Disease etiology in horses refers to the study of the causes and development of diseases within equine populations. It encompasses various factors, including genetic predisposition, environmental influences, infectious agents, and nutritional imbalances, that contribute to the onset and progression of diseases in horses. Understanding disease etiology is essential for identifying risk factors and implementing preventative measures in equine health management. This topic includes research on pathogen-host interactions, the impact of management practices on disease incidence, and the role of genetic and environmental factors in disease susceptibility. This page compiles peer-reviewed research studies and scholarly articles that explore the mechanisms, contributing factors, and implications of disease etiology in horses.
Geisel O, von Sandersleben J.The chronic obstructive pulmonary disease (COPD) in horses is primarily based on a chronic bronchitis/bronchiolitis with constriction of the tubes in the lower respiratory tract. The outward appearance of the lung is characterized by a diffuse or marginal alveolar emphysema. The big bronchial tubes are usually not altered. Small bronchi and bronchioli can often be seen through the pulmonal pleura. On the sectional area they are visible as opaque grey-red nodules with a central lumen detectable under a magnifying glass. The histopathological picture of alterations in the bronchial tree can vary...
Poss M, Young S.A 4-year-old horse was evaluated at the Colorado State University Veterinary Teaching Hospital for rapidly progressing cerebellar disease. Euthanasia was elected and at postmortem examination a proliferative mass encompassing the right side of the cerebellum was discovered. The lesion was characterized by large, convoluted, vascular folia and absence of the core of central white matter. Histologically, there was a diminution or loss of the internal granule cell layer, cavitation of the central white matter, and absence of Purkinje cells. The molecular layer was thickened with myelinated axons ...
Leidl W, Kaspar B, Kähn W.Endometrial cysts were found in 11 (13.4%) of 82 mares of various breeds by clinical examinations. Endometrial cysts were diagnosed by hysteroscopy and ultrasonic echography. Typical images are described. The importance of endometrial cysts is discussed with regard to differential diagnosis of early pregnancy and uterine pathology. There was no evidence of cysts in mares under 10 years of age. Mares with endometrial cysts had a 10% higher history of disturbed fertility than mares without endometrial cysts. Seven of nine mares with cystic structures in the uterus became pregnant. Endometrial cy...
Mumford JA, Rossdale PD, Jessett DM, Gann SJ, Ousey J, Cook RF.An extensive outbreak of EHV-1 abortions occurred on a stud farm in England in 1985. Of the 67 pregnant mares present on the stud farm, 31 were challenged with EHV-1, resulting in the loss of 22 fetuses or foals. Laboratory investigations revealed that the spread of the virus closely followed movement of apparently healthy mares (during the incubation period of the infection). During the outbreak mares were challenged 1-4 months before the expected foaling date. There was no relationship between the gestational age at the time of challenge and the subsequent outcome of infection in terms of ab...
Ziemer EL, Whitlock RH, Palmer JE, Spencer PA.The clinical and hematologic variables of 10 ponies with experimentally induced equine ehrlichial colitis (EEC; syn: Potomac horse fever) were studied for a 30-day period (6 ponies) or until death (4 ponies). The earliest clinical sign indicative of EEC was fever (rectal temperature exceeding 39 C). All ponies became depressed (CNS) at various times during the disease, and 90% of the ponies developed diarrhea between 9 and 15 days after infection was induced. The most significant hematologic change was an increase in plasma protein concentration after the onset of fever (P less than 0.05). The...
Duncan ID, Schneider RK, Hammang JP.The suprascapular nerve from 14 horses, which had no clinical evidence of spinatus muscle atrophy, were obtained to determine whether the nerve was sub-clinically compressed at the scapular edge. The nerves were divided into three portions, proximal and distal to the scapular edge and as it reflected around it. In nine horses there was evidence of a chronic neuropathy which varied in severity and which was most severe at the site of reflection, where the nerve appeared constricted by a tendinous band. At this site the predominant change was that of chronic demyelination and remyelination, with...
