摘要:

SummaryCharacteristic motility patterns were seen throughout the gastrointestinal tract in a pony prepared chronically with electromechanical recording devices after developing a simple obstruction of the small intestine. Gross distension of the stomach with fluid produced loss of gastric contractile activity and a chaotic electrogram. These changes were reversed instantaneously when the stomach was decompressed. In the jejunum, proximal to the obstruction, the unique ‘colic motor complex’ was observed with contractions of longer duration arranged in characteristic pulses of activity. The left dorsal colon showed continuous hyperactivity and the small colon remained active. Abnormal motility patterns occurring secondary to a small intestinal obstruction could play a role in the aetiology of small and large intestinal disord

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1989.tb05654.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

SummaryLight microscopy, morphometry and scanning electron microscopy (SEM) were used to examine the mucosal morphology of seven intestinal specimens (three from the small intestine and four from the large intestine) from two horses not subjected to surgery and three horses one year after sham‐operation for colon resection. Qualitative and quantitative evaluation revealed similar morphology for all horses except that the unoperated horses had significantly (P<0.05) fewer goblet cells in the crypts of the large intestine. In the small intestine, SEM demonstrated that villus shape varied and ranged from coned to broad and flat. In the large intestine, SEM of the right ventral and dorsal colon revealed more prominent crypt openings than in the caecum. The small colon contained the most prominent crypt openings with the least variation among horses. In the small intestine, light microscopy and morphometry revealed a greater number of goblet cells and a decreased width to the enterocytes in an aboral direction from the cranial jejunum to the ileum. In the large intestine, the crypt area and crypt depth increased significantly and the intercrypt area decreased significantly in an aboral direction from the caecum to the small colon (P<0.05). In comparison to the normal morphology, horses one year after extensive large colon resection had significantly greater intercrypt area in the caecum and remaining large colo

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1989.tb05655.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

SummaryCisapride and domperidone were both effective in restoring electrical and mechanical activity, coordination between gastric and small intestinal activity cycles and the stomach to anus transit time in three ponies in which post operative ileus was induced experimentally. Cisapride (0.1 mg/kg bodyweight intramuscularly) for three to eight doses prevented idiopathic post operative ileus in 22 clinical cases requiring colic surgery. The only side effects after cisapride were increased bowel sounds and slight, transient sounds of discomfort. No adverse side effects were seen in 16 cases following anastomosis or enterotomy. Cisapride appears safe and effective in the prophylaxis of equine post operative ileus.

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1989.tb05656.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

SummaryGastrin is the only hormone known to stimulate secretion of hydrochloric acid. It also has trophic effects on specific parts of the mucosa of the gastrointestinal tract. Using radioimmunoassay techniques, postprandial serum gastrin and insulin concentrations were measured in six adult horses to establish effects of different diets on gastrin concentrations. Insulin concentrations were measured to provide support to the patterns of gastrin secretion because patterns of insulin secretion were already known. The horses were fed coastal bermuda hay, or twice daily 5 kg of a complete pelleted ration, 5 kg of commercial sweet feed or 5 kg of the sweet feed together with hay. There was little change in serum gastrin or insulin concentrations after feeding hay alone. Rations containing more readily available nutrients (pellets, sweet feed) produced significant increases in postprandial serum gastrin and insulin concentrations. Gastrin concentrations also varied according to the duration of feeding each diet, but this was not seen with insulin. These results indicated that gastrin secretion, and therefore possibly gastric acid secretion, were markedly influenced by dietary composition and duration of feeding a diet. There appeared to be some adaptation of the stomach (gastrin secretion) to changes in diet, but this was not accompanied by indications of adaptation in the endocrine pancreas (insulin secretion).

