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Sources of casein protein and wheat gluten were analysed for the content of proteins, fats, saccharides, water and amino acids. The chemical score of the amino acids and the ratio of essential and non-essential amino acids (E/N) were determined. In rats (males) at the age of 120 days, given the diets for 14 days, the optimal and maintenance physiological daily rations were determined from the changes of body nitrogen, body water and weight dependent on the protein intake, using the method of increasing casein protein and wheat gluten content from 0 to 40 per cent in the diet. In 120-134-day-old rats, the optimal daily dose was 1.75 g of casein protein (7.5 per cent of all proteins in the diet) and 2.46 g of wheat gluten protein (10 per cent of all proteins in the diet). As to the maintenance rations determined from the weight changes, body nitrogen and body water in dependence on the protein intake, in these rats the successive daily rations were 1216 mg, 1214 mg and 1302 mg for the casein protein, and 1731 mg, 1760 mg and 1861 mg for the wheal gluten protein.  相似文献   
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Summary The possibility of using proline accumulation and fluorescence inhibition as predictive tests for drought tolerance in durum wheat has been investigated. The drought susceptibility of 25 genotypes was evaluated by comparing yields and yield components in irrigated and non irrigated conditions in the field. A drought susceptibility index (DSI) was calculated based on yields from irrigated and dry treatments and compared with the results obtained using the two physiological criteria. Proline accumulation and chlorophyll fluorescence inhibition were found to be significantly and negatively correlated with DSI of grain yield, biological yield, and thousand kernel weight, and tiller index. The use of both criteria for breeding durum wheat in Mediterranean dryland is discussed.  相似文献   
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Episyrphus balteatus De Geer (Diptera: Syrphidae) is one of the most efficient biocontrol agents against Dysaphis plantaginea Passerini (Hemiptera: Aphididae) in apple orchards due to its early arrival. However, releasing flying predators in open orchards may be risky. We thus evaluated the combined effects of biological (early release of syrphids) and physical (Alt'Carpo nets) methods for controlling aphids under orchard conditions assuming that syrphids released under the nets will be able to survive and reproduce. Five experimental treatments containing two rows of trees each were set up in a pesticide-free orchard containing two different apple cultivars. For each cultivar, E. Balteatus adults were released (25, 40 and 90 adults per row) into three treatments, which were covered with nets, and two treatments were maintained free as controls (with and without nets). The releases, mainly in treatment 90, had a small effect on the development of the aphid population compared to netted control trees, especially towards the end of the study period when some of the differences were significant. This study demonstrated that E. balteatus adults can be successfully released under nets since we did observe an accumulation in the offspring of released individuals, mainly in treatments 40 and 90.  相似文献   
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Exclusion nets aimed at controlling populations of the codling moth, Cydia pomonella are increasingly used in French apple orchards. The secondary effects of these so-called Alt’Carpo nets on other apple pests have not yet been thoroughly determined. This study was carried out to evaluate whether the presence of white nets (mesh size: 3 × 7.4 mm) affects the population dynamics of the rosy apple aphid (RAA), Dysaphis plantaginea and the abundance and composition of associated arthropod communities. We surveyed 50 infested shoots on a weekly basis throughout spring in 2008 and 2009 on apple trees with or without (control) nets in one insecticide-free orchard located in south-eastern France. At three dates in 2009, the RAA infestation rate was also computed by counting the total number of infested shoots per tree. The nets were installed at three different dates during the RAA lifecycle: September (September Netting Plot (SNP)), March (March Netting Plot (MNP)) and mid-April (April Netting Plot (ANP)). The abundance of RAA in the uncovered plot in 2008 was 1.75-fold higher than in the ANP. In 2009, this abundance was 1.39-fold higher than in the ANP and MNP, and slightly lower than in the SNP (1.07-fold). The nets (MNP and SNP) decreased the number of RAA colonies present in early spring. Interestingly, the nets reduced the duration of RAA infestation by 7–10 days. The highest reduction in RAA abundance and infestation rate was observed when nets were closed during the RAA development phase (ANP). The nets significantly reduced the abundance of ants on the marked shoots, especially in the ANP compared to the control. In addition, this study showed that nets have a significant negative influence on the abundance and richness of RAA-natural enemies. There was a significant decrease in the abundance of predators but no effect on the abundance of parasitoids. Syrphidae, Forficulidae and Coccinellidae were the most abundant natural enemy groups in the uncovered plot. Netting the plots led to a pronounced decrease in Coccinellidae abundance, a slight but significant decreased in Syrphids and had no effect on earwigs. Overall, Alt’Carpo exclusion nets had a direct negative impact on RAA population dynamics especially in the presence of at least one active natural enemy per marked shoot. These promising findings suggest that the combination of physical and biological control methods has potential for regulating RAA populations in organic orchards.  相似文献   
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Innate immunity and host defense peptides in veterinary medicine   总被引:1,自引:0,他引:1  
Recent years have witnessed a surge in interest directed at innate immune mechanisms. Proper conceptualization of the key elements of innate immunity, however, is still a work in progress, because most research in immunology traditionally has been focused on components of the acquired immune response. The question of why an animal stays healthy in a world filled with many dangers is perhaps as interesting as why it sometimes surrenders to disease. Consequently, studies with an increased focus on inborn mechanisms of animal host defense may help further the development of appropriate preventative and therapeutic measures in veterinary medicine. Host defense peptides (HDPs) are central effector molecules of innate immunity, and are produced by virtually all living species throughout the plant and animal kingdoms. These gene-encoded peptides play a central role in multiple, clinically relevant disease processes. Imbalances in the expression of HDPs can lead to overt pathology in different organ systems and cell types in all species studied. In addition, HDPs are an ancient group of innate chemical protectors, which are now evaluated as model molecules for the development of novel natural antibiotics and immunoregulatory compounds. This review provides an overview of HDPs and is aimed at veterinary practitioners as well as basic researchers with an interest in comparative immunology involving small and large animal species.  相似文献   
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