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.
Neelis DA, Roberts GD.The many advancements in ultrasound technology, including spatial compounding, harmonic imaging, multidimensional and extended field-of-view images, and improvements in transducer capabilities, are used to enhance the ultrasonographic examination of the equine patient. The improvements in software and hardware capabilities help overcome artifacts, improve image quality, and allow better documentation of the examination for follow-up studies. In addition, the ability of smaller, more portable machines to produce better images is ideal for the ambulatory practice setting.
Kakoi H, Kijima-Suda I, Gawahara H, Kinoshita K, Tozaki T, Hirota K, Yoshizawa M.To construct a system for identifying individual horses from urine samples that are submitted for postracing doping tests, we developed a genotyping assay based on 26-plex single-nucleotide polymorphisms (SNPs). DNA was isolated from urine using a commercially available DNA/RNA extraction kit, and SNP genotyping was achieved with a SNaPshot(™) technique. DNA profiles including 26 SNPs were acquired from urine samples and blood/hair samples. Within the studied Thoroughbred population, the 26-plex assay showed a probability of identity of 5.80 × 10(-11). Compared to the conventional short tan...
Brinkmeyer-Langford CL, Cai JJ, Gill CA, Skow LC.Genes within the major histocompatibility complex (MHC) encode proteins involved in innate and adaptive immune responses. Genetic variation in this region can influence the immune response of an individual animal to challenges from a variety of pathogens; however, a complete documentation of genetic variation in the MHC is lacking for most domestic animals, including horses. To provide additional genetic markers for study of the horse MHC, or ELA (equine lymphocyte antigen), we identified 37 polymorphic microsatellite repeats in ELA and used these variations separately and together with publis...
Rehbein S, Visser M, Winter R.Prevalence and intensity of gastrointestinal parasites were studied through a longitudinal survey in 400 horses over a 17-month period in an abattoir in Germany. Three hundred and ten horses (77.5 %) were demonstrated harbouring endoparasites either by direct recovery of parasites from the digestive tract and/or in terms of faecal egg counts (strongyles). The following parasites were found (percentage prevalence, range of counts): Gasterophilus intestinalis larvae (2.25 %, 1-154), Gasterophilus nasalis larvae (0.25 %, 44), Trichostrongylus axei (11.0 %, 1-3,620), Habronema majus (8.0 %; 1...
Spelta CW, Axon JE.The clinical manifestations of equine pituitary pars intermedia dysfunction (PPID) in temperate climates are well described. The classic presentation is that of an older animal with hirsutism, laminitis, poor muscle tone, pendulous abdomen and weight loss. This case series highlights the additional clinical signs of anhidrosis and heat stress with secondary exercise intolerance that were seen as primary presenting problems in equids with PPID in the hot, humid conditions of a tropical climate. The clinical signs resolved with medical treatment for PPID.
Lange CE, Tobler K, Lehner A, Grest P, Welle MM, Schwarzwald CC, Favrot C.Equine penile papillomas, in situ carcinomas, and invasive carcinomas are hypothesized to belong to a continuum of papillomavirus-induced diseases. The former ones clinically present as small grey papules, while the latter 2 lesions are more hyperplasic or alternatively ulcerated. To test the hypothesis that these lesions are papillomavirus-induced, samples of 24 horses with characteristic clinical and histologic findings of penile papillomas or in situ or invasive squamous cell carcinomas were collected. As controls, 11 horses with various lesions--namely, Balanoposthitis (6 cases), melanoma ...
Hinrichs K, Choi YH, Norris JD, Love LB, Bedford-Guaus SJ, Hartman DL, Velez IC.To evaluate the efficiency of foal production following intracytoplasmic sperm injection (ICSI) and blastocyst culture of oocytes from mares that died or were euthanized under field conditions. Methods: Prospective case series. Methods: 16 mares (age, 3 to 19 years) that died or were euthanized for various causes. Methods: Ovaries were collected immediately before euthanasia (n = 10) or after death (6). Ovaries were transported to the laboratory for oocyte recovery (15 mares), or oocytes were recovered at a remote location and shipped to the laboratory (1). Oocytes underwent ICSI, and presumpt...
