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11.
The brucellosis surveillance scheme in Great Britain includes the serological testing of approximately 1 million bovine samples per year. These are screened by iELISA, positives going forward for confirmatory testing by CFT and SAT. Samples positive by confirmatory testing prompt substantial field investigations and interventions, but the animals involved are usually uninfected. Described below are a series of modifications to the screening method, which have resulted in a 10-fold reduction in false positive results whilst maintaining sensitivity. The key modifications include the introduction of blocking agents, a change in serum test dilution and the introduction of a control that directly defines the positive/negative cut-off. These simple modifications have had a large impact in reducing the cost of the surveillance programme due to reductions in confirmatory test requirements and a knock on effect of reducing costly field intervention.  相似文献   
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There is increasing concern that the intensification of dairy production reduces the concentrations of nutritionally desirable compounds in milk. This study therefore compared important quality parameters (protein and fatty acid profiles; α-tocopherol and carotenoid concentrations) in milk from four dairy systems with contrasting production intensities (in terms of feeding regimens and milking systems). The concentrations of several nutritionally desirable compounds (β-lactoglobulin, omega-3 fatty acids, omega-3/omega-6 ratio, conjugated linoleic acid c9t11, and/or carotenoids) decreased with increasing feeding intensity (organic outdoor ≥ conventional outdoor ≥ conventional indoors). Milking system intensification (use of robotic milking parlors) had a more limited effect on milk composition, but increased mastitis incidence. Multivariate analyses indicated that differences in milk quality were mainly linked to contrasting feeding regimens and that milking system and breed choice also contributed to differences in milk composition between production systems.  相似文献   
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In this study the correlation between positive contrast arthrography and arthroscopy was evaluated in a series of 20 shoulder joints (12 dogs) with radiographic and clinical evidence of osteochondrosis. The joints were consecutively examined by arthrography and arthroscopy. In 12 joints arthrography revealed the presence of a cartilage flap, and this finding was confirmed by arthroscopy. In 3 out of 8 joints where arthrography failed to demonstrate rupture of the cartilage, arthroscopy revealed the presence of a distinct fissure line. In 2 joints arthroscopy demonstrated a lesion comparable with chondromalacia and in 3 only a dimple in the articular cartilage was found. In 2 joints arthroscopy revealed the presence of small joint mice not detected by arthrography. Kissing lesions on the surface of the glenoid cavity opposite to cartilage flaps could be demonstrated as well. Evaluation of synovial inflammation, judged by the aspect and pattern of the synovial villi, correlated well with histologic findings. These results indicate that arthroscopy is a complementary examination in painful joints where arthrography fails to demonstrate rupture of the articular cartilage. It could be the procedure of choice if diagnostic and surgical arthroscopy can be combined. However, arthrography remains the technique of choice to demonstrate joint mice within the bicipital tendon sheath.  相似文献   
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Recent technological advances mean that samples from animal experiments may be analysed more cheaply, more easily and with a much greater return of data than previously. Research groups are frequently faced with a choice of continuing to use established technology in which they may have made a significant investment of time and resources, and have significant amounts of reference data, or switching to new technology where reference data may be limited. Apart from cost, the choice needs to be based on a comparison between the increase in data available from future experiments by switching and the value of comparison with reference data from historical experiments analysed with earlier technology. One approach to this problem is to ensure that sufficient quantity and variety of samples are taken from each experiment and appropriately stored to allow re-establishment of a sufficiently large reference set and to avoid the need to repeat animal experiments. The establishment of ‘biobanks' of experimental material will require funding for infrastructure, consistent storage of metadata and, importantly,horizon-scanning to ensure that samples are taken appropriately for techniques which will become accessible in future. Such biobanks are a recognised resource in human medicine, where the value of samples increases as more analysis is carried out and added to the metadata.  相似文献   
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Dairy farmers may be exposed to high levels of noise and dust. Protections against these hazards exist, but many farmers do not use them. An intervention consisting of hearing and respiratory screenings combined with personalized education was implemented. This study evaluates the impact of this intervention on farmers' self-reported use of personal protective equipment (PPE) and implementation of noise and dust abatement. Participants were screened as to noise (n=209) or dust (n=392) hazards and use of PPE. Following this, they were counseled on PPE use, and identification and reduction of noise or dust hazards. Counselors sought a pledge from the farmers to eliminate hazards and increase PPE use. Farmers were subsequently surveyed and asked whether they had implemented the changes. At baseline, 70% (146/209) of farmers exposed to high levels of noise reported poor use ("sometimes", "rarely", or "never") of hearing protection. Results indicated that two months after intervention, 25.2% (28/111) of these subjects had successfully improved their PPE use. At baseline, 79% (311/392) offarmers reported poor use of respiratory protection, with 27.3% (41/150) showing improvement in PPE use within the same time. Strategies to reduce noise hazards were identified by 92.8% (194/209) of hearing screening attendees; 13.2% (18/136) successfully reduced or removed exposure. These values for dust screening attendees were 98.2% (385/392) and 30.7% (54/176), respectively. Use of this intervention appears to be an effective method for increasing PPE use on the farm. However, it is not effective for reducing noise hazards.  相似文献   
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Samples of tissue from the central nervous system (cns), the lymphoreticular system (lrs) and the rectal mucosa of a large number of scrapie-exposed sheep, with and without signs of clinical disease, were examined immunohistochemically for evidence of disease-associated prion protein (PrP(d)). The rectal mucosa has received almost no attention so far in scrapie diagnosis, despite its abundant rectoanal mucosa-associated lymphoid tissue, and its accessibility. The scrapie-confirmed cases included 244 with clinical disease, of which 237 (97.1 per cent) were positive in the rectal mucosa, and 121 apparently healthy sheep, of which 104 (86 per cent) were positive in the rectal mucosa. PrP(d) was detected in 86.4 to 91.5 per cent of the other lrs tissues of the healthy sheep examined and in 77.7 per cent of their cns tissues. The stage of infection, therefore, affected the probability of a positive result in the rectal mucosa, whereas the breed, PrP genotype, age and sex had little or no independent effect. Accumulations of PrP(d) were observed in the rectal mucosa and other lrs tissues of vrq/arr sheep with preclinical and clinical scrapie, albeit with a lower frequency and magnitude than in sheep of other PrP genotypes. Western immunoblotting analyses of samples of rectal mucosa gave the characteristic PrP glycoprofile, with a sensitivity similar to that of immunohistochemistry.  相似文献   
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