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Providing phenotypic information, which is accurate, reliable, repeatable and comparable across countries or laboratories, is critical to gain a better understanding of the relationship between genes and phenotypes. So far, it is indeed extremely difficult to combine different sources of phenotypic data from multiple origins, partly because of the variability in the methods of phenotyping. The phenotyping program of livestock involves the definition of complex phenotypes obtained from data integration at different levels (from molecules to herds), the implementation of the latest technologies to accurately characterize at high speed and low cost, the greatest number of animals in a better characterized environment, and the development and sharing of large databases for data analysis and modeling. Such a program also involves the construction of a coordinated network of research and professional facilities and a common language with shared definition of unambiguous animal traits and of methods to assess them. To this end, it will build on the ‘Animal Trait Ontology of Livestock’ (ATOL) project with the objective of defining precisely the phenotypes of interest for farm animals. Then, it will be necessary to combine an environmental information system related to animal husbandry and associated methods to capture the phenotypic differences between animals.  相似文献   
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1. In three experiments the effect of diets containing maize or wheat on hepatic and plasma lipids in laying japanese quail were studied. In two of these diets of equal energy, nitrogen and fat contents were used. 2. Liver weight, relative to body weight, liver lipid content and plasma lipid concentration were greater in birds fed on maize-containing diets. 3. The maize-containing diet also produced more (14 : 0, 16 : 0, 16 : 1 and 18 : 1) and less (18 : 0, 18 : 2 and 20 :4) fatty acids in the liver lipid. 4. Egg production was not affected by the treatments. 5. The effect of dietary cereal on hepatic and plasma lipids may be due to altered lipogenesis and the quail may be a useful model for the laying hen with respect to hepatic lipid accumulation.  相似文献   
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This review examines some aspects of pig breeding schemes which affect their economic efficiency. These include the type of crossbreeding system, the selection applied within the lines, the importance of starting up relatively quickly, of maintaining efficient production within the breeding herds and of structuring the scheme so that improvements are passed down quickly to the commercial slaughter pigs.  相似文献   
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Apoptosis was studied in the lungs of pigs during an infection with a European strain of porcine reproductive and respiratory syndrome virus (PRRSV) and it was examined if cytokines were involved in the induction of apoptosis. Twenty-two 4- to 5-week-old gnotobiotic pigs were inoculated intranasally with 10(6.0) TCID50 of the Lelystad virus and euthanised between 1 and 52 days post inoculation (PI). The lungs and broncho-alveolar lavage (BAL) cells were assessed both for virus replication and apoptosis; BAL fluids were examined for interleukin (IL)-1, tumour necrosis factor-alpha and IL-10. Double-labellings were conducted to determine the relation between virus replication and apoptosis and to identify the apoptotic cells. Apoptosis occurred in both infected and non-infected cells. The percentages of infected cells, which were apoptotic, ranged between 9 and 39% in the lungs and between 13 and 30% in the BAL cells. The majority of apoptotic cells were non-infected. Non-infected apoptotic cells in the lungs were predominantly monocytes/macrophages, whereas those in the broncho-alveolar spaces were predominantly lymphocytes. The peak of apoptosis in the lungs at 14 days PI was preceded by a peak of IL-1 and IL-10 production at 9 days PI, suggesting a possible role of these cytokines in the induction of apoptosis in non-infected interstitial monocytes/macrophages. However, the latter hypothesis was not confirmed in vitro, since blood monocytes or alveolar macrophages did not undergo apoptosis after treatment with recombinant porcine IL-1 or IL-10.  相似文献   
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ABSTRACT The asexual phase of the life cycle of Plasmopara halstedii, the causal agent of downy mildew of sunflower, plays a key role in the propagation of the disease. We investigated the morphological and ultrastructural changes that occur during the asexual development of the pathogen. Direct examination of infected cotyledons confirmed the presence of sporangiophores. In contact with water, important ultrastructural changes occurred, affecting the surface of zoosporangia, which became smoother, and their cytoplasm, which differentiated into flagellate zoospores. The subsequent encystment of zoospores was characterized by the synthesis of a cell wall and the loss of the flagella. In addition, two monoclonal antibodies (MAbs) specific for P. halstedii were used to analyze the immunochemical changes associated with these modifications. MAb 16A6, which bound to a 48-kDa glycoprotein, mainly labeled the surface of mobile or encysted zoospores and of mother cells of germ tubes. Conversely, MAb 2F9, which recognized highly glycosylated antigens, labeled the surface of zoosporangia and of flagellate zoospores, but not the encysted zoospores. These results provide new insights into the morphological and ultrastructural changes associated with the release and the encystment of zoospores which may be interesting targets for the development of new antimicrobial products.  相似文献   
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伞滑刃线虫属分种检索   总被引:8,自引:0,他引:8  
依据2004年以前发表的所有伞滑刃属新种原始报道的资料,分析了伞滑刃属73个相关种的所有形态学分类特征,编制了64个伞滑刃属有效种的分类检索表.  相似文献   
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