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Yuni Yupiana Peter R. Wilson Jenny F. Weston Emilie Valle Julie M. Collins‐Emerson Jackie Benschop Tim Scotland Cord Heuer 《Zoonoses and public health》2019,66(5):470-479
An epidemiological investigation was conducted in an unvaccinated dairy farming enterprise in which three workers on one of the milking herds (Herd 1) were diagnosed with leptospirosis due to serovars Hardjo (H) (n = 2) and Pomona (P) (n = 1) between January and March 2015. Blood and urine samples were collected from milking cows in Herd 1 (N = 230) and Herd 2 (N = 400), rising one‐ (R1, N = 125) and rising two‐year‐old (R2, N = 130) replacement heifers, and four pigs associated with Herd 1, in March 2015. Sera were tested using the MAT for serovars H, P, Copenhageni (C), Ballum (B) and Tarassovi (T), and urine samples were tested by qPCR. Seventy‐five per cent of 109 cows in Herd 1 and 36% of 121 in Herd 2 were seropositive (≥48), predominantly to H and P, and 23% of 74 cows in Herd 1 and 1% of 90 cows in Herd 2 were qPCR positive. Fifty‐five per cent of 42 R2 heifers were seropositive to T. No R1 and 17% of 42 R2 heifers were qPCR positive. Subsequently, all cattle were vaccinated for H and P, and Herds 1 and 2 were given amoxicillin. After the booster vaccination, 7% of 91 in Herd 1, 2% of 82 in Herd 2 and 11% of 38 R1 heifers (sampled as R2) were PCR positive. After the amoxicillin treatment, no cows in Herd 1 and 5% of 62 cows in Herd 2 were urine PCR positive. Calves and pigs were seropositive to H, P, C and B. Vaccination and antibiotic treatment appeared effective in reducing the risk of exposure of workers to vaccine serovars. However, evidence of non‐vaccine serovars indicated that workers likely remain at risk of exposure to Leptospira. 相似文献
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Detection and seroprevalence of morbillivirus and other paramyxoviruses in geriatric cats with and without evidence of azotemic chronic kidney disease
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Maximilian Wentzel Tim Koddenberg Holger Militz 《Wood material science & engineering》2020,15(4):223-228
ABSTRACT Eucalyptus nitens specimens were thermally modified under open and closed systems. The anatomical characteristics from selected modifications that presented similar mass losses were investigated by analyzing images taken from scanning electron microscopy, transmission light microscopy, and X-ray micro-computed tomography. Wood cell wall thickness, fiber, and lumen area were measured and compared to unmodified specimens, and the crack formation after modification was also analyzed. There was only a slight decrease in the measured characteristics when compared to unmodified specimens. The wood cell wall thickness was less affected than the fiber and lumen areas, and both modifications presented similar crack formations. Overall, there were no significant differences between open and closed system modifications in the anatomical structure. 相似文献
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The workloads, study methods, and motivation of students in a five-year BVSc program were studied using questionnaires and focus groups. Students in each year of the program were asked, on three occasions over an academic year, to record details of their out-of-class study time for each course they were taking and to record the study methods they used, how they prioritized their time between subjects, and how they allocated time to study and leisure activities. Mean response rates were 57% (range: 43-85%). Overall mean out-of-class study time ranged from 19 hours per week in Year 2 to 28 hours per week in Year 4. Study time was related to the level of interest the student had in the subject, the demands of assessments, and the number of subjects being studied. Study methods were related to students' perceptions of the requirements of the subject as well as to their interest in it. Reliance on memorization and the use of set study materials were the predominant methods for courses with low interest scores, whereas higher interest was associated with a broad range of study methods. Leisure time was ring-fenced, especially when workloads were high. Students' motivation was high when they were studying subjects that were new or were seen as relevant to clinical practice; when working with animals or with enthusiastic faculty members; and when involved in subjects more tightly focused on the ultimate goal of becoming a practitioner. It was poor when students were faced with high workloads, disciplines becoming "stale," excessive detail, and low perceptions of relevance. Constant assessment activities were also seen as a burden. In terms of good learning practices, workload and the demands of assessment were considered to be antagonistic. A tension between these perceptions of students and the values of faculty in terms of the development of critical thinking skills in the program is evident. 相似文献
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