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Davide Viglietti Margherita Maggioni Enrico Bruno Ermanno Zanini Michele Freppaz 《林业研究》2013,24(4):633-642
The presence of a thick snowpack could interfere with forest stability, especially on steep slopes with potential damages for young and old stands. The study of snow gliding in forests is rather comple... 相似文献
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M. S. Zanini E. C. Moreira C. E. Salas M. T. P. Lopes A. S. Barouni E. Roxo M. A. Telles M. J. Zumarraga 《Zoonoses and public health》2005,52(3):129-133
The identification of 163 strains of Mycobacterium bovis by polymerase chain reaction (PCR) and microbiological tests was carried out on 252 tuberculous‐like lesions (TLLs) collected from slaughtered cattle in south‐east Brazil. This study compared the usefulness of three genotyping techniques, IS6110‐restriction fragment length polymorphism (RFLP), polymorphic guanine‐cytosine‐rich sequence (PGRS)‐RFLP and direct repeat (DR)‐spoligotyping, as applied to M. bovis isolates. Based on IS6110‐RFLP genotyping we selected a group of 23 isolates containing more than one IS6110 copy, along with 16 samples containing one IS6110 copy from different geographical areas, evenly distributed among dairy (eight) and beef cattle (eight). These selected isolates were analysed by PGRS‐RFLP and DR‐spoligotyping genotyping. Dairy cattle (17%) display a higher frequency of multiple IS6110 copies than beef cattle (10%). A comparison between the genotype data obtained fails to show a correlation between the main clusters found by the three techniques. However, the clustering of each genotyping procedure revealed that the majority of strains are closely related. The RFLP‐PGRS patterns showed a sizable group (20.5%) containing a 5.5 kb fragment and the predominant spoligotype is similar to that from the BCG vaccine strain. Unexpectedly, four strains (2.4%) showed drug resistance to 0.2 μg/ml isoniazid and 20 μg/ml ethionamide, but none of them was resistant to rifampicin or other antibiotics tested. 相似文献
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Some indigenous fruit trees, in the drylands of southern Africa are worthy of interest because of their adaptation to environmental conditions prohibitive for traditional crops. Their fruits or their derivatives are traditionally used as an additional income by rural population, but little information is available about the properties of the soils that support their growth, although this information is necessary if the trees are subjected to sustainable domestication. Several soil properties are, however, to be considered as a whole and discriminant analysis provides a helpful tool to individuate the best conditions for the tree growth. Thirty-five soil samples were taken in areas where the trees naturally grow and produce, and the analytical data of the surface layer were used to relate soil properties to tree species. Four groups of trees were well separated using two discriminant functions that takes into account both the fertility characteristics (pH, organic C, N, texture, and properties of the exchange complex) and the Fe contents and distribution among the oxide forms. The discriminant functions allow a very acceptable reclassification of the data (more than 80% of cases correctly reclassified) and the classification coefficients were used to build an empirical equation that may help to identify the most suitable tree to be introduced at a new site. 相似文献
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The effect of a lack of snow cover in winter was investigated in two soils, beneath larch and meadow, in NW Italy (Vallée d'Aoste Region). During the late 1980s and early 1990s and 2000s, this region experienced extreme climatic conditions including a low snow pack and lack of snow cover for extended periods with important effects on soil temperature and nutrient dynamics. In particular, the mountain belt in the Alps may be extremely sensitive to these phenomena, in relation to the rise in average snowline projected under a warmer global climate. The study area is located at an elevation of 1450 m asl in the Italian Alps (Mont Mars Natural Reserve). During the winter 2003/04, snow was continuously removed in a treatment plot while a reference plot was maintained undisturbed. Soil temperature was measured at 10 cm depth by data loggers (UTL‐1). Soil N transformations in the topsoil (10 cm depth) were determined by the buried‐bag technique. The removal of the snow cover caused a significant decrease in soil temperature, related to concurrent decreases in air temperature. The lowest soil temperatures recorded were –4.3°C and –4.5°C beneath larch and meadow, respectively, on January 31, 2004. Soil temperature in the undisturbed plots was maintained above the freezing point when the snow cover was present. The snow removal caused significant increases in net ammonification in both soils and net nitrification only under meadow, but did not affect microbial biomass N which decreased in both plots. Our results suggest that the lower temperature reached in the plot without snow favored the production of inorganic N by physical rather than microbial degradation of soil organic matter (SOM). Soil freezing could enhance soil‐aggregate disruption releasing physically protected SOM and fragmentation of OM itself. 相似文献
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Molecular typing of Mycobacterium bovis isolates from south-east Brazil by spoligotyping and RFLP 总被引:2,自引:0,他引:2
Zanini MS Moreira EC Salas CE Lopes MT Barouni AS Roxo E Telles MA Zumarraga MJ 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2005,52(3):129-133
