SERIAL GASTROINTESTINAL ULTRASONOGRAPHY FOLLOWING EXPLORATORY CELIOTOMY IN NORMAL ADULT PONIES

The objective was to characterize ultrasonographic changes in bowel wall thickness, contractility, degree of distension, luminal contents, and peritoneal fluid associated with exploratory celiotomy in normal ponies. Gastrointestinal ultrasonographic examination was performed in 14 ponies on days 1, 3, 5, and 7 after an exploratory celiotomy. Wall thickness, contractility, degree of distension, and luminal contents were recorded for the duodenum and jejunum. Stomach wall thickness and location, cecal wall thickness, and peritoneal fluid location and character were recorded. Peritoneal fluid was identified most frequently on day 1 (P=0.0005). Duodenal wall thickness was significantly decreased on day 7 compared with days 1, 3, and 5 suggesting inflammatory thickening postoperatively (P=0.005). Stomach wall thickness was decreased on day 1 compared with days 3, 5, and 7 (P=0.03). All measurements, however, were within normal limits. Hypocontractile segments of jejunum were most frequently identified on day 1 (P=0.02) and hypoechoic contents were identified most frequently in the jejunum on day 1 and the duodenum on day 3, suggesting mild functional ileus or enteritis in the early postoperative period. Our findings support that bowel handling during abdominal exploration causes minimal changes in bowel wall thickness, contractility, degree of distension, luminal contents, and peritoneal fluid. This study was performed in ponies without gastrointestinal disease and further studies are necessary in patients.     

Reference Values and Repeatability of Transabdominal Ultrasonographic Gastrointestinal Tract Thickness and Motility in Healthy Donkeys (Equus asinus)

The present study aimed to provide reference ranges for the wall thickness and motility pattern of the gastrointestinal tract from a sample of donkeys (Equus asinus) population using B-mode ultrasonography. In the present study, 30 clinically healthy donkeys (Equus asinus) (15 males and 15 females), aged 2–20 year old and weighed 100–280 kg were randomly selected for B-mode ultrasonographic scanning of the abdomen. The wall thickness of the stomach, duodenum, jejunum, left colon, right colon, and cecum was assessed. Moreover, the motility pattern of the duodenum, jejunum, left colon, right colon, and cecum was evaluated over a period of 3 minutes. Abdominal ultrasonographic scanning of the gastrointestinal tract of healthy donkeys explored that the stomach, duodenum, jejunum, left colon, right colon, and cecum could be visualized easily. The wall thickness of the stomach, duodenum, jejunum, left colon, right colon, and cecum was 7.0 ± 0.9 mm, 3.3 ± 1.0 mm, 5.4 ± 0.6 mm, 5.1 ± 0.5 mm, 5.4 ± 0.5 mm, and 5.4 ± 0.6 mm, respectively. The thickest part of the gastrointestinal tract is the stomach, whereas the thinnest part is the duodenum. The motility pattern of the duodenum, jejunum, left colon, right colon, and cecum was 7.7 ± 1.3 contractions/3 minutes, 6.9 ± 1.1 contractions/3 minutes, 4.1 ± 1.2 contractions/3 minutes, 5.5 ± 1.3 contractions/3 minutes, and 4.0 ± 0.8 contractions/3 minutes, respectively. Both the duodenum and jejunum contractions were significantly higher than that of the left colon, right colon, and cecum. This is the first study reporting the reference values for both the wall thickness and motility pattern of the gastrointestinal tract in healthy donkeys (Equus asinus) in Egypt. Good knowledge of these standard and reference values of the wall thickness and motility pattern of gastrointestinal tract structures represents a step in the early diagnosis of the gastrointestinal disorders, including colic in such animal species.     

TRANSCUTANEOUS ULTRASONOGRAPHIC EVALUATION OF THE AIR-FILLED EQUINE STOMACH AND DUODENUM FOLLOWING GASTROSCOPY

Gastroscopy with air insufflation was performed in 10 ponies, after which a transcutaneous ultrasound examination of the stomach and duodenum was performed immediately and at 1, 2, and 4 h postgastroscopy, and 24 h after feeding. Stomach measurements included the dorsoventral and craniocaudal dimensions, as well as the stomach depth from the skin surface and stomach wall thickness at the different time periods. Gastric wall folding was observed in one pony, becoming most distinct 2–4 h postgastroscopy. An undulating stomach wall was noted in eight other ponies postgastroscopy. These observations appeared to be a response to the deflation of the stomach as the insufflated air was released gradually. Gas was detected in the duodenum after the gastroscopy. The parameters measured were noted to be useful to evaluate the extent of stomach distension due to air or feed. The ultrasonographic appearance of the stomach can, therefore, be altered by gastroscopy and this should be borne in mind when examining horses with suspected gastric disease.     

DUODENAL ULTRASONOGRAPHY IN THE NORMAL ADULT HORSE

Ultrasonography was used to evaluate the duodenum of 6 clinically normal horses. Examinations were performed in horses which each, alternatively, received diets of; 1) concentrates and hay, 2) hay only, or 3) after 36 hours of starvation. The duodenum was constantly visualized just ventral to the right kidney at the 16th and 17th intercostal spaces on a line joining the olecranon and tuber sacrale. Cranial to the 16th intercostal space visibility depended on thickness of interposing liver and lung field interference. Duodenal distensions, contractions and content are described. Starved horses had fewer contractions and distensions than horses on hay, or hay and concentrate diets but the difference was not significant. Duodenal wall thickness ranged from 3–4 mm. Ultrasonographically five layers, corresponding to the mucosal surface, mucosa, submucosa, muscularis propria and serosa, could be identified. A necropsy specimen of the duodenum was evaluated histologically and Ultrasonographically in a water bath for comparison.     

Ultrasonographic characteristics of abdominal and thoracic abscesses in cattle and buffaloes

Six cows and five buffaloes with abdominal and thoracic abscesses were examined clinically and ultrasonographically. There was a wide range of clinical signs and at least 50% of the animals exhibited dull demeanour, anorexia, abdominal pain, recurrent tympany and/or weight loss. Three cases of abdominal abscesses were imaged in the left ventral abdomen between the rumen and abdominal wall, two cases were imaged at the xiphoid cartilage near the reticular wall and one case was imaged on the right ventral abdomen between the jejunum and right abdominal wall. Four cases of thoracic abscesses were imaged in the third intercostal space on the left side; however, one case of abscess was imaged in the fourth intercostal space, also on the left side. The content of the abscess was echogenic in eight animals and anechoic in three. In three animals, the content of the abscess was partitioned by echogenic septae. In two cows, the echogenic content of the abscess was surrounded by a narrow rim of anechoic fluid. The diameters of the abscesses were 5-10 cm in three cows, 11-15 cm in seven cows and >15 cm in one cow. In every case, the diagnosis was confirmed by centesis and aspiration of the abscess, which yielded purulent material. There were biochemical data of hypoalbuminaemia and hyperglobulinaemia and 90% of tested animals had neutrophilia. Five cows were examined at slaughter, where the ultrasonographic diagnosis was confirmed.     

EVALUATION OF THE GASTROINTESTINAL TRACT IN DOGS USING COMPUTED TOMOGRAPHY

Abdominal computed tomography (CT) studies of 19 dogs with no history or clinical signs of gastrointestinal disease, and two dogs with a histological diagnosis of gastrointestinal neoplasia were examined retrospectively. Gastrointestinal segments were evaluated subjectively for conspicuity, contrast enhancement, and wall layering after contrast medium administration. In dogs without gastrointestinal disease, there were 62.8% of gastrointestinal segments (serosa to serosa) and 77.7% of gastrointestinal walls (serosa to mucosa) visualized. Wall layering on postcontrast images was seen in 21.8% of gastrointestinal segments. There was significant association between gastrointestinal diameter and wall thickness. There was significant association between weight and gastrointestinal wall thickness in the following regions: gastric fundus, gastric body, gastric pylorus, gastric pyloric antrum, duodenal cranial flexure, jejunum and ascending colon, and between patient weight and gastrointestinal diameter in cranial duodenal flexure, descending duodenum, transverse duodenum, ascending duodenum, and jejunum. Measurements acquired from CT studies correlated well with previously published normal reference ranges for radiographic and ultrasonographic studies. Gastrointestinal neoplasia, diagnosed in two dogs, had a gastrointestinal wall thickness greater than the range of the dogs without gastrointestinal disease. Computed tomography offers identification of the gastrointestinal tract segments in dogs, allows for evaluation of gastrointestinal diameter and aids in investigation of gastrointestinal wall thickness.     

