Equine diseases encompass a wide range of health conditions that can affect horses, including infectious diseases, metabolic disorders, and genetic conditions. These diseases can impact the overall health, performance, and well-being of horses. Common equine diseases include equine influenza, equine herpesvirus, laminitis, and equine metabolic syndrome. Diagnosis and management of these diseases often require a combination of clinical evaluation, laboratory testing, and appropriate treatment strategies. This page gathers peer-reviewed research studies and scholarly articles that explore the etiology, pathophysiology, diagnosis, and treatment options for various equine diseases, providing valuable insights for veterinarians and researchers in the field.
Mohtasebi S, Ahn S, Rosa B, Moyes K, Kuzmina TA, Gilleard JS, Poissant J.Equids are infected by a diversity of gastrointestinal nematode parasites, including 64 species of equine strongyle nematodes from19 genera. Despite numerous surveys of horse strongyles worldwide, certain geographic regions and rare species remain understudied. In 1964, a new species of equine strongyle, Cylicocyclus pekingensis, was described from a donkey in China. Subsequently, this species was recorded in horses from Kazakhstan and reclassified as Hsiungia pekingensis (K'ung and Yang, 1964), the only species in this genus. Since then, H. pekingensis has not been reported elsewhere, with li...
Sheahan BJ, Schubert AG, Schubert W, Sheats MK, Schnabel LV, Gilbertie JM.Neutrophil extracellular traps (NETs) play a significant role in response to a variety of infectious and inflammatory stimuli in human and veterinary medicine. Although entrapment of bacteria can be an important function of NETs, the exuberant release of DNA and other intracellular molecules has also been negatively implicated in the pathogenesis of different diseases. Thus, NET formation must be tightly controlled and represents an opportunity for therapeutic interventions. Horses are particularly sensitive to bacterial stimuli that have previously been shown to cause NETs in other species, b...
Entwisle IG, McConnell EJ.Sand enteropathy describes the clinical signs attributed to accumulation of sand in the gastrointestinal tract. Psyllium combined with magnesium sulphate has been recommended for clearing intestinal sand, but this has only been evaluated in one population. The combination of these two agents with paraffin oil has not been investigated. Objective: To investigate the effectiveness of paraffin oil, psyllium and magnesium sulphate combined in clearing intestinal sand in horses diagnosed with sand enteropathy. Methods: Retrospective case series. Methods: Medical records of horses presenting for san...
Botía M, Muñoz-Prieto A, Martínez-Subiela S, Martín-Cuervo M, Hansen S, Manteca X, Cerón JJ, López-Arjona M.Equine gastric ulcer syndrome (EGUS) is a frequent disease in horses that comprises two different entities: equine squamous gastric disease (ESGD) and equine glandular gastric disease (EGGD). This disease considerably reduces the quality of life of affected horses and can negatively affect performance. Saliva contains biomarkers, such as oxytocin, that have been used as a welfare indicator and can develop a function as a protective factor against stress-induced changes in gastric function due to its gastric antisecretory and antiulcer effects. The objective of this work was to evaluate changes...
Gillen A, Archer D, Ireland J, Rocchigiani G.Strangulating lipomata are the most common cause of small intestinal strangulating obstruction. Evaluation of histological features of pathological and non-pathological lipomata, and the histological properties of omental and retroperitoneal fat have not been described. Objective: To characterise histological features of equine abdominal lipomata, omental and retroperitoneal adipose tissue, and associations between them. Methods: Prospective observational anatomic (gross and histological). Methods: Horses undergoing emergency laparotomy for management of abdominal pain in a single hospital wer...
Anderson JR, Phelan MM, Caamaño-Gutiérrez E, Clegg PD, Rubio-Martinez LM, Peffers MJ.Equine osteoarthritis (OA) is predominantly diagnosed through clinical examination and radiography, leading to detection only after significant joint pathology. The pathogenesis of OA remains unclear and while many medications modify the disease's inflammatory components, no curative or reversal treatments exist. Identifying differentially abundant metabolites and proteins correlated with osteoarthritis severity could improve early diagnosis, track disease progression, and evaluate responses to interventions. Objective: To identify molecular markers of osteoarthritis severity based on histolog...
Adler DMT, Nielsen AT, Olsen C, Verwilghen D, Damborg P, Olsen RH.To investigate the in vitro efficacy of antibiotics (amikacin, ceftiofur, and gentamicin) in combination with local anesthetics (LAs; bupivacaine hydrochloride, lidocaine hydrochloride, and mepivacaine hydrochloride), a combination commonly performed for IA injectate and regional limb perfusion (RLP) in horses. Unassigned: 17 equine clinical isolates were tested by the checkerboard method for their minimum inhibitory concentration (MIC) against a combination of concentrations of LAs and antibiotics from August 2020 through December 2023. Unassigned: For the majority of combinations, the antibi...
