Board-invited review: Sensitivity and responses of functional groups to feed processing methods on a molecular basis

In complex feed structures, there exist main chemical functional groups which are associated with nutrient utilization and availability and functionality. Each functional group has unique molecular structure therefore produce unique molecular vibration spectral profile. Feed processing has been used to improve nutrient utilization for many years. However, to date, there was little study on processing-induced changes of feed intrinsic structure and functional groups on a molecular basis within intact tissue. This is because limited research technique is available to study inherent structure on a molecular basis. Recently bioanalytical techniques： such as Synchrotron Infrared Microspectroscopy as well as Diffuse Reflectance Infrared Fourier Transform molecular spectroscopy have been developed. These techniques enable to detect molecular structure change within intact tissues. These techniques can prevent destruction or alteration of the intrinsic protein structures during processing for analysis. However, these techniques have not been used in animal feed and nutrition research. The objective of this review was show that with the advanced technique, sensitivity and responses of functional groups to feed processing on a molecular basis could be detected in my research team. These functional groups are highly associated with nutrient utilization in animals.

Theoretical evaluation on nitrogen removal of step-feed anoxic/oxic activated sludge process

Evaluation on nitrogen removal of step-feed anoxic/oxic activated sludge process at the standpoint of reaction kinetics and process kinetics was conducted. Theoretical biological nitrogen removal efficiency was deduced based on the mass balance of nitrate in the last stage. The comparison of pre-denitrification process and step feed process in the aspects of nitrogen removal efficiency, volume of reactor and building investment was studied, and the results indicated that step-feed anoxic/oxic activated sludge process was superior to pre-denitrification process in these aspects.

Automatic control strategy for step feed anoxic/aerobic biological nitrogen removal process

Control of sludge age and mixed liquid suspended solids concentration in the activated sludge process is critical for ensuring effective wastewater treatment. A nonlinear dynamic model for a step-feed activated sludge process was developed in this study. The system is based on the control of the sludge age and mixed liquor suspended solids in the aerator of last stage by adjusting the sludge recycle and wastage flow rates respectively. The simulation results showed that the sludge age remained nearly constant at a value of 16 d in the variation of the influent characteristics. The mixed liquor suspended solids in the aerator of last stage were also maintained to a desired value of 2500 g/m3 by adjusting wastage flow rates.

Optimization of Screening Method for Feed Nutrition and Processing Conditions

On the basis of regressional relationship between nutritional indexes and technological conditions,when confronted with feed quality that contains multiple nutritional indexes,a comprehensive equation of evaluating feed quality was developed by using fuzzy mathematical method at first in this study,and then the optimum technological conditions were established by introduction of statistical frequency analysis method pursuant to the comprehensive evaluating equation mentioned above compared with conventional multi-aim nonlinear programming,this method can lead to easy solutions,and also can make adjustment of the importance of nutritional indexes to feed quality according to practical considerations.An example was given of soybean extruding to show how the method worked.

Simultaneous nitrification and denitrification in step feeding biological nitrogen removal process

The simultaneous nitrification and denitrification in step-feeding biological nitrogen removal process were investigated under different influent substrate concentrations and aeration flow rates. Biological occurrence of simultaneous nitrification and denitrification was verified in the aspect of nitrogen mass balance and alkalinity. The experimental results also showed that there was a distinct linear relationship between simultaneous nitrification and denitrification and DO concentration under the conditions of low and high aeration flow rate. In each experimental run the floc sizes of activated sludge were also measured and the results showed that simultaneous nitrification and denitrification could occur with very small size of floc.

Optimization of Dividing Wall Column with Heat Transfer Process Across the Wall for Feed Properties Variation

This paper investigates the thermal-coupled effect across the wall and the optimal heat transfer region of the wall for enhancing the energy saving effect of dividing wall column (DWC), and also studies the effects of feed thermal condition (q) and middle component composition of feed (cB) on the heat transfer process, the optimal heat transfer region, and the maximum heat transfer quantity across the wall. The simulation results show that the maximum heat transfer quantity across the wall and the potential for energy saving increase with the increase of q, while with the limitation of temperature difference across the wall, the beneficial heat transfer effect between certain range of stages, which are involved in the optimal heat transfer region, cannot be realized completely for a specific value of q. Besides, compared with q, a changing cB does not change the degree of realizing the beneficial heat transfer effect, but can bring about the variation of liquid split ratio (RL) and vapor split ratio (Rv). Thus, for achieving a maximum energy-saving effect of DWC, different q and cB need to find its own corresponding suitable heat transfer process across the wall.

