Effects of Xylooligosaccharide(XOS)and Probiotics(PRO)on Production Performance,Egg Quality and Intestinal Short-chain Fatty Acids of Laying Hens in Late Laying Period

[Objective]The paper was to study the effects of xylooligosaccharide(XOS)and probiotics(PRO)and their interaction on the production performance,egg quality and intestinal short-chain fatty acids of laying hens in late laying period.[Method]A total of 36074-week-old Romain brown laying hens were randomly divided into four groups,six replicates each group and 15 chickens each replicate.The trial lasted 63 d.The laying hens in control group(CON)were fed with basal diet,and those in experimental groups were fed with the basal diets adding with 150 mg/kg XOS(XOS group),100 mg/kg probiotics(PRO group),150 mg/kg XOS+100 mg/kg probiotics(XOS-PRO group).[Result]Compared with the control group,the laying rate,daily egg production,yolk ratio,colonic acetic acid and caecal propionic acid in XOS group increased significantly(P<0.05),and the feed gain ratio decreased remarkably(P<0.05).PRO had no significant effect on the production performance and egg quality of laying hens in late laying period(P>0.05),but significantly increased colonic acetic acid(P<0.05).XOS and PRO had no interaction effect on the production performance,egg quality and intestinal short-chain fatty acids of laying hens in late laying period(P<0.05).[Conclusion]Adding XOS to the diet of laying hens in late laying period could increase the content of short-chain fatty acids in the hindgut of laying hens,and effectively improve the production performance and egg quality of laying hens in late laying period.Adding PRO to the diet did not significantly improve the production performance and egg quality of laying hens,and there was no interaction effect between XOS and PRO.

Mechanism of the Effect of Bacillus coagulans on Production Performance of Laying Hens in Late Laying Period

[Objective]The paper was to investigate the mechanism of Bacillus coagulans preparation in improving production performance of laying hens in late period of laying.[Method]A total of 648 individuals of"Jingfen 1"laying hens(66 weeks of age)in late period of laying were randomly divided into four groups,six replicates each group,and each group had 27 individuals of laying hens.The laying hens in control group were fed with basal diet,and those in experimental groupsⅠ,Ⅱ and Ⅲ were fed with the basal diets added with 3.33×10^6,1×10^7,3.33×10^7 CFU/g B.coagulans,respectively.The pretrial lasted one week,and the formal test lasted eight weeks.[Result]Compared with the control group,the laying rate in group Ⅰ increased significantly,and the feed-gain ratio in experimental group Ⅱ decreased noticeably while the spleen index increased remarkably;the alkaline phosphatase activities and blood calcium content in experimental groups Ⅰ,Ⅱ and Ⅲ increased significantly(P<0.05),while the triglyceride content decreased remarkably(P<0.05);the urea content in experimental groups Ⅰ and Ⅱ decreased obviously(P<0.05).Adding B.coagulans significantly increased the specific activity of amylase,lipase and protease in various intestinal mucosa of small intestine(P<0.05);adding B.coagulans significantly increased the content of follicle-stimulating hormone(FSH)and estradiol(E2),and significantly increased the mRNA expression of follicle stimulating hormone receptor gene(FSHR).[Conclusion]B.coagulans preparation could significantly improve the production performance of laying hens in late period of laying;appropriately enhance the immune capacity of laying hens;improve the serum biochemical indicators;increase the activity of digestive enzymes in the small intestine;and promote the release of gonadal hormone and the mRNA expression of FSHR gene in the ovary.

Effects of Dietary Energy Density in the Dry Period on the Production Performance and Metabolism of Dairy Cows

Thirty healthy Holstein dairy cows in the dry period were randomly divided into three groups and fed diets with different net energy for lactation (group A: 1.2 Mcal/kg DM, group B: 1.3 Mcal/kg DM, and group C: 1.4 Mcal/kg DM) for 8 weeks prepartum. Thereafter, dairy cows were fed a diet of the same formulation (1.66 Mcal/kg DM) for 12 weeks postpartum. The effects of different dietary energy densities in the dry period on postpartum performance and metabolic parameters of dairy cows were observed. Milk yield was reduced by 14.5% in the low-energy diet group;however, there were no differences in milk composition between the three groups. Postpartum plasma β-hydroxybutyrate, non-esterified fatty acid, growth hormone, and glucagon levels were significantly decreased whereas leptin and neuropeptide levels were elevated in the low-energy diet group. Moreover, body fat mobilization was attenuated, and the decline in postpartum body condition was reduced in the low-energy diet group, thus effectively reducing the postpartum negative energy balance.