Engiles JB, Stefanovski D, van Eps A.To examine the effects of prolonged preferential weight bearing (PWB) and reduced ambulation (RA) on hoof lamellae using a nonpainful in vivo experimental model. Unassigned: 12 healthy Standardbred horses were housed in stocks continuously for 92 hours. A platform shoe was placed on 1 forelimb in the PWB group (n = 6) to increase the load on the supporting limb (SL) by approximately 10% bodyweight, whereas the RA group (n = 6) had normal weight bearing. Archived healthy horse (n = 8) samples were used as controls. Histomorphometry and histochemistry (terminal deoxynucleotidyl transferase dUTP ...
Fernandes TA, Paulino PG, Dos Santos Juliano D, Rabello CA, de Oliveira NVB, de Souza Santana M, Peckle M, Massard CL, da Costa Angelo I, Jacob JCF....Equine piroplasmosis (EP) is a reportable disease according to the World Organization for Animal Health (WOAH), caused by Babesia caballi, Theileria equi and T. haneyi. This syndrome is prevalent in tropical and subtropical regions, including various areas in Brazilian. This study examines EP in the Distrito Federal, Brazil, focusing on prevalence, epidemiological characteristics, and circulating genotypes. Epidemiological data and whole blood samples were collected from horses in the Distrito Federal. DNA was analyzed using qPCR for Theileria sp. and B. caballi, followed by cPCR for 18S rDNA ...
Asif S, Gulzar MW.Endometritis is a significant cause of infertility in mare. Some infectious agents disrupt the endometrium's innate immune system, resulting in a prolonged systemic inflammatory response that circulates via the blood or cellular degeneration, which ultimately leads to endometritis from bacterial endotoxins. Numerous biological processes use various small, non-coding RNA molecules called MicroRNAs. MicroRNAs (miRNAs) regulate gene expression after transcription by blocking transcription and translation. This manuscript examines patho-morphological discoveries in equine endometritis, the express...
Guo W, Li Z, Mao W, Liu X, Yang Y, Yu J, Yang H, Gao R.Flunixin meglumine (FM) is commonly used in painful conditions in horses; however, it may contribute to equine gastric ulcer syndrome (EGUS). Some veterinarians combine omeprazole (OME) and FM to reduce EGUS risk. However, the efficacy and safety of this combination in Mongolian horses with chronic lameness remain unknown. Objective: To investigate the changes in lameness and EGUS scores in Mongolian horses through the comparison of three treatment strategies: FM, FM + OME and placebo treated control (CON) and to assess the effects of these treatments on gastric fluid pH, serum total prote...
Macías-Rioseco M, Ochoa J, Choi EA, Blanchard P, Moeller RB, Uzal FA. spp. can cause gastroenteritis, hepatitis, bacteremia, and abortions in domestic animals and humans. Some spp. are zoonotic. To our knowledge, hepatitis caused by has not been reported in horses. Here we present a case of acute necrosuppurative hepatitis caused by infection in a 3-y-old gelding, and we review the literature on infections in various animal species. The horse had a one-week history of weight loss and weakness before becoming recumbent and dying. Grossly, the liver had rounded edges and was mottled. There were ecchymoses on the gastric serosa, and a large amount of mucoid, p...
Vaccination is one of the most important measures for preventing infectious diseases. Vaccinations against tetanus and West-Nile-Virus are essential to protect the individual horse. These infections are not contagious and are not transmitted from animal to animal. By contrast, Equine Influenza and Equine-Herpes-Virus infections are highly contagious, transmissible diseases. In addition to protecting the vaccinated individual, vaccinating as many horses as possible aims at inducing a broad herd immunity, which interrupts infection chains and thus additionally protects the individual. Vaccinatio...
de Moura Alonso J, Apolonio EVP, Teng FS, Perandré PI, Amorim RL, Mazaro RD, Watanabe MJ, Alves ALG, Hussni CA.In horses, basal cell neoplasms are uncommon benign tumors with slow growth mostly reported in the skin and eyelid. Malignant presentation is even more uncommon. This report describes a basal cell carcinoma (BCC) in the periocular region of a 10-year-old donkey. The animal presented good body condition and a neoformation in the right eye, noted 3 months prior to hospital admission. At the ophthalmological examination, the mass was identified above and adhered to the cornea, measuring 3.0 × 2.5 × 1.5 cm. Cytology revealed a suspicion of a malignant epithelial neoplasm, characterized ...
