THERMAL COMFORT OF DAIRY COWS IN BARN WITH OPEN-SIDED CONSTRUCTION

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rancid milk 酸败牛奶，发乳desiccanted milk 奶粉lapper milk 酸牛奶，凝乳，乳凝块low fat milk 低脂牛奶raw milk 生奶，生牛奶，未经消毒的牛奶，原料乳（奶），生鲜奶，未消毒奶finished milk (杀菌毕待装瓶的)成品奶Schloss milk 类人乳colostrum 初乳colostral milk 初乳residual milk 残留奶chocolate milk 巧克力牛奶teparized milk 四角纸包装无菌灌装的超高温杀菌牛奶whole milk 完全乳，全脂粉，全脂牛奶，全脂奶，全脂牛奶，全乳fluid milk 液态奶accredited milk 特级牛奶standardized milk 标准乳，标准化牛奶，脂肪含量标准化(牛)乳long milk 粘丝状乳(一种变质现象)tainted milk 污染乳，异味乳school milk (英国)学校膳食用乳toned milk 调配牛奶Frosonic milk 超声波冰冻乳pigeon's milk 不存在的事物normal milk (分娩一星期后的)正常牛乳baby milk 婴儿奶粉acid milk 酸乳casein milk 干酪素乳液ewe's milk 绵羊奶cheese milk (制)干酪用乳irradiated milk 紫外线照射牛奶，经(紫外线)照射的乳uperized milk 直接蒸汽喷射杀菌的牛奶recombined milk 重配牛奶，调制奶defatted milk 脱脂牛奶sweet milk 甜牛奶nonfat dry milk 脱脂奶粉fluid milk 液态奶genuine milk 真乳，真(牛)乳，非人造乳ice milk 冻牛乳unpasteurized milk 未经巴氏杀菌的奶Caucasian milk 高加索酸牛奶(凝乳)concentrated milk 浓缩奶，炼乳abnormal milk 异常乳maternized milk 母乳化牛奶synthetic milk 人造奶fortified milk 营养牛奶，强化牛乳(增加维生素与矿物质的牛乳) humanized milk 人奶化牛奶，母乳化的牛乳goat milk 山羊乳，羊奶dried milk 全脂奶粉almond milk 杏仁乳pure milk 纯牛奶soybean milk 豆浆，豆奶，豆桨zero milk 用无机氮盐喂牛所得的奶designated milk 专业用牛奶glacial milk 冰川乳浆milk cow 乳牛，奶牛milk house牛奶房，牛奶场milk veal小牛肉，授乳犊牛，小乳牛milk sheep乳用羊milk gland 乳腺lactation 哺乳期milk industry乳业milk clarifier净乳机milk-pump吸奶器milk boiler奶煲milk pan 奶锅milk heater 牛奶加温器，牛奶加温器牛奶杀菌器milk walk 牛奶递送区，牛奶递送区域milk float 送牛奶之马车milk bath 乳浴milk cure乳疗法，乳食疗法milk test 乳汁检验，乳试验，乳汁检验milk scale 乳量计，乳白度milk recording乳量记录milk meter量乳计,牛奶(流)量计milk density 乳比重milk gauge牛奶比重表milk texture牛奶组织，牛奶质地milk-toast无味道的，软弱的，不振作的，软弱无力的milk-white 乳白色的，乳白的milk glass 乳色玻璃，乳白玻璃milk spots 乳状斑，乳色斑，乳斑，军人斑Whey 乳清Lactose 乳糖Peptide 缩氨酸milk precursor 乳前体物milk albumin 乳清蛋白milk acid乳酸milk-globule乳球Colostrum Breakup Protein初乳分离蛋白粉Alginate 海藻酸locust bean Guar刺槐豆胶carrageenan 卡拉胶，鹿角菜胶，角叉菜胶carboxymethyl cellulose CM－纤维素，羧甲基纤维素fruit preparation 水果配料milk crumb可可、奶粉和糖混合制成的颗粒milk fermentation乳发酵starter culture发酵剂single-strain单株发酵剂multi-strain多株发酵剂mixed-strain 混合发酵剂direct-vat type cultures直投式发酵剂bulk-starter 批量发酵剂milk coagulant 凝乳剂milk curdling 乳的凝结UHT(ultra heat treated) 超热处理freeze-dried or lyophilized冻干frozen-concentrated冷冻浓缩milk powder 奶粉full cream milk powder 全脂奶粉whole milk powder 全脂奶粉coconut milk powder 椰奶粉instant coconut milk powder 速溶椰汁粉pressure spray milk powder 压力喷雾干燥奶粉modified milk powder 改性牛奶粉instant nonfat milk powder 速溶脱脂奶粉long life milk powder 保久奶粉milk powder candy 奶片milk powder cake 奶粉压片feed butter milk powder 饲料用酪乳粉skim milk powder 脱脂奶粉instant milk powder 速溶奶粉milk powder manufacture 奶粉生产[制造]milk powder hopper 奶粉包装用漏斗milk powder machine 制奶粉机manufacturing machine of milk powder 奶粉制造机milk powder collector 奶粉收集器milk powder plant 奶粉工厂yoghurt or yogurt酸奶acidophilus milk嗜酸菌酸奶Set-style Yogurt 凝固型酸奶Stirred style yogurt 搅拌型酸奶Bulgarian buttermilk 保加利亚酪乳cultured buttermilk发酵酪乳cheese 干酪Cheddar cheese 切达干酪Swiss cheese瑞士干酪Kefir 克菲尔Koumiss马奶酒Emmental cheese埃门塔尔干酪Cottage cheese农家干酪sour cream 酸奶油ripened cream butter成熟黄油milk brittle 脆心牛奶糖creamy candy, milk candy, creamy candy, milk candy toffee 奶糖dairy cow 乳牛，奶牛dairy temperament 乳用气质dairy herd 乳牛群，乳畜群dairy maid 奶场女工dairy man 奶场场主，养牛工dairy farmer 奶农rotary dairy 