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71.
72.
Reasons for performing study: This study investigated the use of a wireless ambulatory capsule (WAC; SmartPill® pH.p GI Monitoring System) to determine WAC‐gastric emptying time (GET) in ponies. Objectives: To measure WAC‐GET and compare it to those findings with GET assessed by nuclear scintigraphy (S‐GET). Hypothesis: WAC‐GET will be slower than S‐GET, but will be significantly correlated. Methods: Seven healthy adult mixed‐breed pony mares were used in this study. Feed was withheld for 12 h prior to the WAC administration. After administration, a complete‐feed diet was fed to allow the WAC to pass into the stomach. Luminal pH, temperature and pressure were collected by a modified receiver secured to the pony. Once the pH reached a value of ≥8.0, it was determined that gastric emptying had occurred, and ponies were fed grass hay. After 5 days, data were downloaded and analysed using proprietary software. During the second period of the study, after at least 2 weeks, 4 of the ponies underwent a standard S‐GET test. Results: The WAC was successfully administered, and data were collected from all ponies. The mean percentage of data packets collected by the receiver was 84.9 ± 3.51% (range 66.8–95.1%). Mean WAC‐GET was 7.38 h (range 0.15–46.65 h). Mean gastric pH was 4.75 (range 2.07–6.99). Mean small intestinal transit time was 4.6 h. The mean pH for the small intestine was 8.0. The mean S‐GET time (in hours) when 10% of the radioactive feed is present in the stomach (T‐90%) was 2.3 h. The S‐GET did not correlate significantly with the WAC‐GET. Conclusions and potential relevance: The WAC was safely administered to ponies, and data were collected using a modified receiver. The WAC‐GET varied considerably between ponies, but was ≤3 h in 5 of the 6 ponies. The WAC used in this study provided a noninvasive technique that produced novel information about the pony gastrointestinal tract, but owing to the substantial variability in GET values and long transit time it may not be a reliable clinical tool at this time.  相似文献   
73.
In helical hydro-computed tomography (helical hydro-CT), water is used as a neutral luminal contrast medium together with intravenous iodine contrast medium for the diagnosis and staging of human gastric neoplasia. We evaluated the feasibility of helical hydro-CT in 11 healthy animals (nine dogs and two cats). Adequate uniform gastric distension was obtained with 30 ml water/kg body weight. Fourteen client-owned dogs and four cats with suspected or diagnosed gastric neoplasia then underwent helical hydro-CT followed by intravenous contrast medium administration. Focal thickening with moderate contrast enhancement was found in 10 dogs and 3 cats. The extent of the lesion was assessed easily in all these patients. Three dogs and one cat had a normal stomach wall. One dog had multifocal thickening of the antrum but no histopathologic diagnosis was made. Helical hydro-CT, followed by intravenous contrast medium administration, is a simple technique for assessing the stomach wall.  相似文献   
74.
75.
Objective  To investigate the effect of pre-anaesthetic fasting time and variety of food on gastric content (GC) volume and pH in dogs.
Study design  Randomized, cross-over, prospective experimental study.
Animals  Fifteen mongrel dogs (nine females and six males 1–4 years old, weighing 10–24.5 kg).
Methods  Each dog received the same seven treatments in random order: dry food 3 hours before anaesthesia (BA) (treatment 3D), canned food (half daily rate) 3 hours BA (treatment 3C), 0% fat cow milk 3 hours BA (treatment 3M), dry food 10 hours BA (treatment 10D), canned food 10 hours BA (treatment 10C), low fat canned food 10 hours BA (treatment 10F) and low protein canned food 10 hours BA (treatment 10P). All animals were pre-medicated with propionyl promazine and anaesthesia was induced with thiopental sodium and maintained with halothane. GC was aspirated using an orogastric catheter and its volume and pH were measured.
Results  Treatment 10F had significantly lower GC pH than all the 3-hour treatments. Treatments 10D and 10P had significantly lower pH than treatments 3D and 3C. Treatment 3M had significantly lower pH than the other 3-hour treatments. Treatment 3D had significantly greater gastric volume than treatments 3M, 10C, 10F and 10P.
Conclusions and clinical relevance  Canned food at half the daily rate administered 3 hours before anaesthesia did not increase significantly the GC volume compared to the other types of food used. The GC pH was also high. This type of food fed 3 hours before induction of anaesthesia may be of benefit in reduction of the incidence of gastro-oesophageal reflux during anaesthesia in dogs.  相似文献   
76.