Computed tomographic findings of the gastrointestinal tract in rabbits

BackgroundGastrointestinal (GI) diseases are common in rabbits. Although diagnostic imaging studies can assist clinicians in selecting therapeutic approaches, there are few reports of advanced imaging findings in normal rabbits. Computed tomography (CT) is recognized as a useful tool in dogs and cats, but there are few reports of normal findings on multidetector computed tomography (MDTC) in rabbits. The goals of this study are to describe the CT anatomic imaging appearance of the GI tract and their normal variation in healthy pet rabbits and to obtain the normal wall thickness measurements of normal GI tract structures.MethodsTwenty-three rabbits were scanned under general anesthesia and the CT abdominal images were analyzed by two experienced radiologists. Location and size of the major GI organs and structures were determined, and wall thickness of the stomach, small and large intestines were measured, including the interobserver agreement. Statistical analysis of quantitative and qualitative variables was performed.ResultsWall thickness values were established for the different parts of the stomach (cardia: 3.4 ± 0.4mm; fundus: 1.4 ± 0.2mm; body: 1.4 ± 0.1mm; pylorus: 2.9 ± 0.5mm), small intestines (duodenum: 1.4 ± 0.1mm; jejunum: 1.2 ± 0.1mm; ileum: 1.4 ± 0.1mm), and large intestines (cecum: 1.2 ± 0.1mm; colon ascending: 1.4 ± 0.3 mm and descending: 1.3 ± 0.3mm). When distended the stomach did not extend beyond the caudal limits of the L2 vertebra. The cecum occupied the ventral abdominal region from T12/T13 to L7/S1, the sacculus rotundus was identified in 11 of the 23 rabbits. The sacculus rotundus and vermiform cecal appendix were identified only in rabbits with mild large intestinal distension.Conclusions and clinical relevanceIt was possible to use CT to evaluate the different portions of the GI tract that are not normally readily visible on radiographs and ultrasound (US). Normal wall thickness values of the different portion of the GI tract were stablished. These results provide new and important reference values for CT studies in normal pet rabbits and provide data for further studies in rabbits with GI diseases.     

Binding of radiolabeled porcine motilin and erythromycin lactobionate to smooth muscle membranes in various segments of the equine gastrointestinal tract

OBJECTIVE: To identify and characterize motilin receptors in equine duodenum, jejunum, cecum, and large colon and to determine whether erythromycin lactobionate competes with porcine motilin for binding to these receptors. SAMPLE POPULATION: Specimens of various segments of the intestinal tracts of 4 adult horses euthanatized for reasons unrelated to gastrointestinal tract disease. PROCEDURE: Cellular membranes were prepared from smooth muscle tissues of the duodenum, jejunum, pelvic flexure, and cecum. Affinity and distribution of motilin binding on membrane preparations were determined by use of 125I-labeled synthetic porcine motilin. Displacement studies were used to investigate competition between 125I-labeled synthetic porcine motilin and erythromycin lactobionate for binding to motilin receptors in various segments of bowel. RESULTS: Affinity of 125I-labeled synthetic porcine motilin for the equine motilin receptor was estimated to be 6.1nM. A significantly higher number of motilin receptors was found in the duodenum than in the pelvic flexure and cecum. The jejunum had a significantly higher number of motilin receptors than the cecum. Erythromycin lactobionate displacement of 125I-labeled porcine motilin from the equine motilin receptor did not differ significantly among various segments of bowel. CONCLUSIONS AND CLINICAL RELEVANCE: Motilin receptors were found in the duodenum, jejunum, pelvic flexure, and cecum of horses. The highest number of motilin receptors was in the duodenum, and it decreased in more distal segments of bowel. Erythromycin lactobionate competed with motilin binding in the equine gastrointestinal tract. This suggests that 1 of the prokinetic actions of erythromycin in horses is likely to be secondary to binding on motilin receptors.     

