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Jan de Leeuw Margaret N. Waweru Onyango O. Okello Moses Maloba Paul Nguru Mohammed Y. Said Hesbon M. Aligula Ignas M. A. Heitk nig Robin S. Reid 《Biological conservation》2001,100(3):297-306
Arid rangelands host a variety of drought-tolerant wildlife species, many of them requiring conservation efforts for the survival of their populations. The development of drinking water sources for people and livestock forms one of the main development interventions in these rangelands. However, the impact of availability of permanent drinking water on wildlife remains unknown. In this study we analyzed the distribution of wildlife and livestock in northern Kenya in relation to distance to permanent water. Livestock were concentrated in areas close to permanent water, while wildlife were frequently farther away from water; their distributions were inversely correlated. In addition, wildlife assemblages were more diverse farther from water. These results suggest that livestock and human activities related to water points negatively affect the distribution of wildlife. 相似文献
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Neospora caninum infects bovine hosts giving rise to pro-inflammatory immune responses that can result in foetal death or spontaneous abortion, this appears to be mediated by the actions of IFN-γ on cell activation and migration/trafficking. Yet successful vaccination or natural immunity is also strongly correlated with IFN-γ production. We utilised in vitro infection of bovine macrophages to prime naive T-cell responses. Naive T-cells in contact with infected macrophages produce both IFN-γ and IL-17 in a pattern that is dependent on whether the priming macrophage was protected or non-protected. Our results may explain the apparent dual role of IFN-γ during infection if a second major pro-inflammatory cytokine, IL-17, is produced simultaneously. 相似文献
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Alban L Pozio E Boes J Boireau P Boué F Claes M Cook AJ Dorny P Enemark HL van der Giessen J Hunt KR Howell M Kirjusina M Nöckler K Rossi P Smith GC Snow L Taylor MA Theodoropoulos G Vallée I Viera-Pinto MM Zimmer IA 《Preventive veterinary medicine》2011,99(2-4):148-160
Each year, more than 167 million pigs in the European Union (EU) are tested for Trichinella spp. under the current meat hygiene regulations. This imposes large economic costs on countries, yet the vast majority of these pigs test negative and the public health risk in many countries is therefore considered very low. This work reviewed the current Trichinella status across the EU as well as the national level of monitoring and reporting. It also reviewed which animal species were affected by Trichinella and in which species it should be surveyed. This information was used to design a cost-effective surveillance programme that enables a standardised monitoring approach within the EU. The proposed surveillance programme relies on identifying sub-populations of animals with a distinct risk. Low-risk pigs are finisher pigs that originate from so-called controlled housing. All other pigs are considered high-risk pigs. Controlled housing is identified by the application of a specific list of management and husbandry practices. We suggest that member states (MS) be categorised into three classes based on the confidence that Trichinella can be considered absent, in the specified sub-population of pigs above a specified design prevalence which we set to 1 per million pigs. A simple and transparent method is proposed to estimate this confidence, based on the sensitivity of the surveillance system, taking into account the sensitivity of testing and the design prevalence. The probability of detecting a positive case, if present, must be high (>95 or >99%) to ensure that there is a low or negligible risk of transmission to humans through the food chain. In MS where the probability of a positive pig is demonstrated to be negligible, testing of fattening pigs from a sub-population consisting of pigs from controlled housing can be considered unnecessary. Furthermore, reduced testing of finishers from the sub-population consisting of pigs from non-controlled housing might even be considered, if conducted in conjunction with a proportionate sampling scheme and a risk-based wildlife surveillance programme where applicable. The proposed surveillance programme specifies the required number of samples to be taken and found negative, in a MS. A MS with no data or positive findings will initially be allocated to class 1, in which all pigs should be tested. When a MS is able to demonstrate a 95% or 99% confidence that Trichinella is absent, the MS will be allocated to class 2 or 3, in which the testing requirement is lower than in class 1. 相似文献
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