Autopsy in horses involves the systematic examination of a deceased horse to determine the cause of death and to study any disease or injury that may have been present. This process, also known as necropsy, is performed by veterinary pathologists and involves a thorough inspection of the horse's body, including external and internal organs. During an autopsy, tissue samples may be collected for histopathological analysis to identify any microscopic abnormalities. The findings from an autopsy can provide valuable insights into equine health issues, contributing to the understanding of disease processes, informing treatment strategies, and improving management practices. This page compiles peer-reviewed research studies and scholarly articles that explore the methodologies, findings, and implications of autopsy in equine veterinary science.
Azari O, Ghamsari SM, Roustaei A, Golchin D, Baharloo F, Javaheri M, Valizadeh N.This report describes a case of massive renal cell carcinoma (RCC) causing mild chronic colic in a 20-day-postpartum Arabian mare. The mare presented with deteriorating abdominal pain following normal parturition. Clinical examination revealed tachycardia, tachypnoea, weak intestinal motility and pale mucosal membranes. Rectal examination identified a very large mass in the caudal part of the abdominal cavity, and abdominal ultrasound examination revealed a huge space-occupying mass with renal architecture. During midline exploratory laparotomy, a massive tumour was observed in the anatomical ...
Morgan J, Curtis Shaw G, Weisman J, Cecere T, Carvallo-Chaigneau FR.A 2-d-old Warmblood colt was submitted for autopsy with a spectrum of bilateral ocular abnormalities. At postmortem examination, a constellation of lesions within the anterior segment included retention of ectodermal elements, compatible with choristoma. Ocular choristomas can be localized to different intraocular structures and are rare in equids. The morphologic features in our case were suggestive of abnormal corneal differentiation.
Primo ALM, Assis DM, Santos VGS, de Melo LRB, da Nóbrega LD, Medeiros Dantas AF, Maciel TA.Cerebellar abiotrophy is a neurodegenerative disease that affects the Purkinje cells of the cerebellum, resulting in premature neuronal death. In horses, its occurrence has been reported mainly in the Arabian breed as a congenital mutation inherited in an autosomal recessive manner. The objective of this study was to describe the case of cerebellar abiotrophy in a Quarter Horse foal. An 8-day-old foal was treated after presenting signs of ataxia, hypermetria, difficulty maintaining a standing position, and decreased menace response. The foal was hospitalized for 26 days, received treatment wit...
Medina-Bolívar AL, Faleiros RR, Martínez-Aranzales JR.Limited information is available on gastric diseases in neonatal foals as compared with extensive studies in young, adult, and geriatric horses. Reports on fetuses are scarce. Objective: Assess at necropsy stomachs of horse, donkey and mule fetuses in the third trimester of gestation to characterize lesions present during intrauterine life. Methods: Forty-six fetal stomachs from both sexes (21 horses, 21 donkeys, and 4 mules) in the third trimester of gestation were collected from a processing plant immediately after slaughter. Methods: Measurements of longitudinal and transverse axes, weight ...
Peretti JC, Dos Santos AB, Davi Dos Santos E, Machado TP, Pescador CA, Quillas LJA, Milani VM, Picetti TS, da Motta AC.Lymphoma is the most common tumor of hematopoietic origin in horses. The course of the disease and clinical signs vary greatly, depending on tumor location and extent. The aim of this report is to describe the occurrence of T-cell-rich oral large B-cell lymphoma with marked local infiltration in a 25-year-old Crioula mare. The mare showed an increase in volume on the right side of its face, dyspnea, anorexia, and progressive weight loss. The clinical assessment showed that the lesion was located in the rostral and caudal sinuses and was markedly invasive to adjacent structures. The autopsy rev...
Inglis ZE, Firshman AM, Lochner HL, Martinson KL.In recent years, the number of horses submitted for necropsy has been in decline. This study aimed to identify the perceptions and barriers of equine necropsy through an online survey of horse owners. The data were analyzed by multivariate models for associations and factors that influenced decision making regarding necropsy. The survey yielded 1,366 usable responses. Respondents had higher familiarity with the term "autopsy" compared to "necropsy" (P<0.001) and showed a greater level of comfort using the terms "body" and "mortality" compared to "carcass" (P<0.001). Most respondents (82%) had ...
