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141.
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143.
Phenotypical and genotypical characterization of Shewanella putrefaciens strains isolated from diseased freshwater fish
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Between 2007 and 2012, a variety of disease outbreaks most often characterized by skin disorders were observed among different species of freshwater fish in Poland. In most cases, the clinical signs included focally necrotized gills, necrotic skin lesions or ulcers. Internally, haemorrhages, oedematous kidney and abnormal spleen enlargement were generally noted. The disorders were accompanied by increased mortality. Most of the problems concerned cultured common carp Cyprinus carpio L. and rainbow trout Oncorhynchus mykiss (Walbaum). Fish have been examined from a number of these farms, and additionally, the wild and ornamental fish with similar clinical signs of diseases were also tested. Bacteria were isolated consistently from lesions and internal organs. They had characteristic orange-pigmented colonies which grew in pure culture or constituted 55–95% of total bacterial flora. One hundred and eighteen isolates were collected and biochemically identified as Shewanella putrefaciens group, and this was confirmed by sequencing. Challenge tests confirmed the pathogenicity of these bacteria. This is the first report characterizing and describing S. putrefaciens as a pathogen of different species of freshwater fish in Europe. 相似文献
144.
Delaney Kevin J Breza-Boruta Barbara Lemańczyk Grzegorz Bocianowski Jan Wrzesińska Danuta Kalka Ireneusz Piesik Dariusz 《植物病害和植物保护杂志》2015,122(3):125-132
Journal of Plant Diseases and Protection - Plants induce volatile organic compounds (VOCs) after pathogen infection and exposure to a neighbouring infected plant. In a greenhouse, we measured VOCs... 相似文献
145.
Sylwia Magdalena Okoń Maria Chrząstek Krzysztof Kowalczyk Aneta Koroluk 《European journal of plant pathology / European Foundation for Plant Pathology》2014,139(1):9-12
Powdery mildew caused by Blumeria graminis DC. f. sp. avenae Em. Marchal. is a deleterious foliar disease of common oat which occurs in many parts of the world. Resistance existing in oat cultivars is broken down by new races of this pathogen and because of this fact there is necessity to look for new and effective sources of resistance to powdery mildew in oat. To identify new potential resistance sources to powdery mildew, a total of 67 oat genotypes from five different species Avena sterilis, A. fatua, A. sativa, A. maroccana and A. murphyi and 20 powdery mildew isolates were investigated for disease reactions. Among tested oat accessions the highest level of resistance was associated with A. maroccana genotypes. Genotypes belonging to species of A. murphi and A. sterilis also showed a good level of resistance. Identified genotypes could be used in oat breeding programmes to improve levels of resistance to powdery mildew. 相似文献
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147.
Jamroz D Wertelecki T Lemme A Wiliczkiewicz A Orda J Skorupińska J 《Journal of animal physiology and animal nutrition》2009,93(4):381-390
The experiment was carried out with ducklings fed-control feed mixture (Met level 0.3%) and mixtures supplemented with dl-methionine at the dose of 0.03 (II); 0.07 (III) 0.12 (IV) and 0.18% (V). In 5 h post-hatch (12 birds) and on days 3, 4, 6 always 18 birds were taken out from each treatment and killed, then the yolk sac (YS) and intestine were removed. The weight and chemical composition of YS residues (in them also amino acids) were analysed. Moreover on days 1, 3, 4 and 6, the amino acid pattern of YS residual protein was elaborated as well as length and weight of intestine were recorded. Increased doses of supplemental Met improved body weight gain after 4 days of ducklings life. All determined parameters were not affected by treatment. Development of intestines, yolk sac weight and yolk sac composition (DM, fat, protein, amino acid composition) changed with age; however, without any clear effect from dietary methionine level. No differences between sex and analysed parameters were stated. 相似文献
148.
R. G. Cooper Kh. M. A. Mahrose J. O. Horbańczuk R. Villegas-Vizcaíno S. Kennou Sebei A. E. Faki Mohammed 《Tropical animal health and production》2009,41(8):1669-1678
The aim of the current report was to study the literature pertinent to wild populations of ostriches and their ecological
and behavioural adaptations in the wild. Selected areas included palaeontology; ostrich distribution; conservation status
and relationships with humans and habitat. There is an immediate and urgent need to conserve and protect the apparently rapidly
declining populations of wild ostriches with the committed involvement of governments and funding bodies. Wildlife management
is an important complement to the farming of livestock. Scientists need to understand the elements of ostrich behaviour in
the wild in order to make informed decisions on their management and contact with other animals. Information of the like should
be included in readily-accessible and annually updated wildlife manuals. We deemed that such information was an essential
part in the conservation of this dwindling ratite. 相似文献
149.
Barbel larvae were reared for 21 days at 21.0, 24.1, 27.2 or 30.0 °C and fed ad libitum live Artemia nauplii for 16 h a day. The final survival rates exceeded 99 %. The highest mean daily growth rates, amounting to 0.97 mm total length (TL) and 17.3 % body weight (BW), were found at 27.2 °C. The optimum temperature calculated for the growth of larvae was 26.9 °C for TL and 26.5 °C for BW. An increase in water temperature accelerated the development rate to a larger degree than the growth rate. Temperature significantly influenced the final fish body chemical composition. The lowest dry matter content (19.1 %) was found at 24.1 °C. The highest values of ash content were determined for 27.2 and 30.0 °C and were 11.3 and 11.0 % of dry matter, respectively. The fish body caloric value was the highest at 30.0 °C (30.0 J mg?1). The analysis of changes in the fish body chemical features against the effective day-degrees age scale did not reveal significant influence of temperature. Therefore, the effects of temperature on larval body composition seem to be related mainly to differences in barbel developmental progress at particular temperatures. 相似文献
150.
Wojciech Czajkowski Justyna Mamnicka Wies?awa Lota Joanna Lewartowska 《Fibers and Polymers》2012,13(7):948-953
A number of water-soluble colourless fibre-reactive UV-absorbers derivatives of symmetrical triazine were used as additives during commercial laundering process. UV-protection factor (UPF) of such treated cotton tricot samples was measured. Changes in protection properties of modified textiles after repeated standard laundering process were determined. Carried-out experiments gave evidence of covalent bond formation between applied absorbers and cellulose fibre during standard washing process at 40 °C or 60 °C. Textiles modified by this method have provided UV-protective properties for prolonged time. 相似文献