Finish Effect of Different Feeding Patterns on Weaned Lamb

Finish effect of four feeding patterns on weaned lamb was studied in the paper. The results showed that the performance of growing lambs by agricultural byproduct residual forage was superior to other feeding methods; too high proportion of straw in diet was unfavorable for finish lamb, and corn straw should be combined with complete feed to get better feeding effect.

Analysis of the radiation Resistance and Gain of Full-Wave Dipole Antenna for Different Feeding Design

This paper demonstrates the analysis of antenna pattern and gain for different designs of full-wave dipole antenna feeding techniques. Seven such techniques were studied and analyzed;symmetrical dual feeding in phase, symmetrical dual feeding out of phase, asymmetrical dual feeding in phase, asymmetrical dual feeding out of phase, symmetrical triple feeding in phase and symmetrical triple feeding out of phase. Symmetrical dual feeding in phase produced high gain as compared to the single and center-fed antennas. An improvement of about 3 to 3.5 dB was achieved comparing to center tap fed and off center fed. It was found that an asymmetrical dual feeding in-phase provides good performance, considering the directivity, pattern, and input impedance. A 2.46 dB gain has been attained. It was found that a symmetrical triple feeding provides an overall best performance with respect to gain, radiation pattern, beam width and input impedance.

“双循环”格局下中国饲料粮进口稳定性研究

“双循环”格局下适度进口已成为缓解国内饲料粮供需矛盾的现实选择。在有效利用国际饲料粮市场的同时,降低饲料粮进口的稳定性风险,既重要且必要。在对国内饲料粮供需形势精准判断的基础上,综合分析饲料粮进口的可获性与可供性,并采用香农熵指数法对饲料粮的进口来源稳定性进行评估。结果表明:国内饲料粮供需格局趋紧并呈现常态化发展趋势,供需缺口不断扩大,适度进口饲料粮是大势所需。总量上,世界饲料粮的供应潜力巨大;时点上,我国与国际饲料粮生产波动的相关性较弱。因此,利用国际市场弥补国内饲料粮的供需缺口是可行的。1992—2020年,我国饲料粮进口的稳定程度整体处于较低水平,其中,玉米、麦麸和大麦的变动幅度较大,大豆的波动幅度较小。在新一轮高水平开放格局下,亟须完善政策体系、优化进口结构、提高进口稳定性,构建“双循环”新发展格局下开放型的国家饲料粮安全保障体系。

Dietary Patterns of Children during the First Year of Life: A Cohort Study <br/>—Dietary Patterns of Children

Objective: To identify the dietary patterns of children during the first year of life. Methods: This is a longitudinal study of children born between September 2004 and April 2005 residing in Diamantina, MG, Brazil. Data were collected from children who were six, nine and twelve months of age. Data were collected at their homes using a questionnaire that included a socioeconomic and demographic profile of the family. Information on diet was obtained using 24 hour food recall. Principal Component Analysis was used to identify the dietary patterns. Results: Three dietary patterns were identified and denominated “Porridge”, “Pap” and “Family Food”. The most common dietary pattern was composed of milk, sugar and fortified flour and was negatively correlated with breastfeeding. The second dietary pattern was composed of tubers, vegetables and fruits. The third dietary pattern consisted of cereal, meat, beans and tea;this pattern was repeated at different ages, with some variation at the sixth month when artificial drinks were included and meat and tea were excluded. Conclusion: There was some variation in the dietary patterns of children;however, porridge was used predominantly in all studied ages. Information on dietary patterns may be useful for evaluating and redirecting food and nutrition policies.