Schinköthe J, Gerlach K, Ulrich RG, Brehm W.A 12-y-old Shetland Pony was presented with a mucus-secreting fistula in the right paralumbar fossa. Surgery was performed to unravel the origin of the fistula. The horse died under anesthesia and was forwarded to autopsy. The right kidney was markedly atrophic and fibrotic, consistent with unilateral end-stage kidney. The right ureter was markedly thickened, but with luminal continuity leading into the urinary bladder where a partial obstruction caused by nodular para-ureteral fat necrosis was evident. The lumen of the cutaneous fistula was continuous with the right ureter; therefore, we diag...
Metcalfe A, Craig LE.This retrospective study describes 8 cases of intestinal hemangioma diagnosed in horses during postmortem examination or surgical biopsy at the University of Tennessee College of Veterinary Medicine. In all cases, the intestine was the sole organ affected, and lesions were focal (3/8) or multifocal (5/8). Nodules were most commonly within the small intestine (7/8), particularly the jejunum (5/7). One case was in the left dorsal colon, which is the first report of hemangioma in the large colon of a horse. Lesions were discrete, raised, smooth, black to red, and ranged from 2 to 15 mm in diamete...
Barton CK, Hughes KL, Cowan C, Nout-Lomas YS, Nelson BB.A 21-year-old Quarter Horse mare presented with a chronic, progressively worsening left pelvic limb lameness of 3 weeks duration. The initial examination identified a consistent lameness at a walk. Neurological examination showed sensory and gait abnormalities consistent with left femoral nerve dysfunction. The horse minimally advanced the leg cranially and had a shortened stride length at the walk. During the stance phase, the heels of the left hind foot did not contact the ground and the horse quickly took weight off of the limb. Diagnostic imaging (ultrasound and nuclear scintigraphy) exami...
Zhanabayev A, Ibrayev B, Lider L, Ussenbayev A, Bissengaliyev R.The research relevance is predefined by the widespread distribution of parasitosis, including helminthiases, alongside constant depasture on the same areas of pastures, which annually causes massive re‑infection of horses. In this regard, the research aims to identify the age, seasonal, and territorial dynamics of infection of horses with helminthiases in the context of the districts of the northern region of Kazakhstan. The primary research method was an experimental analysis that allowing to consider the dynamics and causes of horse helminthiases, associated with the prepatent period, the ...
Rissi DR, Avery AC, Burnett RC.T-cell-rich, large B-cell lymphoma (TCRLBCL) is the most commonly diagnosed type of lymphoma in horses. Here we describe the clinical signs, neuropathology, immunohistochemistry (IHC), and PCR for antigen receptor rearrangement (PARR) analysis results of a TCRLBCL in the brain of an 8-y-old male Quarter Horse that was euthanized after acute anorexia, tremors, head pressing, falling, blindness, incoordination, and seizures. Autopsy revealed a firm, smooth, pale-yellow mass that expanded both lateral ventricles and the adjacent subcortical white matter. Histologically, the mass consisted of a de...
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...
Ludwig EK, Hallowell K, Womble M, O'Neil E.A 2-day-old Cleveland Bay colt was referred to the Equine Emergency Service of the Farm Animal and Equine Veterinary Medical Center at North Carolina State University's College of Veterinary Medicine for evaluation of decreased nursing behaviour and right hindlimb lameness of 2 days' duration. When assisted to stand, the foal was unable to extend either hindlimb or bear weight on the hindlimbs, the right patella was luxated laterally and unable to be reduced, and the foal assumed a crouched position. Stifle radiographs revealed minimal, heterogeneous, ill-defined ossification of both patellae....
Nissen SD, Saljic A, Kjeldsen ST, Jespersen T, Hopster-Iversen C, Buhl R.Second-degree atrioventricular (AV) block is the most common cardiac arrhythmia in horses, affecting 40-90% depending on breed. Usually, the AV blocks occur while the horses are resting and disappear upon exercise and are, therefore, considered to be uneventful for horses. However, if the AV blocks occur frequently, this may result in syncope and collapse. Identifying the cause of second-degree AV block is difficult and often subscribed to high vagal tone. In this report, we present an eight-year-old Quarter horse with a high burden of second-degree AV blocks and multiple collapses. The clinic...
