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31.
The effects of canopy, soil physico-chemical and microbiological variables on Sclerotinia stem rot (SSR) on soybean were assessed in two soils (clay loam and sandy loam) using multiple regression and canonical redundancy analysis (RDA) and their partial form to control for the rotation (2 or 3-y-corn/soybean monoculture) and fertilization (mineral/urban compost) or spatial variables effects. The models revealed the minimal sets of variables that best explain the variance of the survival of Sclerotinia sclerotiorum’s sclerotia, carpogenic germination, disease severity and their associations. In clay loam, the 3-y-corn rotation reduced disease severity mainly through the reduction of weed biomass that favoured carpogenic germination. Urban compost has a conducive effect explained by a better soil surface drainage. Additionally, total N was found suppressive to sclerotial survival. In sandy loam, the carpogenic germination was negatively correlated with high C mineralization quotient and aggregate stability but correlated positively with Ca. Sclerotial survival was negatively correlated with pH and Ca, and positively correlated with biological fertility index. Aggregate stability, Ca and pH were associated with the urban compost. The regression and RDA analyses allowed to identify key variables that drived SSR development and explain their relationship with the cultural practices, soil health, as well as the spatial variation of disease variables.  相似文献   
32.
Landscape Ecology - Plant populations in agricultural landscapes are mostly fragmented and their functional connectivity often depends on seed and pollen dispersal by animals. However, little is...  相似文献   
33.
The growth response to supplementation of mixed diets with a protein extracted from frozen squid (squid protein fraction: SPF) was tested at levels of 1.5, 3.0, 6.0 and 16.0% in the diet in four species of shrimp: Penaeus stylirostris, P. vannamei, P. monodon and P. indicus. In P. stylirostris and P. vannamei , growth rates were significantly improved by SPF even at the lowest level of supplementation. Improvement was obtained only with 6 and 16 percent in P. monodon , while no significant response was observed in P. indicus. The growth promoting effect of SPF at 16% of the diet could be explained by its nutritional value, particularly by its amino acid content, although all diets were supposed to be well balanced in all known nutrients. However, at lower levels the results obtained seemed to be due to the unknown growth factor (UGF) already mentioned in previous reports.  相似文献   
34.
1. Guinea-fowl of both sexes and female chickens were fed from 1 to 12 weeks on diets the energy concentration of which was constant at either 2-6, 2-9 or 3-2 Mcal/kg (10-8, 12-1 or 13-4 MJ/kg) while the calorie to protein ratios were changed, for some groups, from 124 to 157 or 200 at 4 and 8 weeks. 2. Guinea-fowl, but not chickens, were unable to overconsume when the protein concentration was low with the result that the body fat content was not reduced when the protein concentration was increased. 3. In the second trial the ME level of the diets was fixed at 12-6 MJ/kg while the protein content was varied, from 21 to 28% in the diets fed to 6 weeks of age and from 15 to 24% in those fed from 6 to 12 weeks. 4. It is concluded that for the growing guinea-fowl the diet should contain 12-6 MJ ME/kg, the protein concentration reducing from 24 to 26% in the period 0 to 4 weeks to 19 to 20% in the period 4 to 8 weeks and to 16% or less in the period 8 to 12 weeks.  相似文献   
35.
Mid-infrared spectroscopy was applied to the analysis and discrimination of Cognacs and other distilled drinks (Armagnacs, whiskies, brandies, bourbons, rums, and counterfeit products). Strong correlations were found between dry extract spectra, polyphenolic dry extract spectra, and the total polyphenol concentration of samples, notably of Cognacs. Principal component analysis applied to spectral data made it possible to emphasize the importance of dry extract data when a distinction is made between Cognacs and Armagnacs, whiskies, bourbons, and rums, and of polyphenol concentration when Cognacs, brandies, and counterfeit products are separated. Ninety-six percent of samples in the test set were correctly assigned to Cognacs and non-Cognacs by partial least-squares discriminant analysis.  相似文献   
36.
Case history and presentationTwo non-human primates (Macaca fascicularis), weight 3.5 kg, enrolled in an experimental protocol received a 25 μg hour?1 transdermal fentanyl patch for postoperative analgesia. The following day both animals were clinically normal, but after a new induction of anaesthesia with ketamine, they developed severe and prolonged respiratory distress, profound coma and myosis.Management and follow-upAttempted reversal with naloxone was ineffective. After several hours of ventilation, both primates eventually died, 7 and 15 hours after ketamine injection, respectively. In both cases, the patch was discovered in the animal's cheek pouch. Subsequent fentanyl serum concentration measurements (8.29 and 14.80 μg L?1) confirmed fentanyl overdose.ConclusionsThis report of two fatal intoxications in non-human primates secondary to ingestion of a transdermal fentanyl patch demonstrates that this method of analgesia is inappropriate for non-human primates, because of their tendency to chew almost anything they can reach.  相似文献   
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In Cameroon, community forests are frequently presented as a relevant option to increase the welfare of rural populations and simultaneously improve local governance and forest resources conservation. But apart from community forests, rural livelihoods also depend on forest areas, designated as ‘domestic forests’ in this article, where local users enjoy informal customary rights. The specific contributions of community and domestic forests to the evolution of the prevailing socio-ecological system are assessed through a diachronic study of a village which is located in southern Cameroon. The Sustainable Livelihoods Framework is used to compare the progress of this social-ecological system between January 2008 and December 2009. The overall evolution of livelihoods was found to be positive during that period. In this case study, domestic forests and community forests are based on complementary models, which are often observed in southern Cameroon. Domestic forests constitute the basis of socio-economic development, while community forests might offer opportunities for a local-level carbon sequestration payment mechanism.  相似文献   
39.
正如今,由于基因科技和品种选育技术的不断提高,母猪品种无论是从环境适应度和营养需求都与过去的品种有非常大的差别。现代母猪的高繁殖力需要充足的营养来支持:从动物各种阶段的营养需求到各种阶段的饲喂方式及采食量,母猪的高繁殖潜力必须通过精确的营养来发挥。不同的营养方案根据不同的品种来制定;不同阶段的采食量根据其背膘和体重来决定。决定采食量的因素有:环境温度、霉菌毒素含量、饮水质量、饲料适口性等。  相似文献   
40.
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