圆形自转挤奶台dairy bull 乳用品种公牛dairy pasture 乳牛用草地dairy products 乳制品，奶产品，奶制品dairy farmer 奶农dairy product 乳制品，奶产品dairy husbandry 制酪业，乳牛业，乳牛场，牧场dairy food 乳(制)品dairy industry 乳业dairy farm 乳牛场，奶场，奶牛场dairy farming 乳牛养殖dairy performance 产乳性能dairy barn 挤奶站,挤奶厅dairy science 乳牛学dairy equipment 乳品加工设备，奶品加工设备dairy stock 乳牛，奶牛，奶牛，奶畜，奶场(中的)牛羊dairy bacterium 乳品细菌dairy manure 牛粪dairy quality 泌乳特性dairy salt 乳制品加工用(食)盐dairy house 乳品贮藏室dairy microorganism 乳品微生物dairy goat 乳用羊dairy cattle 乳牛，奶牛，奶牛，乳牛dairy cattle 乳畜dairy plant 乳品厂，乳品加工厂dairy produce 乳制品dairy breed 乳用品种dairy feed 乳牛饲料，乳质饲料dairy utensil 挤奶器dairy corral 奶牛畜栏dairy character 产乳性能dairy bacteriology 乳业细菌学，乳品细菌学dairy industry 乳业，乳品加工业dairy-bred 乳用种的dairy processing 乳品加工dairy beef 肉用乳牛dairy farming 制酪业，乳牛业，乳品业，酪农业dairy machinery 制酪机dairy hygiene 乳品卫生milk cow/dairy cow 奶牛corral-type dairy 围栏式乳牛场dairy heifer replacement 后备乳用小母牛Dairy Science Abstracts (英) 乳业文摘dairy cattle husbandry 乳牛业Dairy Improvement Association 乳牛改良协会dairy barn scoop 奶牛棚用铲斗International Dairy Federation 国际乳业联盟quirement of dairy cattle 乳牛养分需要量dairy by-product 乳副产品Dairy Improvement Registry 乳牛改良登记制dairy cattle field 奶牛场Journal of Dairy Science (美) 乳业学报Journal of Dairy Research (英) 乳业研究学报character of different dairy cattle 各种奶牛的特点nutrients requirement of dairy cattle 乳牛养分需要量body parts of a dairy cow 乳用母牛躯身的部位National Dairy Research Institude (印度) 国立乳业研究所technique treating morbid sterility of dairy cattle with laser needle 激光针治疗乳牛疾病性不孕Infant formula 婴儿配方乳粉milk collection 收奶hand milking 人工挤奶galactagogue 催奶剂噬菌体，bacteriophage国际细菌命名法规，the International Code of Nomenclature of Bacteria嗜热链球菌，Streptococcus thermophilus两歧双歧杆菌，Bifidobacterium bifidum短双歧杆菌，Bifidobacterium breve长双歧杆菌，Bifidobacterium longum类肠膜明串珠菌，Leuconostoc paramesenteroides戊糖片球菌，Pediococcus pentosaceus嗜酸乳杆菌，Lactobacillus acidophilus脆弱克鲁维酵母，Kluyveromyces fragilis乳酸克鲁维酵母，Kluyveromyces lactis保加利亚乳杆菌，Lactobacillus bulgaricus干酪乳杆菌，Lactobacillus casei干酪乳杆菌鼠李糖亚种，Lactobacillus casei subsp. rhamnosus高加索乳杆菌，Lactobacillus caucasicus德氏乳杆菌，Lactobacillus delbrueckii约古特乳杆菌，Lactobacillus jugurti乳酸乳杆菌，Lactobacillus lactis赖氏乳杆菌，Lactobacillus leichmanii柠胶明串珠菌，Leuconostoc citrovorum乳脂明串珠菌，Leuconostoc cremoris葡聚糖明串珠菌，Leuconostoc dextranicum谢氏丙酸杆菌，Propionibacterium shermanii粪链球菌，Streptococcus faecalis乳脂链球菌，Streptococcus cremoris乳酸链球菌乳脂亚种，Streptococcus lactis subsp. cremoris双乙酰乳酸链球菌，Streptococcus diacetylactis乳酸链球菌双乙酰乳酸亚种，Streptococcus lactis subsp. diacetylactis乳酸链球菌乳酸亚种，Streptococcus lactis subsp. lactis唾液链球菌嗜热亚种，Streptococcus salivarius subsp. thermophilus新名称：马克思克鲁维酵母马克思生物突变株，Kluyveromyces marxianus biovar. marxianus马克思克鲁维酵母乳酸生物突变株，Kluyveromyces marxianus biovar. lactis 德氏乳杆菌保加利亚亚种，Lactobacillus delbrueckii subsp. bulgaricus干酪乳杆菌干酪亚种，Lactobacillus casei subsp. casei鼠李糖乳杆菌，Lactobacillus rhamnosus克菲尔乳杆菌，Lactobacillus kefir德氏乳杆菌德氏亚种，Lactobacillus delbrueckii subsp. delbrueckii瑞士乳杆菌约古特亚种，Lactobacillus helveticus subsp. jugurti德氏乳杆菌乳酸亚种，Lactobacillus delbrueckii subsp. lactis德氏乳杆菌赖氏亚种，Lactobacillus delbrueckii subsp. leichmanii肠膜明串珠菌乳脂亚种，Leuconostoc mesenteroides subsp. cremoris肠膜明串珠菌葡聚糖亚种，Leuconostoc mesenteroides subsp. dextrancium 弗氏丙酸杆菌谢氏亚种，Propionibacterium freudenreichii subsp. shermanii 粪肠球菌，Enterococcus faecalis乳酸乳球菌乳脂亚种，Lactococcus lactis subsp. cremoris乳酸乳球菌乳酸亚种（双乙酰生物突变株），Lactococcus lactis subsp. lactis (biovar. diacetylactis)乳酸乳球菌乳酸亚种，Lactococcus lactis subsp. lactis。