Role of Periodic Input Composition and Sweeping Gas for Improvement of Hydrogen Production in a Palladium Membrane Reactor by Partial Oxidation of Methane

The partial oxidation of methane under periodic operation over Ni/y/-Al2O3 catalyst was investigated in a Pd-membrane reactor. The effects of key parameters such as the inlet composition and the sweeping, gas on methane conversion and the hydrogen recovery are numerically estalallshed with two penodtc input ttmctlons. In order to analyze the effect of the inputs modulation, the reaction was performed under low steam to methane ratio at a mod-erate temperature and pressure. It was obtained that to achieve process intensification is to operate the process in a periodic way. The main results show that the periodic input functions can improve the performance of the process compared to the optimal steady state operation. Moreover, there is an optimum amplitude of manipulated inputs leads to a maximum of hydrogen recovery. It is noteworthy that the comparison between the predicted performancevia the sinusoidal and the＇square ways show that the better＇average performance was obtainedwith the square way.

Rumen microbiota succession throughout the perinatal period and its association with postpartum production traits in dairy cows:A review

The transition period for dairy cows usually refers to the 3 weeks pre-calving to the 3 weeks post-calving.During this period,dairy cows undergo metabolic and physiological adaptations because of their susceptibility to metabolic and infectious diseases.Poor feeding management under these circumstances may adversely affect the health and subsequent production performance of the cows.Owing to long-term adaptation and evolution,the rumen has become a unique ecosystem inhabited by a complex microbial community closely associated with its natural host.Dietary components are metabolized by the rumen microbiota,and volatile fatty acids and microbial protein products can be used as precursor substances for synthesizing meat and milk components.The successful transition of perinatal dairy cows includes changes in diet,physiology,and the rumen microbiota.Rumen microbial profiles have been confirmed to be heritable and repairable;however,adverse circumstances affect rumen microbial composition,host digestion and metabolism,as well as postpartum production traits of dairy cows for a certain period.Preliminary evidence indicates a close relationship between the rumen microbiota and animal performance.Therefore,changes in rumen microbes during the transition period and the intrinsic links between the microbiota and host postpartum phenotypic traits need to be better understood to optimize production performance in ruminants.

1-Butene isomerization and metathesis over Mo/mordenite-alumina: Factors influencing product distribution and induction period

Effects of space velocity, reaction temperature and support acidity on product distribution and induction period in 1-butene isomerization and metathesis over Mo/mordenite-alumina were investigated. As revealed by the catalytic performance results, induction period and objective product were closely related to the reaction conditions. Lower space velocity led to longer induction period and higher propene yield. The optimal reaction temperature for propene production is around 150 ~C and it shifted to 100 ~C for ethene production. 1-Butene auto-metathesis predominated in the reaction network if the support with lower degree of sodium exchanged. And propene gradually became the dominant product upon increasing the support sodium exchange degree. 6Mo/H100Na0M-30A1 catalyst with a support of full sodium exchange degree exhibited the highest propene yield.

FLUCTUATION OF AGROCLIMATIC ZONES AND ITS IMPACT ON AGRICULTURAL PRODUCTION IN CHINA

Accumulated temperature above 100℃ (Σ t) and minimum annual temperature (Tm) are the major indexes for demarcating agroclimatic thermal zones. The paper calculated the return period (τ) of Σ t and Tm, and the shift ofΣ t-and Tm-isopleths with T. The results show: (1) According to the magnitude of shift of Σ t-and Tm-isopleths, in Northeast China, Inner Mongolia and northern Xinjiang the fluctuation of thermal resources in growing season from year to year is the greatest and strongly impacts the yield of annual thermophilous crops, but in the Changjiang River basin the fluctuation of the low temperature in winter is the greatest and seriously injures the perennial subtropical tree crops. ( 2) In the anomalous cool summer year with t = 30, the northern boundaries of the southern subtropical, northern subtropical and warm temperate zones and the southern boundary of the frigid temperate zone in China could be expected to shift southward 150, 220, 250 and 300 km from their normal positions,

