Entrapment of the small intestine in the epiploic foramen in horses: a retrospective analysis of 71 cases recorded between 1991 and 2001

The clinical features of 71 cases in 70 horses in which part of the small intestine became entrapped in the epiploic foramen are described. The horses' sex, age and breed, the month during which they were affected, and whether they exhibited stereotypic behaviour were compared with the same variables in 1279 horses which suffered other types of surgical colic during the same period. Thoroughbred and thoroughbred cross horses were over-represented among the 70 affected horses. There was no age or sex predilection. Fifty-five (77.5 per cent) of the cases occurred between October and March and 15 (21.1 per cent) occurred in January. The cases were significantly more likely to have a history of crib-biting/windsucking than the control group (odds ratio 7.9, 95 per cent confidence interval 4.1 to 15.3). The condition had recurred in two of the horses. Fifty-eight (81.7 per cent) recovered from surgery and 49 (69 per cent) survived until they were discharged from hospital. The median survival time of 31 of the affected horses discharged from the hospital was 700 days, whereas 417 horses with other types of surgical colic had a median survival time in excess of 1931 days.     

Sudden and unexpected death in horses and ponies: an analysis of 200 cases

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 lesions of the gastrointestinal system. Racehorses mostly died suddenly from severe haemorrhage in various sites, particularly the thorax. In Group 2 there were 151 animals, and in 33.1 per cent no cause of death was determined. Gastrointestinal lesions were considered the cause of death in 39.2 per cent of cases and respiratory lesions killed 8.6 per cent. Lesions of both the central nervous system and cardiovascular system were considered the cause in 4.6 per cent of cases. The remaining 9.9 per cent of animals had miscellaneous lesions. Toxicological studies were performed in 46 of the total 200 cases, and only two had positive results; lead in one and nicotine in the other.     

Idiopathic focal eosinophilic enteritis associated with small intestinal obstruction in 6 horses

OBJECTIVE: To report the history, clinical findings, and outcome of horses with idiopathic focal eosinophilic enteritis associated with acute small intestinal obstruction. STUDY DESIGN: Retrospective study. ANIMALS: Six horses with idiopathic focal eosinophilic enteritis. METHODS: Retrospective review of medical records of horses with idiopathic focal eosinophilic enteritis, with acute abdominal pain and small intestinal obstruction, associated with a focal region of eosinophilic enteritis of unknown cause. Information retrieved from the medical records included signalment, physical examination, laboratory findings, surgical procedure, histologic diagnosis, and postoperative management. Outcome was determined by telephone communication with owners. RESULTS: Six horses met the selection criteria. Horses had persistent pain, distended small intestine, and nasogastric reflux. Idiopathic focal eosinophilic enteritis lesions associated with a small intestinal obstruction were treated surgically by intestinal resection and anastomosis or wedge resection. There were no observed complications associated with extension of the disease from the lesion site. Five horses were alive at follow-up 5 to 60 months after surgery. CONCLUSIONS: Although the cause of these focal eosinophilic enteritis lesions is unknown, the long-term outcome after lesion resection was favorable. CLINICAL RELEVANCE: Small intestinal obstruction associated with a focal eosinophilic enteritis lesion may be a cause of acute abdominal pain in horses. Horses apparently have a good prognosis after lesion resection.     

Retrospective study of scintigraphic and radiological findings in 21 cases of enostosis-like lesions in horses

Records of horses admitted to a veterinary surgery in the UK for lameness investigation during 2000 to 2008 were reviewed. Twenty-one horses were identified with both scintigraphic and radiological evidence of enostosis-like lesions (ELLs), in which 68 individual foci of increased radiopharmaceutical uptake were confirmed in 57 long bones. The presenting lameness was attributed to ELLs in 15 of 21 (71 per cent) horses; the remainder were thought to be incidental findings. Five horses were subjected to a repeat examination, four of which showed the occurrence of new lesions in the same or different limbs. Hindlimbs had significantly more lesions than forelimbs, but there was no difference between the right and left limbs. All 18 horses for which follow-up information was available were treated conservatively and returned to soundness after a variable period of time. Following ELL resolution, thoroughbred horses performed at a similar level to that before investigation and diagnosis.     

