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.
HOLLISTER AC, LONGSHORE WA, DEAN BH, STEVENS IM.For the most part, epidemiologic phenomena observed in the outbreak of encephalitis in 1952 accorded with patterns that had been apparent in previous years. Ninety-seven per cent of the 414 laboratory-confirmed cases of western equine and St. Louis encephalitis in humans occurred in the 20 Central Valley counties. The cases of western equine encephalomyelitis in horses were generally scattered over the state. In the Central Valley most of the cases in horses were in animals less than two years of age; elsewhere the incidence was higher in older horses.There were no laboratory-confirmed cases o...
Güvenc K, Reilas T, Katila T.It is unclear whether AI of mares deep into the uterine horn causes more or less inflammation of the endometrium than conventional AI. Thus, we compared uterine inflammatory reactions of mares inseminated with two different doses of frozen-thawed semen into the tip of the uterine horn (UH) ipsilateral to the preovulatory follicle with those of mares inseminated into the uterine body (UB). Thirty-two mares were assigned to one of four groups (eight mares/group): UB20=AI into UB, 20 x 10(6)sperm/0.5 mL; UB200=AI into UB, 200 x 10(6)sperm/0.5 mL; UH20=AI into UH, 20 x 10(6)sperm/0.5 mL; UH200=AI ...
Alitalo I, Kärkkäinen M.Ataxia caused by a focal compression of the cervical spinal cord was diagnosed in four young standardbred trotting horses. Diagnosis was verified by myelography. Changes in the cervical vertebral column were studied using microradiographic and histologic methods. In the vertebrae involved, there was irregularity of the cartilaginous growth zone, cracks with a loose fragment and disturbance in the enchondral ossification. These changes resemble osteochondrosis. Porous appearance in lateral and ventral funiculi as well as mural calcified plaques in the small vessels of the white matter were foun...
Chang Y, Maylin GM, Matsumoto G, Neades SM, Catlin DH.Methods have been developed to screen for and confirm darbepoetin alfa, recombinant human EPO, and methoxy polyethylene glycol-epoetin β (PEG-epoetin β) in horse plasma. All three methods screen samples with an enzyme-linked immunosorbent assay (ELISA) and confirm by liquid chromatography-tandem mass spectrometry (LC-MS/MS). This report focuses on PEG-epoetin β. The ELISA assay was able to detect PEG-epoetin β at 0.02 ng/mL in 50 µL of horse plasma. Many samples had high background levels of immunoreactivity; however, introducing polyethylene glycol 6000 (PEG 6000) into the samples before...
Wang LF, Gould AR, Selleck PW.Full-length cDNA clones coding for the matrix (M) and fusion (F) proteins of equine morbillivirus (EMV) were isolated by RT-PCR, and expressed in Escherichia coli using two different expression systems. Western blot analysis indicated that the M and F proteins, expressed either by itself or as fusion proteins with glutathione S-transferase (GST), were insoluble and degraded after expression. Analysis of the degradation pattern of recombinant M protein suggested that the N-terminus of the matrix protein might be more stable and antigenic than the C-terminal region. Therefore a third system was ...
Battsetseg B, Lucero S, Xuan X, Claveria F, Byambaa B, Battur B, Boldbaatar D, Batsukh Z, Khaliunaa T, Battsetseg G, Igarashi I, Nagasawa H....Babesia equi (EMA-1) and Babesia caballi (BC48) gene fragments were amplified by polymerase chain reaction (PCR), in blood samples, and partially fed-females and egg and larval progenies of Dermacentor nuttalli, collected from horses in Altanbulag, Tuv Province, Mongolia. While Babesia parasite DNA was detected in some horse blood samples during the first PCR, all positive cases in partially fed-female ticks, eggs and larvae were confirmed by nested PCR. Present study reinforces earlier similar findings in unfed D. nuttalli ticks collected from an open space vegetation in Bayanonjuul, Tuv Prov...
Deeg CA, Hauck SM, Amann B, Kremmer E, Stangassinger M, Ueffing M.Equine recurrent uveitis (ERU) is a valuable model for autoimmune diseases, since it develops frequently and occurs spontaneously. We investigated the overall expression level of three major retinal autoantigens in normal retinas and various ERU stages. Analysis of retinal proteomes of both, healthy and diseased retinas revealed an almost unaffected expression of IRBP, S-antigen and cRALBP in ERU cases. Validation of these findings with western blots and immunohistochemistry confirmed constant to increased expression of these autoantigens, although loss of their physiological expression sites ...