Aflatoxin Contamination and Rancidity in Locally Processed Commercial Fish Feeds and Ingredients along the Value Chain in Wakiso and Kampala Districts, Uganda

Aflatoxin contamination and rancidity in locally processed commercial fish feeds and ingredients along value chains is a Public and Animal health hazard. The study established the level of aflatoxin contamination, peroxide value (PV), Anisidine value (AnV), and their associated factors at storage areas among farmers, processors, traders, factories, and landing sites in the Wakiso and Kampala districts. The value chain actors were purposively selected in a cross-sectional study based on access to the feed store and the use of locally processed commercial fish feeds on farms. Data collected were statistically analyzed in SPSS version 20. All the samples (45) were positive for aflatoxin contamination and PV with 51% (23/45) of samples being contaminated with “above acceptable” aflatoxin levels and 66.6% (30/45) of samples with “above acceptable” PV. The overall percentage of “above acceptable” AnV was 11/29 (37.9%). Samples from factories were within acceptable contamination levels. Multivariate logistic regression analysis revealed no significant difference between aflatoxin contamination, peroxide, and Anisidine value with storage factors for locally processed commercial fish feeds and ingredients. The study recommended the purchase of fish feeds from factories and a larger study on storage factors responsible for aflatoxin contamination and rancidity in fish feeds in Uganda.

信息流广告的重定向策略研究:用户动态信息加工视角

信息流媒体平台的动态性和响应性,一方面赋予了用户自由筛选和屏蔽信息的权利,另一方面也让平台可以根据用户反馈及时调整后续信息的推送策略。当前,用户屏蔽信息流广告的行为非常普遍,然而传统广告回避的研究结论无法平移到信息流广告的重定向情境。本研究将从用户动态信息加工的视角出发,探讨用户在不同信息加工模式下的信息流广告屏蔽与重定向策略。通过对大量观察数据的挖掘分析并结合实验室实验,结果表明:对于处于快处理模式屏蔽信息流广告的用户,后续为其推送与屏蔽广告不同品类的产品广告能使其拥有更积极的广告态度;对于处于慢处理模式屏蔽信息流广告的用户,后续为其推送与屏蔽广告相同品类的产品广告能使其拥有更积极的广告态度。研究结论对信息流广告投放实践具有管理启示作用。

越桔豆粕复合发酵饲料添加剂制备工艺及抗氧化活性研究

本试验以中草药桔梗、红豆越橘叶以及豆粕为发酵原料,为制备绿色中草药饲料添加剂优选制备工艺。采用枯草芽孢杆菌进行固体发酵,以总多酚含量、总游离氨基酸含量及ABTS自由基清除率为评价指标,通过单因素试验考察发酵温度、发酵时间、原料比例、含水量、接菌量等条件,并采用响应面Box-Behnken设计建立模型,对发酵工艺进一步优化。结果表明:最佳发酵工艺为红豆越橘叶和桔梗比例1:0.8、含水量65%、接菌量8%、发酵温度37℃、发酵时间56 h。在此工艺下,总多酚含量5.86 mg/g、总游离氨基酸含量17.95 mg/g、ABTS自由基清除率66.28%。在单因素试验基础上,运用Box-Behnken响应面法对越桔豆粕复合物发酵工艺进行优化,响应面法预测理论值与实际值接近,可为后续研究提供稳定可行的制备工艺。

The Applied Research of Soybean Peptide in Feedstuffs

The soybean peptide has the trait of amino acid balance,digestible and easy to absorb,low allergy and low antigenicity.Furthermore,it also showed the feature of good mobility and thermal stability at high concentrations.This paper seeks to study the processing and nutritional characteristics of soybean peptide.And on that basis to lucubrate soybean peptide as a safe,efficient feedstuffs additives.The aim is to improve the feedstuffs quality.

Enhanced a novel β-agarase production in recombinant Escherichia coli BL21(DE3) through induction mode optimization and glycerol feeding strategy

Agarases are hydrolytic enzymes that act on the hydrolysis of agar and have a broad range of applications in food,cosmetics and pharmaceutical industries. In this study, a glycerol feeding strategy based on induction mode optimization for high cell density and β-agarase production was established, which could effectively control acetate yield. First, exponential feeding strategy of glycerol with different overall specific growth rates（μ） was applied in the pre-induction phase. The results showed that the low μ（μ=0.2） was suggested to be the optimal for cell growth and β-agarase production. Second, the effects of induction temperature and the inducer concentration on cell growth and β-agarase production were investigated in the post-induction phase. When induced by isopropyl-β-d-thiogalactoside（IPTG）, the strategy of 0.8 mmol/L IPTG induction at 20℃ was found to be optimal for β-agarase production. When cultivation was induced by continuous lactose feeding strategy of 1.0 g/（L·h）, the β-agarase activity reached 112.5 U/mL, which represented the highest β-agarase production to date.Furthermore, the β-agarase was capable of degrading G. lemaneiformis powder directly to produce neoagarooligosaccharide, and the hydrolysates were neoagarotetraose（NA4） and neoagarohexaose（NA6）. The overall research may be useful for the industrial production and application of β-agarase.