Improved Algebraic Model for Serial Production Lines with Limited Buffer Sizes

The ordered event model is improved to describe serial production lines with limited buffer sizes. The improved model hasthe same computational burden as the original one and can be constrUcted directly according to given principles. Several simulationexamples are cited to verify this improved model. Extensions and open problems are also indicated. By means of this new model, serialProduotion lines with limitations of resources can be stUdied analytically.

A Typical Production and Elimination Process of Particles in Beijing during Early 2008 Olympic Games

[Objective] The aim was to discuss he produce and elimination rules of particles in Beijing during early 2008 Olympic Games. [Method] Based on the analysis of particulate matter online observation data and meteorological data during the corresponding period in Chinese environmental science college, Hysplit Back trace model and Numerical weather prediction graphs, and combined with the different analytical methods on meteorological flow fields, a typical process of particles in Beijing during early 2008 Olympic Games was studied. [Result] The results indicated that during the ascent stage of PM2.5 concentration, the PM showed gradually aging phenomena; the process controlled by large scale synoptic system mainly. And the weak wind and the high humidity were not in favor of dispersion; the prolonged southerly air mass to bring the pollutant of Hebei, Taijin and Shandong to Beijing; mixing height and temperature curve took the importance role to the pollution. [Conclusion] The study provided theoretical basis for the discussion on factors influencing the production and elimination of particles in the air pollution process.

Investigation of Red Meat Production in Turkey by ANOM Test

When comparing more than two groups means, the analysis of means （ANOM） can be used as an alternative to the one-way analysis of variance （ANOVA） F test. The ANOM provides a ＂confidence interval type of approach＂ that allows it to determine which, if any, of the x groups has a significantly different mean from the overall average of all the group means combined. The aim of this study was to show the application of a statistical technique （ANOM）, mostly used by agriculture, to determine differences between red meat production by period in Turkey. The production quantities of goat meat, mutton, buffalo meat and beef between the years 2010 and 2016 according to the period were taken from Turkish Statistical Institute （TSI）. As a result, the difference between meat productions was found to be significant.

Effects of Supplementation with <i>Saccharomyces cerevisiae</i>and Its Fermentation Products on Production Performance and Its Mechanism in Perinatal Dairy Cows

The aim of this study was to investigate the effects of Saccharomyces cerevisiae and its fermentation products on performance, blood hormone levels and rumen floral composition in peripartum dairy cows. Sixty perinatal cows were selected and allocated to two groups according to parity and expected date of delivery. Each group was supplemented with Saccharomyces cerevisiae and its fermentation product 0 or 100 g. The results showed that Saccharomyces cerevisiae and its fermentation products could significantly increase the feed intake of peripartum dairy cows (P < 0.01), increase the lactose content after 21 days postpartum (P < 0.01), and tend to increase milk production (P = 0.052). There was no significant effect on other milk components, the apparent digestibility of nutrients. There was a tendency to increase milk production and reduce the number of somatic cells in milk;increase blood levels of glucagon (P < 0.01) and β-hydroxybutyrate (P = 0.01), reducing the insulin content (P = 0.02). Saccharomyces cerevisiae reduced the abundance of rumen microbes in peripartum dairy cows but had no effect on rumen microbial diversity. Compared with the control group, the supplemented group showed reductions in the abundance of genera Bacillus (P = 0.03), Butyrivibrio (P = 0.01), Denitrobacterium (P = 0.01), and Mogibacterium (P < 0.01), Porphyromonas (P = 0.05), Saccharofermentans (P < 0.01), Sphaerochaeta (P = 0.02), Streptococcus (P = 0.04) and other genera. There were significant increase in the content of Acidaminococcus (P = 0.03), Allisonella (P < 0.01), Bulleidia (P < 0.01), Corynebacterium (P = 0.01), Dialister (P < 0.01), Faecalibacterium (P = 0.02), Faekalitalea (P = 0.03), Fibrobacter (P = 0.04), Flavobacterium (P = 0.03), Kandleria (P < 0.01), Paraprevotella (P < 0.01), Pyramidobacter (P = 0.05), Roseburia (P < 0.01), Succinivibrio (P < 0.01) and other genera. The main metabolic pathways such as tryptophan metabolism and steroid hormone biosynthesis in perinatal dairy cows were determined for Saccharomyces cerevisiae and its fermentation products.