NORMAL CANINE PEDIATRIC GASTROINTESTINAL ULTRASONOGRAPHY

The normal sonographic appearance of the adult canine gastrointestinal tract has been described. Interpretation of abdominal ultrasonographic findings in puppies is difficult due to the lack of information on normal ultrasonographic findings. The gastrointestinal tract, jejunal lymph node size and the presence and appearance of abdominal fluid were investigated in 23 normal, 7–12-week-old Beagle puppies. The duodenal wall thickness was greater than in other parts of the gastrointestinal tract (mean 3.8 ± standard deviation [SD] 5 mm, range 3.2–4.8 mm). The mean stomach wall thickness was 2.7 ± SD 0.4 mm (range 2.2–3.7 mm), the mean jejunal wall thickness was 2.5 ± SD 0.5 mm (range 1.2–3.4 mm), and the mean colonic wall thickness was 1.3 ± SD 0.3 mm (range 0.7–2.0 mm). In addition, mean duodenal and jejunal mucosal layer thicknesses measured 2.7 ± SD 0.5 mm (range 2.0–3.8 mm) and 1.5 ± SD 0.4 mm (range 0.6–2.5 mm), respectively. Homogenous, hypoechoic jejunal lymph nodes were easily found and the mean thickness was 7.1 ± SD 2.2 mm (range 1.5–12.5 mm). A mild amount of anechoic free peritoneal fluid was present in all puppies.     

ULTRASONOGRAPHIC APPEARANCE OF CANINE PARVOVIRAL ENTERITIS IN PUPPIES

The ultrasonographic appearance of the gastrointestinal tract of puppies suffering from parvoviral enteritis was characterized. Forty puppies between 6 and 24 weeks of age with confirmed canine parvoviral enteritis were examined ultrasonographically within 24 h of admission. Sonographic findings included fluid‐filled small intestines in 92.5% of subjects, and stomach and colon in 80% and 62.5% of subjects, respectively. Generalized atony was present in 30 subjects and weak peristaltic contractions indicative of functional ileus observed in the remaining 10 subjects. The duodenal and jejunal mucosal layer thicknesses were significantly reduced when compared with normal puppies with mean duodenal mucosal layer measuring 1.7 mm and jejunal mucosal layer 1.0 mm. Additionally, a mucosal layer with diffuse hyperechoic speckles was seen in the duodenum (15% of subjects) and the jejunum (50% of subjects). The luminal surface of the duodenal mucosa was irregular in 22.5% of subjects and the jejunal mucosa in 42.5% of subjects. In all of these subjects, changes were accompanied by generalized indistinct wall layering. Small intestinal corrugations were seen within the duodenum in 35% of subjects and within the jejunum in 7.5%. A mild amount of anechoic free peritoneal fluid was observed in 26 subjects and was considered within normal limits and a moderate amount of anechoic free peritoneal fluid was observed in six subjects. The jejunal lymph node size was within normal limits. None of the above changes are pathognomonic for canine parvoviral enteritis but finding them in combination is highly suggestive.     

Ultrasonography of the gastrointestinal tract of toco toucans (Ramphastos toco)

Baseline data for wall thickness in healthy toucans can be used to diagnose disease in sick individuals. This study aimed to evaluate the use of ultrasonography for the examination of the gastrointestinal tract of healthy toco toucans (Ramphastos toco). Ten non-anaesthetized healthy adult toco toucans were evaluated. Food was withheld for 3 h prior to the ultrasound examination. Longitudinal and transverse images of the gastrointestinal tract were obtained using ventromedian cranial and ventromedian caudal approaches to evaluate the morphology and stratification. The wall thickness of the sections was measured: proventriculus and ventriculus, duodenum, jejunum/ileum, and cloaca. Additionally, the thickness of the mucosal layer of the duodenum and jejunum/ileum was also measured. Subsequently, the ratios of the duodenal wall thickness to the duodenal mucosa layer and the total wall thickness of the jejunum/ileum to the jejunum/ileum layer mucosa were stablished. The wall thickness of the proventriculus was significantly higher than the wall thickness of ventriculus. The wall thickness of the duodenum was significantly higher than the wall thickness of jejunum/ileum. The mean ratios of the duodenal wall thickness to the duodenal mucosa layer and the wall thickness of the jejunum/ileum to the jejunum/ileum layer were 83.15% and 80.07%, respectively. In conclusion, it was possible to assess the stomach and intestines using ultrasound examination in healthy toco toucans, due to their medium body size and no interference by surrounding air sacs.     