Electrocardiography in the horse. (A report of findings in 138 horses)

Over a period of approx. 3 years, electrocardiograms (ECG) were recorded from 138 horses referred as patients to the Medical Clinic. Of these, 22 horses (approx. 16 per cent) has ECG alterations. The 22 ECG's revealed a total of 29 ECG abnormalities. The most frequent ECG alteration was incomplete AV block, that was seen in 9 horses (31 per cent of the ECG abnormalities). Abnormal (i.e. broad, tent-like and, sometimes, inverted) T waves and deviations of the ST segment were seen each in 5 ECG's from 7 horses, 3 of which had both abnormalities which were associated with severe underlying disease (colic, enteritis, pneumonia, strangles a.o.). Premature ventricular beats were seen in 3 horses, two of which had serious cardiovascular dysfunction whereas the third showed no signs of cardiac disease. Atrial fibrillation was observed in two horses. Both were treated with chinidine sulphate but a conversion to sinus rhythm was not achieved in either case. Other ECG abnormalities observed in the study were, parasystole (1 horse), sinus arrhythmia (2 horses), sinoatrial block (1 horse) and wandering pacemaker (1 horse). Each abnormality is discussed with regard to its clinical significance and diagnosis. Cardiac murmurs were detected on auscultation of 26 horses (approx. 19 per cent). The murmurs in 15 horses were short and faint sounds most of which were diastolic. They were considered of no importance. Eleven horses, on the other hand, had distinct, loud (grade 4 or 5), holosystolic or holodiastolic murmurs that were considered pathological. Eight of these horses had actual signs of cardiac disease. Cardiac vector distribution in patients with ECG abnormalities or murmurs showed no systematic differences from vectors in horses showing no cardiac abnormality.     

The indications for equine laparotomy--an analysis of 140 cases.

The indications for laparotomy in 140 horses are analysed, with particular emphasis on the operative or autopsy findings in 82 cases of colic. In cases of exploratory laparotomy, the overall recovery rate was only 28 per cent but 48 of the 82 animals were considered to have inoperable lesions. The recovery rate and causes of death for each indication are briefly reviewed.     

Bacteria in enteric lesions of horses

Thirty-three species of bacteria were isolated from the gastrointestinal mucosa of 23 adult horses and two foals. The bacteria isolated could be related to gross and microscopical lesions in some cases. Clostridium perfringens type A, Actinobacillus equuli, Salmonella typhimurium and Campylobacter coli biotype 1 could all be associated with gastrointestinal lesions. C jejuni biotype 1 and Aeromonas hydrophila were both recovered in this study and have been identified as causes of enteritis in horses or in other species. The case of C coli enteritis appears to be the first such report. The difficulties in examining adult horses with enteritis and relating the lesions seen to the bacteria isolated are discussed.     

Study of the short- and long-term outcomes of 65 horses with peritonitis

The records of 65 horses with peritonitis examined at two uk referral centres over a period of 12 years were reviewed. Peritonitis was defined in terms of the horse's peritoneal fluid containing more than 5 x 10(9) nucleated cells/l. Horses that had developed peritonitis after abdominal surgery or a rupture of the gastrointestinal tract were excluded. Of the 65 horses, 56 (86 per cent) survived to be discharged. Follow-up information was obtained from practice records and telephone calls to the owners for 38 of the horses. Of these, 32 (84 per cent) had survived for at least 12 months and were considered to be long-term survivors; the others six were euthanased within 12 months. Thirteen (34 per cent) of the horses discharged had experienced complications that could have been sequelae to peritonitis and eight of the 13 were euthanased. The cause of the peritonitis was identified in 15 cases; survival rates were lowest in horses with peritonitis secondary to urinary tract involvement or intra-abdominal masses. Of the other 50 cases, 47 (94 per cent) survived to discharge, but two were euthanased owing to recurrent colic.     

Gastric ulceration in mature thoroughbred horses

Routine post mortem examination of 195 Thoroughbreds in Hong Kong revealed that 66 per cent suffered from gastric ulceration. Racehorses killed straight out of training suffered a significantly greater incidence of ulceration (80 per cent) than those having been retired for a month or more (52 per cent). The macroscopic findings post mortem enabled a classification of equine gastric ulceration to be suggested (Types 1, 2, 3), according to severity. Severe lesions (Types 2 and 3) were present in 45 per cent of horses put down from training and 5 per cent of retired horses. This difference was significant. Lesions appeared to be chronically progressive during training, but to regress during retirement. The observed difference of gastric ulceration between the two groups of horses was similar for different age groups.     

Studies of necrotizing enteritis of suckling piglets (Clostridium perfringens type C enterotoxemia) in industrialized sow breeding units. 4. Epizootiology]