A Quarter Horse, a gelding aged 22, was subjected to a clinical examination for colic syndrome. During admission to the clinic, blood counts and ultrasound examination were performed. Ultrasound revealed abdominal masses and abundant accumulation of pleural (50 L) and abdominal fluid (100 L). Cytology was performed on the aspirated fluid. The patient was euthanized. The autopsy examination revealed abundant effusion and nodular masses on the peritoneum, omentum, lungs, heart, and mediastinum. A diagnosis of epithelioid mesothelioma was made via histopathology and confirmed with immunohistochem...
Beatriz FR, Marta VG, María MC, Joaquín JF, Esther DF, Luis-Javier EC, Gabriel MD, Manuel IG.An 8-year-old mare mule was presented with a facial mass and history of anorexia, unilateral epistaxis and purulent nasal discharge. The facial mass was encountered from the ventral to the lateral right canthus of the eye up to the facial crest. Thoracic ultrasonography showed five rounded masses. A standing CT under sedation was performed revealing a huge extension and infiltration on surrounding tissues. Due to the extension, type of lesions, outcome and suspicion of metastasis, the owner chose to euthanize the patient. Necropsy confirmed the presence of tumoral lesions spread into the lungs...
Asin J, Nyaoke AC, Samol MA, Arthur RM, Uzal FA.Epiploic foramen entrapment (EFE) is a common cause of small intestinal colic in horses and may lead to intestinal strangulation. Strangulating intestinal obstruction impairs the gastrointestinal outflow and can lead to secondary gastric rupture and endotoxemia. Clostridioides difficile can cause enterotyphlocolitis with colic in horses of all ages, and the process is commonly referred to as C. difficile-associated disease (CDAD). Here we report the results of the postmortem examination of a 7-y-old Thoroughbred racehorse with concurrent CDAD, EFE, and gastric rupture that was euthanized follo...
Macías-Rioseco M, Sheley M, Ochoa J, Carvallo-Chaigneau FR, Uzal FA.Coccidioidomycosis is a fungal disease caused by or . We searched the records of the California Animal Health and Food Safety Laboratory from 1990 through 2020 for cases of coccidioidomycosis in horses. The selection criteria for these cases were: 1) live-born horses submitted for autopsy, and 2) a diagnosis of coccidioidomycosis was established, regardless of cause of death. During that time, 19,054 horses were received, and 26 cases (0.14%) of coccidioidomycosis were diagnosed in horses, of which 19 (73%) cases had pneumonia and/or pleuritis with or without lesions in other organs, and 7 (2...
Sykes CA, Uzal FA, Mete A, Ochoa J, Filigenzi M, Poppenga RH, Asin J.A presumptive postmortem diagnosis of oleander () poisoning is made based on the histological observation of cardiomyocyte degeneration and necrosis, which is considered to be a reliable diagnostic marker, and can be confirmed via the detection of oleandrin in tissues or fluids. However, cardiac lesions may not be present in every case, and autolysis can often preclude the identification of subtle changes in the cardiomyocytes. Several studies of experimental oleander poisoning have noted the presence of renal lesions in multiple mammalian species, and case studies of accidental exposure have ...
Rahman A, Uzal FA, Hassebroek AM, Carvallo FR.Pneumonia is a significant disease of horses. Although pneumonia has traditionally been studied in racehorses, little information is available for non-racing horses. Non-racing horses that died with pulmonary lesions ( = 156) were available from cases submitted for autopsy from January 2015 to June 2020. Bronchopneumonia (35%), interstitial pneumonia (29%), embolic pneumonia (21%), granulomatous pneumonia (13%), and pleuritis (2%) were observed in the examined horses. Seventy-four horses died or were euthanized because of pulmonary diseases, and 82 horses died or were euthanized because of...
