Pyrexia, commonly referred to as fever, is an elevation in body temperature that occurs as a physiological response to various stimuli, including infection, inflammation, or other underlying medical conditions in horses. It is a common clinical sign observed in equine practice and can indicate the presence of an underlying health issue. The regulation of body temperature is controlled by the hypothalamus, and pyrexia results when this regulatory center adjusts the set point to a higher temperature in response to pyrogens, which can be endogenous or exogenous. Monitoring and assessing pyrexia in horses are important for diagnosing and managing potential health problems. This page compiles peer-reviewed research studies and scholarly articles that explore the causes, mechanisms, and implications of pyrexia in equine health, as well as its role in disease processes and treatment considerations.
MacMillan AP, Baskerville A, Hambleton P, Corbel MJ.Five mares, one stallion and a colt foal were inoculated intraconjunctivally with Brucella abortus strain 544. No clinical signs of disease developed except mild pyrexia. Intermittent bacteraemia was detected in the mares but not in the stallion or foal. Antibodies to B abortus became detectable from the second week after inoculation. Titres in the serum agglutination and complement fixation tests declined substantially after six to eight weeks but reactions to the Coombs antiglobulin, 2-mercaptoethanol and immunodiffusion tests were maintained. No consistent changes in biochemical or haematol...
Orrego A, Issel CJ, Montelaro RC, Adams WV.Five serial passages of a cell-adapted strain of equine infectious anemia (EIA) virus were conducted in Shetland ponies. The 13 recipient ponies became agar-gel immunodiffusion test-positive by 25 days after they were inoculated. The virulence of the cell-adapted strain of EIA virus markedly increased through 3 serial passages, although individual variation within passages was high. The 1st serial-passage recipient remained afebrile through 200 days, whereas a febrile episode occurred about every 185, 44, 35, and 33 days in the 2nd, 3rd, 4th, and 5th serial-passage recipients, respectively. Se...
Tennant B, Keirn DR, White KK, Bentinck-Smith J, King JM.Six cases of squamous cell carcinoma of the stomach in horses seen at the New York State College of Veterinary Medicine are compared with 15 similar cases reported previously. Clinical signs included anorexia in all cases, emaciation, fever, anaemia and/or palpable abdominal masses in 3, colic in 2 and dysphagia in one case. Haematological studies revealed normochromic, normocytic anaemia in 3 and absolute neutrophilia in 5 cases. Peritoneal fluid analysis was performed in 4 cases and revealed slightly to moderately elevated total protein concentrations in 3 and a markedly elevated number of w...
Roberts MC, O'Boyle DA.Salmonella anatum was given orally to 8 horses on 11 occasions in doses ranging from 9.5 X 10(6) to 8.8 X 10(11) organisms. Four distinct syndromes were induced based upon clinical, laboratory and pathological findings: (1) asymptomatic; (2) moderate clinical signs with or without changes in faecal consistency; (3) fever, depression, anorexia with unstructured or diarrhoeic faeces; and (4) septicaemia with or without diarrhoea, and peripheral circulatory failure. All animals excreted the organism. The peak temperature preceded the onset of diarrhoea by 1 or 2 days. Changes in faecal consistenc...
Prescott JF, Srivastava SK, deGannes R, Barnum DA.A mild form of strangles caused by an atypical Streptococcus equi was recognized on a large horse breeding farm. The organism differed from most S equi isolates by disappearance of the mucoid capsule by 24 hours of culture, leaving a matt-type colony. Typically, the clinical signs were a transient (24-48 hour) fever, profuse nasal discharge, and anorexia. In about half the affected animals, there was moderate mandibular lymph node enlargement, and these glands usually ruptured or were drained. The use of a passive hemagglutination antibody test showed that subclinical infection was widespread ...
McClure JJ, Lindsay WA, Taylor W, Ochoa R, Issel CJ, Coulter SJ.In 4 horses with equine infectious anemia (EIA), the predominant clinical sign was ataxia. Other clinical and laboratory findings often associated with EIA included weight loss, anemia, pyrexia, thrombocytopenia, hemorrhages, hypergammaglobulinemia, and high activity of biliary epithelial enzymes. Neuropathologic findings were nonsuppurative granulomatous ependymitis, meningitis, and encephalomyelitis and plasmacytic-lymphocytic infiltration of the brain and spinal cord. The onset of neurologic signs corresponded to the acute stage of infection in at least 2 horses, and the signs developed at ...
