CONTRAST‐ENHANCED ULTRASOUND OF THE FELINE KIDNEY

Contrast‐enhanced ultrasound offers a noninvasive means of subjectively and quantitatively evaluating renal perfusion in cats with renal disease, or in renal transplant patients. In this study, we characterized the pattern of ultrasonographic contrast enhancement in 16 normal feline kidneys in eight cats using contrast‐enhanced power Doppler and contrast‐enhanced harmonic ultrasound techniques. Mean time to peak contrast enhancement for the whole kidney was longer using contrast‐enhanced harmonic ultrasound (16.8s, SD 4.7s) than contrast‐enhanced power Doppler ultrasound (12.2s, SD 1.8s). The time to peak enhancement for the cortex alone in contrast‐enhanced harmonic ultrasound was 13s (SD 3.2s), and for the renal medulla was 25.5s (SD 8.7s). The half time for washout of contrast agent was 39s (SD 14.5s) for contrast‐enhanced harmonic ultrasound. The pattern of contrast enhancement in these normal feline kidneys can be used as normal reference values for the evaluation of clinical patients. Contrast‐enhanced harmonic ultrasound may allow the differentiation between cortical and medullary perfusion patterns.     

Seasonal changes in a deep‐water fish assemblage in response to monsoon‐generated upwelling events

The coastal shelf of the Gulf of Oman experiences periodic upwelling events during the summer months that are driven by the southwest monsoon. It is unclear what role these events play in the spatial and temporal distribution of the region’s fish assemblage. We carried out trials on two different video techniques to characterize the habitat and fish assemblage along the continental shelf margin near Muscat, Oman. Exploratory surveys with a drift stereo‐video revealed three main habitat types: Sand, Reef and Megabenthos. Three areas were chosen for additional sampling using stereo‐BRUVS (‘baited’ remote underwater‐video systems). On two separate occasions (November 2005 and March 2006) replicate stereo‐BRUVS were deployed in each area stratified by the main habitat types. For each teleost and elasmobranch species encountered on the video, an estimate of total body length and the relative abundance (MaxN_i) was made. The stereo‐BRUVS recorded a wide range of demersal and pelagic teleosts including species of conservation interest such as sharks, rays and groupers. The drift stereo‐video recorded significantly fewer species than the stereo‐BRUVS (N = 15 versus N = 43). Species diversity from the stereo‐BRUVS increased by 96% in March 2006 (N = 41) compared to November 2005 (N = 23), a pattern consistent at all three areas. The structure of the overall fish assemblage (using canonical analysis of principal coordinates analysis) was highly variable both in time and space. There was ample evidence of strong habitat associations, particularly with depth and seasonal shifts in abundance and diversity. We argue the upward migration of oxygen‐depleted water into the shallow depths during the late monsoon displaces the demersal fish community along this coast.     

EXPERT INTERPRETATION COMPENSATES FOR REDUCED IMAGE QUALITY OF CAMERA‐DIGITIZED IMAGES REFERRED TO RADIOLOGISTS

We compared the accuracy of five veterinary radiologists when reading 20 radiographic cases on both analog film and in camera‐digitized format. In addition, we compared the ability of five veterinary radiologists vs. 10 private practice veterinarians to interpret the analog images. Interpretation accuracy was compared using receiver operating characteristic curve analysis. Veterinary radiologists' accuracy did not significantly differ between analog vs. camera‐digitized images (P=0.13) although sensitivity was higher for analog images. Radiologists' interpretation of both digital and analog images was significantly better compared with the private veterinarians (P<0.05).     

Studies of the distribution of yellowing viruses in the sugar beet root crop from 1981 to 1984

Two viruses, beet yellows virus (BYV) and beet mild yellowing virus (BMW), cause yellowing of sugar beet, their principal vector being Myzus persicae. Although the viruses have different properties which are likely to influence their spread within root crops, for the purpose of control they have been treated in the past as one disease. This paper describes the results of a crop survey carried out in co-operation with agricultural staff of British Sugar plc from 1981 to 1984 in which leaves from plants with symptoms of virus yellows were tested by enzyme-linked immunosorbent assay (ELISA) for BYV and BMW. The two viruses differed in their incidence and distribution within the national sugar beet root crop; BMW was the main cause of yellowing and occurred in all parts of the growing region while BYV, which has the more severe effect on yield, was more limited in distribution. The survey located areas in southern East Anglia which are at greatest risk from BYV infection. The possible need to modify control measures depending on which virus threatens to invade the crops is discusssed. A high proportion of leaves visually identified as infected was found to contain neither BYV nor BMYV, emphasizing the difficulties of identifying virus-infected plants by field symptoms.     