Hellings IR, Skjerve E, Karlstam E, Valheim M, Ihler CF, Fintl C.There are no reports on the number of fatalities or causes of death in the Norwegian and Swedish harness racehorses. Objective: The incidence rates (IRs), risk factors, and postmortem findings in horses that died or were euthanized associated with racing between 2014 and 2019 were investigated. Methods: Thirty-eight Standardbreds and 10 Norwegian-Swedish Coldblooded Trotters died or were euthanized associated with racing. A total of 816 085 race-starts were recorded. Methods: Incidence rates were calculated for both countries and horse breeds. Risk factors for sudden death were identified us...
Engiles JB, Uzal FA, Navarro MA, Reef VB, Bender SJ.Phlegmonous gastritis was diagnosed in 2 yearling fillies that were presented with a 1-wk history of fever, lethargy, and hypoproteinemia, associated with a previous diagnosis of equine proliferative enteropathy based on clinical signs and PCR assay detection of Lawsonia intracellularis in fecal samples. Abdominal ultrasound revealed enlargement of the stomach and expansion of its submucosal layer with hypoechoic fluid, as well as thickened hypomotile small intestinal segments. Given the poor prognosis and poor response to treatment, both horses were euthanized, one on the day of presentation ...
Loynachan AT.Pulmonary malformations are rare equine congenital anomalies. Over a 3-year timeframe, three cases of left sided pulmonary agenesis were diagnosed in perinatal foals. All three cases were associated with concurrent ipsilateral diaphragmatic herniation and hypoplasia of the right lung lobe. All three foals died immediately following parturition due to perinatal asphyxia associated with the congenital malformations. To the author's knowledge, this is the first report of pulmonary agenesis in the horse.
Sakurai M, Isshiki S, Sasaki N, Sakai Y, Yamada Y, Morimoto M.A 7-year-old male Thoroughbred horse exhibited recurrent falls followed by convulsive seizures. The horse was clinically diagnosed with epilepsy and phenobarbital treatment was initiated. However, as seizure control was unsuccessful, the animal was euthanized. At necropsy, yellow-brown linear lesions were found extensively at the U-fibres and cingulate gyrus within the cerebral white matter. Histopathologically, linear demyelination and occasional cavitation were observed. Glial cells with yellow-brown pigment granules, which were autofluorescent, positive to the periodic acid-Schiff reaction ...
Leventhal HR, Hassebroek AM, Carvallo F, McKenzie HC.A 14-y-old pony mare was referred after 30-d duration of intermittent pyrexia, anorexia, weight loss, and change in manure consistency. Physical examination revealed a palpable but reducible ventral abdominal mass. Transabdominal ultrasonography revealed multiple distended, hypomotile, and thickened small intestinal loops in close approximation with numerous, well-defined, hyperechoic masses. There was a large amount of echogenic peritoneal fluid; abdominocentesis revealed a neutrophilic and macrophagic inflammatory exudate, and a mixed bacterial population was cultured. Given the poor prognos...
Asin J, Murphy BG, Samol MA, Polanco J, Moore JD, Uzal FA.Rickets is a metabolic bone disease associated with failure of endochondral ossification and impaired osteoid mineralization in growing animals. As a consequence, affected individuals can develop gross and microscopic bone malformations. The most common causes of rickets in domestic species include vitamin D and phosphorus deficiency. Rickets has been described in multiple species; however, comprehensive postmortem characterizations with confirmatory histopathology in equids have not been published. A 6-mo-old, Thoroughbred-cross foal was diagnosed with rickets based on gross autopsy findings ...
Samol MA, Uzal FA, Blanchard PC, Arthur RM, Stover SM.The most prevalent causes of death in racehorses are musculoskeletal injuries, causing ~83% of deaths within the racing industry in California and elsewhere. The vast majority of these injuries have preexisting lesions that predispose to fatal injury. A 4-y-old Thoroughbred colt suffered an acute suspensory apparatus failure, including biaxial proximal sesamoid bone fractures of the right front fetlock, causing loss of support of the fetlock joint and consequent fall with fractures of the cervical and sacral spine. Cervical fracture caused spinal cord damage that resulted in sudden death. A pr...
