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Protection of biodiversity and ecosystem functions requires a better understanding of spatial diversity. Here we studied diversity
patterns of true bugs and saproxylic beetles, sampled in 28 forest stands of southern Germany, using a hierarchical nested
design of five increasingly broader spatial levels: trap location, stratum, forest stand, forest site, and ecoregion. We predicted
that: (1) for large body-sized species (as a surrogate for highly mobile species) and host generalist species (low host specificity),
the proportion of β-diversity decreases from small to large spatial scales; and (2) the differences between trait-based functional
guilds in the proportion of β-diversity increase with increasing weighting of more-abundant species. Our results indicated
that the ecoregion level is the most important diversity scale for both taxa and among functional guilds sampled, followed
by the forest stand level. Specialized species were more strongly affected on the ecoregion level than generalist species.
Differences in the proportion of β-diversity between functional guilds increased with increasing weighting of abundant species.
The β-diversity patterns based on body size and host specificity were similar for true bugs, but partly contrasting for saproxylic
beetles. Our results suggest that (1) future conservation schemes should focus on establishing new conservation sites in new
ecoregions, rather than on enlarging existing protected areas; (2) host specificity might be a more meaningful trait than
body size to be considered in biodiversity studies; and (3) common conservation approaches restricted to only large, conspicuous,
but rare species might result in a mismatch of important biodiversity scales. 相似文献
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Scrapie is a natural transmissible spongiform encephalopathy (TSE) of sheep, infecting the animal via the gastrointestinal tract or the skin. This project tested the hypotheses that lymph-borne cells (especially dendritic cells) are crucial for the systemic dissemination of the infectious agent from the site of infection in the skin, that PrP genotype affects PrPSC association with dendritic cells and that PrPSC carriage by cells affects their expression of cytokines. Skin, of scrapie-susceptible VRQ/ARR and scrapie-resistant ARR/ARR PrP genotypes, was scarified with FITC-labelled PrPSC. Pseudoafferent lymphatic cannulation was then used to monitor the presence of FITC-PrPSC over time in different lymph cell populations and plasma in the draining afferent lymphatics. The major observation was that PrPSC did not associate significantly with any lymphocyte or dendritic cell population in the 5 days following PrPSC scarification. The only cells seen to associate with PrPSC were neutrophils. Furthermore, despite the quantity of PrPSC used for scarification being equivalent to a standard infectious dose (the VRQ/ARR sheep dying at approximately 260 days) the only PrP found in afferent lymph during the 0-5-day period was proteinase K sensitive (i.e. soluble PrPC). No differences were observed between the PrP genotypes. Analysis of the effects of PrPSC scarification of cellular cytokine mRNA expression (by a nuclease protection assay) showed raised levels of IL-1beta and IL-8 in the susceptible VRQ/ARR group and raised levels of IFNgamma in the resistant ARR/ARR animals. 相似文献
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Virginia M. Venturina Anton G. Gossner John Hopkins 《Veterinary research communications》2013,37(2):171-181
Teladorsagia circumcincta is one of the most economically important gastrointestinal nematode parasites of sheep in cool temperate regions, to which sheep show genetically-varying resistance to infection. This is a very common parasite and viable sheep production requires the extensive use of anthelmintic drugs. However, the emergence of drug-resistant parasites has stimulated the search for alternative control strategies to curb production losses. Lambs become infected soon after weaning and begin to control parasite burden within 8–10 weeks of continual infection. This control is an acquired characteristic mediated by the development of parasite-specific antibodies. This paper describes the immunology associated with resistance and susceptibility, focussing on differential T cell activation that regulates the production of specific effector mechanisms. It continues by summarizing the methods used to identify genes that could be exploited as molecular markers of selection for resistance. In particular it focusses on the link between understanding the molecular immunology of infection and the identification of candidate genes for selection. 相似文献
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Human–Dromedary Camel Interactions and the Risk of Acquiring Zoonotic Middle East Respiratory Syndrome Coronavirus Infection 
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下载免费PDF全文 C. Gossner N. Danielson A. Gervelmeyer F. Berthe B. Faye K. Kaasik Aaslav C. Adlhoch H. Zeller P. Penttinen D. Coulombier 《Zoonoses and public health》2016,63(1):1-9
Middle East respiratory syndrome coronavirus (MERS‐CoV) cases without documented contact with another human MERS‐CoV case make up 61% (517/853) of all reported cases. These primary cases are of particular interest for understanding the source(s) and route(s) of transmission and for designing long‐term disease control measures. Dromedary camels are the only animal species for which there is convincing evidence that it is a host species for MERS‐CoV and hence a potential source of human infections. However, only a small proportion of the primary cases have reported contact with camels. Other possible sources and vehicles of infection include food‐borne transmission through consumption of unpasteurized camel milk and raw meat, medicinal use of camel urine and zoonotic transmission from other species. There are critical knowledge gaps around this new disease which can only be closed through traditional field epidemiological investigations and studies designed to test hypothesis regarding sources of infection and risk factors for disease. Since the 1960s, there has been a radical change in dromedary camel farming practices in the Arabian Peninsula with an intensification of the production and a concentration of the production around cities. It is possible that the recent intensification of camel herding in the Arabian Peninsula has increased the virus' reproductive number and attack rate in camel herds while the ‘urbanization’ of camel herding increased the frequency of zoonotic ‘spillover’ infections from camels to humans. It is reasonable to assume, although difficult to measure, that the sensitivity of public health surveillance to detect previously unknown diseases is lower in East Africa than in Saudi Arabia and that sporadic human cases may have gone undetected there. 相似文献
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Neff Felix Blüthgen Nico Chisté Melanie N. Simons Nadja K. Steckel Juliane Weisser Wolfgang W. Westphal Catrin Pellissier Loïc Gossner Martin M. 《Landscape Ecology》2019,34(8):2001-2015
Landscape Ecology - Insect herbivores comprise the majority of macroinvertebrate communities of temperate grasslands and act as drivers for important ecosystem functions. Landscape- and local-level... 相似文献
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Scherreiks Pascal Gossner Martin M. Ambarl&#; Didem Ayasse Manfred Bl&#;thgen Nico Fischer Markus Klaus Valentin H. Kleinebecker Till Neff Felix Prati Daniel Seibold Sebastian Simons Nadja K. Weisser Wolfgang W. Wells Konstans Westphal Catrin Thiele Jan 《Landscape Ecology》2022,37(3):745-762
Landscape Ecology - Current diversity and species composition of ecological communities can often not exclusively be explained by present land use and landscape structure. Historical land use may... 相似文献