Rendle DI, Hughes KJ, Doran GS, Edwards SH.To determine the pharmacokinetics of pergolide after IV administration to horses. Methods: 8 healthy adult horses. Methods: Pergolide mesylate was administered IV at a dose of 20 μg/kg (equivalent to 15.2 μg of pergolide/kg) to each horse, and blood samples were collected over 48 hours. Pergolide concentrations in plasma were determined by means of high-performance liquid chromatography-tandem mass spectrometry, and pharmacokinetic parameters were determined on the basis of noncompartmental methods. Results: After IV administration of pergolide, mean ± SD clearance, elimination half-life, a...
Touratier L.There is increasing interest in many parts of the world in trypanosomoses other than those transmitted by tsetse flies, as shown by numerous research projects and field studies. The refinement of techniques for studying the behaviour of trypanosomes (techniques of molecular biology) in axenic culture or in the parasitised host has led to progress in diagnosis and immunology, and a rational approach to chemotherapy and chemoprophylaxis of these infections. Field trials of enzyme-linked immunosorbent assays in Africa, Asia and South America have shown that these tests may now be regarded as reli...
Sahmi F, Nicola E, Price CA.The objective was to establish a cell line-based bioassay for FSH in horse serum for screening samples with high eCG bioactivity. A cell line (HEK293) was transiently cotransfected with an FSH reporter expression plasmid and a cAMP-responsive β-galactosidase reporter plasmid. Cells were bulk frozen, and thawed for assay purposes. This assay was specific for FSH, with no cross-reaction with LH or insulin-like growth factor-1. Standard curves (eCG) and serum samples from pregnant mares passed parallel line bioassay validity tests (linearity and parallelism). Estimates of bioactivity with this b...
Martino NA, Marzano G, Mastrorocco A, Lacalandra GM, Vincenti L, Hinrichs K, Dell Aquila ME.Time-lapse imaging was used to establish the morphokinetics of equine embryo development to the blastocyst stage after invitro oocyte maturation (IVM), intracytoplasmic sperm injection (ICSI) and embryo culture, in oocytes held overnight at room temperature (22-27°C; standard conditions) before IVM. Embryos that developed to the blastocyst stage underwent precleavage cytoplasmic extrusion and cleavage to the 2-, 3- and 4-cell stages significantly earlier than did embryos that arrested in development. We then determined the rate of blastocyst formation after ICSI in oocytes held for 2 days at ...
Nielsen MK, Littman BA, Orzech SW, Ripley NE.Equine cyathostomins are ubiquitous in grazing horses around the world and a main target in parasite control programs. Anthelmintic resistance has been reported with increasing frequency in these parasites over the past decades, and recent findings of fulminant resistance to the macrocyclic lactone class have raised severe concerns. This study aimed to evaluate ivermectin efficacy in cohorts of yearlings and mares present on four different farms in Central Kentucky. Strongylid egg counts were determined with an automated egg counting system, and the percent fecal egg count reduction (FECR) was...
Timoney PJ, Dillon PB, Geraghty VP, McArdle JF.Aspects of experimental transmission of the causal bacterium of contagious equine metritis (CEM) to albino Swiss mice were investigated. Whereas infection was established in the majority of female mice, the organism was recovered from only a limited number of male mice after challenge. No clinical evidence of infection was observed in the experimental mice. There was only one instance of presumptive venereal transmission of the CEM bacterium. One third of infected females conceived and had normal litters.
Wilde H, Chutivongse S.Four hundred nineteen patients exposed to rabies in Thailand were treated with equine rabies immune globulin (ERIG) manufactured by Sclavo of Italy, a product also licensed in the United States of America. They were followed for a minimum of 1 month after ERIG injection and rabies vaccine administration. Adverse serum sickness-like reactions were noted in 15 patients (3.58%). These were clinically acceptable and only 1 of these patients required corticosteroid therapy and short term hospitalization for serum sickness. ERIG is approximately 1/10 of the cost of human rabies immune globulin (HRIG...
Breuil MF, Joseph M, Petry S.The gold standard method to isolate and identify Taylorella equigenitalis, the contagious agent of equine metritis, is the culture method according to the World Organisation for Animal Health Terrestrial Manual. No selective T. equigenitalis chocolate agar medium has been developed since the 1980s and the existing media show limited performances due to the fastidious nature of T. equigenitalis and the presence of interfering bacteria in the genital tract of equines. Here, the growth rates of 6 T. equigenitalis strains and 7 non-T. equigenitalis strains were compared on Timoney's selective medi...