基于OPLS-DA模型分析不同养殖方式下宁都黄鸡肌肉关键挥发性风味物质

为研究不同养殖方式下宁都黄鸡肌肉关键挥发性风味物质,将试验鸡随机分为笼养组和平养组,饲喂同一日粮。试验鸡达上市日龄时对鸡肉进行感官品尝评价和挥发性风味物质检测,并采用正交偏最小二乘-判别分析(orthogonal partial least squares-discriminant analysis,OPLS-DA)方法筛选与不同养殖方式相关的差异性风味物质。结果表明:平养组和笼养组共有的挥发性风味物质27种,主要为酚类、醇类和烃类。挥发性风味物质中,己醛、1-辛烯-3-醇、E-2-壬烯醛、正己醇、壬醛、2,3-戊二酮、癸醛、2,3-辛二酮、E-2-辛烯醛为具有显著性差异的挥发性风味物质。综上,这一研究可为地方鸡肉品质基于风味物质的评价提供科学依据。

Incidents with Dioxins and PCBs in Food and Feed-Investigative Work, Risk Management and Economic Consequences

The identification of contamination sources within the food chain with polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzo-furans (PCDFs), (“dioxins”), and PCBs is difficult and complex. PCDD/PCDF can be formed as unintentional compounds in a number of chemical processes as well as in almost every combustion process. PCBs were intentionally produced chemicals that were manufactured for decades before the ban in marketing and use in many countries around 1985. The pattern of occurrence can change from the original source in particular via feedingstuffs to food of animal origin as result of bioaccumulation. A number of examples illustrate the challenging detective work and key scientific aspects for identification of the sources, for support of the risk management and for performance of monitoring programs. The contamination of milk and milk products in European countries with dioxins was caused by compound feeds containing citrus pulp pellets from Brazil which had high dioxin levels as a result of the use of heavily contaminated lime used for neutralization. The Belgian dioxin crisis was caused by a feed additive heavily contaminated with PCBs which were discharged into a recycled fat used in the production of animal feed. Guar gum from India was contaminated with sodium pentachlorophenate and dioxins. Clay was found to be possibly highly contaminated with dioxins possibly formed by geothermal processes over time;use of such clay as feed additive or for human intake led to elevated dioxin levels in food and humans. Bioanalytical screening in combination with comprehensive physicochemical investigations led to the detection of brominated flame retardants and brominated dioxins in a feed additive. Buffalo milk was contaminated in Italy presumably caused by illegal deposition of waste. High PCB levels in fuel oil for drying of breadcrumb used as a feed ingredient caused a major dioxin crisis with pork meat in Ireland. Fatty acids for technical purposes originating from a biodiesel company were used for production of feed fat which contaminated parts of the food chain in Germany. In addition to effects on human and animal health these incidents also have serious economic consequences which could be mitigated by more frequent control on food and feed. Addressing both these issues, the European Community has developed a strategy to reduce the presence of dioxins and PCBs in the environment and in feed and food comprising the establishment of maximum and action levels.

Radiation characteristics of ring patch antennas with capacitive feed patch

Ring patch antennas have the characteristics of electrically small size as decreasing the width of the conducting portion compared to those of conventional patch antennas.In the ring patch antenna,using capacitive feed method is suitable for impedance matching.The effect of the size of the feed patch on the input impedance of the square ring patch antennas are analyzed and radiation patterns of the square ring patch antennas are compared to that of a square conventional patch antenna by the simulated results.

Comparative Analysis on Antenna Balun and Feeding Techniques of Step Constant Tapered Slot Antenna

This paper represents the performance analysis of the different shapes of antenna balun and feeding techniques for step constant tapered slot antenna. This work also addresses the benefits of antenna balun (circular and rectangular) along with two types of feeding techniques (Microstrip line L-shape and Microstrip line I-shape). The performance of the antenna for each technique is thoroughly investigated using Computer Simulation Technology (CST) Microwave Studio software simulation under the resonant frequency of 5.9 GHz. Results demonstrate that the proposed model is an effective tool for improving antenna performance. Moreover, an extensive comparison has been carried out between the two different shapes, with and without antenna balun and between two feeding techniques focusing on return losses, gain, directivity, and voltage standing wave ratio (VSWR).

