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1.
This study was carried out to assess the effects of a blend of herbal essential oils (namely Thymus vulgaris, Mentha piperita, Rosmarinus offisinalis and Anethum graveolens) and different dietary lipid sources on the performance, ileal bacterial enumeration, intestinal histological alterations and immune responses in laying hens. For this purpose, a total of 150 laying hens were randomly allocated to six experimental treatments with five replicates of five birds each. Dietary treatments consisted of three levels of a mixture of essential oils (0, 100 and 200 mg/kg) and two sources of lipid (soybean oil and fish oil containing different ratios of n‐6 to n‐3 fatty acids) fed to the animals during an 80‐days feeding trial. Findings indicated that dietary administration of fish oil not only increased significantly the spleen relative weight (p < 0.01) and the antibody titre against Newcastle virus (p < 0.05) but also led to reductions in liver relative weight (p < 0.05) and feed conversion ratio (p < 0.05). Moreover, the mixture of herbal essential oils brought about declines in hepatic relative weight, heterophile to lymphocyte ratio (p < 0.05) and intestinal pathogen populations (p < 0.01). Mention must also be made of the improvements it made in spleen weight (p < 0.01), antibody titres against SRBC (p < 0.01) and Newcastle virus (p < 0.05), villus height to crypt depth ratio (p < 0.01), goblet cell numbers (p < 0.05), lamina propria lymphatic follicle diameters (p < 0.01) and feed conversion ratio (p = 0.06). It may be claimed that the enhancements observed in the performance of laying hens fed fish oil and 200 mg/kg of the blend of essential oils could have potentially been associated with improved intestinal health indices as well as cellular and humoral immune responses.  相似文献   
2.
A lysimeter experiment was conducted to investigate the effect of water table management (WTM) on distribution of soil salinity and annual alfalfa (Medicago scutellata) yield. Subirrigations with three levels of water table namely, 0.5 (WT0.5), 0.7 (WT0.7), and 1.0 m (WT1.0) and a free drainage (FD) conventional irrigation treatment were selected for this study. All treatments were arranged in a complete randomized block design with three replicates. The results of this study indicated that the average soil electrical conductivity of the saturated extract (ECe) in the root zone gradually increased and exceeded the designated crop threshold value (4 dS/m) after the first forage harvest in subirrigated lysimeters. A higher salt accumulation was observed at the WT0.5 treatment. The average dry matter yield of annual alfalfa in WT0.5 and WT0.7 treatments was found to be 52 and 73% higher compared with the control treatment, respectively.  相似文献   
3.
The antifungal activity of onion (Allium cepa L.) on two important dermatophytes, Trichophyton rubrum and Trichophyton mentagrophytes, with special reference to morphological aspects was studied. Growth of both fungi was found to be strongly inhibited by aqueous onion extract (AOE) as a dose-dependent manner. The extract showed fungicidal effect for both fungi at concentrations >3.12% (v/v). The fungus T. mentagrophytes was more affected by the onion as compared to T. rubrum at all concentrations used. Morphological effects of onion exposure were examined in correlation with fungal growth. Corresponding to the growth inhibition, light and electron microscopy observations revealed morphological anomalies in hyphal compartments. The results demonstrated that AOE targets the cell membrane of the fungi as breaking down of both inner and outer membranes with consequent extrution of materials into the surrounding medium. Cytoplasmic membranes and other membranous structures of organelles, such as nuclei and mitochondria, were also disrupted. In correlation to the fungal growth, morphological alterations occurred to a less content for T. rubrum compared with T. mentagrophytes. The hyphae of T. rubrum were found to be mainly affected by converting to resistant forms, i.e., chlamidospores as a consequence of phenotype switching response to AOE. Plasmolysis accompanied by an almost complete depletion and disorganization of cytoplasmic structures were found to be the final event which led to cell death. Ultrastructural evidences obtained from this study strongly support that morphological changes of T. rubrum and T. mentagrophytes caused by AOE are associated with its fungistatic and fungicidal activities. With respect to the morphological results and the preliminary data on fungal biochemistry, a mechanism of action by interacting of AOE with thiol (-SH) groups present in essential compartments of the fungal cells was postulated.  相似文献   
4.
Designing E1 deleted adenoviral vector by homologous recombination   总被引:2,自引:0,他引:2  
BACKGROUND: Adenoviruses are used extensively to deliver genes into mammalian cells, particularly where there is a requirement for high-level expression of transgene products in cultured cells, or for use as recombinant viral vaccines or in gene therapy. In spite of their usefulness, the construction of adenoviral vectors (AdV) is a cumbersome and lengthy process that is not readily amenable to the generation of large collection of clones. METHODS: In this project, to delete E1 gene in adenovirus, an adenoviral plasmid containing lateral sites of E1 region of adenovirus was made and recombination in the 293A cells between the homologous region of this linearized plasmid and the adenovirus genome resulted in the formation of the complete adenoviral recombinant. RESULTS: This recombination resulted in loss of E1 region and we constructed a recombinant adenovirus type 5 vector that E1 gene was deleted by homologous recombination. CONCLUSION: Homologous recombination is more easy and fast technique in the production of AdV.  相似文献   
5.
Genetic Resources and Crop Evolution - The genus Epilobium of Family Onagraceae is taxonomically a difficult group due to frequent inter-specific hybridization and species morphological overlaps....  相似文献   
6.
Genetic Resources and Crop Evolution - The genus Crocus of the family Iridaceae is a monophyletic genus with over 100 species. Due to the high degree of hybridization and the changes in the number...  相似文献   
7.
Genetic Resources and Crop Evolution - The pomegranate (Punica granatum L.) is an ancient fruit plant which has been consumed for its nutritional value and medicinal properties by mankind. Several...  相似文献   
8.
Genetic Resources and Crop Evolution - Melissa officinalis is an important medicinal plant and is extensively used by locals. This species is growing in different regions of Iran and forms several...  相似文献   
9.
Energy recovery from a crossflow ultrafiltration (UF) membraneunit employed in order to improve the performance of an anaerobic contact digester for the treatment of brewery wastewater was assessed. The performance of the pilot-scale anaerobic UF membrane system was studied for over 15 months. At steady-state conditions, an organic loading rate of 28.5 kg COD m-3 d-1, a hydraulic retention time of 4.2 days and overall COD and BOD removal efficiencies of 99% and almost 100% were achieved, respectively. Percent methane in biogas was found to be in a range of 67–79% with the corresponding methane yield of 0.28–0.35 m3 CH4 kg-1 CODremoved. The potential energy recovery from the system treating brewery wastewater at an OLR of 28.5 kg COD m-3 d-1 was 87 MJ d-1 which would enable to maintain all energy requirements of the feed pump, mixing and heating of the reactor contents. In addition to this, 71% of the energy requirement for recirculating the reactor content through the membranes would also be recovered.  相似文献   
10.
春尺蠖羽化发蛾特性研究表明,发蛾期与气温密切相关。邻近城区比郊外大田发蛾期早7~10d;发蛾前期雄蛾多于雌蛾,以后雌蛾增多;成虫为全日程羽化出土,雌雄性比为1:1.42;雌蛾交尾最多可达3次,雄蛾仅1次。应用佳多频振式杀虫灯诱捕春尺蠖雄蛾数量大。灯距120m范围内,树干表皮单位面积上的有效卵率较无灯对照区下降了24%~61.5%,控害效果显著。  相似文献   
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