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1989.tb05657.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

SummaryA reproducible, reversible model of colitis induced in ponie by administering castor oil (2.5 ml/kg bodyweight [bwt]per os) was characterised by abdominal pain, fever, watery diarrhoea, dehydration, hypovolaemia, toxaemia, leucopenia, decreased serum Cl, Na and K levels and metabolic acidosis. The signs were most severe between 24 and 48 h post induction, stabilisation was frequently observed after 72 h, although diarrhoea could persist beyond 96 h. Morphological andin vitrotransport studies (right ventral colon) were conducted on tissues from animals destroyed at 24, 48 and 72 h. In the caecum and colon, surface epithelial disruption and exfoliation from the basement membrane occurred between 24 and 48 h. Early signs of recovery were evident by replenishment of denuded areas with columnar epithelium at 72 h. The crypt epithelium was unaffected throughout the intestinal tract.In vitrotransport studies were consistent with the morphological findings. Decreased Na‐Cl absorption and normal Cl secretion indicated an impaired surface epithelium coincident with an undamaged cryptal epithelium. Increased mucosal permeability was demonstrated by high ionic conductance and large unidirectional isotopic fluxes. Tissue conductance improved during in vitro incubation suggesting epithelial repair after removal of castor oil. Changes in the population and proportion of bacteria in the faeces as diarrhoea ensued were confirmed at necropsy with a predominance ofE. coliandEnterobacter/Klebsiellasp in the large bowel. The experimental induction of castor oil colitis showed many similarities to intestinal endotoxaemia and the secretory type diarrhoea encountered in naturally occurring acute colitis syndromes in horses. The model could prove applicable in studying the pathophysiological mechanisms precipitating such life‐threatening disord

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1989.tb05658.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

SummaryGastroendoscopic examinations were performed on 187 horses, ranging from one to 24 years. Eighty‐seven horses had clinical problems including chronic, recurrent colic for seven or more days (25), one or more episodes of colic within the previous seven days (13), or acute colic (10), diminished appetite (53), poor bodily condition (40), and/or chronic diarrhoea (9). One hundred horses that had no signs of gastrointestinal problems were examined as part of a gastroendoscopic survey. Lesions observed in the squamous fundus, squamous mucosa adjacent to the margo plicatus along the greater curvature, glandular fundus, and the squamous mucosa along the lesser curvature were scored on a scale of 0–4, with 0 representing no lesions and 4 representing the most severe lesions. The mean endoscopic scores for the squamous fundus, margo plicatus and lesser curvature were significantly greater (P<0.001) in horses with clinical signs than those without signs. This was because of the greater number of horses with lesions in the symptomatic group (80/87) compared to those without signs (52/100), and the greater severity of lesions in the horses with clinical signs. Of the horses, 74 were in race training. There was a significantly (P<0.01) greater prevalence and severity of lesions at all sites except the glandular fundus in horses in training compared to those not in training, and in the horses in training with clinical signs (n = 37) compared to those in training without clinical signs (n =

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1989.tb05659.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

SummaryThe pH of the gastric mucosal surface and gastric content was measured in 18 foals (mean age: 20 days) and 27 horses (mean age: 2.9 years) with a pH electrode passed through an endoscope biopsy channel. A reference electrode was attached to a shaved area on the neck. pH Measurements of the gastric mucosal surface at the dorsal squamous fundus (SF), squamous mucosa adjacent to the margo plicatus (MP), glandular fundus (GF) and the fluid or feed contents of the stomach were recorded in duplicate for each animal. In adult horses, the SF pH was greatest (5.46±1.82), with a decreasing pH ventrally toward the MP (4.12±1.62), to the glandular fundic mucosa (3.09±1.90), and fluid contents (2.72±1.86). The differences in pH at each site within the stomach were significant (P<0.05). In foals, mean pH measurement of the SF was 4.88±1.30, the MP was 4.92±1.29, the GF was 2.10±1.45, milk and fluid contents was 1.85±0.53 (six foals), and feed contents was 3.39±1.77 (12 foals). The pH of the SF and MP were significantly greater (P<0.05) than that of feed contents, which was significantly greater (P<0.05) than that of the glandular mucosal surface and fluid contents. The results indicate a dorsal to ventral pH gradient of the gastric mucosal surface in adult horses, and that gastric acid secretion is competent in you