Ultrasonographic examination of the spleen in 30 goats

The ultrasonographic appearance, location and size of the spleen in 30 healthy female Saanen goats are described. The intercostal spaces of the left thoracic wall were scanned with a 5.0 MHz linear transducer in standing goats. The appearance of the splenic parenchyma, the position of the ultrasonographically visible dorsal and ventral margins of the spleen and the distance between them, the thickness of the spleen and the diameter of the splenic vessels were determined. The spleen could be visualised in at least one examination position and it always lay between the rumen and abdominal wall. The spleen bordered the lung dorsally and was located adjacent to the left abdominal wall in the last intercostal space and area immediately caudal to the last rib. The spleen had an echogenic capsule, and its parenchyma showed a homogenous fine echotexture / echo pattern throughout the whole visible part of the spleen. The splenic vessels were seen within the parenchyma. The visible dorsal margin of the spleen ran from cranioventral to caudodorsal. The distance from the dorsal margin of the spleen to the midline of the back was greatest in the 8th intercostal space (19.7 ± 4.19 cm) and smallest in the region immediately caudal to the last rib (7.0 ± 1.07 cm). The size of the spleen was smallest in the 8th intercostal space (3.1 ± 1.24 cm) and greatest in the 11th intercostal space (8.7 ± 2.78 cm). The thickness of the spleen ranged from 2.2 ± 1.14 cm caudal to the last rib to 6.4 ± 1.78 cm in the 11th intercostal space.     

REPEATABILITY AND REPRODUCIBILITY OF TRANSABDOMINAL ULTRASONOGRAPHIC INTESTINAL WALL THICKNESS MEASUREMENTS IN THOROUGHBRED HORSES

The aims of this study were to assess the repeatability and reproducibility of transabdominal ultrasonography to assess intestinal wall thickness in adult Thoroughbred horses (n=8). Ultrasonographic cineloops were captured by one examiner from each horse for five consecutive days. During each examination at least three cineloops were obtained for five different intestinal tract locations. Measurements were performed by three separate observers to assess reproducibility and measured on three separate occasions by three observers to evaluate short‐term repeatability. The repeatability of measurements from the duodenum (0.3 ± 0.04 cm), jejunum (0.29 ± 0.05 cm), ventral colon (0.37 ± 0.01 cm), and cecum (0.42 ± 0.03 cm) were good ( P >0.291). The reproducibility of measurements from the duodenum, jejunum, and ventral colon were good ( P >0.394). Reproducibility of measurement of the cecal wall was inadequate ( P =0.01), although the maximum difference between observers was 0.07 cm. It was possible to image all areas on all days, with the exception of the duodenum, which could not be imaged in one horse, on 1 day. Equine intestinal wall measurements are therefore repeatable and reproducible with the exception of reproducibility of the measurements of cecal wall. Although an accepted clinical technique, measurement of cecal wall thickness from intestinal ultrasound images in a clinical setting must be interpreted with care.     

Serum Levels of Type III Procollagen Peptide in Equidae before and after Intestinal Ischemia

Serum levels of type III procollagen peptide (P-III-P) were measured by radioimmunoassay in clinically normal adult ponies (n = 15) and horses (n = 10). The mean serum levels of P-III-P from the ponies, 10.4 +/- 2.9 (SD) ng/mL, and the horses, 12.2 +/- 2.6 (SD) ng/mL, were not significantly different. Segments of jejunum were made ischemic to induce fibrous peritoneal adhesions in two ponies, and serum P-III-P levels were measured on days 4, 5, 7, 14, and 21. An exploratory celiotomy on day 21 revealed that the ischemic injury had induced fibrosis of the mesentery and bowel, but no adhesions had formed. The fibrotic mesentery contained type III collagen. The highest mean serum level of P-III-P, 23.0 +/- 3.5 (SD) ng/mL on day 7, was more than 4 SD above the mean from the normal ponies. There was a significant difference in the serum P-III-P levels in the ponies on days 0 (7.1 +/- 1.6 ng/mL) and 7 (23.0 +/- 3.5 ng/mL). Serum levels of P-III-P may be useful to study fibrosis associated with intestinal ischemia.     

Respiratory muscle perfusion in ponies during prolonged submaximal exercise in thermoneutral environment.

