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.
Herschel TL, Pelli A, Winter K, Scharner D.Penetrating wounds of the hoof are common and potentially life-threatening injuries in equine veterinary practice. The aim of this study was the systematic data analysis of horses presenting to the clinic with a solar puncture wound.In this retrospective study, patient data from horses presented with a puncture wound to the hoof in the period from September 2008 to August 2024 were collected. The analyzed data covered signalment, intended use, and insurance status. The following were also considered: previous history including the period between injury and presentation to the clinic, affected ...
Sakai DM, Ishikawa Y, Im JSY, Zhang S, Reed RA, Quandt JE, Barletta M, Knych HK.Administering large volumes of bupivacaine in the rectus abdominis sheath (RAS) block in horses could cause local anesthetic toxicity. This study aimed to evaluate the pharmacokinetics of 2 mg/kg bupivacaine in RAS blocks and the associated toxicity risk. Six healthy adult horses were sedated with xylazine and received an ultrasound-guided bilateral 2-point RAS block. Plasma samples were collected at baseline and from 5 min to 24 h after the block and analyzed using liquid chromatography-tandem mass spectrometry. A noncompartmental analysis was performed to determine the maximum concentr...
Vandaele Z, Flyps J, Cuypers C, De Baere S, Devreese M, Schauvliege S.Subanaesthetic doses of ketamine (0.5 mg kg) provide analgesia in several species, but there is limited information on the pharmacokinetics and clinical effects of intramuscularly administered ketamine in horses. This study investigated the pharmacokinetics of ketamine and norketamine, and evaluated clinical effects, ataxia, and vital parameters, following intramuscular and intravenous administration of 0.5 mg kg ketamine in nine healthy horses, using a randomized two-period crossover design with a 1-week washout period. Plasma concentrations were analyzed using Ultra-High Performance ...
Yoshitomi MD, Kuramoto T, Hatazoe T, Mitsuda K, Smith H, Misumi K.Culture protocols need to yield 100 million equine synovial fluid (SF)-derived mesenchymal stromal cells (SF-MSCs) in around 3 weeks are needed, before these cells can be evaluated as agents of articular repair in clinical trials. Objective: To investigate mass culture of equine SF-MSC culture protocols using nonwoven polyethylene terephthalate (PET) fabrics for the potential to meet the targets for clinical trials. Methods: In vitro experiments. Methods: SF samples were collected from the carpal joints in thoroughbred racehorses (n = 21) undergoing arthroscopic surgery and cultured in 10%...
Rodrigues GJ, Monteiro FDO, Teixeira PPM.This case report describes the successful application of video-assisted hysteroscopy to evaluate endometrial recovery in a 6-year-old mare following treatment for complete uterine prolapse secondary to dystocia. Upon presentation, the uterus was manually reduced and supported with a Buhner's suture. A multimodal medical protocol, including broad-spectrum antibiotics, anti-inflammatory drugs and uterine lavage, was initiated. Five days after reduction, an endoscopic evaluation was performed using a dedicated videovaginoscope without uterine insufflation. The procedure provided high-resolution i...
Firdausy LW, Fikri F, Wicaksono AP, Maslamama ST, Purnama MTE.Equine viral arteritis (EVA) is a globally widespread infectious disease affecting equids, with significant consequences for reproductive efficiency and the regulation of international equine trade. Nevertheless, despite the accumulation of numerous region-specific investigations, an integrated synthesis of global seroprevalence estimates and overarching epidemiological patterns remains insufficiently developed. Objective: To calculate the pooled global seroprevalence of EVA and to explore sources of epidemiological heterogeneity. Methods: A systematic review and meta-analysis were undertaken ...