Abu-Seida AM, Wafy MN, Hassan EA, Ahmed KA.Ocular neoplasms represent 10% of all equine neoplasms and ocular squamous cell carcinoma (OSCC) is the most common one. This report describes the clinical presentation, laboratory, ultrasonography, postmortem, histopathology and immunohistochemistry findings of a mixed ocular neoplasm in a 10-year-old draft mare. The mare had a one-year history of left ocular mass. Complete destruction of the left eye with loss of vision was observed. A large ulcerated mass oozing blood replaced the left eye. Left parotid lymph node was swollen and had a sinus tract discharging pus. Ultrasonography revealed a...
Carrade DD, Owens SD, Galuppo LD, Vidal MA, Ferraro GL, Librach F, Buerchler S, Friedman MS, Walker NJ, Borjesson DL.The development of an allogeneic mesenchymal stem cell (MSC) product to treat equine disorders would be useful; however, there are limited in vivo safety data for horses. We hypothesized that the injection of self (autologous) and non-self (related allogeneic or allogeneic) MSC would not elicit significant alterations in physical examination, gait or synovial fluid parameters when injected into the joints of healthy horses. Methods: Sixteen healthy horses were used in this study. Group 1 consisted of foals (n = 6), group 2 consisted of their dams (n = 5) and group 3 consisted of half-siblings ...
Guest DJ, Smith MR, Allen WR.Autologous mesenchymal progenitor cells (MPCs) purified from bone marrow aspirates are being used in the treatment of superficial digital flexor tendon (SDFT) injuries in the horse with promising results. In this study the fate of autologous and allogeneic MPCs following injection into the SDFT was monitored by stable transfection of MPCs with green fluorescent protein (GFP). Small lesions were created manually in one forelimb SDFT of 2 horses and injected with autologous MPCs, allogeneic MPCs or bone marrow supernatant alone. Post mortem examinations performed after 10 or 34 days revealed GFP...
Science (New York, N.Y.)February 1, 1985
Volume 227, Issue 4686 522-524 doi: 10.1126/science.3880925
Holland CJ, Ristic M, Cole AI, Johnson P, Baker G, Goetz T.Potomac horse fever, a disease characterized by fever, anorexia, leukopenia, and occasional diarrhea, is fatal in approximately 30 percent of affected animals. The seasonal occurrence of the disease (June to October) and evidence of antibodies to the rickettsia Ehrlichia sennetsu in the serum of convalescing horses suggested that a related rickettsia might be the causative agent. Such an agent was isolated in cultured blood monocytes from an experimentally infected pony. This intracytoplasmic organism was adapted to growth in primary cultures of canine blood monocytes. A healthy pony inoculate...
Boyde A.This review presents findings made in studies of large mammalian bones, especially from racehorse training experiments (2-8 years old, third metacarpal, tarsal) and human autopsy orthopaedic femoral implant retrievals and other human biopsy and autopsy cases. Samples were cleaned to analyse mineralized matrix in three dimensions, or poly methyl-methacrylate embedded and micromilled to delete topography and study the superficial c. 0.5-microm two-dimensional section using quantitative backscattered electron imaging. With experimental implant studies in rabbits, observations were also made in vi...
Marasas WF, Kellerman TS, Pienaar JG, Naudé TW.When 2 horses were dosed with cultures of a Fusarium moniliforme isolate that had previously caused only hepatosis, 1 developed brain oedema and hepatosis, and the other only leukoencephalomalacia. A 3rd horse developed both leukoencephalomalacia and hepatosis after being dosed with another isolate obtained from maize which was associated with a natural outbreak of the nervous form of the disease. Since leukoencephalomalacia and hepatosis could be induced by the same culture material, it was concluded that both syndromes were manifestations of the same toxicosis. There was also some evidence t...
Snyder SP, England JJ, McChesney AE.Five of six immunodeficient Arabian foals that died of adenoviral infection were found to be infected with an intestinal coccidian of the genus Cryptosporidium. Various developmental stages of the organism were found in the microvillous border of the intestinal mucosa. The foals had diarrhea but it was not possible to separate the effects of the cryptosporidial infection from those of the concomitant adenoviral enteritis.