Necrotising enteritis had been the cause of death of 4.9 per cent in 5,177 nursed piglets, which was established by pathological examination. The number of piglets, in that context, which had come from industrialised sow breeding units was equivalent to 92 per cent. The nursed piglet held the third position, next to smaller ruminants (19.4 per cent) and fowl (6.0 per cent), with regard to the occurrence of Clostridium perfringens enterotoxemia or necrotising enteritis in 112,218 animals which were pathologically examined after death. Necrotising enteritis so far has been rare in the GDR. No regional accumulation has been observed. Several outbreaks on industrialised sow breeding units actually remained stationary. The occurrence of the disease may be favoured by a number of factors which are conducive to accumulation of Clostridium perfringens Type C in a given stock. Group keeping of pregnant sows, simultaneous farrowing of larger groups of sows, group treatment of nursed piglets, using neomycin, chloramphenicol, oxytetracycline, and other antibiotics to which Clostridium perfringens is primarily resistant or has acquired resistance in the course of time are some of those contributive factors. Transmission of Clostridium perfringens Type C through feedstuff is possible, though it would lead to a real outbreak only by high intensity of the contamination, and it played a minor role in proliferation of the disease. 3479 Clostridium perfringens strains were isolated from 9,481 animals, both clinically intact and after death, with 30 species being included. Type classification revealed 2454 strains of Type A (70 per cent), 204 of Type D (5.88 per cent), 164 of Type C (four per cent), and 48 of Type B (1.34 per cent). There were 688 atoxic strains (17 per cent). Swine is the major carrier of Clostridium perfringens Type C, with 87 per cent of all Clostridium perfringens Type C strains having been isolated from swine. Swine was followed by fowl (four per cent), sheep (four per cent), cattle, rabbit, and dog (1.27 per cent each). Clostridium perfringens Type C was obtained from the faeces of clinically intact sows in seven instances, including two cases with sows (0.46 per cent) from farms with no previous record of necrotising enteritis.     

Obstruction of equine small intestine associated with focal idiopathic eosinophilic enteritis: An emerging disease?

Idiopathic focal eosinophilic enteritis (IFEE) is a rare disease in the horse and few cases have been reported in the literature. The objective of this paper was to describe the clinical, surgical, histological features and post-operative progress of 12 horses with IFEE, a disease that had not been identified in the authors' hospital population prior to 2000. Diagnosis of IFEE was made at laparotomy and confirmed by histological examination of resected abnormal small intestine. In all 12 horses colic was associated with jejunal obstruction involving visibly striking and palpably thickened serosal plaques or circumferential constrictions. Surgical resection of affected intestine was performed in 10 horses, of which seven completely recovered. In one horse, on which surgical resection was not performed, ingesta re-obstructed post-operatively at one of the lesions. Histological examination of resected intestines revealed, in all cases, severe transmural enteritis in which eosinophilic leucocytes were the predominant inflammatory cells. No helminths were identified and the cause of this lesion is not known. IFEE is an uncommon but significant cause of small intestinal obstruction for which surgical resection can be curative. The gross lesions may be under-recognised and histology is essential for diagnosis.     

Small intestinal malabsorption in the horse: an assessment of the specificity of the oral glucose tolerance test

Specificity of the oral glucose tolerance test (OGTT) for the diagnosis of small intestinal malabsorption in the horse was assessed by comparing the results of OGTT with the results of a histopathological examination of the small intestine in 42 adult horses affected by chronic weight loss. The horses were assigned to three groups on the basis of the results of the test. Five horses were considered to have a normal OGTT absorption result (Group 1); all the horses had a histologically normal small intestine. Twenty-five horses had a partial malabsorption result (Group 2) seven of which had normal small intestinal morphology, whereas the remaining 18 had a variety of pathological lesions including lymphosarcoma, villous atrophy, granulomatous enteritis and eosinophilic gastroenteritis. Twelve of the 42 horses had a total malabsorption result (Group 3), and all had a severe infiltrative lesion in the small intestinal wall (either lymphosarcoma or granulomatous enteritis).     

Incidence of exertional rhabdomyolysis in polo horses in the USA and the United Kingdom in the 1999/2000 season

A questionnaire was used to determine the incidence of exertional rhabdomyolysis and the factors that might have contributed to its occurrence among 423 polo horses in 11 yards. The yards were selected at random, six of them with 111 horses, in north-eastern USA, and five with 312 horses in south-east England. During the 1999/2000 season the incidence of the condition was 7.3 per cent (9 per cent in the USA and 6.7 per cent in England). The incidence in mares was similar in the two countries, 8.4 per cent in the USA and 8.0 per cent in England, but the incidence in geldings in the USA (10 per cent) was much higher than in England (1.5 per cent). A more excitable than average temperament was reported in 71 per cent of the horses with the condition, and most cases occurred after a game (chukka) in which the horse was perceived to be not fit enough for the level of play demanded. Sixty-four per cent of the cases occurred early in the season and on average each episode resulted in the loss of 7.6 training days.     