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1989.tb05660.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

SummaryOf 55 horses treated with histamine type 2 (H2) receptor antagonists for gastric ulcers, 32 were examined by gastroendoscopy before and after treatment. Distribution and severity of lesions in the squamous fundus (sf), margo plicatus (mp), glandular fundus (gf), lesser curvature (lc) and cardia (car) were recorded. Severity of the lesions was scored 0–4 (0=no lesions, 4=most severe). On initial examination, lesions were most frequently observed at the mp (28/32) and least frequently observed in the gf (5/32). There was endoscopic confirmation of improvement in lesion scores in each region, although the magnitude of improvement and duration of treatment required to affect total healing varied by region. The mean (± sd) changes in lesion scores in each region of the stomach after treatment were: −1.92 ± 1.43 (sf), −2.27 ± 0.98 (mp), −1.60 ± 0.80 (gf), −1.20 ± 1.81 (lc), and −2.00 ± 1.85 (car). Clinical improvement was noted in 54 of 55 animals, as indicated by decreased frequency of colic episodes, weight gains, and improved appetite. It was concluded that H2antagonists are an effective treatment of gastric ulcers in horses, as determined by endoscopic and cli

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1989.tb05661.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

SummaryThe activity of serum angiotensin converting enzyme (ACE) for healthy horses was 64 ± 13 mUnits/ml.In vitro, equine serum ACE was sensitive to the following inhibitors (IC50): enalapril (570 nM or 215 ng/ml), captopril (190 nM or 41.3 ng/ml), and enalaprilat (6 nM or 2.1 ng/ml). The intravenous (iv) administration of angiotensin I to six healthy horses produced a dose proportional pressor response. The maximal increase in mean arterial pressure over baseline values was 65.6 mmHg at angiotensin I doses of 500 ng/kg bodyweight (bwt). The attenuation of this response to angiotensin I was further demonstrated in a single horse by the prior administration of enalaprilat at an iv dose of 8.71 μg/kg bw

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1989.tb05662.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

SummaryThe purpose of this survey was to identify complications occurring in horses with colic during anaesthesia and recovery from anaesthesia; and to determine any relationships between these complications and drugs used for induction or maintenance of anaesthesia. Two hundred and thirty nine horses were anaesthetised on a total of 250 occasions for colic surgery between January 1985 and May 1987. Of these, 189 recovered from 200 anaesthetic episodes. Most horses received xylazine and guaifenesin with either thiobarbiturate (68 per cent) or ketamine (24 per cent) and anaesthesia was maintained with either halothane (51 per cent), isoflurane (43 per cent), or first halothane then isoflurane (6 per cent). Sixty nine per cent also received an opioid. Hypotension or tachycardia were recorded in 15 and 13 per cent of anaesthesias, respectively. Arterial P02 was less than 13.3 kPa in 17 per cent of 175 anaesthesias. None of these complications was associated with a specific anaesthetic agent. Hypertension was recorded in 11.5 per cent of anaesthesias and occurred more frequently during isoflurane anaesthesia (P<0.05). The mean duration of anaesthesia was 126 mins (range, 50–270 mins), and was not different for horses receiving thiobarbiturate or ketamine, halothane or isoflurane. The time taken to stand after anaesthesia recorded on 149 occasions and was 63 ± 24 mins (range, 15–135 mins). This was not different for the different anaesthetic agents. Horses that were excited or had difficulty standing up during recovery had a significantly longer duration of anaesthesia (165 ± 51 mins) (P<0.05) but no specific anaesthetic agent was involved. Of the 189 horses, 148 (75 per cent) survived and were discharged from the hospital. Horses that did not survive had a significantly increased prevalence of anaesthetic complications, and longer durations of anaest

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1989.tb05663.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY