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771.
OBJECTIVE: To determine whether the direction of dominance as determined by agonistic interactions away from food was different from the direction of dominance as determined by access to a resource in cats. ANIMALS: 28 cats. PROCEDURE: Dyadic relationships and hierarchy formed from observation of agonistic interactions away from food were compared with those formed from interactions at the food bowl. A cat was scored as subordinate to another cat if it lost 3 of 3 interactions or lost > or = 75% of the interactions when > 3 interactions occurred. RESULTS: Cats were observed for 449.4 hours. Hierarchy rank determined by agonistic interactions away from food was significantly correlated with rank determined by interactions at the food bowl. In 27 of 31 dyads, the direction of dominance was the same for food bowl and agonistic relationships, which was significant. In post hoc analyses, when considering the relationship between 2 cats, the heavier cat most likely ranked higher in each hierarchy; however, age was not significantly correlated with either hierarchy. On the basis of dyadic information, the older cat in a dyad was more often dominant in agonistic interactions. Males had a higher mean dominance rank than females; however, sex had no effect on rank determined by interactions at the food bowl. CONCLUSIONS AND CLINICAL RELEVANCE: Factors influencing dominant-subordinate relationships are of interest for understanding and treating behavior problems such as aggression and resource control. The outcome of agonistic interactions away from food was related to, but not perfectly correlated with, the outcome of interactions at the food bowl, although winners of those agonistic interactions tended to have control of food.  相似文献   
772.
OBJECTIVE: To assess the frequency of heart murmurs in overtly healthy cats. DESIGN: Prospective study. SAMPLE POPULATION: 103 healthy domestic cats. PROCEDURE: Background information and physical characteristics were assessed in cats that were candidates for blood donation during an 8-month period. For cats with heart murmurs, additional information collected included murmur timing, grade, point of maximal intensity, and presence of additional heart sounds. RESULTS: Heart murmurs were detected in 22 of the 103 (21%) cats. Echocardiography was performed in 7 of those 22 cats. The echocardiogram was considered normal in 1 cat; in the other 6 cats, diagnoses included hypertrophic cardiomyopathy (interventricular septal hypertrophic form [IVSH]; n = 4), left ventricular concentric hypertrophy with valvular disease (1), and equivocal IVSH (1). Thirteen cats had more than 1 examination during the study; 3 of them developed heart murmurs. There were no significant differences in age, sex, breed, coat color, eye color, or heart rate between cats with and without murmurs. Among the 103 cats, there were 6 pairs of siblings from 6 multiple-cat households and 16 cats from 7 multiple-cat households in which the cats were not related; the proportion of cats with murmurs was higher in the related cats (5/12) than in the unrelated cats (3/16), but the difference was not significant. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that heart murmurs are detectable in a large proportion of overtly healthy cats and that many murmurs appear to be caused by structural heart disease that is in a clinically latent state.  相似文献   
773.
OBJECTIVE: To assess cystoscopic transurethral resection (TUR) for the palliative management of dogs with neoplastic infiltration of the urethra. STUDY DESIGN: Prospective clinical trial. ANIMALS: Six client-owned dogs. METHODS: Cystoscopic examination and electrosurgical TUR were performed in dogs with urination difficulties caused by prostatic or urethral neoplasia. TUR was performed in a retrograde manner in female dogs and antegrade in male dogs via exploratory celiotomy and ventral cystotomy. Cystoscopic examination was used to determine the extent of neoplastic involvement of the urethra. TUR involved piecemeal removal of neoplastic tissue from the urethral lumen using an electrocautery cutting loop. Hemorrhage was controlled with a cystoscopic cauterized roller-ball. In 2 male dogs, intraoperative radiation therapy (IORT) was used to treat both prostatic neoplasia and the sublumbar lymph node bed. Surgical technique, complications, adjuvant treatment, and outcome were recorded. RESULTS: TUR was performed in 3 male dogs with prostatic carcinoma and 2 female dogs with urethral transitional cell carcinoma (TCC). In 1 female dog, TUR was attempted but not successful because of cystoscope diameter. Iatrogenic urethral perforation occurred during TUR in 3 dogs. In 2 dogs, prolonged exposure to lavage fluid resulted in clinical and biochemical abnormalities consistent with TUR syndrome. Dysuria resolved in 5 dogs within 10 days of TUR. Treatment-related complications included urinary tract infection and tumor seeding. Local tumor progression and metastasis occurred in all dogs. CONCLUSIONS: TUR (in combination with chemotherapy+/-IORT) resulted in rapid palliation of urination difficulties in male dogs with prostatic carcinoma. In female dogs with urethral TCC, however, electrosurgical TUR cannot be recommended because of a high intra- and postoperative complication rate with no improvement in postoperative management compared with historical reports of tube cystostomy. CLINICAL RELEVANCE: TUR is a novel alternative for the palliation of male dogs with prostatic carcinoma. In female dogs with urethral TCC, electrosurgical TUR does not provide any advantages compared with tube cystostomy.  相似文献   
774.