The identification of 163 strains of Mycobacterium bovis by polymerase chain reaction (PCR) and microbiological tests was carried out on 252 tuberculous-like lesions (TLLs) collected from slaughtered cattle in south-east Brazil. This study compared the usefulness of three genotyping techniques, IS6110-restriction fragment length polymorphism (RFLP), polymorphic guanine-cytosine-rich sequence (PGRS)-RFLP and direct repeat (DR)-spoligotyping, as applied to M. bovis isolates. Based on IS6110-RFLP genotyping we selected a group of 23 isolates containing more than one IS6110 copy, along with 16 samples containing one IS6110 copy from different geographical areas, evenly distributed among dairy (eight) and beef cattle (eight). These selected isolates were analysed by PGRS-RFLP and DR-spoligotyping genotyping. Dairy cattle (17%) display a higher frequency of multiple IS6110 copies than beef cattle (10%). A comparison between the genotype data obtained fails to show a correlation between the main clusters found by the three techniques. However, the clustering of each genotyping procedure revealed that the majority of strains are closely related. The RFLP-PGRS patterns showed a sizable group (20.5%) containing a 5.5 kb fragment and the predominant spoligotype is similar to that from the BCG vaccine strain. Unexpectedly, four strains (2.4%) showed drug resistance to 0.2 microg/ml isoniazid and 20 microg/ml ethionamide, but none of them was resistant to rifampicin or other antibiotics tested. 相似文献
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Cavagión L Perez A Santillan G Zanini F Jensen O Saldía L Diaz M Cantoni G Herrero E Costa MT Volpe M Araya D Rubianes NA Aguado C Meglia G Guarnera E Larrieu E 《Veterinary parasitology》2005,128(1-2):73-81
In 2000 Guarnera et al. proposed using ELISA in canine faeces collected from the ground to detect dogs infected with Echinococcus granulosus, thus determining sheep farms with active transmission. The objective was to evaluate the prevalence of E. granulosus infection in sheep farms of the Patagonia. Sheep farms were randomly selected in the Provinces of Río Negro, Chubut, Neuquén, Santa Cruz and Tierra del Fuego (areas with control programs) and La Pampa (comparison area). From one to three samples of fecal matter were obtained for each sheep farm, which were processed by means of copro-ELISA test with confirmation of positive samples by copro-Western blot. A total of 1042 samples were obtained from 352 sheep farms, 26 (7.3%) proving positive. Of these 5 (6.3%) were from La Pampa, 9 (13.8%) from Neuquén, 4 (4.7%) from Río Negro, 2 (2.9%) from Chubut, 1 (5.9%) from Santa Cruz and 5 (13.9%) from Tierra del Fuego. The identification of parasitized dogs is an essential activity upon which rests the strategy of control and surveillance. Arecoline tests or coproantigen test with fecal matter obtained directly from the dog contribute information on individual prevalence, while the use of coproantigens detected in ground-collected samples transfers the dog unit of observation to units of greater epidemiological value. In the present experience, the technique employed seems promising for its application in systems of epidemiological surveillance of cystic echinococcosis and in drawing a baseline on which to measure the progress of control programs in the Argentine Patagonia in subsequent years. 相似文献
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Zanini F Gonzalo R Pérez H Aparici I Soto X Guerrero J Cerrone G Elissondo C 《Veterinary parasitology》2006,138(3-4):377-381
Cystic echinococcosis is the most prevalent zoonosis in Tierra del Fuego province, Argentina, with important economic, productive and public health consequences. The present work was performed to determine the ovine prevalence in Tierra del Fuego, Argentina, as well as to evaluate the quality of diagnostic systems in slaughterhouses. Moreover, genetic analyses to characterize the strain of Echinococcus granulosus involved in the region were done. The first actions to perform a diagnosis of the epidemiological situation of hydatidosis in Tierra del Fuego were done between 1976 and 1977. A canine prevalence of 80% and an ovine prevalence of 55% results were obtained. Since 1979 the control program of Hydatidosis of Tierra del Fuego was implemented. It was based on semiannual canine anthelmintic treatment with praziquantel at dose of 5mg/kg, and complemented with sanitary education and canine and ovine epidemiological surveillance. During May 1997-January 1999: 5,916 sheep coming from 20 farms of the programmatic area were evaluated. In the lamb category, hydatid cysts were not found. In the adults category, 62 infected animals were found (3.2%). The ovine prevalence was 1.1% and there was 100% of coincidence between diagnosis in the slaughterhouse, re-inspection in the laboratory and histopathological study. The marked decrease in the prevalence observed for sheep infection evidenced a destabilization of the biological cycle of the parasite. This could be explained by the application of a control program with uninterrupted systematic actions. Polymerase chain reaction-ribosomal ITS-1 DNA (rDNA) restriction fragment length polymorphism (PCR-RFLP) analysis and partial sequencing of the mitochondrial cytochrome c oxidase subunit 1 (CO1) gene were used to characterize E. granulosus isolates collected from different regions of Tierra del Fuego to determine which genotypes occurred in this region. The results revealed the presence of the G1 genotype (sheep-dog strain). This is the first time that a molecular analysis was performed for the E. granulosus isolates from Tierra del Fuego. 相似文献
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The present work was performed to study the intestinal helminths of the patagonian grey fox (Pseudalopex griseus) and to obtain information about its possible role in the sylvatic life cycle of Echinococcu granulosus in Tierra del Fuego, Patagonia Argentina. Eighty-one foxes were captured and subject to post-mortem analysis. Thirty-one foxes (38.3%) harboured helminths. A total of six helminth species were recovered. Only one adult of E. granulosus was found in the studied samples. The current study is the first report of the intestinal helminths of the patagonian grey fox in Tierra del Fuego, Argentina and showed that this specie is probably not an important reservoir host for E. granulosus. 相似文献