Primo ALM, Assis DM, Santos VGS, de Melo LRB, da Nóbrega LD, Medeiros Dantas AF, Maciel TA.Cerebellar abiotrophy is a neurodegenerative disease that affects the Purkinje cells of the cerebellum, resulting in premature neuronal death. In horses, its occurrence has been reported mainly in the Arabian breed as a congenital mutation inherited in an autosomal recessive manner. The objective of this study was to describe the case of cerebellar abiotrophy in a Quarter Horse foal. An 8-day-old foal was treated after presenting signs of ataxia, hypermetria, difficulty maintaining a standing position, and decreased menace response. The foal was hospitalized for 26 days, received treatment wit...
van der Graaf L, Leigh W, Szmatoła T, Roberts K, Ryan S, Brown B, Van Buren S, Finno CJ, Petersen JL.Anhidrosis is defined as a decreased or absent ability to sweat in response to heat and exercise. In horses, this condition can increase the risk of life-threatening hyperthermia. A prior study has suggested that equine anhidrosis is associated with a missense variant (rs68643109) in the Potassium Voltage-Gated Channel Subfamily E Regulatory Subunit 4 (KCNE4) gene. This project aimed to validate this association in a population of well-phenotyped horses and to determine the allele frequency of this variant in publicly available whole-genome sequence data. Fifty horses within the University of ...
O'Kennedy MM, Reedy SE, Abolnik C, Khan A, Smith T, du Preez I, Olajide E, Daly J, Cullinane A, Chambers TM.Equine influenza (EI) is a highly contagious acute respiratory disease of wild and domesticated horses, donkeys, mules, and other Equidae. EI is caused by the Equine Influenza virus (EIV), is endemic in many countries and outbreaks still have a severe impact on the equine industry globally. Conventional EI vaccines are widely used, but a need exists for a platform that facilitates prompt manufacturing of a highly immunogenic, antigenically matched, updated vaccine product. Here we developed a plant-produced bivalent EI virus-like particle (VLP) vaccine candidate which lacks the viral genome an...
Jacob O, Hause B, Peters-Smith K, Adam EN, Page AE, Floyd C, Tucker C, Eertink LG, Wang D, Li F.Equine sarcoids are the most identified skin tumors of horses, which are highly associated with bovine papillomavirus infection. Sarcoids can impair the use of the horse and are difficult to treat, resulting in significant economic losses and a welfare concern. There is no vaccine available to protect global equines from sarcoids. We aimed to determine the safety and protective antibody response in horses immunized with a recombinant baculovirus vector vaccine expressing the L1 protein of bovine papillomavirus type 1 (BPV1). A group of 10 clinically healthy, sarcoid-free horses were immunized ...
Basso RM, Cerri FM, Possebon FS, Braga PRC, Casas MRT, Oliveira-Filho JP, Araújo Júnior JP, Ribeiro MG, Arroyo LG, Borges AS. spp. are important pathogens of foals, causing clinical enterocolitis and sepsis. We characterized the resistance, virulence, and stress response genes in isolates from foals with or without diarrhea. isolates ( = 23) recovered from fecal samples of 16 diarrheic and 7 non-diarrheic <1-y-old foals were subjected to whole-genome sequencing. The most common serovars detected in diarrheic foals were subsp. serovars Infantis and Minnesota. Multidrug resistance was observed in 9 of 23 isolates, with 8 of the 9 from diarrheic foals. All of the isolates contained at least 2 resistance genes, ...
Wright CA, Lawton K, Barnum S, Craig BW, Farwell BR, Blea J, McCook C, Pusterla N.This study aimed to determine if exercise increases the frequency of selected respiratory viruses/bacteria shedding in non-clinical horses using nose wipes. Nose wipes were taken pre- and post- exercise from 133 healthy horses of various ages and disciplines. Wipes were assayed for the presence of selected common (equine herpesvirus-1 (EHV), EHV-4, S. equi spp equi) and commensal (EHV-2, EHV-5, S. equi spp zooepidemicus) respiratory pathogens. The frequency of detection increased significantly (p < 0.05) in the post-exercise wipes for EHV-1, EHV-2, EHV-5, and S. zooepidemicus. EHV-4 and S. equ...
Simões BP, Cerri FM, Takahira RK, Borges AS, Oliveira-Filho JP, Amorim RM.Chlorfenapyr is a pesticide that interferes with mitochondrial function, leading to cell death and mortality. Although poisoning is primarily documented in humans and dogs, it can result in severe clinical signs, including sweating, respiratory distress, and neurological dysfunction. This report describes the clinical and laboratory findings of a horse with suspected accidental intoxication with chlorfenapyr. A 4-year-old Quarter Horse mare was referred to the veterinary hospital with signs of excessive sweating, hyperthermia, tachypnea, muscle fasciculation, and fearful facial expression. The...