Vandeplassche MM.From a total of 601 severe dystocias in mares, 408 (68%) of the fetuses were in anterior, 95 (16%) in posterior and 98 (16%) in transverse presentation, compared with 99%, 1% and 0.1% respectively for spontaneous parturitions. From the cases with anterior presentation, 151 (37%) showed reflected heads and necks. From the cases with posterior presentation, 47 (50%) presented hip flexions, 25% had hock flexions, and 25% had stretched hind legs, 45 (47%) of the fetuses were in lateral or ventral position, and 28 (30%) of the fetuses were malformed (mainly torticollis and head scoliosis). All 98 c...
Meijler FL, van der Tweel I.Atrial fibrillation is one of the most common cardiac arrhythmias in humans. It also occurs quite frequently in dogs and horses. Comparative study of this arrhythmia may contribute to better understanding of the pathophysiological mechanisms involved. In this study, we present a quantitative analysis of atrial fibrillation in humans, dogs, horses, and in a kangaroo, making use of histograms and serial autocorrelograms of the ventricular rhythm with and without digitalis medication. Increase in the size of the animal and thus in the size of the heart is accompanied by a decrease in ventricular ...
Eichhorn W.Infections and clinical diseases caused by equine 2 influenza A viruses are observed worldwide. The frequency of these outbreaks supports the hypothesis that antigenic variation of the surface proteins may play an important role. For the demonstration of these variations, monoclonal antibodies (Mabs) were prepared. They are directed against the hemagglutinin or the neuraminidase of the prototype strain a/eq/Miami/1/63. In hemagglutination-inhibition assays with Mabs two reaction patterns were observed: four Mabs inhibited 14 out of 17 strains tested. Another Mab recognized the hemagglutinin of...
Reif JS, Webb PA, Monath TP, Emerson JK, Poland JD, Kemp GE, Cholas G.In 1982-1983, an epizootic of vesicular stomatitis occurred in the western United States. Veterinarians, research workers, and regulatory personnel who were exposed to vesicular stomatitis virus were examined for patterns of human infection and prevalence of vesicular stomatitis New Jersey serotype neutralizing antibody. Insight into the mechanism of transmission was sought by comparing activities of antibody-positive and antibody-negative persons. A statistically significant risk factor was a history of infected animals sneezing in the face of serosurvey participants. Elevated odds ratios wer...
Lane JG, Lucke VM, Wright AI.Papillomatous lesions intruding into the laryngeal airway were identified in an imported polo pony during a routine neurological examination for partial quadriplegia. Histological examination established a diagnosis of laryngeal besnoitiosis but it is unlikely that the laryngeal parasitism was associated with the cerebellar neuropathy which was also present.
Beaver BV.Accurate diagnosis of the cause of aggression in horses is essential to determining the appropriate course of action. The affective forms of aggression include fear-induced, pain-induced, intermale, dominance, protective, maternal, learned, and redirected aggressions. Non-affective aggression includes play and sex-related forms. Irritable aggression and hypertestosteronism in mares are medical problems, whereas genetic factors, brain dysfunction, and self-mutilation are also concerns.
Crowell-Davis SL, Houpt KA.Parturition in mares is rapid and is followed by a brief period of sensitivity to imprinting on a foal. There is large individual variation in normal maternal style, but normal mothers actively defend their foal, remain near the foal when it is sleeping, tolerate or assist nursing, and do not injure their own foal. Disturbance of a mare and foal during the early imprinting period can predispose a mare to rejection of her foal; therefore, it should be avoided. There are a variety of forms of foal rejection and numerous etiologies. Therefore, each case should be evaluated individually.
Liu IK, Cheung AT, Walsh EM, Ayin S.The functional competence of uterine-derived polymorphonuclear neutrophils (PMNs) from 28 mares was measured for migration responsiveness by use of a chamber (filter) assay. Uterine infection was induced with Streptococcus zooepidemicus in mares considered resistant to chronic uterine infection (Grade I). In sequential analysis of uterine flushings obtained from these mares 5, 12, 15, 20, and 25 h after infection was induced, PMNs showed an initial rise at 12 h (from 5), then a general decline in migration response and in concentration of cells per ml from 12 through 25 h post-inoculation. In ...
