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391.
J. Franz 《Journal of pest science》1941,17(4):37-41
Zusammenfassung Nach kurzer Darstellung der bekannten bionomischen Tatsachen wird die Abh?ngigkeit der Fra?menge von der Temperatur geprüft
und eine Steigerung bei zunehmender W?rme nachgewiesen. Die weite Verbreitung des Schildk?fers in den Minzefeldern der Moore
bei München h?ngt mit dem Vorkommen einer ursprünglichen Wirtspflanze (Mentha aquatica) zusammen. Eine gef?hrliche Massenvermehrung, die nach den Ern?hrungsverh?ltnissen zu erwarten w?re, wird durch starke Parasitierung
und besonders durch zwei- bis dreimalige Ernte mit gleichzeitiger Vernichtung der meisten Tiere vermieden.
z. Zt. im Felde
Mit 6 Abbildungen 相似文献
392.
393.
394.
395.
396.
Daniela Klein-J?bstl Tim Arnholdt Franz Sturmlechner Michael Iwersen Marc Drillich 《Acta veterinaria Scandinavica》2015,57(1)
Background
Calf disease may result in great economic losses. To implement prevention strategies it is important to gain information on management and to point out risk factors. The objective of this internet based survey was to describe calf management practices on registered dairy breeding farms in Austria and to estimate differences in calf disease incidences depending on farm structure and management practices.Results
A total of 1287 questionnaires were finally analysed (response rate 12.2 %). Herd characteristics and regional distribution of farms indicated that this survey gives a good overview on calf management practices on registered dairy farms in Austria. The median number of cows per farm was 20 (interquartile range 13–30). Significant differences regarding farm characteristics and calf management between small and large farms (≤20 vs >20 cows) were present. Only 2.8 % of farmers tested first colostrum quality by use of a hydrometer. Storing frozen colostrum was more prevalent on large farms (80.8 vs 64.2 %). On 85.1 % of the farms, whole milk, including waste milk, was fed to the calves. Milk replacer and waste milk were more often used on large farms. In accordance with similar studies from other countries, calf diarrhoea was indicated as the most prevalent disease. Multivariable logistic regression analysis revealed that herd size was associated with calf diarrhoea and calf respiratory tract disease, with higher risk of disease on large farms. Furthermore, feeding waste milk to the calves was associated with increasing calf diarrhoea incidence on farm. In the final model with calf respiratory tract disease as outcome, respondents from organic farms reported less often a respiratory tract disease incidence of over 10 % compared with conventional farms [odds ratio (OR) 0.40, 95 % confidence interval (CI) 0.21–0.75] and farmers that housed calves individually or in groups after birth significantly reported more often to have an incidence of respiratory tract disease >10 % compared with farms where all calves were housed individually (OR 2.28, 95 % CI 1.16–4.48).Conclusion
The results obtained in this study provide an overview on calf management on dairy breeding farms in Austria and may help to further point out areas to be improved on farm.Electronic supplementary material
The online version of this article (doi:10.1186/s13028-015-0134-y) contains supplementary material, which is available to authorized users. 相似文献397.
Cornelia Fürstenau Franz W. Badeck Petra Lasch Manfred J. Lexer Marcus Lindner Peter Mohr Felicitas Suckow 《European Journal of Forest Research》2007,126(2):225-239
In this study, the overall utility of forest management alternatives at the forest management unit level is evaluated with
regard to multi-purpose and multi-user settings by a multi-criteria analysis (MCA) method. The MCA is based on an additive
utility model. The relative importance of partial objectives of forest management (carbon sequestration, ground water recharge,
biodiversity, and timber production) is defined in cooperation with stakeholders. The forest growth model 4C (Forest Ecosystems
in a Changing Environment) is used to simulate the impact of six forest management strategies and climate on forest functions.
Two climate change scenarios represent uncertainties with regard to future climatic conditions. The study is based on actual
forest conditions in the Kleinsee management unit in east Germany, which is dominated by Scots pine (Pinus sylvestris L.) and oak (Quercus robur L. and Quercus petraea Liebl.) stands. First, there is an analysis of the impact of climate and forest management on forest functions. Climate change
increases carbon sequestration and income from timber production due to increased stand productivity. Secondly, the overall
utility of the management strategies is compared under the priority settings of different stakeholder groups. From an ecological
perspective, a conservation strategy would be preferable under all climate scenarios, but the business as usual management
would also fit the expectations under the current climate due to high biodiversity and carbon sequestration in the forest
ecosystem. In contrast, a forest manager in public-owned forests or a private forest owner would prefer a management strategy
with an intermediate thinning intensity and a high share of pine stands to enhance income from timber production while maintaining
the other forest functions. 相似文献
398.
H. J. Müller E. Hennig J. Syrjämäki V. Schefer-Immel B. Weber R. Mrkva M. Inouye G. F. Bornemissza F. J. Löcher M. Markkula S. Myllymäki K. Meunier H. Bruns M. Nuorteva S. Günther R. Lange J. Franz A. Szmidt W. Stein J. Franz A. Szmidt H. A. Koch E. Schwartz M. Schmidt 《Journal of pest science》1961,34(8):125-128
Ohne Zusammenfassung 相似文献
399.
400.
Friedrich Franz 《European Journal of Forest Research》1973,92(1):217-225
Ohne Zusammenfassung 相似文献