Multi-Objective Production Planning Using Lexicographic Procedure

This paper presents a multi-objective production planning model for a factory operating under a multi-product, and multi-period environment using the lexicographic (pre-emptive) procedure. The model objectives are to maximize the profit, minimize the total cost, and maximize the Overall Service Level (OSL) of the customers. The system consists of three potential suppliers that serve the factory to serve three customers/distributors. The performance of the developed model is illustrated using a verification example. Discussion of the results proved the efficacy of the model. Also, the effect of the deviation percentages on the different objectives is discussed.

新时期我国农业生产性服务业的创新路径与策略

近年来,我国农业生产性服务业在政策扶持下迅速发展,农业机械装备总量与作业水平持续提升,服务主体与业务范围日趋多元,服务形式不断创新,规模服务主体组织带动农户优势凸显,农业生产性服务的功能作用不断升级。然而,该领域仍面临诸多挑战,如产业仍处于辅助性地位、服务供给不足、机械化作业环节发展不均衡、服务组织数量和融合度不足以及服务短板突出。为应对这些挑战,提出新时期的发展策略:健全工作推进机制;建设公共服务平台,创新农业生产性服务主体合作方式;引导农业生产性服务业规范发展,推动各地建立服务标准;加大政策落实力度,创新农业生产性服务业支持方式;加快培育有实力的服务组织,创新服务供给形式;完善农业基础设施,加快补齐服务短板;切实发挥村集体在推进适度规模经营中“统”的作用。

老油田“3+2”大幅度提高采收率技术内涵、机理及实践

传统方式的化学驱项目一般采取“2+3”的协同方式,也就是先通过水驱井网调整一次到位,再实施化学驱,受剩余油认识和预测精度的影响,会出现部分低产低效井,化学驱含水谷底平台期短,提高采收率幅度有限。为此,胜利油田通过基础攻关和探索实践,创新提出了化学驱与动态优化调整加合增效的“3+2”大幅度提高采收率技术,该技术是指在化学驱过程中,充分发挥和利用驱油体系扩大波及体积、提高驱油效率、调整动态非均质性的特点,主动培育、壮大动态剩余油富集区(“油墙”),适时井网调整、重构流场、均衡注采,高效动用、采出“油墙”,最大程度延长化学驱含水谷底平台期,实现三次采油和二次采油(“3+2”)适配优化、大幅度提高采收率的目的。通过大量物理模拟和数值模拟研究,明确了“井网-驱油剂-剩余油”适配优化提高采收率的机理。该技术在胜坨油田二区东三段5砂组进行了应用,通过优化“3+2”井网调整方式、驱油体系和注入参数等,预计区块含水谷底平台期从3 a延长至8 a,最终采收率为60.5%,比原方案采收率再提高7.5百分点。该技术是老油田大幅度提高采收率的关键技术,可以为中外同类型油藏延长化学驱见效高峰期提供指导和借鉴。

多参数回归物质平衡法在水驱气藏气井生产动态预测中的应用

物质平衡法在水驱气藏气井生产动态指标预测中面临2项难题,即产能方程的建立和水侵量计算,影响指标预测精度。针对存在的问题,通过理论推导及经验回归,研究产能方程系数和气层压力、水侵量和气层总压差、产水量与产气量之间的变化规律。建立一种新的多参数回归物质平衡法:包括3个基础方程(水驱气藏物质平衡方程、二项式产能方程、井筒管流方程)和4个经验关系式(二项式产能方程系数A与气层压力、二项式产能方程系数B与气层压力、累计水侵量与气层总压差、累计产水量与累计产气量)。结果表明,多参数回归物质平衡法立足气井的生产动态数据,简化了产能方程建立和水侵量计算过程。经过实践检验,平均误差在5%以内,该方法满足现场实际要求。