Simon O, Laverty S, Bouré L, Marcoux M, O Szöke M.To describe the outcome after arthroscopic electrosurgical excision of axial osteochondral (OC) fragments of the proximal plantar aspect of the 1st phalanx (P1) in horses. Methods: Retrospective study. Methods: Twenty-three Standardbred racehorses. Methods: Medical records of Standardbred racehorses that had arthroscopic dissection of axial OC fragments of the proximal plantar aspect of P1 with electrocautery probes were reviewed. Horses were positioned in dorsal recumbency; a 1.5% glycine solution was used to maintain joint distension. The arthroscope portal was in the proximal plantar joint ...
Busechian S, Conti MB, Sgorbini M, Conte G, Marchesi MC, Pieramati C, Zappulla F, Vitale V, Rueca F.Equine gastric ulcer syndrome (EGUS) is the most common disease of the stomach in horses and treatment is based on the oral administration of omeprazole for at least 28 days. Aim of this study was to compare the efficacy of two formulations of oral omeprazole-powder paste and gastro-enteric resistant granules-in the treatment of naturally occurring gastric ulcers in racehorses. Thirty-two adult racehorses, aged between 2 and 10 years old, with clinical signs of EGUS were included in this blinded, randomized clinical trial. Two gastroscopies were performed to evaluate gastric lesions in the squ...
Tou K, Cawley A, Bowen C, Bishop DP, Fu S.The current approach to equine anti-doping is focused on the targeted detection of prohibited substances. However, as new substances are rapidly being developed, the need for complimentary methods for monitoring is crucial to ensure the integrity of the racing industry is upheld. Lipidomics is a growing field involved in the characterisation of lipids, their function and metabolism in a biological system. Different lipids have various biological effects throughout the equine system including platelet aggregation and inflammation. A certain class of lipids that are being reviewed are the eicosa...
Williamson RM, Beveridge I, Gasser RB.To compare the sensitivities of three coprological techniques for the diagnosis of Anoplocephala perfoliata infection in horses and to assess the value of the methods for diagnosis of horses at risk of clinical cestodiasis. Methods: Faecal samples were collected from necropsied horses with or without A perfoliata infection and examined using one sedimentation and two different flotation methods. The coprological results were compared with worm counts performed at necropsy of the horses and the degree of mucosal damage. In addition, the efficiency of recovery of A perfoliata eggs from faeces wa...
Hamblin C, Salt JS, Mellor PS, Graham SD, Smith PR, Wohlsein P.Investigations have been carried out to elucidate the possible role of the donkey in the epidemiology of African horse sickness (AHS). These studies have shown that despite the absence of pyrexia or other observable clinical signs, donkeys become infected with virulent AHS virus serotype 4 (AHSV 4) and that they develop a viraemia which can persist for at least 12 days, albeit at a comparatively lower titre than that recorded for similarly infected ponies. AHSV 4 showed a similar tissue tropism in the pony and donkey but the virus appeared to replicate less efficiently in donkey tissues. The o...
Moriyama H, Kasashima Y, Kuwano A, Wada S.To identify morphologically the locations of equine corneal epithelial stem cells (CESCs) and to culture these cells. Methods: We studied the eyes of 12 adult thoroughbred horses. Methods: Eye tissues were immunostained for two positive stem cell markers (p63, CK14) and one negative marker (CK3) to identify the locations of CESCs, so we could compare their immunostaining patterns with those of human stem cells previously reported. We compared the proliferation rates and morphological features of epithelial cells isolated from the corneal limbus and central cornea. Results: Undifferentiated cel...
Kalck KA, Frank N, Elliott SB, Boston RC.To ascertain whether laminitis can be induced via administration of oligofructose (OF) at doses of 5.0 and 7.5 g/kg in horses and to assess glucose and insulin dynamics before and after treatment. Methods: 19 adult horses. Methods: Horses were fed OF (1.0 g/kg) mixed with oats for 6 days. Oligofructose at doses of 5.0 and 7.5 g/kg was then mixed with 4 L of water and administered (0 hours) to 8 (group A) and 4 (group B) horses, respectively, via nasogastric intubation; 8 horses received water alone. One horse in group A that did not develop laminitis was subsequently treated again and included...
Yoon J, Park T, Kim A, Park J, Park BJ, Ahn HS, Go HJ, Kim DH, Lee JB, Park SY, Song CS, Lee SW, Choi IS.Equine parvovirus-hepatitis (EqPV-H) is one of the etiological agents of Theiler's disease, causing fulminant hepatitis; however, its transmission route and pathogenesis remain unclear. In the present study, we aimed to determine EqPV-H shedding in oral/nasal/vaginal swabs or semen samples from horses living in Korea using nested polymerase chain reaction. We then used the data obtained to investigate various risk factors associated with EqPV-H including viral shedding, hepatopathological changes, and genetic diversity. Our data revealed occurrence of EqPV-H shedding in these animals (oral: 3/...