Dos Santos Pinto M, Angeluci GC, Neto JABC, Dos Santos Barbosa I, da Silva Tito RK, Lima SG, Braga VG, Lima VMF, Lucheis SB, Sabioni MS, Kawai JGC....In this research, a seroepidemiological survey was conducted on 202 horses located on 21 properties in the northwestern region of the state of São Paulo (Brazil) to estimate exposure to Leishmania spp., Toxoplasma gondii, and Trypanosoma cruzi. Antibodies against Leishmania, T. gondii and T. cruzi, were detected in 48 (23.76%), 29 (14.36%) and 2 (0.99%) of the 202 horses, respectively. We found a significantly higher occurrence of antibodies against Leishmania compared to those against the other protozoa (Chi-Square = 46.7, 2 d.f., P < 0.001). Seropositivity for the aforementioned prot...
Alvarado Soto GJ, Maldonado M, Armentrout A, Woolard K, Aleman M, Giaretta P, Willis AT.Achalasia is the most common motility disorder of the esophagus in humans and has been diagnosed in cats and dogs. We describe a 4-month-old Quarter Horse colt with failure to thrive, recurrent colic episodes, and aspiration pneumonia, in which fluoroscopic evaluation identified a caudal esophageal motility disorder consistent with achalasia. Necropsy examination confirmed achalasia.
Pinnell E, Shoemaker S, Wang Y, Tang Y, Sellon D, Leguillette R, Gold J, Sanz M, Bayly WM.Environmental risk factors could contribute to the development of exercise-induced pulmonary hemorrhage (EIPH) in racing Thoroughbreds. Objective: To identify environmental risk factors that might contribute to differences in EIPH prevalence and severity across 12 Thoroughbred racetracks in the United States. Methods: Eight hundred fifteen 2-year-old and 122 >2-year-old Thoroughbred racehorses. Methods: Prospective blinded observational study. Videoendoscopy was performed 30-60 min post-race. Three observers independently assigned an EIPH grade to each videorecording, and prevalence and sever...
Kapadia CL, Crook RA, Coleman S, Unger G, Douglas RH, Fedorka CE.Altrenogest is commonly used in equine veterinary medicine for the control of estrus, behavioral modifications, and maintenance of pregnancy. Recent studies have found that altrenogest may impact aspects of the immune system, including altering cytokine production in circulation and within the reproductive tract. Therefore, we hypothesize that this alteration may lead to a deviated immune response to vaccination. Sixteen mares were divided into two groups, with ten mares (n = 10) receiving long-acting injectable altrenogest (100 mg/mL; IM) administered every 10 days, and six mares (n =...
Fukumoto N, Shibata M, Hayashi M, Kawauchi K, Yabuuchi Y, Oue Y, Matsuyama R, Yamamoto T, Mita H, Kawanishi N, Bannai H, Tsujimura K, Yamanaka T....In 2025, an outbreak of equine influenza occurred among draft horses at Obihiro Racecourse in Hokkaido, Japan. The number of horses showing clinical signs increased dramatically in April. The proportion affected was significantly higher in 2-year-olds than in older groups. The proportion that developed fever during the outbreak was significantly higher than that observed among Thoroughbreds during the 2007 outbreak. In non-epidemic periods, the geometric mean hemagglutination inhibition antibody titer of 2-year-old draft horses was significantly lower than that of 2-year-old Thoroughbreds. The...
Aguirre Siliezar K, Datu C, Proia K, Rotstein D, Nemser SM, Tyson GH, Ragsdale JM, Wilkes RP, Baker RE, Carossino M, Del Piero F, Sasaki E, Yant P....A multi-state outbreak of equine botulism occurred between December 2022 and March 2023 in the United States. Follow-up and testing were performed on 42 horses, including 24 that died or were euthanized in the outbreak that affected ~98 horses. Affected horses had all been exposed to the same commercial feed. Clinical signs included progressive muscle weakness and tremors, recumbency, and colic. No significant gross or microscopic abnormalities were observed on autopsy. Feces and gastrointestinal content were tested for various infectious agents, including botulinum toxin; fecal samples from 2...