Effect of Low Feed Rate FSP on Microstructure and Mechanical Properties of Extruded Cast 2285 Aluminum Alloy

Friction stir processing （FSP）, a variation of FSW （friction stir welding） is an emerging surface engineering technology that can locally eliminate casting defects and refine microstructures, thereby improving the mechanical properties of material. FSP can also produce fine grained microstructures through the thickness to impart superplasticity. The technology involves plunging a rapidly rotating, non consumable tool, comprising a profiled pin and larger diameter shoulder, into the surface and then traversing the tool across the surface. The pin and the shoulder friction heat the surface which alters the grain structure in the processed area thereby improving the mechanical properties. This paper presents the effects of FSP on microstructure and mechanical properties of extruded cast 2285 aluminum alloy at three different feed rates viz. 10, 12 and 15 mm/min. With the increase in the feed speed the material was observed to have increased impact strength. FSP also increased the tensile and yield strengths with increases in hardness and ductility values also. The observation has been listed in detail and pictorially represented.

大脑半球大面积脑梗死患者血管内低温治疗时实现早期幽门后喂养的流程优化研究

目的优化大脑半球大面积脑梗死患者血管内低温治疗时实现早期幽门后喂养的护理流程并分析其应用效果。方法采用便利抽样法,选取2019年1月—2021年12月连续入住北京某三甲医院神经科ICU行血管内低温治疗的53例首发大脑半球大面积脑梗死患者为研究对象,其中对照组为2019年1月—2020年5月的25例患者,实验组为2020年6月—2021年12月的28例患者。实验组采用优化护理流程,对照组采用常规护理流程。比较两组患者鼻肠管置入成功率、置管相关并发症发生率、置管总耗时及血管内低温治疗启动耗时。结果实验组的鼻肠管置入成功率为85.7%,高于对照组(P<0.05);置管总耗时(48.84±19.12)min,较对照组明显缩短(P<0.05);实验组鼻肠管置入时鼻咽黏膜出血、消化道出血及心律失常的发生率低于对照组(P<0.05);两组间血管内低温启动耗时差异无统计学意义(P>0.05)。结论大脑半球大面积脑梗死患者血管内低温治疗期间实现早期幽门后喂养的优化流程可确保血管内低温治疗按时启动,有效缩短鼻肠管置管耗时,提高置管成功率,减少置管相关并发症的发生。

我国饲料粮供给区域差异时空演化特征及影响因素分析

文章旨在探究我国饲料粮供给区域差异时空演化特征及其影响因素。选取2005—2021年我国31个省份的月度面板数据,使用空间自相关和冷热点分析法深入探究饲料粮供给区域差异时空演化特征,进一步通过泰尔指数与空间杜宾模型深入剖析其驱动因素。结果显示,饲料粮供给冷点与热点区域均呈现集中态势,且其局部空间关联性较为明显。饲料粮供给空间分布格局检验结果表明,北部沿海地区多为“低-低”型区域聚集区,东北、东南沿海与西南地区多为“高-高”型区域聚集区。泰尔指数与结构性原因分析显示,饲料粮供给水平呈现明显正向空间溢出效应,其中组内差异是区际差异的关键因素。空间杜宾模型结果表明,土地生产率、交通运输水平、粮食生产机械投入和饲料粮加工水平是饲料粮供给水平的重要影响因素。

复合益生菌固态发酵断奶仔猪配合饲料工艺参数的优化及品质评定

利用复合益生菌联合发酵技术对断奶仔猪配合饲料进行固态厌氧发酵,通过不同的工艺参数:接菌量、发酵温度、发酵水分和发酵时间,探讨对发酵饲料品质的影响。结果显示:不同的参数对配合饲料品质有明显影响。采用5.0%接种量、35%发酵水分、37℃发酵温度和72 h发酵时间,可有效提高配合饲料中粗蛋白、乳酸、游离氨基酸的含量和益生菌数量,降低发酵饲料霉菌数量,改善发酵饲料风味和品质,防止饲料霉变和虫蛀。发酵后的配合饲料颜色金黄、气味芳香、质地松散而不黏连。