“双循环”新格局下饲料产业经济的结构调整

当前,我国的饲料产业发展面临着国际、国内的双重挑战,推动“双循环”新发展格局,调整饲料产业经济结构,提高现代化发展水平,已成为我国重新塑造饲料产业优势,推动经济实现高质量发展的关键战略方向。本文主要分析了“双循环”新格局下对饲料产业的发展要求,明确了饲料产业经济的结构调整要素,并提出了饲料产业经济结构调整的具体策略,以期提高饲料产业在新时期的发展水平,为提高我国饲料产业的国际竞争力奠定了坚实的基础。

妊娠期糖尿病、孕期增重和喂养方式对其子代神经发育迟缓的影响

目的 探讨妊娠期糖尿病、孕期增重和喂养方式对其子代神经发育迟缓的影响。方法 采用回顾性队列研究,对纳入队列的8 023例产妇及其子代的基本信息进行描述性分析,在调整协变量后分析妊娠期糖尿病、孕期增重和喂养方式和其子代神经发育迟缓的关联。结果 研究对象妊娠年龄为(29.46±4.57)岁,孕前体质量指数(BMI)为(21.38±3.09)kg/m2。纳入子代中,男性4 450例(55.5%),采用母乳喂养4 351例(54.2%),出生时有735例(9.2%)为低体重新生儿。在校正了协变量后的logistic模型中,人工喂养与神经行为发育迟缓呈正相关[OR=1.70,95%CI:1.24~2.33]。在校正了协变量的多元线性回归模型中,妊娠期糖尿病、孕期增重不足,人工喂养与总发育商呈负相关(β=-0.44,95%CI:-0.87~-0.008;β=-0.73,95%CI:-1.25~-0.22;β=-0.80,95%CI:-1.34~-0.26)。母体妊娠糖尿病对其子代大运动和社交能力发育迟缓有明确影响(P <0.05);产妇增重不足对其子代五大能区的神经迟缓的影响均有统计学意义(P <0.05);人工喂养对其子代五大能区的神经迟缓有明确影响(P <0.05)。结论 产妇妊娠期增重不足以及采用人工喂养的方式是子代神经发育迟缓的危险因素,母体妊娠糖尿病是其子代大运动和社交能力发育迟缓的危险因素。

两种投喂模式对中华绒螯蟹生长性能及可食部位风味品质的影响

为研究不同投喂模式对中华绒螯蟹生长性能及可食部位风味品质的影响,设置全程投喂配合饲料(A)和前期投喂配合饲料+后期投喂冰鲜鱼(B)两种投喂模式开展养殖试验。每组设置3个重复,每个重复雄蟹和雌蟹各15只。养殖试验结束后测定生长性能,肌肉、肝胰腺和性腺相关品质指标以及肝胰腺和性腺的挥发性物质含量。结果表明:两种投喂模式对中华绒螯蟹肝胰腺指数、肥满度及附肢肌肉的硬度、内聚性、弹性、剪切力均无显著影响(P>0.05)。B组的雄蟹性腺指数以及雌蟹的增重率、特定生长率显著高于A组(P<0.05)。B组的雌蟹生长性能优于A组(P<0.05),同样地,B组雄蟹肝胰腺和性腺色泽、肌肉胶原蛋白含量也优于A组(P<0.05),且B组的中华绒螯蟹具有更好的风味(P<0.05)。综上所述,前期投喂配合饲料而后期投喂冰鲜鱼的饵料模式对中华绒螯蟹的育肥及风味品质具有更好的效果。因此,后续对于配合饲料的开发建议着重于呈味物质、促胶原蛋白生成和育肥功能饲料的开发方面。

