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131.
The aim of this article was to study the conservation quality, chemical composition, gross energy, voluntary intake, and apparent digestibility of permanent meadow haylage and hay, fed to ponies at maintenance. The forages were from the same swath and harvested at early flowering stage. The apparent digestibility of the hay and haylage, which contained about 61% neutral detergent fiber and 38% acid detergent fiber, as fed, was determined by means of two in vivo digestibility trials, each performed on six ponies, weighing, on average, about 335 ± 80 kg and 334 ± 41 kg, respectively, over a 6-day feces collection period after a previous 14-day adaptation period. The voluntary intake was measured and the digestibility coefficients were calculated for dry matter, organic matter, gross energy, crude protein, neutral detergent fiber, and acid detergent fiber, using acid-insoluble ash as the internal marker. The haylages were evaluated for dry matter, pH, alcohols, lactic acid, and monocarboxylic acid. The conservation quality of the haylage was good and its chemical composition was similar to that of hay, except for the crude protein and gross energy contents, which were higher (P < .05) as compared with those of the hay. No differences were found between the hay and haylage with regard to the voluntary intake and digestibility coefficients.  相似文献   
132.
Climatic changes, together with an increase in the movement of dogs across Europe, have caused an increase in the geographical range of Dirofilaria infections. The present paper is focuses on northeastern European countries, where survey data have shown an increase of Dirofilaria repens infections both in animals and humans. A growing degree day-based forecast model has been developed to predict the occurrence. The model is based on evidence that there is a threshold of 14 °C below which Dirofilaria development will not proceed in mosquitoes, there is a requirement of 130 growing degree-days (GDDs) for larvae to reach infectivity, and there is a maximum life expectancy of 30 days for a mosquito vector. The output of this model predicted that the summer temperatures (with peaks in August) are sufficient to facilitate extrinsic incubation of Dirofilaria even at latitudes of 56 °N and longitudes of 39 °E. Despite the fact that both Dirofilaria immitis and D. repens have the same temperature requirement for extrinsic incubation in mosquitoes, empirical data has shown that D. repens is the main cause of dirofilarial infections in both humans and animals. Clinical signs are absent in most canine infections with D. repens. Furthermore, diagnosis is problematic and in-clinic serological tests, such as those for D. immitis, do not exist. Therefore, most infections go undiagnosed, allowing the infection to spread undetected.  相似文献   
133.
The evaluation criteria applied on a 34 set of minor and main olive varieties of a restricted and climatically disfavoured region of Italy have allowed to clearly identify some local varieties with valuable agro-ecological adaptation and outstanding oil quality traits. These traits are necessary for the establishment and/or improvement of olive culture in a disadvantaged cultivation area. The molecular and morphological analyses have allowed to establish the identity of local unknown ecotypes, establishing their relationships either with other local varieties or with wide-spread cultivars, while the evaluation of oil quality parameters ranked their suitability for further exploitation.  相似文献   
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135.
In the last two decades, the emergence and spread of antimicrobial-resistant pathogens, among them Salmonella, has become a serious health hazard worldwide, and specifically the high incidence of multidrug resistance has been encountered widely in many European countries. This study examines the antimicrobial supsceptibility of Salmonella enterica strains Typhimurium and Enteritidis isolated in Campania and Calabria region (Southern Italy) from animal and food of animal origin. The relationship of antibiotic resistance phenotype and the presence of some resistance genes has been also investigated. As espected, our results showes that resistance to ampicillin, chloramphenicol, streptomycin, sulphonamides and tetracycline is common, although resistance to other antibiotics (i.e.:nalidixic acid) and other resistance patterns occur. The genetic resistant patterns have been partially described for this food-borne pathogen but efforts are needed to realize the complete characterization of antimicrobial resistance genes.  相似文献   
136.
OBJECTIVE: To define the prevalence of overweight and obesity among school-aged children resident in mountain areas, rural areas and urban areas.Design, setting and subjectsThe sample (n = 12 832; 50.7% boys) included 9- and 11-year-old children of the Veneto Region of north-east Italy. Overweight and obesity status were determined using the International Obesity Task Force cut-off points for body mass index. The prevalence of overweight and obese subjects was calculated with a confidence interval of 95%. The Mantel-Haenszel method was used to compare the combined prevalence of overweight and obesity among children resident in mountain areas, rural areas and urban areas. RESULTS: Among boys the prevalence of overweight was 21.06%, while obesity prevalence was 5.92%; among girls overweight prevalence was 21.30%, while obesity prevalence was 5.15%. The prevalence was higher among 11-year-old boys (odds ratio (OR) = 1.19; 95% confidence interval (CI): 1.06-1.33) and 9-year-old girls (OR = 1.13; 95% CI: 1.01-1.26). Children resident in rural areas presented a higher risk of overweight and obesity compared with children resident in mountain areas (Mantel-Haenszel OR = 1.27; 95% CI: 1.13-1.42; chi2 = 17.55; P < 0.0001) and in urban areas (Mantel-Haenszel OR = 1.18; 95% CI: 1.07-1.31; chi2 = 10.39; P < 0.001). CONCLUSIONS: A relevant prevalence of overweight and obesity was found; the excess weight concerns one child in four. There are differences linked to different geographical areas that must be further investigated.  相似文献   
137.
