catabolic factors, or a combination of both. This article discusses the history, experimental and clinical literature, and currently accepted preparation and usage strategies for both platelet-rich plasma and autologous conditioned serum.
Brinsko SP, Varner DD, Love CC, Blanchard TL, Day BC, Wilson ME.Eight stallions were used in 2 x 2 crossover study to determine if feeding a nutriceutical rich in docosahexaenoic acid (DHA) would improve semen quality. Stallions were randomly assigned to one of two treatment groups (n = 4 per group). Stallions were fed their normal diet (control) or their normal diet top-dressed with 250 g of a DHA-enriched nutriceutical. Feeding trials lasted for 14 week, after which a 14-week washout period was allowed and the treatment groups were reversed for another 14 week feeding trial. Feeding the nutriceutical resulted in a three-fold increase in semen DHA levels ...
Kayar SR, Hoppeler H, Mermod L, Weibel ER.Individual mitochondria were reconstructed from ultrathin serial sections of selected muscle fibers in the M. semitendinosus of a horse, over a length of nearly two sarcomeres. Mitochondria were found to be highly variable, with size and complexity of single mitochondria increasing with the fractional part of a fiber occupied by mitochondria. In fibers with a mitochondrial volume density of less than 4%, corresponding to the mitochondrial content of fast-twitch glycolytic fibers, mitochondria were generally rather simple cylindrical shapes, oriented parallel to the myofibrils. In fibers with a...
Kamerling JP, Vliegenthart JF.A number of O-acetylated N-acylneuraminic acids, isolated from submandibular glands of cow and horse and from horse erythrocytes, have been characterized by mass spectrometry. On the basis of the typical fragmentation patterns of the pertrimethylsilyl derivatives of the methyl esters of the compounds, they were identified as 4-O-acetyl-, 9-O-acetyl-, 4,9-di-O-acetyl-, and 7,9-di-O-acetyl N-acetylneuraminic acid, and 4-O-acetyl-and 9-O-acetyl-N-glycolylneuraminic acid.
Martin G, Plowright R, Chen C, Kault D, Selleck P, Skerratt LF.Hendra virus (HeV) is lethal to humans and horses, and little is known about its epidemiology. Biosecurity restrictions impede advances, particularly on understanding pathways of transmission. Quantifying the environmental survival of HeV can be used for making decisions and to infer transmission pathways. We estimated HeV survival with a Weibull distribution and calculated parameters from data generated in laboratory experiments. HeV survival rates based on air temperatures 24 h after excretion ranged from 2 to 10 % in summer and from 12 to 33 % in winter. Simulated survival across the distri...
Goodson J, Tyznik WJ, Cline JH, Dehority BA.Microbial numbers, pH, fluid volume, and turnover rate in the pony cecum were measured during an abrupt change from an all-forage to an all-concentrate diet, both fed at maintenance energy levels. Concentrate feeding resulted in increased (P less than 0.01) numbers of total viable anaerobic bacteria. The numbers of organisms growing on selective starch medium increased (P less than 0.01) when concentrate was fed, while numbers on xylan and pectin media decreased (P less than 0.025). Seven days after the diet change to concentrate, the number of bacteria growing on lactate medium increased (P l...
Vance SJ, McDonald RE, Cooper A, Smith BO, Kennedy MW.Latherin is a highly surface-active allergen protein found in the sweat and saliva of horses and other equids. Its surfactant activity is intrinsic to the protein in its native form, and is manifest without associated lipids or glycosylation. Latherin probably functions as a wetting agent in evaporative cooling in horses, but it may also assist in mastication of fibrous food as well as inhibition of microbial biofilms. It is a member of the PLUNC family of proteins abundant in the oral cavity and saliva of mammals, one of which has also been shown to be a surfactant and capable of disrupting m...
Skedros JG, Su SC, Bloebaum RD.Artiodactyl and perissodactyl calcanei have been recently introduced as models for examining bone for mechanically mediated adaptation. We have reported substantial regional variations in cortical bone microstructure and mineral content within the same cross-section of mule deer calcanei. In part, these variations may be adaptations accommodating the customary presence of predominantly tension, compression, and shear strain modes in mutually exclusive cortical locations. Calcanei from skeletally mature horses, elk, and sheep were examined in order to corroborate these previous findings. From e...
Dhondt KP, Horvat B.The Henipavirus genus contains two highly lethal viruses, the Hendra and Nipah viruses and one, recently discovered, apparently nonpathogenic member; Cedar virus. These three, negative-sense single-stranded RNA viruses, are hosted by fruit bats and use EphrinB2 receptors for entry into cells. The Hendra and Nipah viruses are zoonotic pathogens that emerged in the middle of 90s and have caused severe, and often fatal, neurologic and/or respiratory diseases in both humans and different animals; including spillover into equine and porcine species. Development of relevant models is critical for a ...
Rowland AL, Miller D, Berglund A, Schnabel LV, Levine GJ, Antczak DF, Watts AE.Allogeneic mesenchymal stromal cells (MSCs) have been used clinically for decades, without cross-matching, on the assumption that they are immune-privileged. In the equine model, we demonstrate innate and adaptive immune responses after repeated intra-articular injection with major histocompatibility complex (MHC) mismatched allogeneic MSCs, but not MHC matched allogeneic or autologous MSCs. We document increased peri-articular edema and synovial effusion, increased synovial cytokine and chemokine concentrations, and development of donor-specific antibodies in mismatched recipients compared wi...
Geary TG, Sangster NC, Thompson DP.Research in anthelmintic pharmacology faces a grim future. The parent field of veterinary parasitology has seemingly been devalued by governments, universities and the animal industry in general. Primarily due to the success of the macrocyclic lactone anthelmintics in cattle, problems caused by helminth infections are widely perceived to be unimportant. The market for anthelmintics in other host species that are plagued by resistance, such as sheep and horses, is thought to be too small to sustain a discovery program in the animal health pharmaceutical industry. These attitudes are both alarmi...