Shams N, Jaydari A, Khademi P, Eydi J, Sgroi G.Due to the abundance of ticks on open grassy surfaces, racetracks may represent ideal scenarios for tick-borne pathogens. Therefore, in 2024/2025 Turkmen horses (Akhal-Teke breed) and ticks collected by dragging in paddocks of Iran were screened for Anaplasmataceae using Sanger sequencing on 16S rRNA, TRP36 and dsb genes. Amongst 200 horses, 11 (5.5%) tested positive without signs/symptoms, being 8 (4%) for Ehrlichia canis and 3 (1.5%) for Anaplasma ovis; no difference in prevalence was found by gender and age (p>0.05). All ticks were identified as Hyalomma asiaticum and Haemaphysalis sulca...
Hagenbach M, Bierau J, Rott P, Röcken M, Staszyk C.The aim of this study was to display clinically relevant anatomical structures of the carpal region in healthy horses with the help of cone beam computed tomography (CBCT).Twenty-eight forelimbs from 15 adult horses without orthopedic diseases were examined. Following native CBCT examination a mixture of hyperattenuating contrast medium with blue epoxy resin dye was injected in the antebrachiocarpal joint and middle carpal joint and contrast-enhanced CBCT scans were also acquired. Subsequently, the limbs were frozen and sawed in different planes corresponding to selected CBCT planes (dorsal, s...
Patterson HE, Yocom AF, Seabaugh KA, Kawcak CE, Contino EK.Recent evidence has shown that perineural analgesia may be less specific than previously thought. Objective: To compare the effects of four distal limb perineural analgesia techniques on resolving synovitis-induced lameness of the equine metacarpophalangeal joint (MCPJ). Methods: Nine horses had one MCPJ injected with 75ng of recombinant equine interleukin-1β (reIL-1β). Ten hours later, horses underwent one of two blocking patterns: (1) a palmar digital (PDNB) followed by an abaxial sesamoidean (ASNB) nerve block or (2) a palmar metacarpal (PMNB) followed by a palmar (PaNB) nerve block. Skin...
Palunas V, Fussell D, Helgert N, Long AE, Aitken MR, Abraham M.A 2-year-old Irish Sport Horse colt presented with acute, severe and rapidly progressive neurological signs, arriving recumbent to the hospital. Ante-mortem diagnostics did not reveal the cause of the recumbency, and the colt was euthanized after treatment and supportive care did not result in clinical improvement. A cranial cervical extradural mast cell tumour with eosinophilic granulomas and secondary compressive myelopathy with axonal degeneration was diagnosed on post-mortem evaluation. No other masses or clinically relevant findings were present, suggesting a primary neoplasm. Neoplasia a...
Al Aiyan A, Alnahdi AF, Abu Hayah S, Alshamsi A, Alshebli H, Aleissaee S, Balan R.The cerebral blood supply in horses is maintained by carotid and vertebrobasilar systems, which join the cerebral arterial circle to ensure continuous brain perfusion. This study aimed to comprehensively describe the origins, courses, and interconnections of the vertebrobasilar and carotid systems in the horse brain. Unassigned: Ten adult equine specimens were obtained from horses euthanized for non-neurological reasons. Following perfusion with 10% formaldehyde, colored latex was injected into the arterial system, and detailed dissections were performed to study major intracranial vessels. Un...
O'Brien K, Mair T, Mudhar HS, Pesavento P, Miller H, Priestnall SL, Suárez-Bonnet A.Equine squamous cell carcinomas (eSCCs) are common, and a proportion are likely induced by papillomavirus 2 (EcPV-2). Accurate prediction of clinical outcomes is challenging with no recognized prognostic criteria or consistent histopathological classification scheme for eSCC. The aims of this study were to histopathologically subtype a large case series of eSCCs (genital and ocular) and correlate them with p16 and HER-2 expression, equine papillomavirus infection status, and various clinical and histopathological parameters to predict tumour behavior and prognosis. One hundred and eighty-five...
van Erck-Westergren E, O'Connor S, Stewart BD, Dubois G, Morton J, Hinchcliff KW, Ter Woort F.The frequency, characteristics, and relationship with performance of arrhythmias occurring during high-intensity exercise in Thoroughbred racehorses remain poorly understood. Objective: Describe the frequency, characteristics, and association with subsequent race performance of arrhythmias occurring during intense exercise. Methods: Seventy-one racehorses competing in races sanctioned by the Hong Kong Jockey Club. Methods: Risk-based case-control study. Single-lead ECGs were recorded during high-intensity trials using wearable devices. Ectopic depolarizations identified during warm-up, maximal...
