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In 2005, the final phase of terrestrial rabies eradication in Germany was put at risk by a severe setback due to re-introduction of the disease in Rhineland-Palatinate from neighbouring Hesse after seven years of absence. The rapid westward spread of the disease prompted veterinary authorities to react swiftly and apply a new yet unproven vaccination strategy to rapidly increase herd immunity in an almost unprotected fox population to stop the epidemic. The cornerstones of this emergency oral rabies vaccination strategy, i. e. vaccination intervals, identification of high risk spots, real time epidemiological assessment, capable to eliminate rabies within 13 months after incursion are described here. This strategy may be used as a template to tackle similar emergency situations in Europe in the future.  相似文献   
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 Field studies on microbial populations and their activity in soil and litter layers of different sites revealed statistically significant correlations with climatic factors, soil characteristics and the number of terrestrial isopods (Isopoda: Oniscidea). The number of captured Porcellio scaber was negatively correlated with the density of soil microbiota, but positively correlated with both respiration and cellulolytic activity of litter-colonizing microorganisms. By contrast, the number of Oniscus asellus was positively correlated with soil microbial density and respiration, and cellulolytic and respiratory activity of the litter. These interspecific differences were unexpected between species that frequently occur sympatrically, and, thus, probably have similar ecological requirements. Hence, the results suggested species-specific interactions of these species with soil and litter-colonizing microbiota. However, further field studies are required to prove this. Received: 16 December 1998  相似文献   
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Selection of oat genotypes combining earliness and short plant height could stimulate oat cultivation worldwide. However, the mechanisms involved with the genetic control of heading date and plant height traits are not fully understood to date. This study aimed to identify genomic regions controlling heading date and plant height in two hulled by naked oat populations and to compare these genomic regions with that of other grass species. Recombinant inbred lines of each population and their parents were genotyped by a 6 K BeadChip Illumina Infinium array and assessed for heading date and plant height in two sowing dates. The quantitative trait loci (QTL) affecting these traits were detected by simple interval mapping. The two oat populations showed different genetic mechanisms controlling heading date. A major QTL was identified in one of the populations, mapped into the ‘Mrg33’ consensus linkage group from the current oat map. Two other QTL were detected into the ‘Mrg02’ and ‘Mrg24’ groups, in the second population. On the other hand, both populations presented the same genomic region controlling plant height. Six SNP markers, mapping on the same linkage group within each population, were associated with the trait, regardless the sowing date, explaining more than 20% of the phenotypic variation. Five of these six markers were mapped into three different linkage groups on the oat consensus map. Genomic regions associated with heading date and plant height in oat seem to be conserved in Oryza sativa L. and Brachypodium distachyon. Our results provide valuable information for marker-assisted selection in oats, allowing selection for earliness and plant height on early segregating generations.  相似文献   
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Long-term observations of Trichoniscus pusillus revealed that chemical composition and microbial activity of the leaf litter serving as food influenced the reproductive success of females and the mortality rates of juveniles as well. Of the food sources investigated, only alder litter, exhibiting high microbial activity, allowed the maintenance of a stable population with frequently reproducing females. This study concludes that the food type is a significant factor for population parameters of this parthenogenetic isopod. Our results on T. pusillus, belonging to the taxon Synocheta, are compared with data on terrestrial isopod species of the taxon Crinocheta.  相似文献   
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Sixteen 10-12-year-old and eight 1-year-old dogs were studied over a two year period to determine comparative differences in physiological response to 4 diets varying in protein content and percentages of energy contributed by protein. The ability of old dogs to utilize nutrients as supplied by these foods was not significantly different from that of young adult dogs. Except for indices of mitogenic stimulation and serum urea nitrogen (SUN) other physiological parameters studied were not affected by the diet fed. Regardless of diet, old dogs had significantly higher serum levels of cholesterol, phosphorus and alkaline phosphatase and had lower indices of mitogenic stimulation than did young dogs.  相似文献   
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The primary objective of this study was to evaluate the accuracy of the bentiromide test in differentiating between dogs with exocrine pancreatic insufficiency (EPI) and those with primary intestinal disease (PID). A secondary objective was to correlate the results of the commonly used diagnostic techniques with the results of the bentiromide test. This test consists of the oral administration of a synthetic peptide that is cleaved only by chymotrypsin. A subsequent rise in the plasma concentration of p-aminobenzoic acid (PABA) indicates the degree of cleavage, providing an in vivo assessment of chymotrypsin activity. Fourteen dogs with EPI and five dogs with PID were categorized on the basis of clinical signs, laboratory evaluations, and histologic examination of intestinal biopsies. Six normal dogs served as controls. The bentiromide test clearly identified the dogs with EPI and distinguished them from the dogs with PID and the control dogs. The results of the bentiromide test correlated well with the results of the clinical and laboratory evaluations. On the basis of these observations and conclusions, recommendations for the pragmatic application of the bentiromide test are offered.  相似文献   
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Lesions in 32 calves that died or were euthanatized during the course of severe natural infection with bovine respiratory syncytial virus (BRSV) are described. All calves had been dyspneic for 1 to 2 days. At necropsy, lesions that could be related to dyspnea included congested and cyanotic mucosae and widespread petechiae. The lungs had various lesions in the cranioventral (CV) and caudodorsal (CD) portions. The CV portion of the lungs was consolidated, firm, and edematous. Histologically, the main characteristic was degenerative, necrotic bronchiolitis, with few syncytial cells. Signs of repair, such as epithelial hyperplasia, fibrosis, and bronchiolitis obliterans, often were observed. The CD portion of the lungs was markedly distended, owing to severe edema and emphysema. Bronchiolar lesions were lacking in the CD portion. In 14 calves, hyaline membranes were seen in the CV and CD portions. Results of immunofluorescence for BRSV were positive in 24 calves, but only in the CV portion of the lungs. The calves had variable concentrations of BRSV-specific IgG1 and IgM in serum, lung lavage fluid, or both. The BRSV-specific IgA, on the contrary, was seldom detected. Thus, 2 discrepancies existed. Although the clinical picture appeared to be acute, bronchiolar lesions and serotest results suggested infection of longer duration. Also, although virus and viral cytopathologic features were detected only in the CV portion of the lungs, the CD portion had extensive lesions that consisted of emphysema and edema.  相似文献   
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