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81.
Pfeiffer DU 《Veterinary microbiology》2006,112(2-4):259-264
Scientific evidence is one of the key factors to be considered in the development of disease control policies. It is generated using investigations into cause-effect relationships, which usually produce results that are associated with a varying degree of uncertainty. Experience has shown that taking account of these uncertainties can become a formidable challenge for policy makers when devising the strategies and when communicating them to stakeholders. The situation has been further complicated by a reduction in public trust in scientific evidence. It is now recognised that this challenge cannot be managed by simply providing more information, but it is also necessary to consider the influence that variation in risk perception amongst stakeholders has on their response to and commitment towards the policies. 相似文献
82.
The spatial distribution of sheep flocks in Great Britain with confirmed clinical scrapie between January 1993 and December 2002 inclusive was investigated by using kernel density estimation and a cluster scan test statistic. Six statistically significant clusters were identified: three were lower risk, and were centred on the north-western coast of Scotland, the north-western coast of Wales and the South Yorkshire/Pennine region; three were of higher risk, and were centred in the central south, North Yorkshire and north Cumbria. General knowledge and the results of previous epidemiological studies were used to generate biologically plausible hypotheses that might explain these findings. They included aspects of flock management and disease transmission, and factors associated with the identification of cases, including their detection, recognition and, in particular, reporting levels, as well as diagnosis and animal movements. 相似文献
83.
Micronutrient malnutrition affects over 2 billion people in the developing world. Iron (Fe) deficiency alone affects >47% of all preschool aged children globally, often leading to impaired physical growth, mental development, and learning capacity. Zinc (Zn) deficiency, like iron, is thought to affect billions of people, hampering growth and development, and destroying immune systems. In many micronutrient‐deficient regions, wheat is the dominant staple food making up >50% of the diet. Biofortification, or harnessing the powers of plant breeding to improve the nutritional quality of foods, is a new approach being used to improve the nutrient content of a variety of staple crops. Durum wheat in particular has been quite responsive to breeding for nutritional quality by making full use of the genetic diversity of Fe and Zn concentrations in wild and synthetic parents. Micronutrient concentration and genetic diversity has been well explored under the HarvestPlus biofortification research program, and very positive associations have been confirmed between grain concentrations of protein, Zn, and Fe. Yet some work remains to adequately explain genetic control and molecular mechanisms affecting the accumulation of Zn and Fe in grain. Further, evidence suggests that nitrogen (N) nutritional status of plants can have a positive impact on root uptake and the deposition of micronutrients in seed. Extensive research has been completed on the role of Zn fertilizers in increasing the Zn density of grain, suggesting that where fertilizers are available, making full use of Zn fertilizers can provide an immediate and effective option to increase grain Zn concentration, and productivity in particular, under soil conditions with severe Zn deficiency. 相似文献
84.
85.
The objective of this study was to assess the reproductive performance of Rwandan cattle and determine the effects of husbandry
practices on reproduction. One hundred and fifty Ankole and Crossbreed cattle from 87 farms, were body condition scored (BCS)
on a scale of 1(lean) to 5 (fat), and examined rectally for pregnancy and ovary size and structures present. Questionnaires
were completed by the farmers to obtain information on husbandry and management practices. The mean age of onset of puberty
was 27.7 ± 10.4 months, the interval from parturition to first oestrus was 8.7 ± 7.8 months, calving index was 16.8 ± 5.2 months
and 44% (95% CL 0.36-0.52) of cows examined rectally were anoestrus. Crossbred cattle reached puberty younger than Ankole
cattle, 23.4 ± 10.4 and 28.4 ± 9.6 months respectively (p < 0.05; t = 1.944; df = 121). Cows in poor BCS (< 2.5) are 1.67
times as likely to be in anoestrus as those with higher BCS (≥ 2.5) (χ2 = 9.476; df = 2; p < 0.01). Increased weaning age resulted in increased calving index (p < 0.001; t = −3.60; df = 38). Reproductive
performance of Rwandan cattle is poor. Many of the problems can be attributed to husbandry practices and lack of experience
and training in raising cattle. 相似文献
86.
87.