进水分配比对分段进水PN/A工艺脱氮性能影响

以预脱碳污水和市政污水作为目标污水,建立了好氧段分段进水的新模式,通过调整进水分配比来优化好氧段C/N,以期实现短程硝化-厌氧氨氧化(PN/A)工艺在实际工况下的稳定运行.采用4组以好氧/缺氧/好氧/缺氧(O/A/O/A)模式运行的序批式反应器(SBR),R1、R2、R3及R4以进水分配比(预脱碳污水:市政污水)分别为1:0、2:1、1:1及1:2的分段进水模式运行.结果表明,R1未能实现PN/A工艺,总氮去除率(NRE)仅为60.2%.随着进水分配比不断下降,R2、R3、R4分别在第34,30及36d实现PN/A工艺,NRE分别达到71.8%、80.3%及74.1%.其中R3系统处理性能最好且最稳定,厌氧氨氧化贡献率达到83.9%.污泥沉降性与粒径最佳.此外,高通量结果显示氨氧化菌(Nitrosomonas)和厌氧氨氧化菌(Candidatus_Kuenenia)丰度分别为2.74%和12.17%,且与好氧异养菌(AHB)形成了良好的协同作用.因此,分段进水模式在进水分配比为1:1时有利于实现稳定的PN/A工艺,此时各功能微生物可得到较好富集与平衡.

酶菌协同发酵中草药渣工艺优化研究

本研究旨在筛选适宜的酶菌发酵制剂并建立优化发酵条件,以改善和提高中草药渣的营养价值和生物活性含量。采用三因素三水平正交试验设计,设置三个变量分别为初始含水量(45%、50%、55%)、发酵温度(35、37、40℃)和发酵时间(24、48、72 h),研究纤维素酶、植物乳杆菌和枯草芽孢杆菌协同混合发酵对药渣营养成分和生物活性含量变化的影响,确定适宜的工艺参数。研究结果表明:酶菌协同发酵咽炎片药渣的最佳发酵工艺条件为初始水分含量55%,发酵温度40℃,发酵时间72 h。黄曲霉毒素B1和呕吐毒素均符合我国饲料卫生生产标准。在此发酵工艺条件下有助于提升发酵药渣的营养价值。

生物发酵农作物秸秆及其在反刍动物饲料中的应用

我国农作物秸秆资源丰富,但大部分被直接还田或焚烧,造成资源浪费。农作物秸秆饲料化利用作为农作物秸秆利用途径之一,对缓解粗饲料资源紧张、促进畜牧业可持续发展具有重大意义。但因为秸秆粗纤维含量高和适口性差的特性,直接作为饲料利用,营养价值较低,生物发酵处理可以有效提高秸秆的营养价值和利用率。文章从农作物秸秆饲料化利用现状、生物发酵技术在农作物秸秆饲料化中的应用、生物发酵农作物秸秆在反刍动物生产上的应用研究等方面进行综述,为农作物秸秆的资源化利用提供参考依据。

青贮饲料的制备及其在畜牧业中的应用

随着畜牧业的持续繁荣,饲料青贮技术也得到了快速的发展。如今,青贮饲料在养殖领域的运用已经变得相当普遍,其应用范围已经逐步扩展至整个畜牧生产行业。高品质的青贮饲料不仅能够显著提升畜产品品质,在保护生态环境方面还发挥着重要作用。因此,深入研究高质量青贮饲料的生产工艺和利用方式显得尤为重要。该文详细叙述优质青贮饲料的生产流程,并进一步探讨了其在畜牧业中的广泛应用及其对产业发展的重要贡献。

新疆畜禽饲料资源中粗蛋白含量的调查研究

试验旨在研究新疆不同地州间各种常规饲料原料的粗蛋白含量和分布情况,为各地州饲粮合理配制提供科学依据。对新疆全区14个地州的13种115个主要畜禽饲料原料在科学采样的基础上进行粗蛋白含量测定。对同类不同种饲料样品和不同饲料样品的粗蛋白含量进行单因素方差分析,比较不同饲料原料中粗蛋白含量的差异及不同地区之间的差异。结果表明:不同原料除青贮玉米外,干物质含量都在92%以上;粮油加工副产物的粗蛋白含量最高,粮食作物秸秆粗蛋白含量最低。8个地州采集玉米样品中喀什的粗蛋白含量最高。全疆各地州的各种类饲料原料中粗蛋白含量相互之间变化非常大,因此,实际应用中要充分考虑到不同区域饲粮中粗蛋白含量,为精准配方、精准营养提供技术支撑。