Burrows GE.The response of the pony to increasing doses of Escherichia coli endotoxin was evaluated using intravenous and intraperitoneal administration models. Marked changes were seen in all parameters measured following endotoxin administration. Leukopenia (neutropenia, lymphopenia) and thrombocytopenia were not dose-dependent. Similarly, elevated plasma fibrinogen and altered glucose concentrations (hyperglycemia and hypoglycemia), pyrexia and increased lactate/pyruvate ratios were apparent at all endotoxin doses but were not dose related. The widely used packed cell volume and capillary refill time,...
Justines G, Oro G, Alvarez O.The P-676 and MF-8 epizootic strains of Venezuelan equine encephalitis (VEE) virus were found to contain a minute plaque (MP), different from the predominant small plaque (SP) present in these virus strains. The MP and SP were stable after passages in Vero cells, mice, or horses. Equines were inoculated with the SP or MP of the P-676 and MF-8 strains. Inoculation of either P-676 SP or MP into horses induced high fever and viremia but no signs of encephalitis or death. Four horses infected with MF-8 SP became very ill, with high fever and viremia; three of the inoculated animals died. Four hors...
Burrows GE.Phenylbutazone (PBZ), a classic anti-inflammatory and prostaglandin-synthesis inhibitor drug, was used to determine the role of prostaglandins and other mediators on the development and perpetuation of the response to intraperitoneal Escherichia coli endotoxin administration. The PBZ (15 mg/kg of body weight) was administered IV 30 minutes after endotoxin administration and was repeated later at 6 and 12 hours at a dose of 10 mg/kg. A variety of evaluation measurements (hematologic, blood glucose, pyruvate, lactate and fibrinogen, serum beta-glucuronidase, prothrombin time, blood gases, hepati...
Stowe HD.Thirty-four adult ponies were used to determine the effects of single oral doses of copper (Cu) supplements (0, 20, and 40 mg of Cu/kg of body weight) on the toxicity of oral doses of selenium (Se) supplements (0, 2, 4, 6, and 8 mg of Se/kg of body weight) administered 24 hours after the copper was given. Signs of Se toxicosis-sweating, diarrhea, tachycardia, tachypnea, mild pyrexia, lethargy, and colic-developed in ponies given 6 and 8 mg of Se/kg of body weight without Cu pretreatment. Two of 4 ponies given 6 mg of Se/kg and both ponies given 8 mg of Se/kg without Cu pretreatment died within...
Mason TA.A case of bicipital bursitis in a six-year-old mare is described. The horse was presented with acute lameness, pyrexia and hot swelling over the right shoulder region. Although antibiotic treatment relieved these signs, a firm cold swelling remained which had to be removed by surgical resection and drainage.
Smith BP.Salmonellosis in horses may result in fever, anorexia, and depression without concurrent diarrhea or other obvious gastrointestinal abnormalities and should be considered in cases of fever of unknown origin. The syndrome also is characterized by neutropenia, usually with a left shift, and growth of small numbers of salmonella from feces cultured in selenite enrichment broth. Repeated culturing may be necessary to isolate the organism. All six affected horses of this report recovered in 3 to 7 days without specific therapy.
Owen R, Fullerton JN, Tizard IR, Lumsden JH, Barnum DA.Clinical, bacteriological, serological and haematological observations were made on 13 adult ponies orally inoculated with Salmonella typhimurium. The results were compared to two control ponies and four others infected by accidental transmission. The clinical responses in inoculated ponies included pyrexia lasting four days and neutropaenia during the first five days after inoculation followed by a neutrophilia. Pyrexia and neutropaenia was associated with maximal shedding of organisms in the rectal faeces. Changes in the character of the faeces occurred between one and two days after inocula...
Burrows GE.Repeated exposure of ponies in Escherichia coli endotoxin resulted in attenuation of the packed cell volume, beta-glucuronidase, capillary refill time and neutrophil responses usually accompanying endotoxin administration. An overall decrease in severity of clinical response including reduced mortality was also apparent in ponies with repeated endotoxin exposure. Modification of the febrile response was not observed in any of the experimental groups.
