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Abstract

Five old shrub rose taxa were studied in field experiments in northern Finland during the years 1993–1999. The plant material was micro-propagated from woody plants selected for their ornamental value and hardiness for northern areas of Finland. The observations in the experiments were based on phenological monitoring and survey of plant success. The results revealed significant differences in the success of the different rose genotypes, and the most valuable genotypes were identified. Micropropagation was successfully used as a propagation method and these in vitro propagated roses grew naturally under harsh field conditions. The Rosa ‘Tornedal’ origins, R. ‘Poppius’ and R. ‘Sipi’ were ranked the most suitable cultivars for northern landscaping. Overall, all of the studied roses succeeded fairly well.  相似文献   
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Paratuberculosis was diagnosed in a goat herd that participated in a sanitation program against Mycobacterium avium subsp. paratuberculosis. The aim of this study was to characterise the development of gamma interferon (IFN-γ) and antibody responses as well as the occurrence of faecal shedding. Faecal culture appeared surprisingly sensitive as about 18% and 40% of the goats were positive at 9 and 15-17 months of age, respectively, and shedding was often seen prior to peripheral immune responses. Peripheral IFN-γ responses were not related to protection as clinical and high shedding goats often had high responses. An IFN-γ response usually preceded a humoral response. However, positive antibody titers could sometimes be seen simultaneously with, and even prior to, IFN-γ responses. In conclusion, faecal culture appeared as sensitive as IFN-γ testing. Furthermore, the antibody ELISA and the IFN-γ assay may perform equally well in an infected herd if surveillance is conducted annually.  相似文献   
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A total of 147 dogs and 85 cats was surveyed for faecal carriage of thermophilic Campylobacters. Isolates were obtained from 33 (22.4 %) of the dogs and from 10 (11.8 %) of the cats investigated. The isolation rates recorded for diarrhoeic and non-diarrhoeic dogs and cats were not significantly different. Likewise, Campylobacters were isolated with about equal frequencies from puppies and mature dogs as well as from bitches and male dogs. Nineteen canine and 7 feline strains were biotyped and serotyped. A large majority (88.5 %) of these 26 strains belonged to serotypes previously recovered from human G. coli and C. laridis constituted 7.7 % and 3.8 %, respectively. Three strains belonged to serotypes previously recovered from human patients in Norway.  相似文献   
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