Distribution of blood flow among various respiratory muscles was examined in 8 healthy ponies during submaximal exercise lasting 30 minutes, using radionuclide labeled 15-microns diameter microspheres injected into the left ventricle. From the resting values (40 +/- 2 beats/min; 37.3 +/- 0.2 C), heart rate and pulmonary arterial blood temperature increased significantly at 5 (152 +/- 8 beats/min; 38.6 +/- 0.2 C), 15 (169 +/- 6 beats/min; 39.8 +/- 0.2 C), and 26 (186 +/- 8 beats/min; 40.8 +/- 0.2 C) minutes of exertion, and the ponies sweated profusely. Mean aortic pressure also increased progressively as exercise duration increased. Blood flow increased significantly with exercise in all respiratory muscles. Among inspiratory muscles, perfusion was greatest in the diaphragm and ventral serratus, compared with external intercostal, dorsal serratus, and scalenus muscles. Among expiratory muscles, blood flow in the internal abdominal oblique muscle was greatest, followed by that in internal intercostal and transverse thoracic muscles, in which the flow values remained similar. The remaining 3 abdominal muscles had similar blood flow, but these values were less than that in the internal intercostal, transverse thoracic, and internal abdominal oblique muscles. Blood flow values for all inspiratory and expiratory muscles remained similar for the 5 and 15 minutes of exertion. However, at 26 minutes, blood flow had increased further in the diaphragm, external intercostal, internal intercostal, transverse thoracic, and the external abdominal oblique muscle as vascular resistance decreased. On the basis of our findings, all respiratory muscles were activated during submaximal exercise and their perfusion had marked heterogeneity.(ABSTRACT TRUNCATED AT 250 WORDS)     

Ultrasonography of the spleen in 50 healthy cows

This paper describes the ultrasonographic appearance, location and size of the spleen in 50 healthy commercial milk cows destined for slaughter. The intercostal spaces of the left thoracic wall were scanned with a 3.5 MHz linear transducer. In each intercostal space, the appearance of the splenic parenchyma, the dorsal and ventral margins and the distance between them, and the diameter of the splenic vessels were recorded. The spleen was seen in intercostal spaces 7-12. It was 2.0-5.0 cm thick, and tapered ventrally. The splenic capsule appeared as an echogenic line. The splenic parenchyma consisted of numerous small regularly spaced echoes, and vessels within the parenchyma appeared as anechoic round to oval or elongated images. The long axis was oblique, running caudodorsal to cranioventral. The distance from the dorsal margin of the spleen to the midline of the back was greatest in the 7th intercostal space (60.9+/-6.81) and smallest in the 12th intercostal space (12.7+/-2.85 cm). The extent of the spleen was greatest in the 8th intercostal space (24.9+/-10.77 cm) and smallest in the 12th intercostal space (9.5+/-5.38 cm). The mean diameter of the splenic vessels ranged from 0.66+/-0.28 to 0.90+/-0.65 cm, depending on the intercostal space scanned. Ultrasonography of the spleen in healthy cows provides information that can be used as a reference when examining cattle with suspected splenic disease.     

Evaluation of gastrointestinal activity patterns in healthy horses using B mode and Doppler ultrasonography

Healthy adult horses were examined by using transabdominal ultrasonography to quantitatively and qualitatively evaluate activity of the jejunum, cecum, and colon with B mode and Doppler techniques. Doppler ultrasound was used to assess jejunal peristaltic activity. Examinations were performed on multiple occasions under imposed colic evaluation conditions, including fasting, nasogastric intubation, and xylazine sedation. In fasted horses, jejunal visibility was increased and jejunal, cecal, and colonic activity was decreased. The stomach was displaced ventrally and was visualized ventral to the costochondral junction. Xylazine sedation in fed horses had minimal effects; however, in fasted horses, xylazine significantly decreased jejunal and cecal activity. Nasogastric intubation in fasted horses had no observable effects on activity, but moved the stomach dorsally. B mode and Doppler jejunal activity were strongly correlated. Prior feeding and sedation status need to be considered when interpreting the results of equine abdominal ultrasound examinations. Doppler techniques may be useful for assessing jejunal activity.     

Serovar-specific real-time quantitative detection of Salmonella enteritidis in the gastrointestinal tract of ducks after oral challenge