Kumar S, Yokoyama N, Kim JY, Bork-Mimm S, Inoue N, Xuan X, Igarashi I, Sugimoto C.Theileria equi is a tick-transmitted intraerythrocytic protozoan parasite in equids. Equine merozoite antigen (EMA)-1 and EMA-2 of T. equi have been identified as immunodominant proteins co-expressed on the surface of extra-erythrocytic merozoites. Additionally, only the EMA-2 is shed into the cytoplasm of infected erythrocyte or inside the erythrocytic membrane during their early developmental stage. In this study, we initially performed West-Western blot analysis on Triton X-100-insoluble erythrocytic skeleton collected from a healthy horse, using a glutathione S-transferase (GST)-tagged rec...
Yuda Y, Kasashima Y, Kuwano A, Sato K, Hattori S, Arai K.Upregulation of hyaluronidase 2 (HYAL2), one of somatic hyaluronidase (HAase), was demonstrated in granulation tissue during the healing of equine superficial digital flexor tendon injuries. The activity of HAase was assessed by hyaluronan (HA)-containing gel zymography and in situ zymography using frozen sections obtained from normal and injured tendon tissues. Elevated HAase activity was identified in the extract from the tendinopathic tissues, with lower levels of the activity in normal tendons. In situ zymography using fluorescently-labeled HA demonstrated HAase activity in the granulation...
Farkas R, Tánczos B, Gyurkovszky M, Földvári G, Solymosi N, Edelhofer R, Hornok S.The prevalence of Theileria equi infection was studied in 324 healthy horses from 27 farms in Hungary with cELISA and IFAT and the blood samples of 101 horses selected randomly were also examined by PCR. The results indicate that there are many stud farms where one or more horses are infected with T. equi. Among 27 farms 17 (67.9%) were found to have seropositive horses. The seroprevalence of theileriosis among the tested stud farms ranged between 0 and 100%. No marked differences were found in seropositivity between geographical areas. The overall prevalence of positive samples was 32.0% with...
McCarrel TM, Minas T, Fortier LA.Numerous methods are available for platelet-rich plasma (PRP) generation, but evidence defining the optimum composition is lacking. We hypothesized that leukocyte-reduced PRP would result in lower inflammatory cytokine expression compared with concentrated-leukocyte PRP and that maintaining the platelet:white blood cell (WBC) ratio would compensate for the effect of increased WBC concentration. Methods: Blood and flexor digitorum superficialis tendons were collected from young adult horses. Three PRP groups were generated with the same platelet concentration but different WBC concentrations: i...
Yamout SZ, Magdesian KG, Tokarz DA, le Jeune SS.This is a report of a 12-year-old Swedish Warmblood gelding with a ruptured esophageal pulsion diverticulum associated with atypical clinical signs of colic and septic peritonitis on presentation. The location of this diverticulum at the hiatus was unique and was most likely responsible for the unusual presentation of this horse. Diverticule de Zenker intrathoracique chez un cheval. Ceci est un rapport d’un hongre de race Swedish Warmblood âgé de 12 ans présentant un diverticule de Zenker perforé associé à des signes cliniques atypiques de coliques et de péritonite septique à la pré...
MacFarlane PD, Mosing M.This case series is the first report of the use of CPAP (continuous positive airway pressure) ventilation in adult horses. Two horses and 3 ponies anesthetized for orthopedic procedures in lateral recumbency received 10 cm H(2)O CPAP. During anesthesia, arterial oxygen partial pressure tended to increase and arterial carbon dioxide pressure tended to increase despite increased minute ventilation index. The measured cardiovascular parameters were within physiologic limits. Cette série de cas est le premier rapport sur l’utilisation de la ventilation spontanée en pression positive continue ...
McD○ LA.Stem cell therapy and cell-based therapies using other progenitor cells are becoming the treatment of choice for many equine orthopedic lesions. Important criteria for obtaining autogenous equine progenitor cells in vitro for use in clinical cell-based therapy include the ability to isolate and expand cells repeatedly to high numbers (millions) required for therapy, in a clinically relevant time frame. Cells must also maintain their ability to differentiate into the tissue type of choice. The objective of this study was to compare isolation and expansion techniques for preparation of periostea...
Leiva M, Felici F, Carvalho A, Ramis A, Peña T.An 11-year-old Arabian mare was presented for investigation of a visible, pale-colored intraocular mass in the right eye. Results: An intraocular mass was detected clinically and ultrasonographically as originating from the superior temporal quadrant of the ciliary body and iris and causing secondary glaucoma. The echodense mass was occupying the majority of the vitreous chamber and extended into the anterior chamber. The left eye appeared normal. Results: Enucleation was recommended for therapeutic and diagnostic purposes. No adjuvant treatment was given. Histopathological examination demonst...
Penrod LV, Allen RE, Turner JL, Limesand SW, Arns MJ.Increased secretion of prostaglandin F(2)α (PGF(2)α) within the uterus because of uterine inflammation can cause luteolysis and result in early embryonic loss. Supplementation with polyunsaturated fatty acids (PUFAs) has been shown to influence PG production in many species, although the effects on the mare remain unknown. The present study aimed to determine fatty acid uptake in equine endometrial explants and evaluate their influence on PG secretion and expression of enzymes involved in PG synthesis in vitro. Equine endometrial explants were treated with 100 μM arachidonic acid, eicosapen...
Garcia-Etxebarria K, Jugo BM.Endogenous retroviruses (ERVs) are proviral phases of exogenous retroviruses that have become incorporated into the host genome. Little is known about ERVs in the horse genome. By combining 3 bioinformatic approaches, we detected 1947 putative ERVs in the horse genome. These equine ERVs are not scattered randomly across the genome and are especially abundant in the X chromosome. Based on phylogenetic relationships, some of these equine ERVs were classified into 15 previously uncharacterized families of Classes I, II and III. Compared with the cow and other species, the horse genome appears to ...
Duesterdieck-Zellmer KF, Driscoll N, Ott JF.To determine concentration-dependent effects of tiludronate on cartilage explants incubated with or without recombinant equine interleukin-1β (rEq IL-1). Methods: Articular cartilage explants from the femorotibial joints of 3 young adult horses. Methods: Cartilage explants were incubated with 1 of 6 concentrations (0, 0.19, 1.9, 19, 190, or 1,900 mg/L) of tiludronate and with or without rEq IL-1 (0.01 ng/mL) for 96 hours. Prostaglandin E(2) (PGE(2)) concentrations in culture medium and explant digests were analyzed via PGE(2) enzyme immunoassay. Sulfated glycosaminoglycan (sGAG) concentration...
Klein C, Donahue JM, Sells SF, Squires EL, Timoney PJ, Troedsson MH.To determine the impact of antimicrobial-containing semen extender on the growth of Taylorella equigenitalis in semen culture-positive for contagious equine metritis (CEM) and the development of CEM after artificial insemination with CEM-positive semen extended with antimicrobial-containing semen extender. Methods: Prospective study. Methods: 21 mature mares free of CEM, 1 mature stallion experimentally infected with CEM, and semen from a stallion naturally infected with CEM. Methods: CEM-positive semen was incubated in semen extender with and without antimicrobials (amikacin [final concentrat...
Patterson AL, Squires EL, Hansen TR, Bouma GJ, Bruemmer JE.Maternal recognition of pregnancy is a physiological process that primarily describes endometrial responses to a conceptus. Recognition of a conceptus prevents the release of prostaglandin F(2α) , thereby ensuring survival of the corpus luteum and continued progesterone production. Exactly how this occurs in the mare is poorly understood. Because prostaglandin F(2α) is a pro-inflammatory hormone, we hypothesized that differential gene expression in the endometrium at the time of maternal recognition reflects an anti-inflammatory event leading to decreased prostaglandin F(2α) secretion. Mare...
Breton A, Sharma R, Diaz AC, Parham AG, Graham A, Neil C, Whitelaw CB, Milne E, Donadeu FX.Pluripotent stem cells offer unprecedented potential not only for human medicine but also for veterinary medicine, particularly in relation to the horse. Induced pluripotent stem cells (iPSCs) are particularly promising, as they are functionally similar to embryonic stem cells and can be generated in vitro in a patient-specific manner. In this study, we report the generation of equine iPSCs from skin fibroblasts obtained from a foal and reprogrammed using viral vectors coding for murine Oct4, Sox2, c-Myc, and Klf4 sequences. The reprogrammed cell lines were morphologically similar to iPSCs rep...
Rickey EJ, Cruz AM, Trout DR, McEwen BJ, Hurtig MB.To determine whether a single contusive impact injury to the palmar aspect of the metacarpus would progress to post-traumatic osteoarthritis or palmar osteochondral disease in horses. Methods: 12 horses. Methods: In each horse, an impact injury was created on the palmar aspect of the medial metacarpal condyle of 1 randomly chosen limb with an impactor device under arthroscopic and fluoroscopic guidance. The opposite limb was sham operated as a control. A low to moderate amount of forced exercise was instituted, and horses were evaluated clinically via lameness examinations weekly for 5 months,...
Casella S, Piccione D, Ielati S, Bocchino EG, Piccione G.The aim of this study was to assess the anion transport in equine erythrocytes through the measurement of the sulfate uptake operating from band 3 using different experimental temperatures and buffer solutions. Blood samples of six clinically healthy horses were collected via jugular vein puncture, and an emochrome-citometric examination was performed. The blood was divided into four aliquots and by centrifugation and aspiration the plasma and buffy coat were carefully discarded. The red blood cells were washed with an isosmotic medium and centrifuged. The obtained cell suspensions were incuba...
Steelman SM, Chowdhary BP.Equine laminitis is a devastating disease that causes severe pain in afflicted horses and places a major economic burden on the horse industry. In acute laminitis, the disintegration of the dermal-epidermal junction can cause the third phalanx to detach from the hoof wall, leaving the horse unable to bear weight on the affected limbs. Horses that survive the acute phase transition into a chronic form of laminitis, which is often termed "founder". Some evidence suggests that chronic laminar inflammation might be associated with alterations in the endocrine and immune systems. We investigated th...
Black B, Cribb NC, Nykamp SG, Thomason JJ, Trout DR.Artefacts caused by regional anaesthesia can influence image interpretation of ultrasonography and nuclear scintigraphy. Perineural and intrasynovial anaesthesia are commonly performed prior to magnetic resonance imaging (MRI); and the effects on MR images, if any, are unknown. Objective: To determine if perineural and intrasynovial anaesthesia of structures in the equine foot cause iatrogenic changes detectable with MRI. Methods: A baseline MRI examination of both front feet was performed on 15 horses, 2-6 days prior to mepivacaine injection adjacent to the lateral and medial palmar digital n...
McCue PM, Farquhar VJ, Carnevale EM, Squires EL.Deslorelin implants, approved for use in inducing ovulation in mares, have been associated with prolonged interovulatory intervals in some mares. Administration of prostaglandins in the diestrous period, following a deslorelin-induced ovulation, has been reported to increase the incidence of delayed ovulations. The goals of the present study were: (1) to determine the percentage of mares given deslorelin that experience delayed ovulations with or without subsequent prostaglandin treatment, and (2) to determine if removal of the implant 48 h after administration would effect the interval to sub...
Barros ML, Borges AMC, Oliveira De ACS, Lacerda W, O Souza De A, Aguiar DM.The prevalence of equine infectious anaemia (EIA) in the three biomes of the state of Mato Grosso (Amazon, Cerrado and Pantanal) was estimated. Serum samples were collected from 3,858 equines in 1,067 herds between Septemberand December 2014. The agar gel immunodiffusion (AGID) assay was used to detect EIA virus antibodies, and if a herd contained a seropositive animal itwas classified as a focus. The prevalence rates were 17.2% (95% confidence interval [CI]: 14.9-19.8%) for herds and 6.6% (95% CI: 5.8-7.5%) for animals. The Pantanal region showed the highest prevalence rates: 36.1% (95% CI: 3...
RANDALL CC, ORR MF, SCHELL FG.Intracellular organisms resembling Histoplasma capsulatum have been observed in apparently normal amnio-allantoic membrane and adult horse spleen maintained in tissue culture.
The significance of this finding and comparison with another fungus Cryptococcus jarciminosus is discussed.
Rush BR, Flaminio MJ.Nonspecific immunomodulators are substances that induce non-antigen-specific enhancement of the body's native or acquired defense mechanisms. Immunomodulant preparations are most often used for treatment of chronic, viral, or bacterial infection with evidence of secondary immunosuppression. The proposed mechanism of action of these products is macrophage activation and subsequent release of cytokines that enhance humoral and cell-mediated immunity. In equine medicine, nonspecific immunostimulant products are used for prevention and treatment of infectious respiratory disease and treatment of s...
Weiss R, Böhm KH, Mumme J, Nicklas W.Over a thirteen year period (1965 to 1977) a total of 4790 skin scrapings and hair samples of animals were examined mycologically. 887 strains of dermatophytes were isolated out of 885 of these samples (= 18,5%). Most frequently Trichophyton verrucosum was identified in samples from cattle, followed by Microsporum canis isolated from cats, dogs and zoo animals. T. mentagrophytes was mainly found on guinea pigs, chinchillas and dogs and T. equinum on horses. Although the total number of the samples examined within the last 8 years increased, the total of the dermatophytes isolated remained prop...
Paradis MR.Septicemia is the second most commonly diagnosed problem in the equine neonate, superseded only by the problem of inadequate transfer of maternal antibodies. This article reviews the factors that may put a foal at high risk for developing sepsis, the diagnostic tools used to identify these animals, some of the sequelae of sepsis, and the therapeutic modalities available to the clinician.
Stewart DR, Nevins B, Hadas E, Vandlen R.Relaxin, a polypeptide hormone normally associated with pregnancy, has been purified from many species, and the sequence determined for a growing number. Equine relaxin has been previously purified by acetone extraction, gel filtration, and ion exchange chromatographies. In an attempt to develop a more rapid and efficient method for relaxin purification, the use of affinity chromatography coupled with HPLC was explored. Monoclonal antibodies were raised against highly purified equine relaxin; large quantities of antibody were obtained by ascites production and attached to a solid phase support...
Milner PI, Sidwell S, Talbot AM, Clegg PD.Primary lesions of the deep digital flexor tendon (DDFT) within the digit are an important cause of lameness diagnosed using magnetic resonance imaging (MRI) but appearance of these lesions over time has not been documented. Objective: To determine whether the magnetic resonance (MR) appearance of different primary DDFT lesions alter over a 6 month period and whether lesion type is a determinant of these changes. Methods: Cases included had lameness attributable to a primary lesion involving the DDFT in the digit diagnosed on MRI. Lesions were typed into parasagittal, dorsal border and core le...
Fiala SM, Pimentel CA, Mattos AL, Gregory RM, Mattos RC.Our objective was to determine whether the concentration of cooled sperm inseminated influenced sperm transport and intensity of the uterine inflammatory reaction 2, 4 and 24h after insemination. Experimental subjects were 189 estrous mares with a dominant follicle > or =35 mm in diameter and no bacterial growth or neutrophils detected in uterine smears. Each mare was randomly assigned to receive one of the following intrauterine treatments (volume, 20 mL): insemination with 5x10(6) mL(-1) or 25x10(6) mL(-1) or 50x10(6) mL(-1) sperm diluted in 3 mL seminal plasma (SP) and 17 mL skim milk; s...