Story MR, King M, Nout-Lomas YS, Barrett MF, Kawcak C, Frisbie D, McIlwraith CW, Haussler KK.To develop and define a model of acute neck pain in an equine cervical articular process joint (APJ) using recombinant equine IL-1β (reIL-1β). Unassigned: 12 horses in this experimental study received a randomly assigned, unilateral intra-articular injection of 50 ng (n = 6) or 100 ng (n = 6) of reIL-1β and saline (contralateral side as control) into the C5-to-C6 APJ. Blinded ultrasonographic, clinical, and biomechanical parameters were evaluated between 4 hours and 14 days. Unassigned: There was a significant increase in APJ effusion on ultrasonographic examination that peaked at 24 hours ...
Johnston TJ, Stewart AJ, Dryburgh EL, Bertin FR.Pituitary pars intermedia dysfunction (PPID) is diagnosed by measuring the ACTH concentrations. Due to the reported instability of ACTH, it is recommended to transfer centrifuged plasma into cryovials; however, in practice, cryovials are infrequently used, and serum (red-top) tubes are used instead. This study investigated whether this procedure affects ACTH concentrations and the diagnosis of PPID. Unassigned: This was a cohort study. Blood was collected into EDTA tubes from 9 horses with PPID and 7 controls. After centrifugation, plasma was either aliquoted into a cryovial or into a serum tu...
Facile V, Magliocca M, Dini FM, Imposimato I, Mariella J, Freccero F, Urbani L, Rinnovati R, Sel E, Gallina L, Castagnetti C, Galuppi R, Battilani M....Equine piroplasmosis is a tick-borne disease caused by and species. Despite its presence in Europe, no laboratory testing is required for animal movement, even though some countries remain free of this disease. Differentiating between species and genotypes is crucial to determine the most effective treatment, as dosage, active compounds, and duration vary. However, diagnosis is often challenging due to genetic variability and the limited sensitivity of molecular methods. The aims of this study were to compare the performances of different molecular diagnostic tests to identify the most effec...
Tretow M, Hain AM, Bienert-Zeit A.Equine odontoclastic tooth resorption and hypercementosis (EOTRH) is a widespread dental disease with an unknown aetiology, mainly affecting the incisors and canine teeth of senior horses. Being clinically asymptomatic in early stages but progressively destructive and painful in many cases highlights the need for improvements in early diagnosis of EOTRH. This study describes how clinical and radiological findings correlate with distinguishing EOTRH-specific symptoms from non-specific findings. Clinical and radiographic examinations of the rostral oral cavity were performed in 154 Icelandic hor...
Talib MT, Nasir A, Kashif M, Rahman A, Rehman AU, Akbar H, Nadeem A, Howe DK, Azam MN.The aim of this study was to determine the prevalence of anti-Neospora (N.) caninum and anti-N. hughesi antibodies in horses and to appraise the associated risk factors in the two central districts (Jhang and Toba Tek Singh) of Punjab Province, Pakistan. A total of 300 horse sera were analyzed for the presence of antibodies to Neospora spp. using a competitive ELISA. The overall prevalence of antibodies against Neospora species in horses was 25 % (75/300; 95 % CI 20.1-29.9). The prevalence of antibodies to N. caninum and N. hughesi species was 12.3 % (37/300; 95 % CI 8.6-16) and 19.3 % (5...
Valberg SJ.Although horses most commonly develop exertional rhabdomyolysis, there are numerous causes for nonexertional rhabdomyolysis (nonER) that pose a serious health threat to horses. Their etiologies can be broadly categorized as toxic, genetic, inflammatory/infectious, nutritional, and traumatic and a variety of diagnostic tests are available to discern among them. This study discusses causes of nonER as well as diagnostics and treatments that are specific to each etiology. General treatment of acute rhabdomyolysis is covered in detail in the study in this issue on sporadic and recurrent exertional...
Palmisano MG, Colmer SF, Saw YL, Xu X, Stefanovski D, Murphy L, Johnson AL.To determine the prevalence of vitamin E deficiency in horses at admission and at the time of discharge. The hypothesis was that vitamin E concentrations would decrease during hospitalization. Methods: A prospective cohort study was performed of client-owned horses admitted as patients or companions through the emergency service at a tertiary referral center. Exclusion criteria included vitamin E supplementation. Whole blood was collected into an additive-free tube at the time of admission for all horses and at discharge if the horse was hospitalized for a minimum of 5 days. Serum vitamin E co...
Firshman AM, Valberg SJ.Type 1 Polysaccharide Storage Myopathy (PSSM1) is an autosomal dominant glycogen storage disorder affecting more than 20 breeds of horses that can present with a variety of signs, including exertional rhabdomyolysis (ER). It is diagnosed by genetic testing or muscle biopsies containing muscle fibers with abnormal amylase-resistant polysaccharide. Type 2 PSSM has recently been subdivided. PSSM2-ER is a glycogen storage disorder identified in Quarter Horses that causes ER and is diagnosed by muscle biopsy as its genetic basis is unknown. Both PSSM1 and PSSM2-ER respond well to a low nonstructura...