Pye E, Marcilla MG, Duncan JC.Regional anaesthesia of the equine anogenital tract is limited to local infiltration, extradural, blind palpation and nerve stimulator-guided techniques which risk iatrogenic damage, recumbency and ataxia. This study aimed to describe and assess the feasibility of transcutaneous ultrasound-guided (USG) pudendal nerve staining in equine cadavers. An initial pilot phase used two fresh equine cadavers and one standing unsedated horse to image the intrapelvic anatomy using ultrasound. One fixed equine cadaver specimen was also dissected to identify the pudendal nerve and refine the dissection appr...
Benetti E, Tambella AM, Andreis SN, Witte S, Di Bella C, Spadavecchia C.Osteoarthritis (OA) is a prevalent cause of chronic pain and lameness in horses. Whereas lameness can be quantified using objective measures, the assessment of OA-associated pain remains challenging. This study aimed to evaluate the applicability of the Client-Specific Outcome Measure (CSOM), a tool widely used in small animals, for the assessment of chronic OA pain in horses through caretaker evaluation. Unassigned: Seventeen privately owned horses with confirmed OA were enrolled in a 20-week randomized, double-blind, placebo-controlled study. For each horse, three individual pain-related ind...
Rocha IAB, Araujo F, Rosa LP.Friesian horses are recognized for severe genetic restriction due to intensive selection. Still, the genetic diversity, founder representation, and prevalence of inherited disorders in the Brazilian Friesian population, which is comprised of fewer than 500 individuals, have not been previously investigated AIMS/OBJECTIVES: characterize the genetic diversity, inbreeding, founder representation using pedigree-based tools, and frequency of known pathogenic, behavioral, and white spotting alleles in Friesian horses registered in Brazil METHODS: Pedigree data from 411 Friesian horses (2003-2024) we...
Mochal-King C, Strunk R, Paul L.Resveratrol is a compound found in multiple plants and there is evidence for its use as a supplement in horses, particularly through protection of chondrocytes. Previous studies on the clinical efficacy of resveratrol supplementation in horses have reported limited benefits. To date, there is no pharmacokinetic data of resveratrol in horses but the bioavailability of resveratrol in other species is poor. In this crossover study, the plasma concentrations of two forms of resveratrol were examined. Each horse received via nasogastric tube, either a single dose of resveratrol phospholipid or a st...
Souza MG, Mota Melo L, Martinez RE, Teague SR, Beck RL.In vitro fertilization (IVF) in horses has emerged as a valuable assisted reproductive technology, yet the impact of embryo cryopreservation on pregnancy outcomes when utilizing this technique remains unclear. This study reports pregnancy outcomes following transfer of conventional equine IVF embryos, with both fresh and vitrified-warmed embryos. Conventional IVF (cIVF) was used to produce 40 embryos, which were transferred to recipient mares, pregnancy diagnosis was performed at 6 days post-transfer followed by embryonic heartbeat detection between day 25 and 30 of gestation. Observed pregnan...
Pigé C, Vaughan B, Reesink HL.To describe principles of ultrasound-guided injection techniques for intralesional delivery of regenerative orthobiologics into equine tendon and ligament core lesions. Unassigned: A university-owned horse and equine cadaver forelimbs. Unassigned: A reproducible protocol for ultrasound-guided injection is demonstrated with the superficial digital flexor tendon used as an example. Following diagnosis of the lesion, the horse should be sedated and the affected limb desensitized with perineural anesthesia. The lesion is identified ultrasonographically in transverse and longitudinal planes, marked...