Miller MA, Moore GE, Bertin FR, Kritchevsky JE.Postmortem findings in 241 equids admitted to a teaching hospital that were at least 15 years old at autopsy were reviewed (1) to determine disease prevalence, (2) to compare the cause of death (or euthanasia) in equids 15 to 19 years of age (n = 116) with that in equids ≥20 years of age (n = 125), and (3) to catalog coexisting lesions in equids with pituitary pars intermedia dysfunction (PPID). Breed and sex were evenly distributed between the age groups. Death or euthanasia was attributed to disease of the digestive system (41.5%), pituitary gland (12.9%), locomotor system (10.0%), nervous...
Traversa D, Giangaspero A, Iorio R, Otranto D, Paoletti B, Gasser RB.Habronema microstoma and Habronema muscae (Spirurida: Habronematidae) are parasitic nematodes which infect the stomach and/or skin of equids. The accurate diagnosis of gastric habronemosis is central to studying its epidemiology, but data on its distribution and prevalence are lacking, mainly due to the limitations of clinical and coprological diagnosis in live horses. To overcome this constraint, a two-step, semi-nested PCR-based assay was validated (utilizing genetic markers in the nuclear ribosomal DNA) for the specific amplification of H. microstoma or H. muscae DNA from the faeces from ho...
Kiryu K, Machida N, Kashida Y, Yoshihara T, Amada A, Yamamoto T.Five racehorses in apparently normal condition succumbed to sudden cardiac death (SCD) during or shortly after intensive training exercise. Cardiopathologic examination was performed. In 1 of the 5 horses, the use of an electrocardiogram (ECG) recording taken continuously for 440 sec enabled us to analyze some of the arrhythmias in the terminal event of SCD. The ECG tracing exhibited the R-on-T phenomenon following a pair of ventricular premature contractions (VPCs). The phenomenon rapidly degenerated into ventricular fibrillation, which led to cardiac arrest. In all 5 horses cardiopathologic ...
Drobnic M, Radosavljevic D, Cör A, Brittberg M, Strazar K.We compared the quality of debridement of chondral lesions performed by four arthroscopic (SH, shaver; CU, curette; SHCU, shaver and curette; BP, bipolar electrodes) and one open technique (OPEN, scalpel and curette) which are used prior to autologous chondrocyte implantation (ACI). The ex vivo simulation of all five techniques was carried out on six juvenile equine stifle joints. The OPEN, SH and SHCU techniques were tested on knees harvested from six adult human cadavers. The most vertical walls with the least adjacent damage to cartilage were obtained with the OPEN technique. The CU and SHC...
Wright JD, Kelly WR, Waddell AH, Hamilton J.Verminous encephalomyelitis due to Angiostrongylus cantonensis larvae was diagnosed in 2 foals at necropsy. The principal clinical feature was tetraparesis, although history and neurological examination revealed progressive and multifocal neurological disease. At presentation, a tentative diagnosis of parasitic larval migration involving the central nervous system (CNS), presumably due to Strongylus vulgaris, was proposed. Dissection of the spinal cord in one case resulted in recovery of intact larvae of both sexes of A. cantonensis. In both foals, histopathology of the brain and spinal cord r...
Webbon PM.The results of a survey are presented in which 589 limbs from 206 horses were dissected. In174 of the limbs lesions were found in either the superficial (131) or deep (43) digital flexor tendons. Changes occurring with age were also recorded. The sites of the abnormalities and their macroscopical appearance are described and the value of the results is considered in relation to the diagnosis and the treatment of clinical lesions.
Yoshikawa H, Yasu T, Ueki H, Oyamada T, Oishi H, Anzai T, Oikawa M, Yoshikawa T.To evaluate the possibility that Streptococcus equi subsp. zooepidemicus (S.z) the causative bacterial agent of equine shipping fever pneumonia (ESFP), as well as to investigate its pathogenesis, 10 horses (seven Thoroughbreds and three Anglo-Arab species, ranging from 2-4 years in age) were experimentally inoculated, via an endoscope, into bronchus of the lung lobe with a dose of 30 ml of 1-7 x 10(8) CFU/ml of S.z. After inoculation, autopsy and pathological examinations were sequentially conducted 30 min, 1, 2, 3, 4, 17, 20 hr and 2 weeks later. Pneumonia induced by the intrapulmonary inocul...