The objective of this study was to identify and understand the regular distribution pattern and primary penetration site for Salmonella Enteritidis (SE) in the gastrointestinal tract of ducks. An assay based on the serovar-specific DNA sequence of SE from GenBank, a serovar-specific real-time, fluorescence-based quantitative polymerase chain reaction, was developed for the detection of SE. We used this assay to detect genomic DNA of SE in the blood and gastrointestinal tract, including duodenum, jejunum, ileum, cecum, rectum, esophagus, stomach muscularis, and stomach glandularis, from ducks after oral challenge at different time points. The results showed that SE was consistently detected in all segments of the gastrointestinal tract. The jejunum and ileum were positive 8 hr postinoculation (PI). The organism was detected in blood 12 hr PI, while the final organ to show a positive result was the stomach at 24 hr PI. The copy number of SE DNA in each tissue reached a peak at 24-36 hr PI, with the jejunum, ileum, and cecum containing high concentrations of SE, whereas the blood, duodenum, rectum, stomach, and esophagus had low concentrations. SE populations began to decrease and were not detectable at 2 days PI, but were still present up to 9 days PI in the jejunum, ileum, and cecum without causing apparent symptoms. By 3 days PI the cecum had significantly higher numbers of SE than any of the other areas (P < 0.01), and this appeared to reflect its function as a repository for SE. In conclusion, the results provided significant data for understanding the life cycle of SE in the gastrointestinal tract and showed that the jejunum, ileum, and cecum were the primary sites of invasion in normal ducks after oral challenge. This study will help to understand the mechanisms of action of SE infection in vivo.     

Strangulating obstruction caused by intestinal herniation through the proximal aspect of the cecocolic fold in 9 horses

OBJECTIVE: To report the clinical and surgical findings and outcome for horses with strangulating obstruction caused by herniation through the proximal aspect of the cecocolic fold. STUDY DESIGN: Retrospective study. ANIMALS: Nine horses. METHODS: Medical records were reviewed for clinical signs, surgical findings and technique, and outcome. Cadaver ponies and necropsy specimens were also used to study the regional anatomy of the cecocolic fold. RESULTS: The ileum and distal jejunum were strangulated in 8 horses, whereas in 1 horse the small intestine and the left ascending colons were incarcerated in a rent in the cecocolic fold. Two horses were euthanatized at surgery, 6 horses had a small intestinal resection (mean length, 3 m; range, 1.5-6.4 m) and an end-to-side jejunocecostomy, and the entrapment was reduced without resection in the horse that had small intestine and ascending colon incarceration; cecocolic fold defects were not closed. One horse was euthanatized 36 hours after surgery because of endotoxemia. Six horses were discharged; 4 were available for long-term follow-up, of which 2 were euthanatized, and 2 were euthanatized 12 and 18 months after surgery because of colic signs. Variations in thickness of the cecocolic fold were observed in specimens obtained from necropsy of other horses and ponies. CONCLUSIONS: Reasons for this defect are unknown, although observed anatomic differences in cecocolic fold thickness may contribute to the development of defects. CLINICAL RELEVANCE: Reduction of the entrapped bowel is easiest when traction is placed on the bowel at a 90 degrees to the base of the cecum. Intestinal incarceration through rents within the proximal part of the cecocolic fold should be considered as a differential diagnosis for strangulating obstruction in horses.     

Serum and peritoneal fluid phosphate concentrations as predictors of major intestinal injury associated with equine colic

To determine the reliability with which inorganic phosphorus (phosphate) concentrations can be used to predict major intestinal injury associated with equine colic, phosphate concentrations were measured in serum, peritoneal fluid, or both from 9 clinically normal adult horses (group A), 37 horses successfully managed medically for signs of abdominal pain (group B), 26 horses with signs of abdominal pain and undergoing exploratory laparotomy without intestinal resection (group C), and 26 horses undergoing intestinal resection or euthanasia for extensive intestinal lesions (group D). Peritoneal fluid phosphate concentration was significantly greater in horses in group D (mean, 4.58 +/- 0.34 mg/dl) than in horses in group A (mean, 2.78 +/- 0.21 mg/dl), group B (mean, 2.92 +/- 0.27 mg/dl), and group C (mean, 2.98 +/- 0.28 mg/dl; P less than or equal to 0.01). Serum phosphate concentration was significantly greater in horses in group D (mean, 3.87 +/- 0.30 mg/dl) than in horses in group A (mean, 2.73 +/- 0.22 mg/dl), group B (mean, 2.80 +/- 0.21 mg/dl), and group C (mean, 2.78 +/- 0.22 mg/dl); P less than or equal to 0.05). There was significant (P less than or equal to 0.001) correlation between serum and peritoneal fluid phosphate concentrations within each group and when pairs from all groups were pooled. When peritoneal fluid phosphate concentrations exceeded 3.6 mg/dl, intestinal lesions requiring resection or euthanasia were predicted with sensitivity of 77% and specificity of 76%. When serum phosphate concentrations exceeded 3.3 mg/dl, such lesions were predicted with sensitivity of 60% and specificity of 73%.(ABSTRACT TRUNCATED AT 250 WORDS)