Błaszczak A, Olczak K, Stefaniuk-Szmukier M, Tomczyk-Wrona I, Musiał AD, Grzegorczyk J, Długosz B, Szmatoła T, Ropka-Molik K.Insect bite hypersensitivity (IBH) is a prevalent allergic skin disease in horses that significantly affects animal welfare and shows evidence of genetic predisposition. Objective: Understanding the genetic basis of IBH can improve management and breeding strategies. The Equine80K BeadChip microarray was used to identify genomic regions associated with the occurrence of IBH in Hucul horses. Methods: Hair samples were collected from 127 Hucul horses, including both affected individuals and controls. DNA was extracted and genotyped. A genome-wide association study (GWAS) was performed to identif...
Scott D, Kreitner K, Kim L, Seabaugh K, Duncan C, Magzamen S.To characterize spatiotemporal patterns of criteria air pollutants surrounding Thoroughbred racetracks in the US. Unassigned: We identified all active Thoroughbred racetracks from 2011 through 2024, linking their location with daily air quality data from the US Environmental Protection Agency (EPA) Air Quality System. Mean daily and annual pollutant concentrations within a 50-km bounding box of each racetrack were summarized using descriptive statistics and evaluated for monthly and annual trends. Exceedances were defined as any observation in which pollutant concentration met or exceeded the ...
Carroll CL, Huntington PJ.Three hundred and seventy two horses of varying breeds, height and fatness were weighed and measured for height at the withers. They were assessed for condition score by adaptation of a previously published method. The heart girth and length of 281 of the horses were also measured. Weight of horses was highly correlated (P less than 0.001) with height (r2 = 0.62), condition score (r2 = 0.22) and girth2 x length (r2 = 0.90). Nomograms were constructed to predict weight from height and condition score, and girth and length measurements. Weight can also be accurately estimated from the formula: (...
Godwin EE, Young NJ, Dudhia J, Beamish IC, Smith RK.Mesenchymal stem (progenitor; stromal) cell (MSC) therapy has gained popularity for the treatment of equine tendon injuries but without reports of long-term follow-up. Objective: To evaluate the safety and reinjury rate of racehorses after intralesional MSC injection in a large study of naturally occurring superficial digital flexor tendinopathy and to compare these data with those published for other treatments. Methods: Safety was assessed clinically, ultrasonographically, scintigraphically and histologically in a cohort of treated cases: 141 client-owned treated racehorses followed-up for a...
Selvey LA, Wells RM, McCormack JG, Ansford AJ, Murray K, Rogers RJ, Lavercombe PS, Selleck P, Sheridan JW.To describe the clinical and epidemiological features of an outbreak of a viral infection affecting humans and horses. Methods: Stables in Hendra, a suburb of Brisbane. Methods: Affected horses and humans, and at-risk human contacts. Results: A pregnant mare died two days after arrival from a paddock elsewhere in Brisbane. Eight to 11 days later, illness (depression, anorexia, fever, dyspnoea, ataxia, tachycardia, tachypnoea and nasal discharge) was reported among 17 other horses from the same or an adjoining stable. Fourteen horses died or were put down. Five and six days after the index mare...
Ching PK, de los Reyes VC, Sucaldito MN, Tayag E, Columna-Vingno AB, Malbas FF, Bolo GC, Sejvar JJ, Eagles D, Playford G, Dueger E, Kaku Y....During 2014, henipavirus infection caused severe illness among humans and horses in southern Philippines; fatality rates among humans were high. Horse-to-human and human-to-human transmission occurred. The most likely source of horse infection was fruit bats. Ongoing surveillance is needed for rapid diagnosis, risk factor investigation, control measure implementation, and further virus characterization.
Pawelek KA, Huynh GT, Quinlivan M, Cullinane A, Rong L, Perelson AS.Influenza virus infection remains a public health problem worldwide. The mechanisms underlying viral control during an uncomplicated influenza virus infection are not fully understood. Here, we developed a mathematical model including both innate and adaptive immune responses to study the within-host dynamics of equine influenza virus infection in horses. By comparing modeling predictions with both interferon and viral kinetic data, we examined the relative roles of target cell availability, and innate and adaptive immune responses in controlling the virus. Our results show that the rapid and ...
