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185.
T. 《Forstwissenschaftliches Centralblatt》1898,20(2):66-72
Ohne Zusammenfassung 相似文献
186.
Understanding insect movement and distribution is critical for developing an effective insect pest management protocol. Movement and distribution of adult Cryptolestes ferrugineus (Stephens) in response to nominal temperature differences of 5, 10, 15, and 20°C in 1- and 2-m horizontal columns filled with 12.5% moisture content wheat were studied in 24, 48, and 72 h of movement times. In the wheat columns without temperature differences, adults had a diffusion distribution pattern caused by their random movement. Adults showed bias movement to the warmer grain in wheat columns with temperature differences and preferred the warmer grain regardless of the magnitude of temperature differences in less than 24 h. Their distribution did not have significant differences among different movement times in 1- or 2-m columns. About 40% of adults moved to the warmer wheat located at 0.4 to 0.5 m in the 1 m column but did not move to the warmer wheat located at 0.9 to 1 m in the 2-m column. Therefore, length of grain column influenced detection of warmer grain by insects. Adults under different temperatures had a similar response as that under linear temperature gradients. 相似文献
187.
The relative resistance of wheat, rye and triticale to take-all caused by Gaeumannomyces graminis 总被引:5,自引:1,他引:5
In seven field experiments conducted over 6 years with a wide range of disease severities, triticale was intermediate in resistance to Gaeumannomyces graminis between wheat (susceptible) and rye (resistant). Use of triticale is suggested as an immediately available means of introducing take-all resistance into cereal cultivation.
Octoploid triticale was slightly more susceptible than hexaploid triticale. There was little evidence of consistent variation in resistance among wheat or rye cultivars but a few hexaploid triticale cultivars varied in resistance. The resistance of triticale was not reliably expressed in the glasshouse tests used, so selection for resistance to take-all in a breeding programme would need to be conducted in the field. Individual pairs of rye chromosomes added to wheat did not significantly reduce its susceptibility. The feasibility of transferring the resistance of rye to wheat is considered. 相似文献
Octoploid triticale was slightly more susceptible than hexaploid triticale. There was little evidence of consistent variation in resistance among wheat or rye cultivars but a few hexaploid triticale cultivars varied in resistance. The resistance of triticale was not reliably expressed in the glasshouse tests used, so selection for resistance to take-all in a breeding programme would need to be conducted in the field. Individual pairs of rye chromosomes added to wheat did not significantly reduce its susceptibility. The feasibility of transferring the resistance of rye to wheat is considered. 相似文献
188.
Cannas da Silva J Noordhuizen JP Vagneur M Bexiga R Gelfert CC Baumgartner W 《The Veterinary quarterly》2006,28(1):23-32
The nature of veterinary work in dairy health management in Europe has changed over the past years and will change even more dramatically in the near future. The consumers and the media show increasing concern about animal welfare, safety of products of animal origin and traceability of animal products. Farmers in Europe have to produce under strict, often expensive and laborious regulations, while still commercially competing with farmers outside the EU and not subject to the same rules. Veterinarians should adapt their knowledge and skills to the new challenges and developments of the dairy sector. Dairy farmers nowadays ask for support in areas that go beyond clinical activities: environmental protection, welfare, nutrition, grassland management, economics and business management. Bovine practitioners should be able to advise in many different areas and subjects--that is the challenge to our profession. Veterinary education with regards to cattle health management should start with individual animal clinical work, which constitutes the basis of herd health advisory programmes. The bovine practitioner should then look beyond that and regard the herd as the unit. Each diseased cow or group of cows should be detected early enough to avoid financial losses or such losses should be prevented altogether by detecting and managing risk factors contributing to disease occurrence. Herd health and production management programmes represent the first level to optimise dairy farm performance. Expansions to that should further be considered, comprising both animal health and welfare issues, as well as food safety and public health issues. The latter could be addressed by quality risk management programmes following the HACCP-principles. Cattle veterinarians should follow recent developments and invest in new skills and knowledge in order to maintain their usefulness to the modern dairy farmer. Finally we are convinced that the cattle practitioner should evolve into this direction, otherwise the veterinarian as we know him will miss the train in the next years. 相似文献
189.
T L Lightfoot 《Veterinary Clinics of North America: Exotic Animal Practice》1999,2(2):447-69, vii
Veterinarians in small animal practice are being presented with an ever-increasing number of exotic species. It has become critical that veterinarians expand their professional knowledge to include the basic procedures necessary for the proper diagnosis and therapy of these animals. Yet the husbandry, temperaments, physiology, and anatomy of many of these species make extrapolation from our well-developed techniques in dog and cat medicine inadequate. This article discusses some of the major species concerns and clinical findings of chinchillas, hedgehogs, prairie dogs, and sugar gliders presented to the veterinary practitioner. Practical techniques for evaluation of these animals with minimal stress (to the animal, the practitioner, and the client) and maximum efficiency are addressed. 相似文献
190.
Heath TJ 《Australian veterinary journal》2002,80(8):468-473
OBJECTIVE: To map out the career paths of veterinarians during their first 10 years after graduation, and to determine if this could have been predicted at entry to the veterinary course. DESIGN: Longitudinal study of students who started their course at The University of Queensland in 1985 and 1986, and who completed questionnaires in their first and fifth year as students, and in their second, sixth and eleventh year as veterinarians. METHODS: Data from 129 (96%) questionnaires completed during the eleventh year after graduation were coded numerically then analysed, together with data from previous questionnaires, with SAS System 7 for Windows 95. RESULTS: Ten years after they graduated, 80% were doing veterinary work, 60% were in private practice, 40% in small animal practice and 18% in mixed practice. The equivalent of 25% of the working time of all females was taken up by family duties. When part-time work was taken into account, veterinary work constituted the equivalent of 66% of the group working full-time. That 66% consisted of 52% on small animals, 7% on horses, 6% on cattle/sheep and 1% on pigs/poultry. Those who had grown up on farms with animals were twice as likely to be working with farm animals as were those from other backgrounds. Forecasts made on entry to the veterinary course were of no value in predicting who would remain in mixed practice. CONCLUSIONS: Fewer than one-fifth of graduates were in mixed practice after 10 years, but the number was higher for those who grew up on farms with animals. Forecasts that may be made at interview before entry to the course were of little value in predicting the likelihood of remaining in mixed veterinary practice. 相似文献