Crowell-Davis SL, Houpt KA.A thorough behavioral history is essential for adequate assessment of a given case. In reviewing the chief complaint, a description of what actually happened, rather than the owner's interpretation of what happened, is required. Other behavior problems, environment, rearing history, and training need to be reviewed. Sample question sets for some common problems are given.
Adeyefa CA.The effects of the various growth factors with regard to the nutritional physiology of zoophilic dermatophytes isolated from horses are reported. The optimum temperature, pH and growth period for the fungal isolates were found to be 30 degrees-35 degrees C, 5-6 and 7-12 days respectively while the carbon and nitrogen sources utilised by the organisms were sucrose, fructose, maltose, L-arginine and calcium nitrate. The use of these factors in preparation of efficacious fungicides used in the treatment of ringworm infections in man and animals is discussed.
Rushlow K, Olsen K, Stiegler G, Payne SL, Montelaro RC, Issel CJ.The nucleotide sequence of the envelope (env) gene region of equine infectious anemia virus (EIAV), a member of the lentivirus subfamily of retroviruses, has been determined from a clone of integrated proviral DNA for which the gag and pol sequences have been reported previously. The env gene is 859 codons in length and the sequence reported here is consistent with the published biochemical properties of EIAV glycoproteins. The env gene region of EIAV shares considerable structural similarities but negligible sequence homologies with the env genes of other members of the lentivirus subfamily, ...
Burgess EC, Gillette D, Pickett JP.Infection with Borrelia burgdorferi caused panuveitis and arthritis in a pony. Spirochetes were detected by direct immunofluorescence in the anterior chamber of the eye. The carpal joints had severe degenerative joint disease, with synovial proliferation. The synovium and serum had B burgdorferi antibody titers of 1:1024. The pony lived in an area of Wisconsin where infection with B burgdorferi is endemic in human beings. Previously, serum antibodies to B burgdorferi had been found in horses, but disease had not been reported.
Cahill JI, Goulden BE.This study confirmed that neurogenic muscle pathology exists in intrinsic laryngeal muscles supplied by the recurrent laryngeal nerves in horses subclinically and clinically affected with laryngeal hemiplegia. An important additional observation was the occurrence in three out of four laryngeal hemiplegic horses of neurogenic muscle changes in a hindlimb muscle, the extensor digitorum longus, a muscle supplied by another long peripheral nerve. This finding suggests that a polynenropathy exists in laryngeal hemiplegic horses, and supports the classification of this disease as a distal axonopath...
Schmidtmann ET, Robl MG, Carroll JF.The capability of field-collected American dog ticks, Dermacentor variabilis, to infect horses with Ehrlichia risticii, causative agent of Potomac horse fever (PHF), was examined by allowing adult ticks collected from horse farms with a history of PHF to feed on susceptible horses. More than 500 male and female ticks attached and fed on 3 test horses; however, no clinical or serologic evidence of PHF was observed in treated or control horses. All horses were challenge exposed with E risticii-infective blood by inoculation at 60 to 65 days after ticks fed, and all developed clinical PHF with su...
Schneider J, Kaaden O, Copeland TD, Oroszlan S, Hunsmann G.Two glycopolypeptides with molecular weights 160,000 and 120,000 (gp120) are regularly recognized by human immunodeficiency virus (HIV)-specific antisera in lysates of cells persistently infected with HIV. In the present study, gp120 was characterized as the major envelope glycopolypeptide of HIV. Gp120 was identified as the external viral glycoprotein by radiosequencing and by its presence in purified virus. However gp120 was predominantly shed as a soluble protein into the culture fluid. Furthermore gp120 was precipitated by sera from horses infected with equine infectious anaemia virus (EIA...
