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A study of the progress of the Aujeszky's disease control programme in Italy using survival analysis
Martini M Drigo M Dalla Pozza M Ferrari G Martinello F Sona B 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2003,50(4):191-195
A 3-year study (1997-2000) was performed on 294 swine herds from Italy, where a National Programme of Control of Aujeszky's Disease (AD) based on compulsory vaccination has been operative since 1997. Aim of the study was to evaluate the progress of this control programme using a survival approach applied to gE-seropositive herds at the beginning of the programme. The cumulative proportion of herds still gE-seropositive at the end of the study was 0.57. No significant difference in the probability of becoming gE-seronegative during the study period was found between herds of different type (breeding versus farrow-to-finish) whereas significant differences were seen between herds from different areas. The Cox's proportional hazards regression, performed on data from 79 herds, showed that the only risk factor significantly associated with a higher probability of becoming gE-seronegative is again the geographical location. Other risk factors considered in the analysis were: type of enterprise, type of replacement of animals, herd size, pig and pig herds densities around the farm, distance from the nearest pig herd and year of beginning of the vaccination with a gE-deleted vaccine. 相似文献
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Gallina G. Lucatello L. Drigo I. Cocchi M. Scandurra S. Agnoletti F. Montesissa C. 《Veterinary research communications》2010,34(1):69-72
Tilmicosin (TIM, Pulmotil®) was administered to eight rabbits by oral gavage at a dose of 12.5 mg/kg body weight for 2, 5, and 7 days, and its plasma kinetics and intrapulmonary disposition were investigated. TIM concentrations in plasma samples collected after days 1 and 6 of treatment were measured by high-performance liquid chromatography with ultraviolet detection. The pharmacokinetic parameters, obtained by non-compartmental analysis of TIM plasma concentrations, did not show any significant variations between days 1 and 6. From the second day of treatment, TIM concentrations attained in lung tissue and pulmonary alveolar macrophages (PAM) exceeded those in plasma by 7- and 400-fold, respectively, and high levels were maintained in lung tissues during the entire treatment duration. After the first day of withdrawal, a fast decline in TIM levels in both plasma and lung tissue was observed, but in PAM, much higher concentrations were maintained after 3 days of TIM withdrawal. 相似文献
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Barbara Drigo George A. Kowalchuk Johannes A. van Veen 《Biology and Fertility of Soils》2008,44(5):667-679
General concern about climate change has led to growing interest in the responses of terrestrial ecosystems to elevated concentrations
of CO2 in the atmosphere. Experimentation during the last two to three decades using a large variety of approaches has provided
sufficient information to conclude that enrichment of atmospheric CO2 may have severe impact on terrestrial ecosystems. This impact is mainly due to the changes in the organic C dynamics as a
result of the effects of elevated CO2 on the primary source of organic C in soil, i.e., plant photosynthesis. As the majority of life in soil is heterotrophic
and dependent on the input of plant-derived organic C, the activity and functioning of soil organisms will greatly be influenced
by changes in the atmospheric CO2 concentration. In this review, we examine the current state of the art with respect to effects of elevated atmospheric CO2 on soil microbial communities, with a focus on microbial community structure. On the basis of the existing information, we
conclude that the main effects of elevated atmospheric CO2 on soil microbiota occur via plant metabolism and root secretion, especially in C3 plants, thereby directly affecting the
mycorrhizal, bacterial, and fungal communities in the close vicinity of the root. There is little or no direct effect on the
microbial community of the bulk soil. In particular, we have explored the impact of these changes on rhizosphere interactions
and ecosystem processes, including food web interactions. 相似文献