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Silage is a high‐moisture‐content forage that is used to feed livestock. Using silage as feed is economically feasible and suitable for cattle management. Secale cereale is considered as a high‐quality forage plant. After the heading stage the biomass of S. cereale increases by up to 30%; however, lignification in the cell wall causes low fermentation efficiency and coefficient digestibility, and it may also be contaminated by mycotoxin‐producing fungi and can impair the quality of the silage. Therefore, the aim of this study was to screen beneficial Lactobacillius spp. for S. cereale silage to reduce fungi contamination and to increase fibrinolytic ability in the silage. Up to 100 days fermentation period and total 180 lactic acid bacteria were isolated and only a single isolate, R4‐26, showed strong acidification ability and antifungal activities against mycotoxin‐producing fungus. According to quantitative RT‐PCR results, the mycotoxin‐producing fungal contamination was significantly reduced in the S. cereale silage containing the R4‐26 isolate. In enzymatic assays, only a single isolate, R48‐27 demonstrated cellulase, xylanase, chitinase and esterase activities. In conclusion, the beneficial Lactobacillius spp. strains have the ability to reduce mycotoxigenic fungi contamination and increase fibrinolytic activity to improve quality of the S. cereale silage.  相似文献   
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Ionophorous antibiotics have been popularly used in the treatment of avian coccidiosis. Tissue residue of these antibiotics may be found in poultry, we have sought safe alternative anticoccidial herbal materials for the control of avian coccidiosis. Efficacy of extracts from 15 different herbs, including Bupleurum chinese DC, Sophora flavescens Aiton, and Artemisia annua Linne was tested against Eimeria tenella. One-day-old broiler chicks were infected with a USDA reference book of E. tenella, and administered various herbal extracts.Survival rates, lesion scores, body weight gains, bloody diarrhea, and oocysts excretions were investigated at the first and the second week after infection. Bloody diarrhea in the S. flavescens and Sinomenium acutum treated groups was milder than that of the other infected groups. Survival rates in the groups treated with Ulmus macrocarpa (100%), Pulsatilla koreana, Torilis japonica, Artemisia asiatica and S. flavescens (90%) were higher than that of the infected control group (70%). Lesion scores in the groups treated with U. macrocarpa (1.40+/-1.14) or Pulsatilla koreana (1.60+/-1.82) were significantly lower than those of the infected control group (3.00+/-1.10). During the first week after infection, the weight gains in the groups treated with Quisqualis indica (232.9+/-43.5 g), S. flavescens (214.4+/-46.1 g) and S. acutum (211.3+/-29.4 g) were significantly higher than the infected control group (172.4+/-17.6 g).In conclusion, the data of the survival rates, bloody diarrhea symptoms, lesion scores, body weight gains and oocyst excretions indicate that the extract of S. flavescens was the most effective. P. koreana, S. acutum, U. macrocarpa and Q. indica were also effective. Further research on the above herbal materials will be carried out by the authors by chemical analysis of the extracts.  相似文献   
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在过去的20年里,亚洲林业经历了引人注目的转型,包括从计划经济到市场经济的转变,从天然林供给木材到人工林供给木材的转变,木材替代品与非木质林产品的增加,地方分权与当地群众的参与,生态时代的发展与生态系统管理。在促进亚洲可持续森林资源管理中,市场工具、社区参与和环境服务都得到了应用。亚洲林业的转型表现出多样化,其森林、社会与环境之间的联系是丰富多彩的。  相似文献   
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This study analyzed the expression of growth-related genes of olive flounder, Paralichthys olivaceus, fed a low-fish meal (FM) diet to investigate the replacement of the FM diet in the field. The expression of growth hormone (GH)/insulin-like growth factor (IGF) axis genes in the brain/pituitary/liver and plasma hormone concentrations were measured. A basal experimental diet was formulated using 63% FM and 12% soybean meal as the primary protein sources, and then two other diets were made by replacing 20% and 30% of the FM with soy protein concentrate, tankage meal, and poultry by-products meal. Each diet was fed to duplicate groups of juvenile flounder (150 ± 3.0 g) twice a day. After 20 weeks, the plasma growth-related hormone concentrations were similar between the control and FM20 groups. Moreover, GH/IGF axis gene mRNA expression in the brain/pituitary/liver was similar between the control and FM20 groups. Immunoblotting of muscle and liver showed the same pattern. This study showed the utility of replacing 20% of the FM diet and supports the possibility of field application.  相似文献   
89.
Three dimensional FEM simulation for spinning of non-circular fibers   总被引:1,自引:0,他引:1  
A finite element method is employed for a flow analysis of the melt spinning process of a non-circular fiber, a PET(polyethylene terephthalate) filament. The flow field is divided into two regions of die channel and spin-line. A two dimensional analysis is used for the flow within the die channel and a three dimensional analysis for the flow along the spin-line. The Newtonian fluid is assumed for the PET melt and material properties are considered to be constant except for the viscosity. Effects of gravitation, air drag force, and surface tension are neglected. Although the spin-line length is 4.5 m, only five millimeters from the spinneret are evaluated as the domain of the analysis. Isothermal and non-isothermal cases are studied for the flow within the die channel. The relationship between the mass flow rate and the pressure gradient is presented for the two cases. Three dimensional flow along the spin-line is obtained by assuming isothermal conditions. It is shown that changes in velocity and cross-sectional shape occur mostly in the region of 1mm from the die exit.  相似文献   
90.
The synthesis of poly(norbornene ester)s by using a (η 3-substituted allyl) palladium (N-heterocyclic carbene (NHC)) complex as catalyst was performed and the relationship between chemical structure and glass transition temperature or refractive index of poly(norbornene ester)s was investigated. Norbornene ester monomers were synthesized via esterification of 5-norbornene-2-methyl alcohol and aromatic carboxylic acids. The polymerization catalyst, (η 3-substituted allyl) palladium (NHC) complex, was synthesized according to a published procedure. 1H-NMR spectroscopy was performed to determine chemical structure of monomers and polymers. The molecular weight of the polymers was measured via gel permeation chromatography and the thermal properties were analyzed via thermogravimetric analysis and dynamic mechanical analysis. Refractive indices of polymer films were measured using a prism coupler. Polymers with the highest M n (between 100 kg/mol and 300 kg/mol) were synthesized when the ratio of monomer to catalyst was 2000:1. The glass transition temperature of synthesized polymers was about 100 °C lower than that of conventional norbornene polymers. Among the six polymers of different chemical structures, four polymers exhibited a refractive index of 1.6 or more at a wavelength in the visible light region.  相似文献   
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