Buergelt CD, Hines SA, Cantor G, Stirk A, Wilson JH.Proliferative and fibrosing interstitial lung disease was diagnosed in 20 horses submitted for necropsy between 1982 and 1985. Most of the horses were foals ranging from 3 days to 6 months in age. Six adult horses were affected. The macroscopic and microscopic characteristics of the lesions consisted of proliferative interstitial pneumonia and were similar to those of atypical interstitial pneumonia of ruminants. Based on morphologic features of the lesions, a toxic etiology is suspected for the induction of this naturally acquired primary equine lung disorder, but could not be specifically di...
Hosie BD, Gould PW, Hunter AR, Low JC, Munro R, Wilson HC.A myopathy of horses at grass in east and south east Scotland was recognised in the autumn and winter of 1984 and the spring of 1985. The clinical signs resembled those of paralytic myoglobinuria. Grossly increased creatine kinase activities and the passage of dark brown urine were consistent features. However, the horses were not in training, most of them died and the muscles affected were those of posture and respiration rather than movement. The condition may be unrelated to nutritional myopathy because all the cases had adequate levels of alpha-tocopherol although their selenium status var...
Herd RP.Seasonal rises in mean faecal egg output were observed in grazing ponies in spring (578 eggs per gram) and in summer (930 epg) on 30 April and 2 September, respectively, in untreated ponies. Pasture infectivity reached a peak of 18,486 third stage larvae (L3)/kg on 17 September, two weeks after peak egg counts, coincidental with abundant September rainfall (103.0 mm). Differentiation of infective larvae from pasture showed the cyathostomes (small strongyles) to be predominant, but Trichostrongylus axei assumed major importance from late August to October. The large strongyles were rarely detec...
Cahill JI, Goulden BE.Individual nerve fibres were isolated from the recurrent laryngeal and some distal hindlimb nerves, in an investigation of equine laryngeal hemiplegia. One hundred teased fibres were obtained from each of three sampling sites on both left and right recurrent laryngeal nerves, from 15 Thoroughbred horses. These fibres were graded descriptively and internode lengths measured. A distal distribution of pathology was demonstrated in all groups studied, but was most severe in the clinical group of horses. The predominant change was one of short thinly myelinated internodes interspersed amongst norma...
Platt D, Wright IM.The history, clinical features, radiological findings, treatment and outcome of 15 horses with chronic tenosynovitis of the carpal extensor tendon sheaths are reported. The condition was seen most commonly in horses used for jumping and penetration of the tendon sheaths by thorns was the most common aetiology. Treatment involved surgical resection of the hyperplastic synovial membrane, and adhesions within the tendon sheath, with primary closure. When combined with early postoperative physiotherapy this was found to be an effective method of treatment. All horses in this series were not lame a...
Kondo T, Sato F, Tsuzuki N, Yamada K.Cervical vertebral stenotic myelopathy (CVSM), a common cause of cervical spinal cord compression, is a neurological disease characterized by general proprioceptive ataxia and weakness of hindlimbs that tends to develop in young adult Thoroughbred horses. Although male horses seem to be at increased risk for CVSM, the mechanism for the occurrence of sex differences in the prevalence of CVSM is still poorly understood. Hence, we hypothesized that sex differences in the development of cervical spinal cord and spinal canal would affect the development of CVSM. This study aimed to evaluate sex dif...
Sahu SP, Pierson RE, Dardiri AH.Actively growing culture of contagious equine metritis (CEM) bacteria or infective exudate (or both) were inoculated intrauterine in pony mares. A direct relationship was observed between (i) appearance and duration of cervicitis and vaginitis and (ii) vaginal exudate. Clinical signs appeared 1 to 3 days after mares were inoculated and lasted 7 to 23 days. In the acute phase of infection, all uterine and cervical samples yielded CEM bacteria. In the asymptomatic stage of infection, CEM bacteria were not isolated from uterine and cervical samples; however, in 33%, 28%, and 20% of the pony mares...
