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61.
Effects of zinc oxide nanoparticles on the egg quality,immune response,zinc retention,and blood parameters of laying hens in the late phase of production 下载免费PDF全文
M. Abedini F. Shariatmadari M. A. Karimi Torshizi H. Ahmadi 《Journal of animal physiology and animal nutrition》2018,102(3):736-745
The objective of this study was to evaluate the effects of dietary supplementation with zinc oxide nanoparticles (ZnO‐NPs) on the performance, egg quality, Zn retention, immunity responses, superoxide dismutase activity (SOD), egg malondialdehyde (MDA) content, and serum parameters in laying hens in the late phase of production. A total of 288 laying hens at 64 weeks of age were randomly assigned to 4 treatments with 6 replicates, and 12 birds within each group. Experimental diets included a corn‐soybean meal‐based diet (without Zn supplementation) and a basal diet supplemented with 80 mg/kg of Zn‐oxide, ZnO‐NPs, and Zn‐methionine. The results indicated that egg production and egg mass were significantly higher in the Zn‐methionine and ZnO‐NPs groups (p < .05). Also, eggshell thickness and shell strength increased in the ZnO‐NPs group as compared with the other groups (p < .05). Moreover, Zn supplementation decreased egg loss (p < .05). There were significant differences among treatments in Zn deposition in tibiotarsus, liver, pancreas, eggs, and excreta (p < .01). Antibody titre, heterophil (%(, and phytohemagglutinin (PHA) were significantly higher in birds fed with Zn‐supplemented diets (p < .05). In treatments supplemented with ZnO‐NPs and Zn‐methionine, the SOD activity in the liver, pancreas, and plasma was greater as compared with the other treatments (p < .05). The MDA content in eggs was significantly reduced in groups supplemented with Zn (p < .01). Moreover, dietary Zn supplementation significantly affected serum total protein, albumin, glucose, alkaline phosphatase activity, carbonic anhydrase activity, and Zn level (p < .05). In conclusion, this study demonstrated that dietary supplementation with ZnO‐NPs can improve the performance of laying hens. Therefore, ZnO‐NPs can enhance zinc absorption in the intestine of aged layers and can be a more suitable source of zinc than regular Zn‐oxide in diets. 相似文献
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在地铁深基坑施工中,围护结构对基坑的安全起着至关重要的作用。本文依据合肥地铁一号线明光路站,施工过程中,由于车站3号出入口为出土口,原计划的第一道钢筋混凝土支撑无法实现,更改为钢支撑,通过有限元分析软件MIDAS-GTS\NX,建立二维模型进行数值模拟,对围护结构的变形和地表沉降进行分析,结果表明:第一道支撑采用钢支撑代替钢筋混凝土支撑对围护结构的侧移值影响不大,钢筋混凝土支撑控制地表沉降的效果要比钢支撑好,对今后类似工程变更提供依据。 相似文献
63.
利用5个锈病成株期抗性基因的KASP标记Sr2_ger9 3p、Lr34jagger、CSTM4_67G、Lr68-2、VPM_SNP和抗赤霉病基因Fhb1的KASP标记TaHRC-KASP,对云南省育成的42个小麦品种(系)进行检测,旨在筛选出含有目标基因的优异小麦种质,为云南省持久抗病小麦新品种(系)的选育提供材料。结果表明,4个材料含兼抗型成株抗锈病基因Lr34/Yr18/Sr57,频率为9.52%;6个品种(系)含兼抗型成株抗锈病基因Lr67/Yr46/Sr55,频率为14.29%;7个材料含抗慢叶锈病基因Lr68,频率为16.67%;含兼抗型成株抗锈病基因Sr2/Yr30和成株抗叶锈基因Lr37的材料各有1个,频率均为2.38%;未检测出含抗赤霉病基因Fhb1的品种(系)。云麦69、云麦75、云麦56、宜麦1号和宜麦3号等兼有2个成株期抗锈病基因,可作为今后云南持久抗锈病育种的抗源材料。 相似文献
64.