Webb JG, Chandavimol M, Thompson CR, Ricci DR, Carere RG, Munt BI, Buller CE, Pasupati S, Lichtenstein S.Percutaneous aortic valve implantation by an antegrade transvenous approach has been described but is problematic. Retrograde prosthetic aortic valve implantation via the femoral artery has potential advantages. Percutaneous prosthetic aortic valve implantation via the femoral arterial approach is described and the initial experience reported. Results: The valve prosthesis is constructed from a stainless steel stent with an attached trileaflet equine pericardial valve and a fabric cuff. After routine aortic balloon valvuloplasty, a 22F or 24F sheath is advanced from the femoral artery to the a...
Desquesnes M, Holzmuller P, Lai DH, Dargantes A, Lun ZR, Jittaplapong S.Trypanosoma evansi, the agent of "surra," is a salivarian trypanosome, originating from Africa. It is thought to derive from Trypanosoma brucei by deletion of the maxicircle kinetoplastic DNA (genetic material required for cyclical development in tsetse flies). It is mostly mechanically transmitted by tabanids and stomoxes, initially to camels, in sub-Saharan area. The disease spread from North Africa towards the Middle East, Turkey, India, up to 53° North in Russia, across all South-East Asia, down to Indonesia and the Philippines, and it was also introduced by the conquistadores into Latin ...
Fortier LA, Potter HG, Rickey EJ, Schnabel LV, Foo LF, Chong LR, Stokol T, Cheetham J, Nixon AJ.The purpose of this study was to compare the outcomes of treatment with bone marrow aspirate concentrate, a simple, one-step, autogenous, and arthroscopically applicable method, with the outcomes of microfracture with regard to the repair of full-thickness cartilage defects in an equine model. Methods: Extensive (15-mm-diameter) full-thickness cartilage defects were created on the lateral trochlear ridge of the femur in twelve horses. Bone marrow was aspirated from the sternum and centrifuged to generate the bone marrow concentrate. The defects were treated with bone marrow concentrate and mic...
Puffer BA, Parent LJ, Wills JW, Montelaro RC.We have previously demonstrated that the Gag p9 protein of equine infectious anemia virus (EIAV) is functionally homologous with Rous sarcoma virus (RSV) p2b and human immunodeficiency virus type 1 (HIV-1) p6 in providing a critical late assembly function in RSV Gag-mediated budding from transfected COS-1 cells (L. J. Parent et al., J. Virol. 69:5455-5460, 1995). In light of the absence of amino acid sequence homology between EIAV p9 and the functional homologs of RSV and HIV-1, we have now designed an EIAV Gag-mediated budding assay to define the late assembly (L) domain peptide sequences con...
Woldehiwet Z.Anaplasma phagocytophilum is the recently designated name replacing three species of granulocytic bacteria, Ehrlichia phagocytophila, Ehrlichia equi and the agent of human granulocytic ehrlichiosis, after the recent reorganization of the families Rickettsiaceae and Anaplasmataceae in the order Rickettsiales. Tick-borne fever (TBF), which is caused by the prototype of A. phagocytophilum, was first described in 1932 in Scotland. A similar disease caused by a related granulocytic agent was first described in horses in the USA in 1969; this was followed by the description of two distinct granulocy...
McIlwraith CW, Frisbie DD, Kawcak CE.Osteoarthritis (OA) is an important cause of pain, disability and economic loss in humans, and is similarly important in the horse. Recent knowledge on post-traumatic OA has suggested opportunities for early intervention, but it is difficult to identify the appropriate time of these interventions. The horse provides two useful mechanisms to answer these questions: 1) extensive experience with clinical OA in horses; and 2) use of a consistently predictable model of OA that can help study early pathobiological events, define targets for therapeutic intervention and then test these putative thera...