Allen GK, Green EM, Robinson JA, Garner HE, Loch WE, Walsh DM.We examined the effect of infusion of lipopolysaccharide (LPS) on serum tumor necrosis factor alpha (TNF alpha) concentration and clinical attitude in 2- 3-day-old colostrum-fed (CF) and colostrum-deprived (CD) foals. Eleven CF and 8 CD neonatal foals were given a bolus i.v. infusion of Escherichia coli O55:B5 lipopolysaccharide (0.5 microgram/kg of body weight) in sterile saline (0.9% NaCl) solution. Four CF and 2 CD foals were given saline solution alone. Serum IgG concentration and serum anti-LPS IgG(T) antibody titer were determined for each foal prior to infusion. A depression index was u...
Rungsipipat A, Tateyama S, Yamaguchi R, Uchida K, Miyoshi N.An immunohistochemical study of various visceral organs of normal adult dogs, cats, pigs, horses, cows, and chickens (five of each species) and of 185 spontaneous canine tumours was carried out using paraffin wax sections and a commercially available antibody to the human c- yes oncogene product. Among the adult normal tissues of six animal species, epithelial cells of the proximal and distal renal tubules, the myocardium, hepatocytes, cerebellar Purkinje cells and adrenal cortical cells were positive for c- yes product. Among the foetal tissues of dogs and chickens, a positive reaction was ob...
Acevedo HD, Hassebroek AM, Leventhal HR, Duhamel GE, Carvallo FR.A 17-y-old Rocky Mountain gelding was presented to the Virginia-Maryland Veterinary Teaching Hospital because of a 4-wk history of anorexia, weight loss, lethargy, and fever of unknown origin. Abdominal ultrasound revealed lymphadenomegaly of the abdominal and colonic lymph nodes, thickening of the wall of the large colon, and a mass associated with the large colon. The horse was euthanized given a poor prognosis. On autopsy, an ~20-cm diameter mass was found within the mesocolon between the right ventral and right dorsal colon. The mass had invaded through the colonic walls and formed a fistu...
Coté N, Trout DR, Hayes MA.Binding between equine plasma alpha-2-macroglobulin (alpha 2M) and several cytokines known to participate in inflammatory reactions in other species was initially examined. Plasma was obtained from 5 horses with various abnormalities. Samples, both untreated and after reaction with methylamine, were incubated with exogenous, radiolabeled, porcine-derived transforming growth factor-beta-1 (125I-TGF-beta 1), recombinant human interleukin-1-beta (125I-IL-1 beta), and recombinant human tumor necrosis factor-alpha (125I-rhTNF-alpha). They were then subjected to nondenaturing polyacrylamide gel elec...
O'Sullivan BM, Goodwin JA.On 6 properties in south-western Queensland an outbreak of nervous disease occurred horses due to ingestion of Swainsonia (Darling pea). Loss of condition, depression, hyperaesthesia and hyperexcitability were seen in affected horses. At autopsy of 2 horses generalised c ytoplasmic vacuolation was seen in the neurones of the central nervous system and in the liver, adrenal and thyroid. The clinical and pathological features were similar to those described in horses suffering from Swainsona poisoning in Australia and Astragalus and Oxytropis in North America.
Goetz TE, Coffman JR.Ulcerative colitis, protein losing enteropathy and intestinal histoplasmosis-salmonellosis were diagnosed in a six-year-old Quarterhorse stallion. For six months before examination, the horse experienced a slow continual loss of weight. During the 17 day period of hospitalisation the horse developed progressive generalised oedema. On the 12th day of hospitalisation a severe profuse watery diarrhoea began; the horse was killed five days later.
Howden KJ.A Thoroughbred mare was presented for stallion-like behavior. Reproductive and ultrasonographic evaluation, testosterone assays, and karyotyping confirmed a diagnosis of androgen insensitivity syndrome (64, XY--testicular feminization). Surgery to remove abdominal testicles was successful in alleviating the behavioral abnormality. This condition is discussed with reference to the current literature. Une jument Thoroughbred a été présentée parce qu’elle avait un comportement d’étalon. Une évaluation reproductrice et échographique, des dosages de testostérone et un caryotypage ont c...
