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801.
The United Kingdom’s approach to encouraging environmentally positive behaviour has been three-pronged, through voluntarism, incentives and regulation, and the balance between the approaches has fluctuated over time. Whilst financial incentives and regulatory approaches have been effective in achieving some environmental management behavioural change amongst farmers, ultimately these can be viewed as transient drivers without long-term sustainability. Increasingly, there is interest in ‘nudging’ managers towards voluntary environmentally friendly actions. This approach requires a good understanding of farmers’ willingness and ability to take up environmental activities and the influences on farmer behavioural change. The paper aims to provide insights from 60 qualitative farmer interviews undertaken for a research project into farmers’ willingness and ability to undertake environmental management, particularly focusing on social psychological insights. Furthermore, it explores farmers’ level of engagement with advice and support networks that foster a genuine interest, responsibility and a sense of personal and social norm to sustain high quality environmental outcomes. Two conceptual frameworks are presented for usefully exploring the complex set of inter-relationships that can influence farmers’ willingness to undertake environmental management practices. The research findings show how an in-depth understanding of farmer’s willingness and ability to adopt environmental management practices and their existing level of engagement with advice and support are necessary to develop appropriate engagement approaches to achieve sustained and durable environmental management.  相似文献   
802.
ABSTRACT

To better understand the complexity of agricultural research, two Purdue University Libraries’ faculty members conducted a series of interviews with subjects from across the College of Agriculture. Interview questions addressed research methodologies and outputs, research data management, primary information resources, and other aspects of the research cycle and the researchers’ professional lives. Interviews were recorded, transcribed, and analyzed using nVivo software. The results are summarized and presented here.  相似文献   
803.
804.
Bovine babesiosis is caused by Babesia bovis and B. bigemina in Argentina. These protozoans are prevalent north of parallel 30 degrees S, where their natural vector Rhipicephalus (Boophilus) microplus is widespread. To prevent babesiosis outbreaks in endemic areas, an increasing population of 4-10-month-old calves are vaccinated with low virulence B. bovis R1A (BboR1A) and B. bigemina S1A (BbiS1A) strains. In non-endemic areas, an additional calf population is also vaccinated and boostered as adults, before they are relocated to R. microplus-endemic areas of the country. Serological tests are currently utilized not only to determine the status of natural Babesia spp. infections, but also to confirm the infection caused by vaccine strains. For this purpose, an indirect enzyme immunoassay (ELISA) based on the recombinant major surface antigen-2c (rMSA-2c) of B. bovis expressed in Escherichia coli, was standardized using sera from Babesia spp. experimentally infected cattle. ELISA(rMSA-2c) was validated using sera obtained weekly during 336 days from steers primed and boostered with BboR1A and/or BbiS1A on days 0 and 154, then compared with the immunofluorescent-antibody test (IFAT). Western blot (WB) protein analysis was used to confirm the specificity of the immune response to rMSA-2c. The sensitivity and specificity for ELISA(rMSA-2c) were 92 and 96% after the Babesia spp. priming and 88 and 73% after the boostering immunization, respectively. The sensitivity and specificity for IFAT were 99 and 90% after priming and 92 and 98% after boostering, respectively. Unlike IFAT, ELISA(rMSA-2c) detected a remarkable delayed booster response and a significant drop in specificity between 35 and 84 days after the booster immunization. Simultaneously, 87.5% of cattle boostered with B. bigemina showed cross-reactions in the ELISA(rMSA-2c), particularly between 63 and 77 days after the inoculation. A reaction against E. coli was observed, since bands of approximately 40 and/or 42kDa were detected using sera from cattle before and after Babesia spp. inoculations. ELISA(rMSA-2c) showed to be useful between 42 and 98 days after priming with Babesia spp. live vaccine to evaluate the success of infecting cattle. However, after boostering the test showed low specificity.  相似文献   
805.