Crandell RA, Drysdale S, Stein TL.The clinical and immunological response of ponies exposed to a bovine herpesvirus isolate and equine herpesvirus 1 were compared. Each virus was inoculated into two ponies by the intranasal route. One uninoculated pony was used with each group as a contact control. The four inoculated ponies developed a mild rhinitis with an increase in rectal temperature. Virus was recovered from nasal secretions collected from the four inoculated and one contact pony. All ponies developed a serum neutralizing antibody to each virus. The data show that the two viruses are similar.
Reynolds DJ, Nicholl TK.A 5 month old colt foal with recurrent pyrexia and a loud pansystolic murmur later developed signs of cardiac failure. Peritoneal fluid and blood samples both demonstrated an extreme leucocytosis and neutrophilia. At post-mortem both a cranial mesenteric arteritis and the congenital cardiac anomaly, Tetralogy of Fallot were found. The detailed clinical and post-mortem findings contributing to the case are described.
Duncan JL, Pirie HM.The clinical signs, pathology and clinical pathology associated with single experimental infections of Strongylus vulgaris in worm-free pony foals are described. The major clinical signs which became apparent in the infected foals during the first three weeks were pyrexia, anorexia, dullness and abdominal pain. Within the first two weeks of infection lesions were confined to the intestine and terminal branches of the intestinal arteries and consisted of mucosal, submucosal and serosal haemorrhage together with arteritis of submucosal and serosal arteries and also a marked inflammatory reaction...
Dorn CR, Coffman JR, Schmidt DA, Garner HE, Addison JB, McCune EL.Colitis due to salmonellae was diagnosed in 9 horses following hospitalization for various reasons at the University of Missouri Veterinary Teaching Hospital, from May, 1971, to April, 1972. Diarrhea, fever, and either a neutrophil count of less than or equal to 3,600/cmm or a rapid decline in neutrophil numbers were specific for salmonellosis. The value of hematologic survelillance in hospitalized Equidae was demonstrated in another group of 9 horses with neutropenia, each of which was promptly treated and did not develop colitis. Bacteriologic culturing of fecal samples from 28 clinically no...
Walton TE, Alvarez O, Buckwalter RM, Johnson KM.Ten horses (Equus caballus) were vaccinated with strain TC-83 Venezuelan equine encephalomyelitis (VEE) virus vaccine. Febrile responses and leukopenia due to a reduction of lymphocytes and neutrophils were observed in all animals. Viremias were demonstrable in eight horses, with a maximum of 10(3.5) median tissue culture infectious dose units per ml of serum in two horses. Clinical illness with depression and anorexia were observed in five horses. Neutralizing (N), hemagglutination-inhibiting, and complement-fixing antibodies to the vaccine virus were demonstrable by 5, 6.5, and 7 days, respe...
MacKay RJ, Merritt AM, Zertuche JM, Whittington M, Skelley LA.Serum and plasma from horses injected with endotoxin was examined for cytotoxic activity. Each of the cell lines, L929 and WEHI 164 clone 13, was sensitive to the cytotoxic effects of equine serum; however, a precipitation artifact caused by the use of isopropanol in the WEHI assay limited the use of this assay to samples containing less than 2 mg of protein/ml. In foals treated with a sublethal IV bolus of 5 micrograms of lipopolysaccharide (LPS)/kg and in adult horses given a low-dose continuous infusion of LPS (30 ng/kg/h for 4 hours), cytotoxic activity was detected in all serum or plasma ...
Avila VA, López-GarcÃa Y, Hernández-Castro R, Salas-Garrido CG, RamÃrez-Lezama J, Calderón-Villa R, MartÃnez-ChavarrÃa LC.Aberrant nematode larval migration in the CNS of horses is rare but frequently fatal; one of the main etiological agents involved in this illness is Halicephalobus gingivalis. This soil nematode has been associated with several fatal equine meningoencephalitis reports worldwide; however, it had never been diagnosed in horses of Mexico. A 10 year-old Andalusian horse presented dysphagia, fever, weakness, prostration and ataxia; the patient expired during the medical attention. Post mortem examination was performed and no gross alterations were found. Histopathology revealed meningoencephalitis...