Objective – To determine whether myoglobin (Mb) is a useful prognostic indicator for outcome and to investigate any relationship between Mb and mortality in dogs with gastric dilatation‐volvulus (GDV). Design – Prospective study. Setting – Veterinary teaching hospital. Animals – Seventy‐two dogs with GDV. Interventions – Blood sampling. Measurements and Main Results – Mb levels were measured at the time of diagnosis (Mbt0), 24 hours (Mbt1), and 48 hours (Mbt2) after signs of GDV were recognized. Fifty‐seven dogs survived (group I) and 15 dogs did not survive (group II). Mb t0 differed significantly between groups (P=0.04). Mbt0 in group I ranged from <30 to >700 ng/mL (n=57, median 74 ng/mL), and in group II from 34 to >700 ng/mL (n=15, median 238 ng/mL). Analysis of a receiver operating characteristic curve of Mbt0 suggested that the best single cutpoint would be 168 ng/mL (sensitivity 60.0%, specificity 84.2%). Fifty percent of dogs with Mbt0>168 ng/mL were euthanized, while 88.9% with Mbt0<168 ng/mL survived. Mbt1 and Mbt2 differed significantly between groups I and II. Mbt1 in group I ranged from 32 to >700 ng/mL (n=55, median 123 ng/mL), and Mbt1 in group II ranged from 131 to 643 ng/mL (n=7, median 343 ng/mL) (P=0.006). Mbt2 in group I ranged from 30 to 597 ng/mL (n=54, median 101 ng/mL), and in group II from 141 to >700 ng/mL (n=8, median 203 ng/mL) (P=0.02). Conclusions – In this study, Mbt0 is a moderately sensitive and specific prognostic indicator. Almost 90% of the dogs below the cutpoint survived to discharge, whereas 50% with Mbt0 above the cutpoint did not survive.  相似文献   
77.
Retrospectively, 243 dogs with radiographic evidence of gastric dilatation-volvulus (GDV) were studied for radiographic signs of pneumatosis (intramural gas), pneumoperitoneum, splenomegaly, and severity of gastric distention. The sensitivity, specificity, and predictive value of these imaging signs as predictors of gastric wall necrosis, as determined by visual inspection at surgery or necropsy, were determined. The sensitivity and specificity of gastric pneumatosis were 14.1% and 92.7%, respectively. The prevalence of gastric wall necrosis was 26.6%. The positive and negative predictive values of gastric pneumatosis for predicting gastric necrosis were 40.9% and 74.9%, respectively. Gastric pneumatosis and pneumoperitoneum were identified together in four dogs. Pneumoperitoneum, either alone or in conjunction with pneumatosis, yielded similar results as a test for gastric necrosis. Splenomegaly and severity of gastric distention were insensitive and nonspecific for gastric wall necrosis. Splenomegaly did not predict the need for splenectomy at surgery. Although pneumatosis and pneumoperitoneum are relatively specific signs of gastric wall necrosis, the utility of these signs as a test for gastric necrosis is limited in clinical practice. The significance of pneumatosis should be taken into consideration with previous treatments for gastric decompression, as percutaneous gastric trocharization or orogastric intubation may increase the number of false-positive results.  相似文献   
78.
The pathophysiology, clinical course and therapeutic management of gastric dilatation-volvulus (GDV) in dogs are well known. However, the aetiology remains elusive. Aerophagia has often been put forward as a contributing cause of GDV. The most common clinical sign in dogs with nasal mite (Pneumonyssoides caninum) infection is reversed sneezing, which may result in aerophagia. A prospective one-year necropsy study was conducted. Of 250 dogs, 17 were GDV cases and, of these, 35% had concurrent nasal mite infection compared to 5% in the control population. Multivariate logistic regression analyses performed using the 187 dogs with complete records included nasal mite infection status, age, weight and gender. Nasal mite infection was found to be the most important risk factor for GDV in this study, with an odds ratio and confidence interval of 27.6 (4.8–157.5). Other risk factors that were marginally significant included weight and age with odds ratios of 1.08 (1.02–1.13) and 1.37 (1.04–1.79), respectively. Gender was not found to be a significant risk factor for GDV. This study suggests that nasal mite infection may contribute to the development of GDV in otherwise predisposed dogs.  相似文献   
79.
Equine gastric ulceration syndrome (EGUS) is commonly recognised in Thoroughbred racehorses. Although EGUS has previously been associated with reduced athletic performance, no objective studies have been reported. This case report describes 4 racehorses referred for investigation of poor athletic performance where EGUS was the only abnormal finding during a thorough investigation of all body systems. All horses showed considerable improvement in performance following treatment with omeprazole. Therefore, this is the first report in which evidence is presented suggesting a direct link between EGUS and decreased performance, other causes of poor performance having been excluded.  相似文献   
80.
SUMMARY: Diel successive samplings of Japanese Spanish mackerel Scomberomorus niphonius larvae were conducted throughout 24 h both in the sea and in captivity in order to estimate their daily ration. Using the Elliott and Persson model, the instantaneous gastric evacuation rate was estimated from the depletion of stomach contents (% dry bodyweight) with time during the night for wild fish (3.0–11.5 mm standard length) and from starvation experiments for reared fish (8, 10, and 15 days after hatching (DAH)). Japanese Spanish mackerel is a daylight feeder and exhibited piscivorous habits from first feeding both in the sea and in captivity. Feeding activity peaked at dusk. The estimated daily ration for wild larvae were 111.1 and 127.2% in 1996 and 1997, respectively; and those for reared larvae ranged from 90.6 to 111.7% of dry bodyweight. Based on the estimated value of daily rations for reared fish, the total number of newly hatched red sea bream Pagrus major larvae preyed by a Japanese Spanish mackerel from first feeding (5 DAH) to beginning of juvenile stage (20 DAH) in captivity was calculated to be 1139–1404.  相似文献   
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