Glass K, Barnes B.When novel disease outbreaks occur in livestock, policy makers must respond promptly to eliminate disease, and are typically called on to make control decisions before detailed analysis of disease parameters can be undertaken. We present a flexible metapopulation model of disease spread that incorporates variation in livestock density and includes occasional high-mixing locations or events, such as markets or race meetings. Using probability generating functions derived from this branching process model, we compare the likely success of reactive control strategies in eliminating disease spread...
Sugo T, Kato H, Iwanaga S, Fujii S.On incubation of purified horse plasma high-molecular-weight kininogen with purified plasma kallikrein, three new peptides, named fragment 1.2, fragment 1 and fragment 2, were released, in addition to the vasopeptide, bradykinin. Fragment 2 contained an extremely high level of histidine, in which eleven residues out of the total 48 residues were characterized. Thus the result proves the existence of the histidine-rich region in horse high-molecular-weight kininogen, which is similar to the region previously identified in bovine high-molecular-weight kininogen. Moreover, we have identified a ne...
Brandly JE, Midon M, Douglas HF, Hopster K.Equine peri-anesthetic mortality is higher than that for other commonly anesthetized veterinary species. Unique equine pulmonary pathophysiologic aspects are believed to contribute to this mortality due to impairment of gas exchange and subsequent hypoxemia. No consistently reliable solution for the treatment of peri-anesthetic gas exchange impairment is available. Flow-controlled expiration (FLEX) is a ventilatory mode that linearizes gas flow throughout the expiratory phase, reducing the rate of lung emptying and alveolar collapse. FLEX has been shown to improve gas exchange and pulmonary me...
McCalla TL, Moore CP, Collier LL.A 5-year-old Pony of America mare was referred for evaluation of inflamed upper and lower right eyelids. Squamous cell carcinoma of the eyelids and ulcerative keratitis secondary to self-trauma were diagnosed. Initial treatment of the eyelid neoplasia with 2 applications of cryotherapy failed to resolve the lesions, and immunotherapy with bacillus of Calmette-Guerin (BCG) was instituted. Multiple injections of BCG over a 17-week period resulted in progressive shrinkage of the tumor mass, but regional metastasis to the ipsilateral submandibular lymph node occurred. Six months later, ocular neop...
Finno CJ, Spier SJ, Valberg SJ.The recent development of equine genome maps by the equine genome community and the complete sequencing of the horse genome performed at the Broad Institute have accelerated the pace of genetic discovery. This review focuses on genetic diseases in the horse for which a mutation is currently known, including hyperkalemic periodic paralysis, severe combined immunodeficiency, overo lethal white syndrome, junctional epidermolysis bullosa, glycogen branching enzyme deficiency, malignant hyperthermia, hereditary equine regional dermal asthenia, and polysaccharide storage myopathy. Emphasis is placed...
Schellenberg LM, Bonicelli J, Hochheim I, Regenthal R, Abraham G.The β-adrenergic receptor (β-AR) plays an important role in regulating a variety of cell and organ functions in different animal species and is an important target in asthma pathogenesis and therapy. The β-AR expression and function in equine bronchial epithelial cells (EBEC) were not known but innervation and significant decrease in receptor level were reported in the equine bronchial tissues from asthmatic horses. I-iodocyanopindolol (ICYP) binding studies were undertaken in primary freshly isolated and cultured EBEC to identify the presence of the β-ARs. The receptor distribution was as...
Gobato MLM, Segabinazzi LGTM, Scheeren VFC, Bandeira RS, Freitas-Dell'Aqua CP, Dell'Aqua JA, Papa FO.Artificial insemination using cooled-transported semen has marked importance in equine breeding programs around the world, and the high value of mules has generated avid interest in donkey semen biotechnology. However, donkey semen cools poorly in commercially available equine extenders. Therefore, this study aimed to develop approaches to improve the ability of donkey semen to tolerate cooling. Ejaculates of seven donkeys (n = 21) were cooled at 5°C for 48 h in three different extenders (milk-based, SM; sodium caseinate-based, SC; or egg yolk-based, EY) in the presence or absence of seminal ...
Keg PR, Barneveld A, Schamhardt HC, van den Belt AJ.To answer the question whether it is possible to differentiate, by means of a high plantar nerve block in the hind limb, flexor tendon lameness from a suspensory ligament lameness, mid-plantar tendinitis or desmitis was induced with collagenase in five Standardbred horses in two trials. Before the induction of lameness, and on the fourth (D4) and fourteenth day (D14) after the induction of lameness the horses were evaluated subjectively (clinical lameness score), objectively (ground reaction force (GRF) measurements), and ultrasonographically. Clinical evaluation and GRF measurements were also...