Preputial scraping samples from 305 mixed breed beef bulls were examined for the detection of Tritrichomonas foetus infection. All samples were collected by veterinarians and transported in commercial media to an accredited lab. Upon arrival samples underwent microscopic examination for the presence of Tritrichomonas foetus and were then incubated until 5 days postcollection before final microscopic examination. Culture detected 14 samples with Trichomonad spp.; all were confirmed to be Tritrichomonas foetus by polymerase chain reaction (PCR). After final examination samples were randomly placed in groups of 5 samples; technicians were blinded as to culture results of the individual samples constituting each pool. From each sample within a group, a portion of the fluid sediment was removed and pooled with the other samples of the group to form 61 pools. From each of the formed pools an aliquot was removed for PCR. PCR detected 16 positive pools; an additional 2 positive samples were then identified on individual PCR on samples previously diagnosed as culture negative. Relative to culture, the 95% confidence intervals for sensitivity and specificity of PCR pools to detect Tritrichomonas foetus were 76.8% to 100% (mean value: 100%) and 85.5 to 99.5% (mean value: 93.4%), respectively.  相似文献   
806.
807.
Computed tomography (CT) is used to document upper airway lesions in dogs with brachycephalic obstructive airway syndrome. The presence of an endotracheal tube during CT scanning is often required for general anesthesia. We hypothesized that the endotracheal tube placement would change the soft tissue dimensions of the upper airway. The aims of this prospective, method comparison study were to evaluate the reliability of the previously reported upper airway CT measurements with endotracheal tube placement, and to propose measurements that are minimally affected by the endotracheal tube. Twenty brachycephalic dogs were included in this study. Each dog underwent head/neck CT with an endotracheal tube, followed by a second scan without the endotracheal tube. Ten measurements of the soft palate, nasopharynx, and trachea were performed. Tracheal dimension was significantly larger with the endotracheal tube compared to without, whereas the soft palate cross‐sectional area was significantly smaller with the endotracheal tube than without the endotracheal tube. The influence of the endotracheal tube on the caudal nasopharynx cross‐sectional (transverse‐sectional) area varied with a mean proportional absolute difference of 35%. Rostral soft palate thickness, tracheal perimeter, and cross‐sectional area of the rostral nasopharynx were the measurements least affected by the endotracheal tube (intraclass correlation coefficient = 0.964, 0.967, and 0.951, respectively). Therefore, we proposed that these three measurements may be most useful for future brachycephalic obstructive airway syndrome studies that require CT scanning of intubated animals. However, with endotracheal tube placement, measurements of soft palate length, caudal nasopharyngeal cross‐sectional area, and trachea height and width may not be reliable.  相似文献   
808.
809.
The influence of in vitro passage on Bartonella henselae pathogenesis in cats has not been thoroughly evaluated. Our objective was to examine the bacterial kinetics and humoral immune responses in cats experimentally infected with three different in vitro passages of B. henselae F1, a genotype I strain of feline origin. The F1 strain was in vitro passaged 20 and 40 times, and each was inoculated into a group of 5 cats. The kinetics of bacteremia and the feline humoral immune response to bacterial antigens were compared to a previous study involving a group of six cats inoculated with the original F1 strain. Among the three groups of cats, the kinetics of bacteremia profiles and the humoral immune responses to B. henselae lysates were similar. The influence of passage on bacterial membrane proteins was examined. In vitro passage altered the expression of 4/17 (23.5%) bacterial membrane proteins and 6/15 (40%) bacterial membrane antigens. An association between poor seroreactivity to three lysate antigens (15-, 18- and 45kDa), prolonged bacteremia and decreased serum bactericidal activity was noted. Our data show that in vitro passage of B. henselae did not alter the kinetics of bacteremia, including the occurrence of relapsing bacteremia, in experimentally infected cats. This suggests that highly passaged strains may not be suitable for future vaccination studies. Furthermore, in vitro passage results in phenotypic and antigenic changes in the bacterial membrane protein profile, which warrants caution in the interpretation of studies involving passaged B. henselae strains.  相似文献   
810.
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