Grewar JD, Thompson PN, Lourens CW, Guthrie AJ.Thoroughbred foal body temperature data were collected from shortly after birth until shortly after weaning during the 2007/2008 season on a stud farm in the Western Cape Province of South Africa. Equine encephalosis (EE) caused by EE virus (EEV) serotype 4 (EEV-4) occurred in the foal group during the first autumn after their birth (March and April 2008). A descriptive study was undertaken to provide data on the EEV maternal antibody status, the association between pyrexia and EEV infection, and the incidence of infection amongst the foals prior to and during the episode. This included the fr...
Saville WJ, Hinchcliff KW, Moore BR, Kohn CW, Reed SM, Mitten LA, Rivas LJ.The clinical and clinicopathologic characteristics of fatal necrotizing enterocolitis were examined in 16 horses (age 4 months to 12 years). At initial presentation, 8 of 16 horses were pyrexic (median temperature, 38.4 degrees C; range, 33.8 to 40.6 degrees C); all 16 were tachycardic (median heart rate, 93 bpm, range, 66 to 138 bpm); 13 of 16 were tachypneic (median heart rate, 36 bpm, range, 16 to 80 bpm), dehydrated, and had discolored mucous membranes. All horses that were pyrexic were also tachycardic and tachypneic. PCV was high (> 45%) in 14 horses. Six horses were leukopenic (< 5,000 ...
Sim RR, Joyner PH, Padilla LR, Anikis P, Aitken-Palmer C.Anaplasma phagocytophilum is a tick-borne pathogen of domestic horses and the causative agent of equine granulocytic anaplasmosis. This case series describes three confirmed cases of clinical anaplasmosis, and a fourth case of presumptive anaplasmosis in Przewalski's horses ( Equus ferus przewalskii) housed at the Smithsonian Conservation Biology Institute from 2008 to 2014. Clinical signs varied among individuals with affected horses exhibiting lethargy, weakness, pyrexia, hypophagia, reluctance to move, or ataxia. Anaplasmosis cases were confirmed with a combination of identification of neut...
Meichner K, Kraszeski BH, Durrant JR, Grindem CB, Breuhaus BA, Moore PF, Neel JA, Linder KE, Borst LB, Fogle JE, Tarigo JL.An 11-year-old, 443-kg Haflinger mare was presented to the North Carolina State University Veterinary Teaching Hospital with a 2-week history of lethargy and a 3-day duration of anorexia, pyrexia, tachycardia, and ventral edema. Severe pitting edema, peripheral lymphadenopathy, and a caudal abdominal mass were noted on physical examination. An extreme leukocytosis (154.3 × 103 /μL) and microscopic hematologic findings suggestive of myelomonocytic leukemia were observed. Serum protein electrophoresis revealed a monoclonal gammopathy and urine protein electrophoresis revealed a monoclonal ligh...
De Clercq D, van Loon G, Nollet H, Delesalle C, Lefère L, Deprez P.Between 1999 and 2001, seven horses with fever, dysphagia and a history of chronic upper respiratory tract infection lasting between three weeks and three months were examined. They had been treated unsuccessfully with a variety of antibiotics for three to four weeks. A deep abscess in a retropharyngeal lymph node was diagnosed in each case by clinical examination, endoscopy and echographic examination of the retropharyngeal region. The infected retropharyngeal lymph node of each horse was punctured with a spinal needle under ultrasound guidance. Pus was aspirated from four of the horses, and ...
Reef VB, Bain FT, Spencer PA.Forty-three horses with mitral regurgitation (MR) and congestive heart failure were examined, using M-mode, 2-dimensional real-time and Doppler echocardiography. There was no breed or sex predisposition when compared to the general hospital population. The mean +/- s.d. age of affected horses was 7.6 +/- 8.1 years. Horses with MR and congestive heart failure had significant increases in mean values for left ventricular chamber size, left atrial size and heart rate and significant decreases in interventricular septal and left ventricular free wall thickness. Significant increases in pulmonary a...
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...
Jahn P, Zeman P, Bezdekova B, Praskova I.Twelve confirmed cases of equine granulocytic anaplasmosis (EGA) and five additional suspected cases, showing a compatible clinical history and specific IgG titres of 1280 or above, were recorded in the Czech Republic during the period 2002 to 2008. The diagnosis was based on clinical signs, the detection of Anaplasma phagocytophilum morulae in neutrophils in blood smears, serology and molecular methods. Pyrexia (39.8 to 41.3 degrees C), depression, partial or total anorexia, limb oedema and icterus were the most frequently observed clinical abnormalities. Haematological examination revealed t...