Thermal comfort in naturally ventilated buildings

eScholarship provides open access, scholarly publishing services to the University of California and delivers a dynamicresearch platform to scholars worldwide.Center for the Built EnvironmentUC BerkeleyPeer ReviewedTitle:Thermal comfort in naturally ventilated buildings: revisions to ASHRAE Standard 55Author:de Dear, Richard Brager, Gail Publication Date:02-01-2002Series:Envelope SystemsPermalink:https:///uc/item/2pn696vvKeywords:thermal comfort, adaptive model, standard, energy conservation, natural ventilation, field studies Abstract:Recently accepted revisions to ASHRAE Standard 55—thermal environmental conditions for human occupancy, include a new adaptive comfort standard (ACS) that allows warmer indoor temperatures for naturally ventilated buildings during summer and in warmer climate zones. The ACS is based on the analysis of 21,000 sets of raw data compiled from field studies in 160 buildings located on four continents in varied climatic zones. This paper summarizes this earlier adaptive comfort research, presents some of its findings for naturally ventilated buildings, and discusses the process of getting the ACS incorporated into Standard 55. We suggest ways the ACS could be used for the design, operation, or evaluation of buildings, and for research applications. We also use GIS mapping techniques to examine the energy-savings potential of the ACS on a regional scale across the US. Finally, we discuss related new directions for researchers and practitioners involved in the design of buildings and their environmental control systems.Copyright Information:Copyright 2002 by the article author(s). This work is made available under the terms of the Creative Commons Attribution 4.0 license, /licenses/by/4.0/Thermal comfort in naturally ventilated buildings:revisions to ASHRAE Standard 55Richard J.de Dear a,*,Gail S.Brager baDivision of Environmental and Life Sciences,Macquarie University,Sydney,NSW 2109,Australia bCenter for Environmental Design Research,University of California,Berkeley,CA 94720-1839,USAAbstractRecently accepted revisions to ASHRAE Standard 55—thermal environmental conditions for human occupancy,include a new adaptive comfort standard (ACS)that allows warmer indoor temperatures for naturally ventilated buildings during summer and in warmer climate zones.The ACS is based on the analysis of 21,000sets of raw data compiled from ﬁeld studies in 160buildings located on four continents in varied climatic zones.This paper summarizes this earlier adaptive comfort research,presents some of its ﬁndings for naturally ventilated buildings,and discusses the process of getting the ACS incorporated into Standard 55.We suggest ways the ACS could be used for the design,operation,or evaluation of buildings,and for research applications.We also use GIS mapping techniques to examine the energy-savings potential of the ACS on a regional scale across the US.Finally,we discuss related new directions for researchers and practitioners involved in the design of buildings and their environmental control systems.