Molesan A, Wang M, Sun Q, Pierce V, Desideri R, Palmer S, Todhunter R, Kelly K.Postmortem evaluation of racehorses has focused primarily on musculoskeletal injuries; however, horses also die suddenly on the track (sudden death [SD]). Although cardiac conditions are frequently suspected as a cause of death, SD racehorses are often autopsy negative; however, previous studies have been limited due to inconsistent or insufficient cardiac sampling and lack of controls. SD in New York (NY) and Maryland (MD) racehorses was evaluated in an observational case vs control study comparing clinical information, postmortem evaluation including cardiac dissection, and cardiac conductio...
Webb AI, Weaver BM.Seventeen horses were dissected and their organs and tissues weighed. The results of these dissections are presented together with comparisons of the data with that already available in the literature. Predictive equations for organs and tissue weights are also given which were derived by comparison of linear and allometric regression models using 4 different body weight indices.
Fogarty U, del Piero F, Purnell RE, Mosurski KR.The intestinal tracts of 363 horses were examined after slaughter at a horse abattoir. The presence or absence of Anoplocephala perfoliata and the sites of attachment were recorded. A total of 51 per cent of the horses had A perfoliata attached to the mucosa of the ileocaecal junction and/or to the caecal mucosa; 5 per cent of the horses had A perfoliata attached only to the mucosa of the ileocaecal junction, 24 per cent had A perfoliata attached only to the caecal mucosa and 22 per cent of the horses had A perfoliata attached at both sites. The degree of infestation did not appear to be influ...
Getachew AM, Innocent GT, Trawford AF, Feseha G, Reid SJ, Love S.A cross-sectional coprological survey in the regions of Ada, Akaki, Bereh and Boset, and a retrospective postmortem investigation were conducted to study the epidemiology of Parascaris equorum in donkeys and horses in Ethiopia. Faecal samples from 803 working donkeys and 402 horses were collected, and the numbers of worms recovered from 112 donkeys examined postmortem between 1995 and 2004 were analysed. There was a high prevalence of infection and faecal egg output of P equorum in both donkeys and horses, and the severity of the infection in donkeys was increased irrespective of their age. Th...
Brown CM, Kaneene JB, Taylor RF.An analysis was made of the causes of death in horses and ponies over one year of age which died suddenly (Group 1) or were found dead but were considered normal when last seen (Group 2). There were 49 animals in Group 1. Thoroughbreds were overrepresented, but there were no ponies in this group. No cause of death was found in 30.6 per cent of cases and 16.3 per cent died from each of the following causes: haemorrhage in the respiratory system, central nervous system, and adverse drug reactions. Cardiovascular lesions were the cause of death in 14.4 per cent and the remaining 3.1 per cent had ...
Doige CE, McLaughlin BG.Hyperplastic goitre was observed in seven newborn foals. Several were weak at birth and died in the first 48 hours of life. Only one foal had myxedema and only three of the seven had obvious enlargement of the thyroid at necropsy. It is suggested that the goitre observed was caused by a dietary deficiency of iodine.
Martineau H, Thompson H, Taylor D.Gastric ulceration is now widely recognised as an important disease in high performance horses. Little is known about gastric histopathology in healthy or diseased animals; a comprehensive assessment would enhance interpretation of gross findings through assessment of their accuracy and allow for identification of lesion variety and pathogenesis in different anatomical regions of the stomach. Objective: To investigate the true extent and variety of gastric lesions in a mixed population of mature horses at post mortem. Methods: Stomachs were removed from a mixed population of 21 horses at post ...