Büsing K, Mietke-Hofmann H, Dibbert R, Donandt D, Maier T, Zeyner A.A new batch of a supplemental feed was fed as pellets (diameter 8 mm) to two Warmblood-type horses. One horse developed watery diarrhoea within two days. Pronounced oedema due to hypalbuminemia was seen about ten days later. The feed was replaced by pellets of identical composition and mixing process, but lower diameter (5 mm). After one week of feeding, oedema regressed and faeces were normally formed. At refeeding the larger sized pellets, the symptoms recurred, but now both horses were affected. After a change to the smaller pellets, the horses recovered soon. Water activity (aw-value) of t...
Lemirre T, Santschi EM, Girard CA, Fogarty U, Janes JG, Richard H, Laverty S.The aetiology of equine medial femoral condyle (MFC) subchondral bone radiolucencies (SR) is unknown. Objective: Characterise the microstructural structural features of MFC SR in juvenile Thoroughbreds with microcomputed tomography (μCT) and histology. Methods: Cross-sectional post-mortem study. Methods: Distal femurs were collected at post-mortem. Conventional tomodensitometry was employed to scout for MFCs with and without SR lesions (SR+ and SR-, respectively). Group 1 were CT MFC SR+ and Group 2 age-matched SR- controls. Both underwent μCT and histological analysis. Group 3 CT MFC SR- fo...
Littlejohn A, Bowles F.Pressure curves obtained by cardiac catheterization of the pulmonary artery, right ventricle and right atrium of 9 horses and ponies with chronic obstructive pulmonary disease (COPD) were compared with those similarly recorded from 6 clinically normal control subjects. The mean pulmonary peak systolic, pulmonary minimum diastolic and ventricular peak systolic pressures of the COPD subjects were significantly higher (P less than 0,01) than the corresponding mean pressures of the clinically normal control subjects. The mean pressure calculated from pressure curves obtained from 8 Thoroughbreds i...
Fidani M, Pompa G, Mungiguerra F, Casati A, Fracchiolla ML, Arioli F.After the detection of low concentrations of prednisolone in racehorse urine samples collected at Italian racetracks, a study was initiated to investigate the accuracy of the analytical protocol used and the possible endogenous origin of detected prednisolone. Methods: Multiple reaction monitoring (MRM) MS(2) acquisition with a triple quadrupole (n = 780) and full scan MS(2) and MS(3) (n = 180) acquisition with a linear ion trap were checked. As a further confirmation, ten urine samples were analysed by high-resolution mass spectrometry (HRMS). Results: The study showed the difficulty of ident...
Hann MJ, Mair TS, Gardner A, Mudge M, Southwood LL, Dechant JE, Barton MH, Garcia-Macias J, Parker RA, Hassel D, Archer DC.Incisional complications are a common cause of morbidity following laparotomy. Although uncommon, acute abdominal dehiscence (AAD) is a potentially fatal post-operative complication. However, few AAD cases are described in the literature. Objective: To describe common features of cases of AAD following ventral midline laparotomy, management and outcomes. Methods: Retrospective case series. Methods: Hospital records of horses that underwent a ventral midline laparotomy at nine hospitals in the UK, Ireland and USA over a 10-year period (2009-2019) were reviewed. Data were collected for pre-, int...
Walton TE, Holbrook FR, Bolivar-Raya R, Ferrer-Romero J, Ortega MD.The arthropod-borne virus (arbovirus) diseases of livestock have worldwide impact. The prevention of an introduction of an exotic disease and the control of one subsequent to an introduction will require the attention, cooperation, and support of the livestock industry, regulatory agencies, and researchers. The most effective protection of our livestock industries is to prevent the introduction of an exotic disease agent. This implies complete restriction of animal imports and exports. However, "zero risk" is an unacceptable option in today's world of internationally integrated and interdepend...
Szabó MP, Castagnolli KC, Santana DA, de Castro MB, Romano MA.Since host immune reaction to ticks interferes with tick-borne pathogen transmission, it is important to recognize naturally occurring tick-host immune relationships to better understand the epidemiology of such infectious diseases. Amblyomma cajennense is an important tick-borne disease vector in the Neotropical region and horses maintain it in domestic environments. In the present work intradermal testing of A. cajennense tick exposed horses and donkeys using crude tick antigens was used to evaluate the type of hypersensitivity induced by infestations. Animals sensitized by A. cajennense inf...