McKenzie E.The equine muscle system is complex and prone to a large range of hereditary and acquired diseases that often have overlapping clinical signs with orthopedic, neurologic, and other disorders. Obtaining a clinical history that fully outlines the client concerns and any known information about the disorder and following with a comprehensive physical examination and screening clinical pathology tests are fundamental to achieve definitive diagnosis. A methodical and comprehensive approach aids accurate diagnosis and development of an optimal treatment and management plan. This article describes th...
Poulet H, Minke J, Pardo MC, Juillard V, Nordgren B, Audonnet JC.The canarypox vaccine vector (ALVAC) technology has been used to develop and license several vaccines for companion animals and horses in the European Union and USA. ALVAC is a ubiquitous vector with high biosafety since it is non-replicative in mammalians, is genetically and physically stable, and able to induce both humoral and cell-mediated immune responses against the expressed transgene product. Specific rules apply for the development and registration of recombinant vector vaccines. The biology of the vector as well as the recombinant virus must be thoroughly documented to allow the risk...
Radtke CL, Nino-Fong R, Esparza Gonzalez BP, Stryhn H, McD￮ LA.To characterize equine muscle tissue- and periosteal tissue-derived cells as mesenchymal stem cells (MSCs) and assess their proliferation capacity and osteogenic potential in comparison with bone marrow- and adipose tissue-derived MSCs. Methods: Tissues from 10 equine cadavers. Methods: Cells were isolated from left semitendinosus muscle tissue, periosteal tissue from the distomedial aspect of the right tibia, bone marrow aspirates from the fourth and fifth sternebrae, and adipose tissue from the left subcutaneous region. Mesenchymal stem cells were characterized on the basis of morphology, ad...
Riggs CM, Vaughan LC, Evans GP, Lanyon LE, Boyde A.Mechanical test specimens were prepared from the cranial and caudal cortices of radii from eight horses. These were subjected to destructive tests in either tension or compression. The ultimate stress, elastic modulus and energy absorbed to failure were calculated in either mode of loading. Analysis was performed on the specimens following mechanical testing to determine their density, mineral content, mineral density distribution and histological type. A novel technique was applied to sections from each specimen to quantify the predominant collagen fibre orientation of the bone near the plane...
Tomlinson JE, Kapoor A, Kumar A, Tennant BC, Laverack MA, Beard L, Delph K, Davis E, Schott Ii H, Lascola K, Holbrook TC, Johnson P, Taylor SD....Three flaviviruses (equine pegivirus [EPgV]; Theiler's disease-associated virus [TDAV]; non-primate hepacivirus [NPHV]) and equine parvovirus (EqPV-H) are present in equine blood products; the TDAV, NPHV, and EqPV-H have been suggested as potential causes of serum hepatitis. Objective: To determine the prevalence of these viruses in horses with equine serum hepatitis. Methods: Eighteen horses diagnosed with serum hepatitis, enrolled from US referral hospitals. Methods: In the prospective case study, liver, serum, or both samples were tested for EPgV, TDAV, NPHV, and EqPV-H by PCR. Results: Bot...
Martins LC, Silva EVPD, Casseb LMN, Silva SPD, Cruz ACR, Pantoja JAS, Medeiros DBA, Martins Filho AJ, Cruz EDRMD, Araújo MTF, Cardoso JF....Serological evidence of West Nile virus (WNV) infection has been reported in different regions of Brazil from equine and human hosts but the virus had never been isolated in the country. Objective: We sought to identify the viral etiology of equine encephalitis in Espírito Santo state. Methods: We performed viral culture in C6/36 cells, molecular detection of WNV genome, histopathology and immunohistochemistry from horse cerebral tissue. We also carried out sequencing, phylogenetic analysis and molecular clock. Results: Histopathologic analysis from horse cerebral tissue showed injury related...
Weaver SC, Pfeffer M, Marriott K, Kang W, Kinney RM.Epizootics of Venezuelan equine encephalitis (VEE) involving subtype IAB viruses occurred sporadically in South, Central and North America from 1938 to 1973. Incompletely inactivated vaccines have long been suspected as a source of the later epizootics. We tested this hypothesis by sequencing the PE2 glycoprotein precursor (1,677 nucleotides) or 26S/nonstructural protein 4 (nsP4) genome regions (4,490 nucleotides) for isolates representing most major outbreaks. Two distinct IAB genotypes were identified: 1) 1940s Peruvian strains and 2) 1938-1973 isolates from South, Central, and North America...
Turner TA.Thermography is a practical aid in the clinical evaluation of the equine patient. It is particularly germane to the evaluation of lameness. This modality specifically increases the accuracy of diagnosis. Thermography is the pictorial representation of skin temperature. The technique involves the detection of infrared radiation, which can be directly correlated to blood flow. To be accurate, thermography must be performed in a controlled area free of drafts. The area should be protected from sunlight to avoid erroneous heating of the skin, and the horse's hair length should be uniform. Thermogr...