Shinwari MW, Annand EJ, Driver L, Warrilow D, Harrower B, Allcock RJ, Pukallus D, Harper J, Bingham J, Kung N, Diallo IS.In May 2013, the first cases of Australian bat lyssavirus infections in domestic animals were identified in Australia. Two horses (filly-H1 and gelding-H2) were infected with the Yellow-bellied sheathtail bat (YBST) variant of Australian bat lyssavirus (ABLV). The horses presented with neurological signs, pyrexia and progressing ataxia. Intra-cytoplasmic inclusion bodies (Negri bodies) were detected in some Purkinje neurons in haematoxylin and eosin (H&E) stained sections from the brain of one of the two infected horses (H2) by histological examination. A morphological diagnosis of sub-acute m...
Nyack B, Padmore CL, Dunn D, Kufuor-Mensan E, Mobini S.A 10-year-old Tennessee Walker gelding, with a history of progressive weight loss, intermittent colic and lethargy, had a slight fever, tachycardia, tachypnea, pallor, ascites and marked ventral edema. Blood analyses revealed anemia, leukocytosis, neutrophilia with a left shift, lymphopenia, monocytosis, hypoproteinemia and a slightly increased SDH level. Abdominocentesis produced red-orange fluid with many RBC and an increased fibrinogen content. Rectal palpation revealed a large mass in the left caudal abdominal quadrant. The animal died shortly after resection of the mass. The histopatholog...
Burrows GE.Phenylbutazone (PBZ), a classic anti-inflammatory and prostaglandin-synthesis inhibitor drug, was used to determine the role of prostaglandins and other mediators on the development and perpetuation of the response to intraperitoneal Escherichia coli endotoxin administration. The PBZ (15 mg/kg of body weight) was administered IV 30 minutes after endotoxin administration and was repeated later at 6 and 12 hours at a dose of 10 mg/kg. A variety of evaluation measurements (hematologic, blood glucose, pyruvate, lactate and fibrinogen, serum beta-glucuronidase, prothrombin time, blood gases, hepati...
Monreal L, Villatoro AJ, Hooghuis H, Ros I, Timoney PJ.During 1992, a widespread outbreak of Equine viral arteritis (EVA) occurred at a riding establishment near Barcelona, Spain. A total of 31 out of 186 horses on the premises displayed clinical signs, most frequently, fever, depression, mild ventral and limb oedema and a vesicular-erosive stomatitis, with hypersalivation, petechiations and small ulcerations. Affected horses developed illness of varying severity with only a few exhibiting a severe form of the disease and no mortality was recorded. Haematological and blood biochemical examination the most severely affected horses revealed a thromb...
Easterwood L, Chaffin MK, Marsh PS, Porter B, Barr C.66 horses were potentially exposed to phosphine (a gas) 14 hours after being fed a pelleted ration treated with aluminum phosphide. Results: 28 horses had clinical signs of profuse sweating, tachycardia, tachypnea, pyrexia, ataxia, seizures, and widespread muscle tremors. Clinically relevant laboratory findings included hypoglycemia and high plasma concentrations of lactate and ammonia and activities of gamma-glutamyl transpeptidase, aspartate aminotransferase, and alkaline phosphatase. At least 4 horses had signs consistent with hepatic encephalopathy. Necropsy findings included petechial and...
Michishita M, Shibata R, Machida Y, Matsumoto M, Ochiai K, Azakami D.A 20-year-old Dutch Warmblood gelding was referred with clinical signs of anorexia, weight loss, intermittent fever, cough, subcutaneous oedema and exercise intolerance. Haematological examination revealed the presence of blast cells, decreased lymphocytes, mild thrombocytopenia and anaemia but no leucocytosis. Serum analyses detected elevated aspartate aminotransferase and gamma-glutamyl transferase activities and triglyceride concentrations. Twenty-two days after the initial visit, the horse died after showing clinical signs of decreased appetite, increased body temperature, tachypnoea and t...