Alemayehu MT, Abebe BK, Haile SM.Horses are used for a variety of purposes in Ethiopia. However, their service is hampered by a variety of health issues. Strongylosis is a parasitic infestation of the gastrointestinal tract that has a significant impact on the working ability, reproductive performance, well-being, and welfare of horses. The existence of Strongylosis in the study area is reported from clinical cases; however, its prevalence has not been well studied. Unassigned: The current study was carried out from January 2019 to July 2019, to determine the prevalence and associated risk factors of Strongyle in horses in an...
Garma-Aviña A.A total of 100 samples of abdominal fluid (AF) from 100 horses with abdominal disease were evaluated by cytology. Cytology results were subsequently correlated with the final outcome of the disease. The horses were classified into 4 groups: Group I, horses that were treated with conventional (nonsurgical) therapy and recovered; Group II, horses that had surgery and survived; Group III, horses that had surgery but died; and Group IV, horses that were subjected to euthanasia prior to surgery. Statistical analysis showed that both nucleated cell count and total neutrophils were significantly high...
Hance SR, Robertson JT, Bukowiecki CF.Two horses were examined for compression of the pharynx from the dorsal pharyngeal wall. Neither horse had a patent opening of 1 of the guttural pouches. Radiography of the guttural pouch region revealed a retropharyngeal opacity that occluded 1 guttural pouch. Organisms were not isolated on bacteriologic culture of fluid obtained from the affected guttural pouch. Surgical exploration of the guttural pouch revealed the lining to be easily removeable by blunt dissection in 1 horse; however, the lining was more firmly attached and removal was not attempted in the second horse. A fenestration bet...
Drudge JH, Lyons ET, Tolliver SC, Fallon EH.Clinical trials on a central Kentucky Thoroughbred Farm (B) during 1960-1961 involved nine test treatments of mares, yearlings and weanlings (n = 124), and compared efficacies of phenothiazine (PTZ), piperazine (PPZ), mixtures of PTZ + PPZ and thiabendazole (TBZ) for (1) percent reduction and (2) complete clearance or graded reduction of strongyle egg per gram (epg) counts. Three grades of PTZ (N.F. green, micronized purified and 2-3 microns purified) at the dose rate of 55 mg kg-1 were ineffective in six tests; reduction of strongyle epg count were low grade (26%) and complete clearance was f...
Niwa H, Higuchi T, Fujii S, Kinoshita Y, Uchida-Fujii E, Sueyoshi M, Nukada T, Ueno T.Equine proliferative enteropathy (EPE) is an equine infectious disease that can lead to severe weight loss and hyperplasia of the intestinal mucosa due to infection with Lawsonia intracellularis. In this study, we investigated the prevalence of EPE in a major Thoroughbred breeding area: Hidaka district, Hokkaido, Japan. Of the 252 symptomatic horses that we tested, 192 EPE cases (76.2%), including 8 fatal cases, were confirmed from April 2015 to March 2020 by etiological and/or serological investigation. Most of the EPE cases were observed in foals (88.5%), with fewer cases in yearlings (7.3%)...
Peixoto Rabelo I, Barroco de Paula V, Carvalho Bustamante C, Santana AM, Gomes da Silva D, Baldassi AC, Canola PA, Araújo Valadão CA.Horses submitted to carbohydrate overload can develop laminitis due to changes in cecal pH and microbiota, followed by an increase in transmural absorption of luminal content, including bacterial toxins. In response to acute injury there is hepatic overproduction of several proteins known as acute phase proteins (APP). Few studies have evaluated protein fractionation to characterize the inflammatory response in acute laminitis. The aim of this study was to test the viability of an experimental model to induce acute laminitis, using a single carbohydrate overload, and the influence of a bufferi...
