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To better define the species-specific antioxidant systems and to ascertain the influence of the intracellular redox status on the immune system of different animal species, we determined lymphocyte glutathione peroxidase (GSHPx) activity, plasmatic glutathione levels (GSH) and the effect of H2O2 on the responsiveness of lymphocytes to proliferative stimuli. Among the three species considered, sheep presented the lowest plasmatic GSH and the highest lymphocyte GSHPx activity. On the contrary, dogs showed an inverted pattern (high GSH - low GSHPx). Horses displayed intermediate values for both parameters analysed. The effect of H2O2 on the proliferative capacity of lymphocytes was the same for all three species; the 200 microM dose in particular was strongly inhibiting. Each species, however, showed different rates of inhibition: sheep exhibited the highest sensitivity to the antiproliferative effect of H2O2. Our results confirmed that high H2O2 concentrations (200 microM) are noxious for the cellular functions of all animals; however this effect is mediated by a rigorously species-specific relationship between the intracellular reactive oxygen species (ROS) and the molecular systems involved in cell proliferation.  相似文献   
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Soil microbial activity is recognized as an important factor affecting nitrogen (N) release from slow-release fertilizers. However,studies on the effect of size and activity of soil microflora on fertilizer degradation have provided contrasting results. To date, no clear relationships exist between soil microbial activity and the release of N from slow-release fertilizers. Hence, the aim of this study was to better understand such relationships by determining the release of N from three slow-release fertilizers in soils with different microbial activities. Soils were amended with urea-formaldehyde (UF), isobutylidene diurea (IBDU), and crotonylidene diurea (CDU). Urea, a soluble fertilizer, was used as the control. Fertilized soil samples were placed in a leaching system, and the release of N was determined by measuring ammonium-N and nitrate-N concentrations in leachates during 90 d of incubation. Non-linear regression was used to fit N leaching rate to a first-order model. In all the treated soils, N was released in the order: urea (89%–100%) IBDU (59%–94%) UF (46%–73%) CDU (44%–56%). At the end of incubation, N released from CDU did not differ (P 0.05) among soils. On the contrary, UF and IBDU released significantly lower (P 0.05) amounts of N in the soil with higher microbial activity and lower pH.The rate constant (K_0) for UF was lower (P 0.05) in the soil with lower pH. Taken together, our results indicated that soil microbial size and microbial activity had a marginal effect on fertilizer mineralization.  相似文献   
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The relevance of precision agriculture produced a growth of the related literature over the years. However, a structured analysis of the published material is still missing. Thus, this study attempts to analyze the global scientific output of precision agriculture researches published during the period 2000–2016. By using a science mapping approach, mainly based on the application of network analysis tools, it was possible to investigate pivotal aspects of this research field such as publication trends, research topics and their geographical distribution. Using the Scopus database 17,756 scientific publications were retrieved from the chosen period. The number of publications increased after 2006, highlighting the vibrancy of the field. By authoring 35% of the publications, U.S.A. and China were the most active knowledge producer countries. Moreover, the generation of time resolved maps allowed us to identify agriculture engineering, computer science and agriculture studies as three main research areas characterizing precision agriculture panorama. The paper discusses the distribution of these topics at global level, among European countries and in Italy. Overall, this analysis represents the first holistic view of precision agriculture research providing valuable information for farmers, policy makers and researchers.  相似文献   
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A cross-sectional serological survey was conducted on cattle pasturing in an area of the southern Italian Apennines to evaluate the seroprevalence to Neospora caninum, and to investigate the climatic, environmental, farm management, and individual animal factors that influence the distribution of this protozoan. Blood samples were collected from 864 pastured cattle raised on 81 farms. Serum samples were tested for antibodies to N. caninum using an ELISA assay (HerdCheck), IDEXX). A geographical information system (GIS) for the study area was constructed using the following remote sensing (RS) and landscape feature data: autumn-winter, spring and summer normalized difference vegetation index (NDVI), land cover, elevation, slope, aspect, mean rainfall and minimum, mean, and maximum temperature in spring, summer, autumn and winter. Data on each of these features were then extracted for "buffer zones" consisting of the area included in a circle of 3 km diameter centered on the 81 geo-referenced centroids of the main cattle pastures. Climatic and environmental data obtained from RS and GIS and individual animal characteristics and farm management data obtained from a questionnaire were analyzed in relation to N. caninum seropositivity and antibody titres both by linear and logistic regression models. Out of the 81 farms sampled, 63 (77.8%) had at least one tested animal positive for N. caninum. Out of the 864 bovine sera samples, 266 (30.8%) were found to have antibodies to N. caninum. The results of the logistic regression model show that significantly high seroprevalence to N. caninum was found in heifers/steers and adults, in cattle raised on farms having a large number of dogs, and in cattle raised in buffer zones having high minimum temperatures in the spring, and a narrow extension of summer NDVI. In addition, positive linear correlations were found between N. caninum antibody titres and the number of dogs on farm, and the minimum temperature in spring. All the above determined risk factors for N. caninum seroprevalence indicate that horizontal infection resulting from the ingestion of oocysts shed by dogs is the most probable route of N. caninum infection in pastured cattle of the southern Italian Apennines.  相似文献   
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The fluorescence polarization assay (FPA) was evaluated for the serological diagnosis of brucellosis in water buffalo (Bubalus bubalis) in southern Italy. This assay uses O-polysaccharide prepared from Brucella abortus lipopolysaccharide conjugated with fluorescein isothiocyanate as a tracer. It has many methodological advantages over older, more established tests and can be performed in a fraction of the time. Sera from 890 buffalos from the Campania Region - 526 positive sera and 364 negative sera according to the complement fixation test (CFT) - were evaluated in this study. All samples were tested with the Rose Bengal test (RBT), CFT, and FPA in parallel and in blind fashion. Sensitivities (Sn) were 84.5% and 92.6%, and specificities (Sp) were 93.1% and 91.2% for RBT and FPA, respectively, relative to CFT. Finally, receiver operating characteristic (ROC) analysis suggested a cut-off value of 117 millipolarization (mP) units. On the whole, these results suggested that FPA might replace RBT in the diagnosis of buffalo brucellosis for its better performance relative to CFT, its adjustable cut-off useful in different epidemiological situations, its reliability, ease of performance, and for its potential application in field and high-throughput laboratories.  相似文献   
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In recent years, bats have been found to harbour many viruses, raising several questions about their role as reservoirs and potential disseminators of zoonotic viruses. We investigated the presence of six virus families in bats in three regions of Central‐Southern Italy. Astroviruses were identified in seven of 13 bat species. Sequence analysis revealed marked genetic heterogeneity among the astroviruses identified, with nucleotide identity ranging between 60.26% and 87.62%. Astrovirus diversity was not associated with the bat species, the geographic areas or the bat colony, suggesting the circulation of several astrovirus strains in Italian ecosystems. Genetic diversification and interspecies transmission appear common in bat astroviruses and could provide, potentially, the bases for transmission to humans and other mammals. Yet overemphasizing this risk might have detrimental consequences for bat conservation and preservation of the important ecosystem services bats provide.  相似文献   
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