  • ? Understanding tree mortality processes across time requires long term studies. Spatiotemporal patterns of mortality in a 200 years-old mono-layered Norway spruce stand were evaluated to determine what factors affected individual-tree mortality.
  • ? We performed an analysis on two surveys (1993 and 2005) in a 1-ha permanent plot in the Paneveggio forest (Eastern Italian Alps). Tree diameter and age distribution between surveys were compared. We examined spatial patterns of living and dead trees before 1993, in 1993 and in 2005 using univariate and bivariate Ripley’s K(d) function, and a kernel estimator of local crowding. A logistic model was used to assess the effects of diameter, age, recent growth and competitive pressure on tree mortality.
  • ? Spatial pattern analysis indicated mortality was associated to tree neighbourhood (neighbour effect at 2–5 m). An increment of regularization of tree spatial pattern occurred due to density-dependent mortality. Logistic regression showed tree diameter and recent growth were determinant on mortality risk during the monitoring period.
  • ? Even if the stand is relatively aged, mortality dynamics are those typical of stem exclusion stage. Mortality was related to competitive dynamics, and small suppressed trees with slow growth rate had higher probability to die.
  •   相似文献   
    138.
    139.
    Scaling is widely recognized as a central issue in ecology. The associated cross-scale interactions and process transmutations make scaling (i.e. a change in spatial or temporal grain and extent) an important issue in understanding ecosystem structure and functioning. Moreover, current concepts of ecosystem stewardship, such as sustainability and resilience, are inherently scale-dependent. The importance of scale and scaling in the context of forest management is likely to further increase in the future because of the growing relevance of ecosystem services beyond timber production. As a result, a consideration of processes both below (e.g. leaf-level carbon uptake in the context of climate change mitigation) and above (e.g. managing for biodiversity conservation at the landscape scale) the traditional focus on the stand level is required in forest ecosystem management. Furthermore, climate change will affect a variety of ecosystem processes across scales, ranging from photosynthesis (tree organs) to disturbance regimes (landscape scale). Assessing potential climate change impacts on ecosystem services thus requires a multi-scale perspective. However, scaling issues have received comparatively little attention in the forest management community to date. Our objectives here are thus first, to synthesize scaling issues relevant to forest management and second, to elucidate ways of dealing with complex scaling problems by highlighting examples of how they can be addressed with ecosystem models. We have focused on three current management issues of particular importance in European forestry: (1) climate change mitigation through carbon sequestration, (2) multi-functional stand management for biodiversity and non-timber goods and services and (3) improving the resilience to natural disturbances. We conclude that taking into account the full spatiotemporal heterogeneity and dynamics of forest ecosystems in management decision-making is likely to make management more robust to increasing environmental and societal pressures. Models can aid this process through explicitly accounting for system dynamics and changing conditions, operationally addressing the complexity of cross-scale interactions and emerging properties. Our synthesis indicates that increased attention to scaling issues can help forest managers to integrate traditional management objectives with emerging concerns for ecosystem services and therefore deserves more attention in forestry.  相似文献   
    140.
    Knowledge about the stand structure and dynamics of subalpine forests is crucial to preserve their multifunctionality. In the present study, we reconstructed the spatiotemporal dynamics of a subalpine Pinus cembra forest in the eastern Italian Alps in response to natural disturbances and forest management. We adopted a concurrent point pattern, dendroecological and growth dominance (GD) analysis. We mapped and measured all trees of Pinus cembra and Larix decidua in a 1?ha plot. We analyzed intra- and interspecific spatial patterns and spatial autocorrelation of tree size and age. We explored establishment dynamics and shifts in competition by analyzing growth suppression/release patterns and GD trends. Results showed a clumped, uneven-aged, multilayered structure where pine was dominant. The synergic action of ecological and human-induced factors is discussed to explain the prevalence of pine over time. Spatial pattern and autocorrelation analyses suggest a different colonization strategy of the two species, in which pine established after small-scale perturbations and experienced a stronger inter- and intra-specific competition. The interruption of tree establishment and shift in GD toward large trees resulting from the lack of forest management are the most important findings of this research. This highlights the importance of an active management to avoid the homogenization of the forest structure that is generally associated with a reduction in biodiversity and protective ability of forests.  相似文献   
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