Elastase-producing microorganisms in horse lungs: their possible role in the pathogenesis of chronic pulmonary disease in the horse

Seventeen out of 21 horses had pulmonary microbial organisms which reached considerable numbers in seven cases. Elastase-producing microorganisms from the environment (Streptomyces species and to a lesser extent Bacillus species) constituted 22 per cent to 99 per cent (mean 79 per cent) of the total growth. There was a considerable number of microorganisms with in vitro-produced elastases which were not or only slightly affected by horse serum. There was no correlation between numbers of organisms and pulmonary histopathological findings thus the significance of these microorganisms in the pathogenesis of alveolar emphysema is unknown. The growth of a strain of Streptomyces collinus/diastatochromogus isolated from the lungs was suppressed by fresh horse serum but not by decomplemented horse serum. Complement activation in response to this organism could contribute to airway inflammation through the production of mediators.     

Field study of the prevalence of lameness in horses with back problems

A population of 805 horses (70 per cent dressage, 20 per cent show jumpers and 10 per cent trotters) with orthopaedic problems was examined for signs of lameness and back problems, irrespective of their original complaints. In the horses with a back problem the prevalence of lameness was 74 per cent, and back problems were diagnosed in 32 per cent of the lame horses. These percentages were significantly higher than those recorded in a control population of 399 horses, of which 20 per cent were lame and 12 per cent had back problems. In the group of horses with orthopaedic problems there was a strong association between lameness and back problems and, in particular, there was a high prevalence of lameness among the horses with back problems.     

Osteochondritis dissecans of the tarsocrural joint: results of treatment with arthroscopic surgery

The technique and results of arthroscopic surgery for the treatment of osteochondritis dissecans in 318 tarsocrural joints in 225 horses are reported. Of the 225 horses, 154 were racehorses or intended for racing. Arthroscopic surgery was an effective technique for treating osteochondritis dissecans of the tarsocrural joint. The overall functional ability and cosmetic appearance of the limbs were excellent. Post surgical follow-up information was obtained for 183 horses, of which 140 (76.5 per cent) raced successfully or performed their intended use following surgery. Of the remaining 43, 11 were considered to still have a tarsocrural joint problem, 19 developed other problems precluding successful performance, eight were considered poor racehorses without any lameness problems identified, three were killed because of septic arthritis and two died from other causes. There was no significant effect of age, sex or limb involvement on the outcome. The size of the intermediate ridge lesions had no effect on prognosis but the presence of degenerative or erosive changes in the articular cartilage significantly decreased the prognosis. The synovial effusion resolved in 117/131 racehorse joints (89.3 per cent) and 64 of 86 non-racehorse joints (74.4 per cent) with follow-up. The outcome for synovial fluid resolution was significantly inferior for lesions of the lateral trochlear ridge of the talus or medial malleolus of the tibia compared to distal intermediate ridge lesions. There was no significant relationship between resolution of effusion and successful performance outcome.     

An epidemiological study of summer eczema in Icelandic horses in Norway

A survey of summer eczema was conducted on 391 Icelandic horses in Norway. The study showed a prevalence of summer eczema of 17.6 per cent in the horses investigated. Icelandic horses born in Norway where shown to be less affected with summer eczema than imported horses, 8.2 per cent and 26.9 per cent respectively (P less than 0.001). There was no difference in the prevalence of summer eczema relative to gender or colour of the horse. The number of horses affected with summer eczema rose with increasing age and the number of years which had elapsed since importation. On average, Icelandic horses born in Norway developed summer eczema at the age of 5.3 years. The onset of disease for imported horses was, on average, 4.1 years after importation. The study also revealed that a significantly greater number of horses imported from Iceland to Norway during the period October to April, which has a minimal or low activity of insects (32.3 per cent), had developed summer eczema, compared with horses imported during the period May to September, when insects are more active (16.7 per cent), (P = 0.044). Horses with summer eczema were shown to be significantly more affected by respiratory disease than non-affected horses (P = 0.0086). The most common sites and clinical signs of summer eczema are also described.     

Sentinel practice-based survey of the management and health of horses in northern Britain.

Details of the management, feeding, level of activity and routine health care of horses in Scotland and the five northernmost counties in England were recorded through a stratified random sample of horse owners who had responded to a previous survey. Sixty-eight per cent of the horses were kept where their owners resided, and 32 per cent were kept away from the owner's home. More than 99 per cent were turned out to grazing for at least part of the year and 81 per cent were stabled for at least part of the time, most commonly bedded on straw (50 per cent) or shavings (34 per cent). Hay was fed to 87 per cent, sugar beet pulp to 64 per cent and commercially prepared concentrate mixes to 60 per cent of the horses. Hacking was the most popular activity (52 per cent of horses) followed by riding/pony club events (28 per cent) and showing (21 per cent). The majority of the horses were involved in more than one activity. There were an estimated 0.88 veterinary visits per horse per year and 29 per cent of the horses were reported to suffer from at least one permanent or recurrent health disorder. The median annual numbers of administrations of vaccines (influenza and tetanus) and anthelmintics were one and seven respectively per horse, and each horse was shod a median seven times. There were significant differences in the management of horses kept in different types of premises and in areas of different human population density.