Calisher CH.Of more than 500 arboviruses recognized worldwide, 5 were first isolated in Canada and 58 were first isolated in the United States. Six of these viruses are human pathogens: western equine encephalitis (WEE) and eastern equine encephalitis (EEE) viruses (family Togaviridae, genus Alphavirus), St. Louis encephalitis (SLE) and Powassan (POW) viruses (Flaviviridae, Flavivirus), LaCrosse (LAC) virus (Bunyaviridae, Bunyavirus), and Colorado tick fever (CTF) virus (Reoviridae, Coltivirus). Their scientific histories, geographic distributions, virology, epidemiology, vectors, vertebrate hosts, transm...
Fortune JE.Evidence from several species indicates that the initial stages of follicular growth proceed very slowly. In contrast, the stages after antrum formation are much more rapid. Atresia seems to be most prevalent as follicles approach the size at which they could be recruited for potential ovulation. Although most follicles become atretic around that stage, a few are recruited into a cohort or wave of follicles that continue to grow beyond the stage at which atresia normally occurs. Next, a species-specific number of follicles is selected for dominance. In some species (e.g. rats, primates, pigs),...
Frisbie DD, Cross MW, McIlwraith CW.Histological measurements of the thickness of non-calcified and calcified cartilage, as well as the subchondral bone plate in five locations on the femoral trochlea and medial femoral condyles of species were used in preclinical studies of articular cartilage and compared to those of the human knee. Cadaver specimens were obtained of six human knees, as well as six equine, six goat, six dog, six sheep and six rabbit stifle joints (the animal equivalent of the human knee). Specimens were taken from the lateral trochlear ridge, medial trochlear ridge and medial femoral condyle. After histopathol...
Rosengren Pielberg G, Golovko A, Sundström E, Curik I, Lennartsson J, Seltenhammer MH, Druml T, Binns M, Fitzsimmons C, Lindgren G, Sandberg K....In horses, graying with age is an autosomal dominant trait associated with a high incidence of melanoma and vitiligo-like depigmentation. Here we show that the Gray phenotype is caused by a 4.6-kb duplication in intron 6 of STX17 (syntaxin-17) that constitutes a cis-acting regulatory mutation. Both STX17 and the neighboring NR4A3 gene are overexpressed in melanomas from Gray horses. Gray horses carrying a loss-of-function mutation in ASIP (agouti signaling protein) had a higher incidence of melanoma, implying that increased melanocortin-1 receptor signaling promotes melanoma development in Gra...
Marasas WF, Kellerman TS, Gelderblom WC, Coetzer JA, Thiel PG, van der Lugt JJ.Each of two horses was dosed by stomach tube with culture material on maize of Fusarium moniliforme MRC 826. One horse developed severe hepatosis and mild oedema of the brain after 6 doses of 2.5 g of culture material/kg body mass/day in 7 days. The second horse, in a similar experiment but at a dosage rate of 1.25 g/kg/day, developed mild hepatosis and moderate oedema of the brain. In both animals the brain oedema was particularly noticeable in the medulla oblongata. The mycotoxin fumonisin B1 was extracted and purified from the culture material of F. moniliforme MRC, 826 which contained appr...
Chaucheyras-Durand F, Durand H.The use of probiotics for farm animals has increased considerably over the last 15 years. Probiotics are defined as live microorganisms which can confer a health benefit for the host when administered in appropriate and regular quantities. Once ingested, the probiotic microorganisms can modulate the balance and activities of the gastrointestinal microbiota, whose role is fundamental to gut homeostasis. It has been demonstrated that numerous factors, such as dietary and management constraints, can strongly affect the structure and activities of the gut microbial communities, leading to impaired...
Ahern BJ, Parvizi J, Boston R, Schaer TP.Review the literature for single site cartilage defect research and evaluate the respective strengths and weaknesses of different preclinical animal models. Methods: A literature search for animal models evaluating single site cartilage defects was performed. Variables tabulated and analyzed included animal species, age and number, defect depth and diameter and study duration. Cluster analyses were then used to separate animals with only distal femoral defects into similar groups based on defect dimensions. Representative human studies were included allowing comparison of common clinical lesio...