Scholes SF, Holliman A, May PD, Holmes MA.Fell pony foals developed a syndrome of anaemia, immunodeficiency and peripheral ganglionopathy. They became ill in the second or third week, and died in the second or third month of life. Clinical and pathological investigations revealed severe anaemia associated with small numbers of late erythroid precursors in bone marrow, small thymi, an absence of secondary lymphoid follicles, a lack of plasma cells and neuronal chromatolysis involving trigeminal, cranial mesenteric and dorsal root ganglia. Some of the foals had cryptosporidial enteritis and adenoviral bronchopneumonia and pancreatitis. ...
Laabassi F, Amelot G, Laugier C, Zientara S, Nasri AM, Hans A.In order to determine the prevalence of equine viral arteritis in Algeria, 268 sera from non-vaccinated horses were collected from the western and eastern regions. Serological analysis of the sera, which were collected from 2009 to 2011, was performed using the virus neutralisation test, as described by the World Organisation for Animal Health. Overall, 20 sera (7.46%) were seropositive, 152 (56.71%) were negative and 96 sera (35.82%) were cytotoxic. Equine arteritis virus (EAV) seroprevalence was significantly higher in the western region (Tiaret) than in the eastern region (Barika and El-Eul...
Klein C, Scoggin KE, Troedsson MH.Establishment of pregnancy is critically dependent upon a precisely orchestrated embryo-maternal interaction leading to a receptive uterine environment. The up-regulation of the interferon-stimulated protein 15 kDa (ISG15) during pregnancy has been described in various species and has been hypothesized to be part of the molecular repertoire that makes the uterus receptive to conceptus development. In the current study, the expression of ISG15 and enzymes involved in ISG15ylation was examined at the mRNA and protein level in equine endometrium at Day 14 of the luteal phase and at Day 14 and 50 ...
Lampe V, Dierks C, Komm K, Distl O.In this study we present a newly detected QTL associated with osteochondrosis in Hanoverian warmblood horses on equine chromosome 18 (ECA18). We developed a highly polymorphic and evenly distributed marker set on ECA18 employing the horse genome assembly EquCab2. The marker set included 11 newly developed microsatellites. Average polymorphism information content was 62.1% at an average spacing of 3 Mb. For genotyping of this marker set comprising a total of 27 highly polymorphic microsatellites, we used the same 14 paternal half-sib families as in the previous whole genome scan. The chromosome...
Parsons KJ, Wilson AM.MP3 recorders are readily available, small, lightweight and low cost, providing the potential for logging analogue hoof mounted accelerometer signals for the characterisation of equine locomotion. These, however, require testing in practice. Objective: To test whether 1) multiple MP3 recorders can maintain synchronisation, giving the ability to synchronise independent recorders for the logging of multiple limbs simultaneously; and 2) features of a foot mounted accelerometer signal attributable to foot-on and foot-off can be accurately identified from horse foot mounted accelerometers logged di...
Bowden A, Boynova P, Brennan ML, England GCW, Mair TS, Furness WA, Freeman SL, Burford JH.The study aim was to describe conditions seen 'out-of-hours' in equine practice. This was a retrospective case series of first opinion 'out-of-hours' cases seen at two equine practices between 2011 and 2013. Data were retrieved on case presentation, diagnostic testing, treatment administered and outcome, and diseases categorised using a systems-based coding system. A hierarchical logistic regression, formulated using a generalised linear model, was used to identify clinical variables associated with a binary outcome of 'critical' cases (required hospitalisation or euthanasia or died). Data fro...
Liu S, Jiang S, Dong XG, Cui R, Ling Y, Zhao C.The Debao pony is a well-known dwarf horse breed in China. High-mobility group AT-hook 2 (HMGA2) gene is regarded as one of the important candidate genes regulating body height in horses. The aim of this study was to study the association between mutations in HMGA2 gene and withers height in Debao ponies. The polymorphisms in all exons and partial introns of the HMGA2 gene were screened with sequencing across 180 Debao ponies. And the association between the DNA variants and withers height was analyzed. Seven genetic variants were identified in HMGA2 gene, including six novel variants. Among t...