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991.
Rice culture of a toxigenic strain of Aspergillus ochraceus was fed at a concentration of 25% to weanling pigs for 10 days. The clinicopathological abnormalities reflected renal damage. Activities of lactic dehydrogenase, glutamic-oxaloacetic transaminase and isocitrate dehydrogenase were increased in the urine but not in the serum. Serum concentrations of urea nitrogen and creatinine were high. Cellular and granular casts, blood, protein, and glucose were in the urine of pigs fed toxic diet. Serum concentrations of K+, Na+ and Cl- were unchanged, but concentrations of these electrolytes were reduced in the urine.  相似文献   
992.
Intoxication of dogs with the mycotoxin penitrem A   总被引:1,自引:0,他引:1  
Mycotoxicosis caused by ingestion of moldy cream cheese was suspected in two dogs with severe muscle tremors and generalized seizures. Penicillium crustosum and its toxin, penitrem A, were isolated from the moldy cream cheese.  相似文献   
993.
Eighty-seven Bacteroides nodosus isolates were examined for elastase production by clearing of elastin particles in TAS agar medium. These included 54 ovine virulent isolates, 28 ovine benign isolates and five bovine isolates. In addition 22 ovine virulent, 16 ovine benign and two bovine isolates were examined for decline in proteolytic activity over a 13-day period in the degrading proteinase test using hide power-azure as substrate. There was a remarkable correlation between elastase production, relative stability of proteolytic activity in the hide powder-azure test and virulence of B nodosus. Ovine virulent isolates invariably produced elastase whereas ovine benign isolates and bovine isolates were elastase negative. Bovine isolates produced only mild lesions in the feet of challenged sheep.  相似文献   
994.
Acute viral hepatitis was diagnosed in five California sea lions (Zalophus californianus) stranded along the Los Angeles coast. Light microscopy revealed large nuclear inclusion bodies in hepatocytes. Electron microscopy provided evidence that these inclusion bodies were composed of adenovirus-like virions. Attempts to grow the virus in cell culture systems were unsuccessful.  相似文献   
995.
996.
997.
1. Agonistic interactions were observed over a 24‐week period in Rhode Island Red and in Nigerian local fowl aged 32 weeks or 12 weeks at the start of the experiments.

2. Agonistic interactions were both more numerous and more severe (fights and peck avoidances) in groups of the local breed than in those of Rhode Island Reds.

3. The outcome of severe interactions favoured local males and Rhode Island females in the first experiment and Rhode Island males in the second.

4. Small body and comb size might account for the relatively high number of agonistic interactions and the submissiveness of local females and young males while physical strength or some other breed characteristic might account for the high number of agonistic interactions of local males as well as their dominance in breed encounters.  相似文献   

998.
Objective The aim of this study was to perform a retrospective review of parotid duct transposition (PDT) in the dog to determine the rate and nature of complications, the success and failure rates and to evaluate owner satisfaction. Methods Medical records of 56 dogs (92 eyes) that underwent PDT and subsequent follow‐up by a veterinary ophthalmologist were reviewed. Forty owners (40 dogs/66 eyes) were contacted by telephone and 37 owners (37 dogs/60 eyes) also completed a visual analog scale questionnaire. Statistical evaluation included Wilcoxon Signed Rank tests, one‐way analysis of variance and Kaplan–Meier survival analysis with Wilcoxon and Log‐rank tests. Results The mean follow‐up was 38.7 months (range 1–109 months). The surgical success rate was 92% (85/92 eyes). Total failures (8%, 7/92 eyes) were because of severe saliva intolerance (n = 5 eyes) and PDT failure (n = 2 eyes). The complication rate was 50% (46/92 eyes) of which 61% (28/46 eyes) were managed medically and 39% (18/46 eyes) required further surgery. Ninety percent (36/40) of owners indicated that they would proceed with surgery again. Statistically significant improvements in owner perception of ocular comfort, number of daily topical treatments, ocular wetness, and postoperative vision were identified. Conclusions This study shows that PDT is a successful procedure based on clinical findings and in terms of owner perception. It has also demonstrated that PDT improves ocular comfort and vision in medically refractive cases of keratoconjunctivitis sicca, and that a low level of on‐going management is required in 33% of cases.  相似文献   
999.
We examined the design of a course that aims to ease the transition from pre-clinical learning into clinical work. This course is based on the premise that many of the difficulties with which students are confronted in this transition result from a lack of experience in applying knowledge in real practice situations. It is focused on the development of competence in solving clinical problems; uses an instructional model with alternating clinical practicals, demonstrations, and tutorials; and extends throughout the last pre-clinical year. We used a "proof-of-concept" approach to establish whether the core principles of the course design are feasible with regard to achieving the intended results. With the learning functions and processes as a frame of reference, retrospective analysis of the course's design features shows that this design matches the conditions from theories of the development of competence in solving clinical problems and instructional design. Three areas of uncertainty in the design are identified: the quality of the cases (information, openness), effective teaching (student and teacher roles), and adjustment to the development of competence (progress, coherence).  相似文献   
1000.
Commercial milking of sheep is a new agricultural industry in the United States starting approximately 30 yr ago. The industry is still small, but it is growing. The majority of the sheep milk is used in the production of specialty cheeses. The United States is the major importer of sheep milk cheeses with 50 to 60% of annual world exports coming to the United States during the past 20 yr. Therefore, there is considerable growth potential for the industry in the United States. The only dairy sheep research flock in North America is located at the Spooner Agricultural Research Station of the University of Wisconsin-Madison. The research program started in 1993 and has been multifaceted; dealing with several areas important to commercial dairy sheep farmers. The East Friesian and Lacaune dairy breeds were compared and introduced to the industry through the research program. Both dairy breeds produced significantly more milk than traditional meat-wool breeds found in the U.S., but the two breeds differed in their production traits. East Friesian-cross ewes produced more lambs and slightly more milk than Lacaune-cross ewes whereas Lacaune-cross ewes produced milk with a higher percentage of fat and protein than East Friesian-cross ewes. Lactation physiology studies have shown that ewes with active corpora lutea have increased milk yields, oxytocin release during milking is required to obtain normal fat percentages in the milk, large udder cisterns of dairy ewes can allow for increased milking intervals, and short daylengths during late pregnancy results in increased milk yield. In the nutrition area, legume-grass pastures and forages with a higher percentage of legume will result in increased milk production. Grazing ewes respond to additional supplementation with increased milk yield, but it is important to match the supplement to the quality of the grazing. Ewes on high quality legume-grass pastures that are high in rumen degradable protein respond with increased milk production to supplements high in energy and/or  相似文献   
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