干湿料饲喂方式下商品猪生产和健康指标模型构建与比较

【目的】精准饲养是当前生猪养殖产业的大趋势,但在实际应用中存在缺乏前期基础数据、各阶段湿料饲喂的采食量不明确等问题。本研究旨在探究干湿料饲喂猪只的生长发育规律、采食量动态模型和健康情况。【方法】选取132头平均初始体质量为(10.56±1.21)kg的商品猪,随机分为2组,每组11次重复,每次重复6头猪,2组分别饲喂干料和湿料,试验周期为120 d。通过Logistic、Gompertz和Von Bertalanffy 3种模型分析拟合干湿料饲喂猪只的生长曲线和采食量动态模型,并对干湿料饲喂猪只的健康情况进行研究。【结果】Von Bertalanffy模型拟合干料饲喂猪只生长曲线的效果最好,拟合度为0.999;Gomperz模型能更好地拟合湿料饲喂猪只的生长曲线,拟合度为0.999。Gomperz模型拟合干料饲喂猪只采食量模型的效果最好,拟合度为0.851;Von Bertalanffy模型能更好地拟合湿料饲喂猪只的采食量模型,拟合度为0.988。湿料饲喂保育仔猪的腹泻率和腹泻指数显著低于干料饲喂(P<0.05)。【结论】本研究构建了干湿料饲喂猪只的生长曲线和采食量模型,拟合效果较好;探明了干湿饲喂猪只的健康情况,为猪只的精准饲养提供了数据支撑。

“双循环”新发展格局下我国饲料进出口贸易的新机遇与新路径

饲料进出口贸易高速发展是促进我国国民经济发展的内生动力,也是加快推进农业强国建设进程的重大举措。“双循环”新发展格局视域下,我国饲料进出口贸易已取得初步成效,表现为出口贸易增速高于进口贸易、进口来源和出口市场更具广泛性、饲料产业发展更具规模化和精细化。在“双循环”新发展格局持续推动下,我国饲料进出口贸易需把握政策支持力度逐渐加大、产品供给能力不断增强、科技支撑作用逐步扩大的机遇,充分培育新优势、激发新动能。因此,文章提出建立健全配套政策,优化市场监管机制,打造创新科技平台,实现智慧化降本增效,拓宽国际贸易渠道,掌握饲料进口主动权等实践路径,以期为饲料进出口贸易发展提供可行性参考。

Light demand characteristics,production performance,and changes in the feeding patterns of broilers

Poultry is a light-sensitive animal and the light environment has an important influence on the growth and development of these animals.Previous studies have mainly focused on the effects of the light environment on various physiological indicators of poultry but seldom explored the light demand characteristics of broilers under free selection.This experiment mainly studied the light demand characteristics of broilers under a yellow LED light environment and the influence of different breeding densities[low-density(2.5 broilers/m^(2)),high-density(7.5 broilers/m^(2))]on the production performance and diet characteristics of broilers.Studies showed that the production performance indexes of low-density groups are higher than those of high-density groups.The feed and water consumption in the light area of the two experimental groups were significantly higher than those in the dark area,which means that the broilers showed a great preference for the light area.However,as the age of the broilers increased,the food and water consumption of the broilers decreased,indicating that broilers had a lower preference for light in the middle and late stages of growth.The statistical results for the residence frequency distribution characteristics showed that broiler chickens had different light requirements at different growth stages under the condition of active selection:1)low-density breeding environment:23.8L(light):0.2D(dark)for chicks and 22.3L:1.7D for adult broilers;2)high-density breeding environment:22.6L:1.4D for chicks and 15.0L:9.0D for adult broilers.This study will provide a reference for the optimization and control of light environment in broiler breeding.