Theoret CL, Wilmink JM.Impaired wound healing represents an enormous clinical and financial problem for companion animals and humans alike. Unfortunately, most models used to study healing rely on rodents, which have significant differences in the healing and scarring process and rarely develop complications. In order to better simulate impaired healing, the model should strive to reproduce the natural processes of healing and delayed healing. Wounds on the limbs of horses display similarities to wounds in humans in their epithelialization/contraction ratio, genetic influence as well as dysregulated cytokine profile...
Richardson DW, Dodge GR.To determine the effects of interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) on expression and regulation of several matrix-related genes by equine articular chondrocytes. Methods: Articular cartilage harvested from grossly normal joints of 8 foals, 6 yearling horses, and 8 adult horses. Methods: Chondrocytes maintained in suspension cultures were treated with various doses of human recombinant IL-1beta or TNF-alpha. Northern blots of total RNA from untreated and treated chondrocytes were probed with equine complementary DNA (cDNA) probes for cartilage matrix-related ge...
McPartlin LA, Suarez SS, Czaya CA, Hinrichs K, Bedford-Guaus SJ.Capacitation is a complex and not well-understood process that encompasses all the molecular changes sperm must undergo to successfully fertilize an oocyte. In vitro fertilization has remained elusive in the horse, as evidenced by low in vitro fertilization (IVF) rates (0%-33%); moreover, only two foals have ever been produced using IVF. Incubation of stallion sperm in modified Whittens supplemented with bovine serum albumin and sodium bicarbonate yielded significant rates of time-dependent protein tyrosine phosphorylation and induced acrosomal exocytosis, consistent with capacitation. The obj...
Leemans B, Gadella BM, Stout TA, De Schauwer C, Nelis H, Hoogewijs M, Van Soom A.In contrast to man and many other mammalian species, conventional in vitro fertilization (IVF) with horse gametes is not reliably successful. The apparent inability of stallion spermatozoa to penetrate the zona pellucida in vitro is most likely due to incomplete activation of spermatozoa (capacitation) because of inadequate capacitating or fertilizing media. In vivo, the oviduct and its secretions provide a microenvironment that does reliably support and regulate interaction between the gametes. This review focuses on equine sperm-oviduct interaction. Equine sperm-oviduct binding appears to be...
Rudolph J, O'Callaghan DJ, Osterrieder N.The genome of equine herpesvirus type 1 (EHV-1) strain RacL11, a highly virulent isolate obtained from an aborted foal, and that of the modified live vaccine strain KyA, were cloned as bacterial artificial chromosomes (BAC) in Eseherichia coli. Mini F plasmid sequences were inserted into the viral genomes by homologous recombination instead of the gene 71 (EUS4) open reading frame after co-transfection of viral DNA and recombinant plasmid pdelta71-pHA2 into RK13 cells. After isolation of recombinant viruses by three rounds of plaque purification, viral DNA was isolated from RK13 cells infected...
Ball JM, Rushlow KE, Issel CJ, Montelaro RC.We describe here a detailed analysis of the antigenic determinants of the surface unit glycoprotein (gp90) of equine infectious anemia virus (EIAV), using a comprehensive panel of synthetic peptides in enzyme-linked immunosorbent assays with immune serum from naturally and experimentally infected horses and with a panel of gp90-specific neutralizing and nonneutralizing monoclonal antibodies. The results of these studies identify immunoreactive segments throughout the conserved and variable domains of gp90 but localize immunodominant (100% reactivity) determinants to the amino and carboxyl term...
Perkins GA, Lamb S, Erb HN, Schanbacher B, Nydam DV, Divers TJ.Plasma ACTH levels have been variable in horses with a positive clinical response for therapy for equine Cushing's Disease (ECD). Therefore, our purpose was to determine the value of monitoring plasma adrenocorticotropin (ACTH) levels during treatment of equine Cushing's disease (ECD) with either cyproheptadine (n = 32) or pergolide (n = 10). First, we validated the chemiluminescent ACTH assay (specificity, precision, accuracy, intra-assay and interassay variations) and tested methods of handling the whole blood from the time of collection to when the ACTH was assayed. The sensitivity and spec...
Haber M, Cao Z, Panjwani N, Bedenice D, Li WW, Provost PJ.The physiologic mechanisms involving growth factors, including PDGF-BB, EGF, and TGF-beta 1, as potent mediators of fibroblasts and epithelial cells in corneal wound healing remain unknown. The goal of this study was to determine culture methods for equine epithelial cells and keratocytes and to investigate how exogenous growth factors influence proliferation of both cell types. Methods: Cell cultures were established from healthy corneas harvested from horses immediately following euthanasia and maintained using standard tissue culture protocols. To determine the effects of PDGF-BB, EGF, TGF-...