Linn-Peirano SC, Hepworth-Warren K, Kinsella H, Diaz-Campos D, Brenseke BM, Cianciolo RE, Schroeder E, Schreeg ME.Equine ingesta-associated choledocholithiasis is a rare cause of morbidity and mortality. We describe here the clinical, gross, histologic, and microbiologic features of this condition in 2 horses and compare the features to 2 previous cases. Case 1 was a 4-y-old Thoroughbred mare with colic. Case 2 was an 18-y-old American Paint Horse mare with colic, chronic weight loss, and inappropriate mentation. Both had elevated biochemical markers of hepatocellular injury and cholestasis and were euthanized given a poor prognosis. Case 1 had a well-formed 5-cm choledocholith surrounding a piece of hay,...
du Toit N, Genovese LM, Dalziel RG, Smith SH.A 36-year-old donkey developed dyspnoea, pyrexia, hypoalbuminaemia and oedema. Following continued clinical deterioration the donkey was humanely destroyed. Grossly, there were numerous nodules (5-10mm) scattered throughout the lung. Microscopically, the lung was infiltrated by an angiocentric and bronchocentric to diffuse mixed population of small mature and atypical lymphocytes, histiocytes, plasma cells and fewer eosinophils. The infiltrate was composed of numerous small mature and fewer atypical CD3(+) T lymphocytes. Low numbers of CD20(+) and CD79a(+) B cells, some atypical, accompanied t...
Boyle AG, Higgins JC, Durando MM, Galuppo LD, Werner JA, Decock HE.A 22-year-old female Welsh-cross pony was evaluated because of intermittent colic, signs of depression, pyrexia, anorexia, muscle wasting with abdominal distention, and weight gain over the preceding 12 months. A large abdominal mass was detected and surgically removed; the hemodynamic alterations and complications caused by the dramatic fluid losses and shifts that can occur in association with removal of a large abdominal mass required extensive postoperative management. Monitoring of clinical and hematologic variables such as attitude, heart rate, mucous membrane color, mean arterial blood ...
Kimble KM, Gomez G, Szule JA, Dubey JP, Buchanan B, Porter BF.An adult American Quarter Horse gelding with a history of weight loss presented with an acute onset of colic, fever, soft faeces and elevated liver enzymes. At necropsy, there were gastric mucosal masses and evidence of caecal necrosis. Histologically, the masses were lymph nodes with granulomatous inflammation and areas of liquefactive necrosis. Within and surrounding necrotic areas were free and intrahistiocytic clusters of protozoal tachyzoites. Similar but milder inflammation was evident in the spleen, lungs and liver. Necrotizing typhlitis was also evident. Immunolabelling for Toxoplasma ...
Reynolds DJ, Nicholl TK.A 5 month old colt foal with recurrent pyrexia and a loud pansystolic murmur later developed signs of cardiac failure. Peritoneal fluid and blood samples both demonstrated an extreme leucocytosis and neutrophilia. At post-mortem both a cranial mesenteric arteritis and the congenital cardiac anomaly, Tetralogy of Fallot were found. The detailed clinical and post-mortem findings contributing to the case are described.
Osterrieder K, Dorman DC, Burgess BA, Goehring LS, Gross P, Neinast C, Pusterla N, Hussey GS, Lunn DP.Equine herpes virus type 1 (EHV-1) infection in horses is associated with respiratory and neurologic disease, abortion, and neonatal death. Objective: Vaccines decrease the occurrence of clinical disease in EHV-1-infected horses. Methods: A systematic review was performed searching multiple databases to identify relevant studies. Selection criteria were original peer-reviewed research reports that investigated the in vivo use of vaccines for the prevention of disease caused by EHV-1 in domesticated horses. Main outcomes of interest included pyrexia, abortion, neurologic disease, viremia, and n...
Morgan JM, Aceto H, Manzi T, Davidson EJ.Complications are a practical consideration for elective magnetic resonance imaging (MRI) studies performed under general anaesthesia but relatively little is known about their distribution and risk factors. Objective: To describe the incidence of complications associated with MRI performed under general anaesthesia at a large referral facility and evaluate potential risk factors for these complications. Methods: Retrospective case-control study. Methods: Patient information and details of the MRI procedure were collected retrospectively from medical records of all horses that had undergone an...