Prevalence of and Risk Factors for Postoperative Ileus after Small Intestinal Surgery in Two Hundred and Thirty-Three Horses

Objectives— To determine the incidence of postoperative ileus (POI) in a population of horses after small intestinal surgery and the effect of multiple variables on development of POI.
Study Design— Case series.
Animals— Horses (n=233) aged ≥1 year that had exploratory celiotomy for small intestinal disease that recovered from surgery from 1995 to 2005.
Methods— Sixty-eight variables were collected from medical records (1995–2005) for each horse. POI was defined as nasogastric reflux volume >20 L over 24 hours or >8 L at any single time after surgery.
Results— Twenty-seven percent (64/233) of horses developed POI; 29 of 64 (46%) horses with POI had duodenitis proximal jejunitis (DPJ). When no intestinal resection was required at surgery, excluding horses with DPJ, 15% of horses had POI; 30% horses had POI after intestinal resection. Ten percent of horses had POI for >24 hours. When horses with DPJ were excluded, factors associated with increased risk of POI included high packed cell volume at hospital admission ( P =.024), increasing age ( P =.0004), and length of intestinal resection ( P =.05).
Conclusions— Risk factors for POI in this study were nonspecific although horses with intestinal resection are at higher risk compared with horses without intestinal resection.
Clinical Relevance— Predicting with certainty which cases will develop POI remains elusive.     

The Influence of Body Position on the Blood Gas and Acid-base Status of Halothane-anesithetized Sheep

Eleven adult sheep were divided into three groups. Baseline arterial blood samples were taken with the sheep standing and breathing room air. They were then anesthetized and placed in right (group one), left (group two), or dorsal (group three) recumbency. Arterial blood samples were taken at 30, 60, 90, and 120 minute intervals during anesthesia, and 15 minutes after the discontinuation of halothane in oxygen.
Anesthetic induction resulted in an increase in arterial oxygen (Pao₂) and carbon dioxide (Paco₂) tensions and a decrease in arterial pH (pHa) and base excess (BE). During anesthetic maintenance, no positional effects were noted, and pHa and BE increased in all groups. With the termination of anesthesia and the animals breathing room air, pHa increased, and Pao₂ and Paco, decreased; BE was elevated in group two when compared to group three. Only BE had returned to control values 15 minutes after halothane was discontinued.     

Gastric Myoelectric Activity after Experimental Gastric Dilatation-Volvulus and Tube Gastrostomy in Dogs

Gastric myoelectric activity was measured after experimental gastric dilatation-volvulus (GDV), GDV and tube gastrostomy, or tube gastrostomy in 12 dogs. Gastric myoelectric activity was recorded for 1 hour before (hour 0) and at hours 5, 24, 48, 72, and 96 after surgically induced GDV in six dogs. Three dogs with induced GDV and tube gastrostomy, and three dogs with tube gastrostomy only were also studied at hours 120, 144, and 168. The only significant change in the slow wave appearance or frequency from hours 0 to 48 was bradygastria at hour 5 in all three groups. A relative increase in the mean percentages of dysrhythmia from hours 72 to 168 in the dogs with a tube gastrostomy was caused by increases in tachygastria and arrhythmias. Dogs with GDV and tube gastrostomy had the greatest mean percentages of dysrhythmia, which were significantly more than those in dogs with GDV alone at hours 48, 72 and 96. The mean percentage of spike activity was less than or equal to 31 and varied widely. In general, there was less spike activity when the frequency of dysrhythmias was high. Thus, gastric myoelectric activity was disrupted from hours 48 to 168 after GDV with tube gastrostomy and after tube gastrostomy alone. Surgically induced GDV alone did not produce any significant or sustained dysrhythmias.     

ASSOCIATION BETWEEN MALIGNANCY AND SONOGRAPHIC HETEROGENEITY IN CANINE AND FELINE ABDOMINAL LYMPH NODES

Abdominal lymph node enlargement is frequently noted sonographically. Certain sonographic features can be used to suggest whether lymphadenopathy is more likely benign or malignant. Specific changes in size, shape, echogenicity, and Doppler flow patterns have an association with malignancy. In this retrospective case-control study, the association between abdominal lymph node heterogeneity and malignancy was evaluated. Twenty-three canine and 18 feline patients with ultrasonographically heterogeneous abdominal nodes were evaluated for presence of benign or malignant lymphadenopathy. Controls were animals with lymph node enlargement of uniform echogeneity. Twenty-one (91%) of heterogeneous canine lymph nodes were malignant, and there was a significant association between heterogeneity and malignancy in canine abdominal lymph nodes (P= 0.024). Seven (63%) heterogeneous feline lymph nodes were malignant, with no significant association between heterogeneity and malignancy (P = 0.537).