Tomlinson JE, Tennant BC, Struzyna A, Mrad D, Browne N, Whelchel D, Johnson PJ, Jamieson C, Löhr CV, Bildfell R, McKenzie EC, Laverack M, Renshaw RW....A novel equine parvovirus (EqPV-H) was recently discovered in the equine liver with Theiler's disease. Objective: To determine the prevalence of EqPV-H infection in naturally occurring Theiler's disease cases and in-contact horses in the absence of historical equine biologic product administration. Methods: Ten cases of Theiler's disease from 6 separate properties were included in the study, based on the criteria of acute onset of clinical signs of liver failure with laboratory or histopathologic findings characteristic of Theiler's disease and no history of receiving an equine biologic produc...
Saito S, Ugai H, Sawai K, Yamamoto Y, Minamihashi A, Kurosaka K, Kobayashi Y, Murata T, Obata Y, Yokoyama K.Embryonic stem (ES) cells are pluripotent cells with the potential capacity to generate any type of cell. We describe here the isolation of pluripotent ES-like cells from equine blastocysts that have been frozen and thawed. Our two lines of ES-like cells (E-1 and E-2) appear to maintain a normal diploid karyotype indefinitely in culture in vitro and to express markers that are characteristic of ES cells from mice, namely, alkaline phosphatase, stage-specific embryonic antigen-1, STAT-3 and Oct 4. After culture of equine ES-like cells in vitro for more than 17 passages, some ES-like cells diffe...
Cuny C, Witte W.MRSA infections in equine clinics were reported from Northern America, Europe, Australia, and Japan. The majority of nosocomial infections in horses is obviously associated with particular MRSA clonal lineages. As already observed for epidemic MRSA in human hospitals more than 10 years ago, a dynamics of MRSA clonal lineages is also observed in European equine clinics: clonal lineages belonging to clonal complex (CC) 8 are on the retreat whereas MRSA attributed to CC398 become increasingly prevalent. The majority of CC398 isolates belong to a subpopulation which is particularly associated with...
Nemoto M, Oue Y, Morita Y, Kanno T, Kinoshita Y, Niwa H, Ueno T, Katayama Y, Bannai H, Tsujimura K, Yamanaka T, Kondo T.Recently, outbreaks associated with equine coronavirus (ECoV) have occurred in Japan and the United States. While ECoV is likely to be pathogenic to horses, it has not been shown that experimental inoculation of horses with ECoV produces clinical signs of disease. In this study, we inoculated three Japanese draft horses with an ECoV-positive diarrheic fecal sample to confirm infection after inoculation and to investigate the clinical course and virus shedding patterns of ECoV. Virus neutralization tests showed that all three horses became infected with ECoV. Two of the three horses developed c...
Nielsen MK, Peterson DS, Monrad J, Thamsborg SM, Olsen SN, Kaplan RM.Strongylus vulgaris is an important strongyle nematode with high pathogenic potential infecting horses world-wide. Several decades of intensive anthelmintic use has virtually eliminated clinical disease caused by S. vulgaris, but has also caused high levels of anthelmintic resistance in equine small strongyle (cyathostomin) nematodes. Recommendations aimed at limiting the development of anthelmintic resistance by reducing treatment intensity raises a simultaneous demand for reliable and accurate diagnostic tools for detecting important parasitic pathogens. Presently, the only means available t...
Reesink HL, Watts AE, Mohammed HO, Jay GD, Nixon AJ.The goals of this study were (1) to quantify proteoglycan 4 (PRG4) gene expression; (2) to assess lubricin immunostaining; and (3) to measure synovial fluid lubricin concentrations in clinical and experimental models of equine carpal osteoarthritis (OA). Lubricin synovial fluid concentrations and cartilage and synovial membrane PRG4 expression were analyzed in research horses undergoing experimental OA induction (n = 8) and in equine clinical patients with carpal OA (n = 58). Lubricin concentrations were measured using a custom sandwich enzyme-linked immunosorbent assay, and PRG4 expressio...
Roche SE, Wicks R, Garner MG, East IJ, Paskin R, Moloney BJ, Carr M, Kirkland P.To provide an overview and descriptive analysis of the 2011 arboviral disease epidemic in horses that involved three important Australian mosquito-borne viruses: Murray Valley encephalitis virus, West Nile virus (Kunjin strain) and Ross River virus. Methods: Data from states affected between January and June 2011 were collated and comprised reports of horses showing signs of neuromuscular disease and the associated laboratory findings. A summary of the data is presented, together with a spatiotemporal analysis of cases and preliminary assessment of rainfall patterns and case distribution. Resu...