原始云冷杉、红松林树木生长对氮沉降的响应 总被引:2,自引:0,他引:2
本文通过野外控制试验,设置4个梯度的施氮处理,分别为对照(CK,不加氮)、低氮(TL,5 g/(m2·a))、中氮(TM,10 g/(m2·a))、高氮(TH,15 g/(m2·a)),研究云冷杉红松林主要树种的径生长对氮沉降增加的响应。结果表明,枫桦径生长随氮添加梯度的增加出现了先促进后抑制的趋势;臭冷杉和红松径生长随氮添加梯度的增加而受到抑制,其中臭冷杉表现出明显的衰退现象甚至死亡;花楷槭则表现出较为复杂的响应,可能与该树种对不同梯度氮添加的响应机制不同有关。同时还发现,各处理、各树种的胸径大小与径生长量存在相关性,可能与树种年龄及其所处的生态位相关。研究表明,氮沉降改变树木生长速率和死亡率,可能影响地上生态系统碳库和整个生态系统碳循环。 相似文献
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The majority of dead organic material enters the soil carbon pool following initial incorporation into microbial biomass. The decomposition of microbial necromass carbon (C) is, therefore, an important process governing the balance between terrestrial and atmospheric C pools. We tested how abiotic stress (drought), biotic interactions (invertebrate grazing) and physical disturbance influence the biochemistry (C:N ratio and calcium oxalate production) of living fungal cells, and the subsequent stabilization of fungal-derived C after senescence. We traced the fate of 13C-labeled necromass from ‘stressed’ and ‘unstressed’ fungi into living soil microbes, dissolved organic carbon (DOC), total soil carbon and respired CO2. All stressors stimulated the production of calcium oxalate crystals and enhanced the C:N ratios of living fungal mycelia, leading to the formation of ‘recalcitrant’ necromass. Although we were unable to detect consistent effects of stress on the mineralization rates of fungal necromass, a greater proportion of the non-stressed (labile) fungal necromass C was stabilised in soil. Our finding is consistent with the emerging understanding that recalcitrant material is entirely decomposed within soil, but incorporated less efficiently into living microbial biomass and, ultimately, into stable SOC. 相似文献
68.
响应曲面法优化高粱挤压最佳操作参数的研究 总被引:1,自引:0,他引:1
以高粱为原料,研究系统操作参数,包括:物料含水率、喂料速度、螺杆转速、机筒温度对目标参数的影响,并以响应曲面法优化最佳操作参数,优化得到的最佳操作参数为:物料含水率15.77%,喂料速度26.97r/min,螺杆转速181.20r/min,五区温度158.28℃。 相似文献
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The aim of this study was to develop a novel oil-in-water (O/W) emulsion as adjuvant diluents (AD) for live vaccine against classical swine fever (CSF) that could effectively enhance the immune effect of vaccine.The AD was prepared by high-pressure homogenization technique.Formulations and preparation parameters were optimized with response surface design.Its stability, particle size, polydispersity (PDI) and Zeta potential were characterized.The humoral immune response and cellular immune response of the AD were evaluated with BALB/c mice by intramuscular injection.The particle size of the AD prepared by optimized formulation and parameters was 100.4 nm, PDI was 0.147, and Zeta potential was —28.7 mV.The experiment results showed that the AD had good stability.The AD was inoculated combined with live vaccine against CSF into BALB/c mice by intramuscular injection.The results showed that the live vaccine against CSF specific immune responses could be evoked in mice by co-inoculation with AD and vaccine.The cellular immune response levels in co-inoculated groups were significantly higher than control group (P<0.05), with obvious phenomena of higher levels of IFN-γ, IL-6 and IL-4 in serum.The result revealed that cellular immune capability significantly improved with the AD.The results strongly revealed that cellular immune capability significantly improved by introducing AD for effective immune-adjuvant for live vaccine against CSF. 相似文献