杭州市常见园林植物对鸟类取食偏好的影响研究

为了解鸟类喜好取食的植物及其类型,揭示食源植物对鸟类取食行为的作用规律。以浙江农林大学东湖校区的常见食源植物和鸟类为研究对象,采用焦点观察法记录鸟类对食源植物的取食情况。结果表明:①共记录到37种鸟类,取食行为7398只次,有48种食源植物被鸟类取食;②吸引鸟类取食数量最多的是桂花(Osmanthus fragrans)、浙江柿(Diospyros japonica)、重阳木(Bischofia polycarpa)等,吸引鸟类物种数最多的为樟树(Cinnamomum camphora)、乌桕(Triadica sebifera)、桂花等。鸟类对核果、浆果等肉质果表现出明显偏好,而果实内部的种子可满足不同食性鸟类需求,叶、花对鸟类实际作用有限。不同鸟类在食物偏好上具有差异性,其中白头鹎(Pycnonotus sinensis)在食物选择上反映了广泛的食性和高度的适应性。此外,鸟类在选择食源植物时,主要受到其自身季节性行为动态的影响。其取食行为与食源植物的物候期一定程度上存在联系,根据食源植物的生长阶段和果实成熟度来选择取食时机。基于以上取食规律,建议园林植物配置选择桂花、浙江柿等核果、浆果类植物,同时辅以乌桕等提供种子食源的植物。为确保四季有食源,应依据植物物候期选择食源植物,增加樟树、冬青(Ilex chinensis)等冬季挂果期长的植物种植量。

不同饲养模式下宁蒗高原鸡源大肠杆菌耐药元件的分布特征

为了分析不同饲养模式下宁蒗高原鸡源大肠杆菌分离株中耐药基因、整合子和质粒型的分布特征,以便更好地保护和开发利用宁蒗高原鸡,试验采用PCR方法,在分离株系统分群的基础上,对耐药基因bla_(SHV)、bla_(TEM)、bla_(CTX-M-1)、bla_(CTX-M-2)、bla_(CTX-M-8/-25)、bla_(OXA-48)、tetA和tetB,整合子1和整合子2,10种质粒型进行了检测,并分析了不同质粒型间的关联性及系统分群、整合子、耐药基因、质粒型间的关联性。结果表明:B_(1)亚群的总检出率最高(68.21%),其次为B_(23)亚群(26.67%),不同饲养模式下不同亚群间的检出率存在差异;耐药基因bla_(TEM)的总检出率最高(81.54%),之后依次为bla_(OXA-48)(47.18%)、tetB(43.59%)和bla_(SHV)(42.05%),不同饲养模式下有些耐药基因的检出率存在差异;整合子1的总检出率(66.15%)高于整合子2(24.10%),笼养和混养模式下整合子1的检出率显著高于林下放养模式(P<0.05);质粒型IncI1的总检出率最高(97.44%),之后依次为IncP(82.05%)、IncN(63.59%)和IncFrep(56.41%)等,不同饲养模式下大部分质粒型的检出率存在差异;质粒型IncP、IncI1和IncN间,或这些质粒型与其他质粒型间具有高的关联性;整合子1与tetB、IncP和IncI1间有强关联性;IncP、IncFIB、IncI1、IncFrep、IncN与bla_(TEM)、tetB有关联性。说明不同饲养模式下,宁蒗高原鸡源大肠杆菌分离株中含有致病性分离株,且这些分离株携带不同的耐药基因、整合子和质粒型,在生产实践中需引起重视。

针织织造喂纱张力对精准图案成形的影响

经过前期研究,目前已经实现使用一根自固结子线织造出带有图案的针织物,该针织物图案立体感强,织造工艺简单。为了进一步探索图案成形的影响因素以及图案的修正方法,文章以织造时的喂纱张力为研究要点,分析张力变化时图案在针织物上的变化状态以及相对应精准纺纱工艺的调整方法。结果表明,用相同纺纱工艺纺制的自固结子线进行织造,当喂纱张力为0时,喂纱口纱线抖动严重,导致张力不稳定,图案产生无规律形变;当喂纱张力变大,喂纱口纱线保持张力稳定,但图案会发生规律性的向右倾斜。文章通过实验建立出图案修正公式,并根据修正公式调整线圈长度以及纺纱工艺参数,最终得到一次成形精准图案的针织物。