碳交易如何影响绿色低碳发展?——基于多期DID与连续DID的经验研究

碳交易如何影响以绿色全要素生产率为核心指标的绿色低碳发展,需进行实证检验。基于2005—2019年中国省际面板数据,运用多期DID模型评估碳交易对绿色低碳发展的影响及其作用机制。结果表明:碳交易促进了试点地区绿色低碳发展,在经过安慰剂、PSM-DID、剔除用能权交易试点样本等一系列稳健性检验后,结论仍成立;碳交易实施对能源结构优化、产业结构升级与技术进步具有正向影响,绿色能源消费占比增加、高技术产业结构提升与技术进步是碳交易提高试点地区绿色低碳发展水平的主要机制。构建连续DID模型,研究碳交易规模对绿色低碳发展的影响,发现碳交易规模扩大对绿色低碳发展水平具有正向影响。研究结论为碳交易助力绿色低碳发展提供了经验支持,也为区域碳市场及全国统一碳市场的进一步扩容提供了有价值的启示。

植物不同生长期成分含量变化研究

综述了植物不同生长期多酚、多糖、氨基酸和蛋白质、萜类和挥发性成分含量变化的研究现状,为药材质量评价、确定最佳采收期、合理施肥、果蔬质量控制、副产物的合理开发利用等提供理论依据。

致密砂岩气藏稳产后期动用效果评价与动用潜力分析:以子洲气田山2气藏为例

以子洲气田山2气藏为例,利用钻井及生产动态资料,通过对地质储量、动储量、累产气、累产水和动静储量比的计算与分析,采用综合评判指数法和类比法,详细评价了山2致密砂岩气藏动用效果和动用潜力。结果表明:山2气藏平面动用严重不均衡。7个井区中,主砂体带中部的榆30井区动用效果最好,属Ⅰ类动用区;主砂体带南部的洲3和北部榆81井区动用效果中等,为Ⅱ类动用区;主砂体周边的榆69、榆48、麒麟沟和榆29井区动用效果差,属Ⅲ类动用区。初步预测山2气藏整体动用潜力为198.1×10^(8) m^(3)。其中,Ⅲ类区的动用潜力为174.7×10^(8) m^(3),占88.2%,是山2气藏后续挖潜重点。

新中国初期海南黎族苗族地区提高农业生产力措施研究

海南全岛解放后,党和政府根据黎族苗族地区经济社会文化实际,制定了一系列以经济-文化为主的政策措施,促进了海南黎族苗族地区由初期农耕社会-狩猎采集社会向农耕社会的转化,使得其农业生产力水平迅速提高、基础设施迅速改进、教育文化水平迅速提升、人民生活水平显著改善,迅速地拉近了与其他地区经济社会发展水平的距离,并为今后进一步发展奠定了基础。实践证明,这些政策措施,既符合农业社会的发展规律,又充分联系了黎族苗族地区的实际,因而在当时取得了良好的政策效益,其亦给当今推动海南黎族苗族地区的发展提供了很好的借鉴。

大数据技术应用能抑制企业避税吗——基于国家级大数据综合试验区的分析

基于国家级大数据综合试验区试点政策,利用2013—2022年沪深A股上市公司数据,采用多期DID模型,研究了大数据技术应用对企业避税的影响。研究表明,大数据技术应用显著抑制了企业避税,该结论在经过PSM-DID、替换被解释变量、排除政策干扰等一系列稳健性检验后依然成立;机制分析发现,大数据技术应用有助于提升信息透明度和企业生产效率进而抑制了企业避税。异质性分析表明,大数据技术应用对东部地区和非高科技企业避税抑制效果更为显著。本文的研究结论不仅丰富了企业避税影响因素的相关研究,而且揭示了国家级大数据综合试验区政策所产生的积极治理效应,为后续持续推进大数据技术应用提供理论支持与经验证据。