Taouji S, Collobert C, Gicquel B, Sailleau C, Brisseau N, Moussu C, Breuil MF, Pronost S, Borchers K, Zientara S.Equine herpesviruses type 1 and 4 (EHV-1 and EHV-4) are ubiquitous in the equine population. One of their main properties is their ability to establish life-long latent infections in their hosts even in those with natural or vaccine-induced immunity. However, effect of vaccination status on prevalence and tissue tropism was not established. In this study, EHV-1 and EHV-4 were detected by polymerase chain reaction and by classical virus isolation from neural, epithelial and lymphoid tissues collected from unvaccinated (33) or vaccinated (23) horses. The percentage of EHV-1- and EHV-4-positive h...
Carvallo FR, Uzal FA, Diab SS, Hill AE, Arthur RM.Respiratory diseases have a major impact on racehorses in training and are often cited as the second most common reason of horses failing to perform. Cases were submitted by the California Horse Racing Board to the California Animal Health and Food Safety laboratory for postmortem examination between January 1, 2005 and December 31, 2014. We determined the demographics of racehorses with fatal pneumonia, characterized the pathologic findings in animals with a postmortem diagnosis of respiratory infection, and determined the most significant pathogens associated with lower respiratory tract dis...
Bucknell D, Hoste H, Gasser RB, Beveridge I.The community structure exhibited by strongyloid nematodes from the large intestines of horses was examined using data from autopsies of 150 horses. Thirty-one species of nematodes were encountered, but they were not clearly divisible into core and satellite species. Multiple congeneric, consubfamilial and confamilial species were a prominent feature of the community and were more common than singleton infections. Multivariate analyses provided evidence of a stable community of helminths dominated by positive interactions but with few negative interactions, suggesting the absence of competitio...
Gunson DE, Sweeney CR, Soma LR.Pathologic changes are described in 11 horses that died during racing or training; 9 died of acute pulmonary hemorrhage (exercise-induced pulmonary hemorrhage), 1 died of exsanguination, and 1 died of CNS trauma. Cardiac lesions were not found in any horse. Severe engorgement of pulmonary vessels, with hemorrhage into alveoli, airways, interstitium, and subpleural tissues, was observed in all 9 horses that died of exercise-induced pulmonary hemorrhage. Infiltration of eosinophils and/or lymphocytes around vessels and airways was seen in 6 horses. Focally extensive fibrosis was observed in the ...
Southwood LL, Schott HC, Henry CJ, Kennedy FA, Hines MT, Geor RJ, Hassel DM.Thirty-five cases of disseminated hemangiosarcoma (21 clinical cases and 14 previously reported cases) were reviewed to describe the disease in horses. Hemangiosarcoma occurred in mature, particularly middle-aged horses, with no apparent sex predilection. Thoroughbreds seemed to be overrepresented (13 cases) but a true breed predilection could not be established. The respiratory and musculoskeletal systems were most commonly affected and presenting complaints included dyspnea (26%), subcutaneous or muscular swelling (24%), epistaxis (17%), and lameness (12%). Heart and respiratory rates were u...
Ricketts SW, Greet TR, Glyn PJ, Ginnett CD, McAllister EP, McCaig J, Skinner PH, Webbon PM, Frape DL, Smith GR.An outbreak of pharyngeal and limb paresis involving four horses and nine ponies in the south east of England is described. Nine of the animals died or were destroyed on humane grounds. The clinical features suggested a diagnosis of botulism and mouse innoculation tests confirmed the presence of type B toxin in the serum of one case. All animals were fed big bale silage. It is describe how, in plastic wrapped silage manufacture, conditions of fermentation may be inadequate to prevent the growth of Clostridium botulism. Examination of a sample of silage fed to the affected horses suggested that...
Roby KA, Beech J, Bloom JC, Black M.A yearling Arabian-type filly with a history of poor growth, erythrocytosis, hypoglycemia, and high liver enzyme activities was admitted to the hospital for evaluation. Three days after admission, the filly collapsed, deteriorated rapidly despite treatment, and was euthanatized. A metastatic hepatocellular carcinoma with capsular rupture and hemoperitoneum were found at necropsy. Primary liver tumors are rare in horses, and hepatocellular carcinoma has been reported in only 1 other horse. The systemic manifestations of the tumor in this filly included weakness, weight loss, inappetence, erythr...