“双循环”新格局下饲料企业对外贸人才的实际需求及培养策略

随着“双循环”新格局的加速形成,饲料企业在国际贸易中的表现逐渐增强,并对种植业、畜牧养殖业的发展起到了积极的推动作用。与国内市场相比,全球饲料市场的竞争越发激烈。而企业之间的竞争归根到底是人才间的竞争,只有立足饲料企业对外贸人才的实际需求,持续打造高质量的饲料外贸人才队伍,才能提高饲料企业在国际市场中的竞争力,进而构建出饲料行业的“双循环”新发展格局。

社区婴幼儿贫血状况调查分析

目的调查分析社区婴幼儿贫血状况。方法选择某社区2022年9月至2023年9月进行儿童保健的婴幼儿8950例,均采血检测血常规指标,评估贫血检出情况,并分析喂养方式、母亲贫血状态、年龄等对贫血的影响,制定婴幼儿贫血干预对策。结果8950例婴幼儿贫血发生率为2.85%。在喂养方式方面,贫血组纯母乳喂养、及时添加辅食、添加动物性辅食贫血率均低于正常组,差异有统计学意义(P<0.05)。在母亲贫血状态方面,贫血组母亲孕期贫血、产后贫血率均高于正常组,差异有统计学意义(P<0.05)。贫血组1岁以下占比高于正常组,差异有统计学意义(P<0.05)。结论婴幼儿贫血与喂养方式、母亲贫血状态、年龄等均密切相关。社区在开展儿童保健工作时,应根据以上因素给予针对性指导。

牦牛犊牛体内矿物质元素钙、磷、钠、钾、镁沉积分布规律

试验旨在探究40~90 kg牦牛犊牛体内主要常量矿物质元素分布规律。选取35头体重(46.40±6.50)kg、日龄(60±3)d、健康的牦牛公犊牛为试验动物,随机等分为5组,即起始屠宰组(BL),中期屠宰组(M),终末期屠宰的高饲喂组(自由采食,AL组)、中饲喂组(70%自由采食,IR70)和低饲喂组(40%自由采食,IR40)。试验各组犊牛按不同生长阶段饲喂一定量代乳粉,同时自由采食苜蓿干草和开食料;高饲喂组、中饲喂组和低饲喂组犊牛在同期饲喂等量代乳粉基础上,分别按自由采食、70%采食量、40%采食量补充饲喂苜蓿干草和开食料,精粗比均为3∶7。根据试验不同时间点每组随机选取5头牦牛进行屠宰采样,测定体内各组织中的主要常量矿物质含量,分析获得钙、磷、钠、钾、镁在牦牛犊牛体内沉积分布规律。结果表明:(1)内脏(含血液)、脂肪组织中的干物质含量随体重增加而增加,且AL、IR70组和IR40组均高于M组和BL组。(2)钙主要分布在骨骼(98.14%);磷也主要分布在骨骼(86.19%),在肉和内脏(含血液)中有少量分布;钠元素35.69%分布在骨骼中,18.39%分布在牛皮,17.81%分布在内脏(含血),16.22%分布在肉中,其余少量的钠分布于脂肪和毛中;钾在肉中分布量最大,为41.65%,在内脏(含血液)中的含量为36.41%,牛毛(8.21%)、牛皮(6.04%)和骨骼(5.26%)中钾含量也较为丰富,在脂肪中的含量(2.43%)较少;72.81%的镁分布在骨骼中,在肉中的含量为13.76%,在内脏(含血液)和牛毛中含量相近,剩余少量分布在牛皮和脂肪中。综上得出,牦牛犊牛体内主要常量矿物质元素沉积量随体重和饲喂量增加而增加;钙、磷、钠、镁主要分布于骨骼中,钾主要分布于肉中,在软组织和牛毛中含量也较为丰富;各主要常量矿物质元素在脂肪中分布均匀,且含量较少。