Between 1991 and mid 2000, the surveillance of Bovine Spongiform Encephalopathy (BSE) in France was based solely on clinical surveillance through a Mandatory Reporting System. Since 2000, the implementation of active surveillance programmes using rapid tests, as a complementary tool targeted at dead and slaughtered cattle has shown that part of the BSE cases were not detected with the clinical surveillance. In order to obtain a better knowledge of the strength of the clinical surveillance, we analysed a vigilance index defined as the ratio of negative clinical suspicions to the cattle population in the region and period of interest. The temporal analysis of the vigilance index showed that it did not vary much between 1991 and 1999, increased sharply since 2000, and then decreased partly in 2001. The geographical analysis of the variations of the vigilance index was performed at the department level by comparing the observed number of negative clinical suspicions per department to the expected number, computed on the basis of the national average index and standardised on the production type of the cattle - dairy versus beef suckling cattle. As assumed, the data followed a Poisson distribution. We observed a high geographical variation of the vigilance index: ten departments out of 91 presented a significantly higher vigilance index than the national one, and four a significantly lower vigilance index. The vigilance index showed that the clinical surveillance was heterogeneous during the past twelve years, both in time and geographic location, in a range of one to ten. So the apparent trend in the BSE epidemic during this period as well as the differences in the spatial incidence of BSE have to be analysed with caution.  相似文献   
775.
In the last 5 years, numerous molecular methods have been published for the detection and characterization of bacteria in the field of veterinary medicine. PCR has been the most commonly used technology. Although not currently used for clinical veterinary diagnosis, new technologies such as liquid-phase hybridization, real-time PCR, pathogen load determination and DNA/protein microarray have been described and have many possible applications in the clinical bacteriology laboratory because of their sensitivity and efficiency. This review describes the basic principles and application of recently published DNA-based molecular techniques for the purpose of veterinary clinical bacteriological diagnosis. It covers advances in probe hybridization technology, DNA/RNA amplification techniques and other molecular detection methods, including 16S rRNA analysis for bacterial characterization and DNA microarrays for bacterial detection. The review briefly summarizes the application of molecular methods for the diagnosis of specific important bacterial infections of animals, and for other animal pathogens that are slow or difficult to isolate in the clinical bacteriology laboratory. In addition, the molecular detection of antimicrobial resistance genes and of bovine mastitis pathogens is briefly described and current commercially available tests are listed.  相似文献   
776.
Data from the Food Safety Division, Alberta Agriculture, Food and Rural Development were analyzed to determine the frequency of diagnosis of porcine proliferative enteropathy (PPE) relative to the diagnosis of other porcine enteric infections between 1993 and 1997. Next to colibacillosis, PPE was the most commonly diagnosed enteric disease among those reported.  相似文献   
777.
The aim of the present study was to compare the amount of microbial N entering the duodenum and the efficiency of N utilisation for microbial protein synthesis in normal (NP, 17.4 g N/d) and low protein (LP, 7.5 g N/d) fed Corriedale sheep. Renal functional tests for urea handling studies, and determination of urinary allantoin as an indirect method to estimate the microbial protein production were used. Although the N intake was 57% lower in LP sheep, the microbial N production was not very different between both diets (NP: 3.99 +/- 0.01 vs. LP: 3.79 +/- 0.02 g/d, P < 0.05). The efficiency of the microbial protein synthesis in the rumen, expressed as grams of microbial N per kg of digestible organic matter apparently digested in the rumen, was not statistically different for both diets. The urinary elimination of urea was reduced by 84% in LP sheep, essentially due to an important decrease in both renal plasma flow (-63%) and glomerular filtration rate (-71%). These haemodynamic changes would also reduce the filtered load and the urinary elimination of allantoin, thereby leading to an underestimation of the amount of microbial protein entering in the duodenum. Since the renal urea spared by the kidneys remains in the blood, it limits the drop ofthe available urea for ruminal recycling consecutive to a low nitrogen diet.  相似文献   
778.
779.
Infection of calves by rotavirus could lead to diarrhea or subclinical disease. Therein, kinetic of viral excretion from a group of asymptomatic calves, previously exposed to a virulent strain of rotavirus, is compared to that of a group the calves of which had diarrhea associated with rotavirus infection. As determined by an enzyme-linked immunosorbent assay (ELISA), duration of rotavirus shedding in feces and maximum yield of virus antigen were similar within the two groups of calves. Rotaviruses isolated from the two above groups of animals were antigenically related as shown by neutralization tests, and showed a similar RNA electrophoretic profile. In conclusion, it is likely that both asymptomatic and diarrheic calves infected by rotavirus are equally a major source of contamination to contact healthy calves.  相似文献   
780.
Distinct rotaviruses isolated from asymptomatic calves   总被引:2,自引:0,他引:2  
Rotaviruses were isolated following cell culture of the intestinal contents of four non-diarrheic calves. The four isolates were serially propagated in MDBK and BSC-1 cells in the presence of trypsin and produced rotavirus particles morphologically similar to those found associated with diarrhea. They were antigenically related to the Nebraska calf rotavirus (Norden strain) as investigated by immunofluorescence. Three isolates could be distinguished from the reference Nebraska rotavirus by their thermal stability and/or their differential responses to intestinal neutralizing antibodies. Two isolates produced on BSC-1 cells plaques significantly different in size from the reference strain, No significant genomic variations were detected among the isolates.  相似文献   
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