MacDonald GH, Johnston RE.The initial steps of Venezuelan equine encephalitis virus (VEE) spread from inoculation in the skin to the draining lymph node have been characterized. By using green fluorescent protein and immunocytochemistry, dendritic cells in the draining lymph node were determined to be the primary target of VEE infection in the first 48 h following inoculation. VEE viral replicon particles, which can undergo only one round of infection, identified Langerhans cells to be the initial set of cells infected by VEE directly following inoculation. These cells are resident dendritic cells in the skin, which mi...
Petersen JL, Mickelson JR, Cothran EG, Andersson LS, Axelsson J, Bailey E, Bannasch D, Binns MM, Borges AS, Brama P, da Câmara Machado A, Distl O....Horses were domesticated from the Eurasian steppes 5,000-6,000 years ago. Since then, the use of horses for transportation, warfare, and agriculture, as well as selection for desired traits and fitness, has resulted in diverse populations distributed across the world, many of which have become or are in the process of becoming formally organized into closed, breeding populations (breeds). This report describes the use of a genome-wide set of autosomal SNPs and 814 horses from 36 breeds to provide the first detailed description of equine breed diversity. F(ST) calculations, parsimony, and dista...
Frisbie DD, Ghivizzani SC, Robbins PD, Evans CH, McIlwraith CW.Osteoarthritis in horses and in humans is a significant social and economic problem and continued research and improvements in therapy are needed. Because horses have naturally occurring osteoarthritis, which is similar to that of humans, the horse was chosen as a species with which to investigate gene transfer as a potential therapeutic modality for the clinical treatment of osteoarthritis. Using an established model of equine osteoarthritis that mimics clinical osteoarthritis, the therapeutic effects resulting from intra-articular overexpression of the equine interleukin-1 receptor antagonis...
Frisbie DD, Oxford JT, Southwood L, Trotter GW, Rodkey WG, Steadman JR, Goodnight JL, McIlwraith CW.The current study investigated healing of large full-thickness articular cartilage defects during the first 8 weeks with and without penetration of the subchondral bone using microfracture in an established equine model of cartilage healing. Chondral defects in the weightbearing portion of the medial femoral condyle were made bilaterally; one defect in each horse was microfractured whereas the contralateral leg served as the control. The expression of cartilage extracellular matrix components (Types I and II collagen and aggrecan) was evaluated using histologic techniques, reverse transcriptio...
Yu L, Wei Y, Sun HX, Mahdi AK, Pinzon Arteaga CA, Sakurai M, Schmitz DA, Zheng C, Ballard ED, Li J, Tanaka N, Kohara A, Okamura D, Mutto AA, Gu Y....Dynamic pluripotent stem cell (PSC) states are in vitro adaptations of pluripotency continuum in vivo. Previous studies have generated a number of PSCs with distinct properties. To date, however, no known PSCs have demonstrated dual competency for chimera formation and direct responsiveness to primordial germ cell (PGC) specification, a unique functional feature of formative pluripotency. Here, by modulating fibroblast growth factor (FGF), transforming growth factor β (TGF-β), and WNT pathways, we derived PSCs from mice, horses, and humans (designated as XPSCs) that are permissive for dire...
Lunn DP, Davis-Poynter N, Flaminio MJ, Horohov DW, Osterrieder K, Pusterla N, Townsend HG.Equine herpesvirus-1 is a highly prevalent and frequently pathogenic infection of equids. The most serious clinical consequences of infection are abortion and equine herpesvirus myeloencephalopathy (EHM). In recent years, there has been an apparent increase in the incidence of EHM in North America, with serious consequences for horses and the horse industry. This consensus statement draws together current knowledge in the areas of pathogenesis, strain variation, epidemiology, diagnostic testing, vaccination, outbreak prevention and control, and treatment.