Bullone M, Lavoie JP.Human asthma is a complex and heterogeneous disorder characterized by chronic inflammation, bronchospasm and airway remodeling. The latter is a major determinant of the structure-function relationship of the respiratory system and likely contributes to the progressive and accelerated decline in lung function observed in patients over time. Corticosteroids are the cornerstone of asthma treatment. While their action on inflammation and lung function is well characterized, their effect on remodeling remains largely unknown. An important hindrance to the study of airway remodeling as a major focu...
Zhao Y, Holden VR, Smith RH, O'Callaghan DJ.The UL3 protein of equine herpesvirus 1 (EHV-1) KyA strain is a homolog of the ICP27 alpha regulatory protein of herpes simplex virus type 1 (HSV-1) and the ORF 4 protein of varicella-zoster virus. To characterize the regulatory function of the UL3 gene product, a UL3 gene expression vector (pSVUL3) and a vector expressing a truncated version of the UL3 gene (pSVUL3P) were generated. These effector plasmids, in combination with an EHV-1 immediate-early (IE) gene expression vector (pSVIE) and chimeric EHV-1 promoter-chloramphenicol acetyltransferase (CAT) reporter constructs, were used in trans...
Thorpe CT, Karunaseelan KJ, Ng Chieng Hin J, Riley GP, Birch HL, Clegg PD, Screen HR.Although the predominant function of all tendons is to transfer force from muscle to bone and position the limbs, some tendons additionally function as energy stores, reducing the energetic cost of locomotion. To maximise energy storage and return, energy-storing tendons need to be more extensible and elastic than tendons with a purely positional function. These properties are conferred in part by a specialisation of a specific compartment of the tendon, the interfascicular matrix, which enables sliding and recoil between adjacent fascicles. However, the composition of the interfascicular matr...
Equine trypanosomosis is a complex of infectious diseases called dourine, nagana and surra. It is caused by several species of the genus Trypanosoma that are transmitted cyclically by tsetse flies, mechanically by other haematophagous flies, or sexually. Trypanosoma congolense (subgenus Nannomonas) and T. vivax (subgenus Dutonella) are genetically and morphologically distinct from T. brucei, T. equiperdum and T. evansi (subgenus Trypanozoon). It remains controversial whether the three latter taxa should be considered distinct species. Recent outbreaks of surra and dourine in Europe illustrate ...
Stewart HL, Southwood LL, Indugu N, Vecchiarelli B, Engiles JB, Pitta D.The faecal microbiota is emerging as potentially important in intestinal disease. More research is needed to characterise the faecal microbiota from horses with colic. Objective: To compare the relative abundance of bacterial populations comprising the faecal microbiota in horses presenting for colic compared with an elective surgical procedure. Methods: Prospective observational clinical study. Methods: Admission faecal samples were collected from horses presenting for colic and elective surgical procedures. Faecal samples were extracted for genomic DNA, PCR- amplified, sequenced and analysed...
Nielsen MK, Vidyashankar AN, Andersen UV, Delisi K, Pilegaard K, Kaplan RM.Fecal analyses are becoming increasingly important for equine establishments as a means of parasite surveillance and detection of anthelmintic resistance. Although several studies have evaluated various egg counting techniques, little is known about the quantitative effects of pre-analytic factors such as collection and storage of fecal samples. This study evaluated the effects of storage temperature, storage time and airtight versus open-air storage on fecal egg counts. The experimental protocols were replicated in two study locations: Copenhagen, Denmark and Athens, Georgia, USA. In both loc...
Nielsen MK, Vidyashankar AN, Olsen SN, Monrad J, Thamsborg SM.Nematodes belonging to the order Strongylida are ubiquitous in grazing horses, and the large strongyle Strongylus vulgaris is considered the most pathogenic. This parasite was originally described widely prevalent in equine establishments, but decades of frequent anthelmintic treatment appears to have reduced the prevalence dramatically. Increasing levels of anthelmintic resistance in cyathostomin parasites have led to implementation of selective therapy to reduce further development of resistance. It has been hypothesized that S. vulgaris could reoccur under these less intensive treatment cir...
Perkins GA, den Bakker HC, Burton AJ, Erb HN, McDonough SP, McDonough PL, Parker J, Rosenthal RL, Wiedmann M, Dowd SE, Simpson KW.Little is known about the gastric mucosal microbiota in healthy horses, and its role in gastric disease has not been critically examined. The present study used a combination of 16S rRNA bacterial tag-encoded pyrosequencing (bTEFAP) and fluorescence in situ hybridization (FISH) to characterize the composition and spatial distribution of selected gastric mucosal microbiota of healthy horses. Biopsy specimens of the squamous, glandular, antral, and any ulcerated mucosa were obtained from 6 healthy horses by gastroscopy and from 3 horses immediately postmortem. Pyrosequencing was performed on bio...