OBJECTIVE: To compare the profitability of three anthelmintic strategies in growing lambs in flocks with nematodes resistant to benzimidazole anthelmintics. METHOD: A partial-budgeting analysis was carried out by means of a stochastic simulation model, which allows inputs to be described as distributions rather than as fixed values, and hence permits variation between farms to be considered in the analysis. RESULTS: The results show that control of nematode parasites by use of an effective anthelmintic provides the highest net returns, yielding a margin over ineffectively treated lambs of A$114 per 100 lambs on average. Suppressive treatment based on the administration of two controlled-release capsules and monthly with moxidectin resulted in an average loss of A$131 per 100 lambs in comparison with animals treated with an ineffective anthelmintic. Analysis of the results from capsule-treated lambs did not take into account the unmeasured benefits associated with less contamination of pastures. Sensitivity analysis using a stochastic model indicates that apart from the effect of treatment on weight gain variation in carcase price greatly influences the profitability of all the parasite control programs examined. CONCLUSION: The results suggest that it is economically important for farmers to adjust their strategy in the presence of anthelmintic resistance. But as a result of uncertainty in the factors influencing economic return, the expected economic benefit is likely to vary substantially. 相似文献
88.
Pfeiffer E Guy N Cribb A 《The Canadian veterinary journal. La revue veterinaire canadienne》1999,40(4):265-267
A 10-year-old, female, spayed shorthair with presumed psychogenic alopecia was treated with clomipramine (1 mg/kg body weight/day). The cat developed urinary retention within 2 days. Clomipramine was discontinued. Clinical signs resolved over the next 7 days. The urinary retention was attributed to the anticholinergic effects of clomipramine. 相似文献
89.
The aims of this study were to estimate the wastage of horses registered for eventing in Britain, to investigate the reasons for this wastage and to evaluate factors affecting the horses' achievement of grade I status (at least 61 points) while registered. An analysis of the database of the British Eventing register found that 33.7 per cent of horses registered for the first time in 1999 were not re-registered for eventing in subsequent years. By using multivariable logistic regression analysis, it was shown that horses that were kept at an event yard were more likely to be re-registered than those kept on other premises (odds ratio [or] 2.0, 95 per cent confidence interval [ci] 1.2 to 3.2), and those that took part in showjumping while registered were also more likely to be re-registered (or 1.5, 95 per cent ci 1.1 to 2.2). Horses that took part in unaffiliated eventing while registered were less likely to be re-registered the following year (or 0.7, 95 per cent ci 0.5 to 0.9), as were those that were not insured (or 0.7, 95 per cent ci 0.5 to 1.0) and those from outside the British Isles (or 0.6, 95 per cent ci 0.3 to 1.0). Veterinary problems were the most commonly cited explanation (35.1 per cent) why horses that remained in their original ownership were not re-registered with British Eventing the following year. Horses from Australia were more likely to achieve grade I status than horses from the British Isles (or 9.7, 95 per cent ci 7.1 to 13.2), as were horses from New Zealand (or 6.4, 95 per cent ci 5.0 to 8.2), the usa (or 5.2, 95 per cent ci 3.8 to 7.2) and France (or 2.8, 95 per cent ci 2.1 to 3.7), but horses from the Netherlands (or 0.5, 95 per cent ci 0.3 to 0.9) and Belgium (or 0.3, 95 per cent ci 0.1 to 0.9) were less likely to achieve grade I status. Mares were less likely to achieve grade I status than geldings (or 0.4, 95 per cent ci 0.4 to 0.5). 相似文献
90.
An interactive electronic atlas has been developed with the purpose of providing a scaleable overview of spatial and temporal variation in animal production and health-related information for decision and policy makers in national and international institutions. The information contained in the atlas is currently managed and presented using the Key Indicators Mapping System (KIMS), and will also be integrated using the Key Indicators Database System (KIDS). Both systems were developed by the World Agricultural Information Centre of the FAO (FAO-WAICENT), the former as a stand-alone application and the latter for access via the Internet. Components of the atlas include vector maps, livestock disease and production databases, rules for country-level disease risk classification and 'disease cards' containing basic background information on diseases included in the atlas. The disease data is currently based primarily on Office International des Epizooties (OIE) disease reports, and the livestock production data on the FAO-WAICENT database. The atlas is highly interactive and allows visual presentation of information using maps, tables and charts. It also contains links to relevant resource information on the Internet. Diseases covered in the animal health layer include most OIE List A diseases and a subset of OIE List B diseases. Extensive analyses have been conducted to develop a set of qualitative and semi-quantitative criteria that allow improved disease status classifications based on 5-years cumulative OIE disease reports, and official disease control declarations. Classification rules were determined depending on the epidemiological features of each disease and considering spatial heterogeneity of disease presence in local regions. 相似文献