Pratt SL, Bowen M, Hallowell GH, Shipman E, Bailey J, Redpath A.Equine glandular gastric disease (EGGD) is a common condition of the horse. Misoprostol is reported to be superior to oral omeprazole and sucralfate for treatment. Long-acting intramuscular injectable omeprazole (LAIOMEP) is a novel treatment shown to be effective in a small population. This study aimed to determine LAIOMEP efficacy compared to misoprostol and oral omeprazole and identify characteristics that predict treatment outcome. All horses that underwent gastroscopy between 2012 and 2019 were reviewed. Lesions were characterised by 4 blinded observers, all of whom are diplomates in equi...
Badial PR, Teixeira RBC, Delfiol DJZ, da Mota LSLS, Borges AS.Overo lethal white foal syndrome (OLWFS) is a genetic disorder caused by a dinucleotide mutation in the endothelin receptor type B (EDNRB) gene leading to the death of affected foals shortly after birth. The use of rapid and reliable genetic testing is imperative for the early diagnosis of the mutation avoiding, therefore, either additional suffering or the production of affected animals. In the present study, we developed and validated a high-resolution melting (HRM) genotyping assay to detect the OLWFS causative mutation, and we also determined the frequency of heterozygotes among American P...
Griffiths IR, Smith S, Doxey DL, Whitwell K, Love S.Sera from acute and chronic cases of natural grass sickness or normal horses were injected into the parotid salivary gland of ponies. This gland receives its sympathetic innervation from the ipsilateral cranial cervical ganglion. None of the ponies showed any local or systemic signs of illness. After one week the cranial cervical ganglia, stellate and coeliaco-mesenteric ganglia were removed for histological study. Pathological changes were found only in the cranial cervical ganglion ipsilateral to a parotid salivary gland which had received an injection of grass sickness serum. Four out of fi...
Lejeune JP, Schneider N, Caudron I, Duvivier DH, Serteyn D.Ossification of collateral cartilages is a common radiographic finding in draught horses and indication of a high frequency of interphalangeal osteo-arthropathy have been found in Ardenner horses. This study first aimed at following the evolution of the digits of the forelimbs on radiographic images in a group of 32 Ardenner horses from weaning to 852 +/- 19 days and, secondly, at evaluating the clinical significance of the observed radiographic changes. At 250 +/- 21 days, only 23% of the horses presented a small separate ossification centre of collateral cartilages above the level of the dis...
Lindberg R, Karlsson L.The jejunal mucosa of 4 cases of equine granulomatous enteritis and 2 control horses was investigated by light microscopy and by scanning and transmission electron microscopy. Attention was focused upon changes in mucosal topography and enterocyte morphology in the inflamed mucosa. Structural changes ranged in severity from only a slight thickening and shortening of villi to the appearance of a virtually flat mucosa, upon which crypts opened directly or through shallow cavities encircled by collars of epithelial cells. Between these extremes, the mucosa showed a variety of patterns, all charac...
Goto Asakawa M, Mehmood W, Ali M, Oikawa MA.Myocardial atrophy with fibrosis and fatty infiltration involving the cardiac conduction system is relatively unusual in horses. We herein report of such a case in a 13-year-old Arabian broodmare that had spontaneously died on a paddock. An autopsy revealed multifocal myocardial atrophy with concomitant fibrosis and fatty infiltration in both the ventricles and interventricular septum. The Purkinje fibres in the ventricles and interventricular septum were surrounded by thick fibrous or adipose tissues adjacent to atrophic myocardial cells. Myocardial fibrosis and fatty infiltration were likely...
Brito G, Damián JP, Suárez G, Ruprechter G, Trigo P.RHU is the oldest endurance sport in Uruguay. However, despite 80 years of racing, there are no studies to characterize this type of competition, explore rates and causes of death, and identify the associated risk factors. The aim was to characterize the Raid Hipico Uruguayo (RHU) competencies according to the distance (short (SR, 60 km) vs. long (LR, 80-115 km)), the causes of deaths, and the associated risk factors. The study population comprised horses ( = 16,856) that participated in RHU rides from 2007 to 2018. LR were more frequent than SR ( < 0.001). The average speed of winners was ...