#2002Published by Elsevier Science B.V .Keywords:Thermal comfort;Adaptive model;Field studies;Natural ventilation;Energy conservation;Standard1.IntroductionThe purpose of ASHRAE Standard 55—thermal environ-mental conditions for human occupancy,is ‘‘to specify the combinations of indoor space environment and personal factors that will produce thermal environmental conditions acceptable to 80%or more of the occupants within a space’’[1].While ‘‘acceptability’’is never precisely deﬁned by the standard,it is commonly agreed within the thermal comfort research community that ‘‘acceptable’’is synonymous with ‘‘satisfaction’’,and that ‘‘satisfaction’’is associated with thermal sensations of ‘‘slightly warm’’,‘‘neutral’’,and ‘‘slightly cool’’.‘‘Thermal sensation’’is the question most commonly asked in both laboratory and ﬁeld studies of thermal comfort.What,then,inﬂuences peoples’thermal sensations?ASH-RAE Standard 55is currently based on the heat balance model of the human body,which assumes that thermal sensation is exclusively inﬂuenced by four environmental factors (temperature,thermal radiation,humidity and air speed),and two personal factors (activity and clothing).An alternative (and,we believe,complementary)theory of thermal perception is the adaptive model,which states that factors beyond fundamental physics and physiology play animportant role in building occupants’expectations and thermal preferences.Thermal sensations,satisfaction,and acceptability are all inﬂuenced by the match between one’s expectations about the indoor climate in a particular context,and what actually exists [2].While the heat balance model is able to account for some degrees of behavioral adaptation such as changing one’s clothing or adjusting local air velocity,it ignores the psychological dimension of adapta-tion,which may be particularly important in contexts where people’s interactions with the environment (i.e.personal thermal control),or diverse thermal experiences,may alter their expectations,and thus,their thermal sensation and satisfaction.One context where these factors play a parti-cularly important role is naturally ventilated buildings—the focus of this paper.Happily,we are seeing an increasing number of architects and engineers paying attention to the plea from occupants for operable windows in non-residential buildings.Unfortu-nately,they have often been limited in their ﬂexibility to pursue such options because of the relatively narrow range of interior thermal conditions allowed under earlier versions of ASHRAE Standard 55.These conditions have been assumed to be universally applicable across all building types,climates,and populations.Although,it was never intended for ASHRAE Standard 55to require air-condition-ing for buildings,it has been very difﬁcult to meet the standard’s narrow deﬁnition of thermal comfortwithoutEnergy and Buildings 34(2002)549–561*Corresponding author.Tel.:þ61-2-9850-7582;fax:þ61-2-9850-8420.E-mail address:rdedear@.au (R.J.de Dear).0378-7788/02/$–see front matter #2002Published by Elsevier Science B.V .PII:S 0378-7788(02)00005-1such mechanical assistance,even in relatively mild climatic zones.Needless to say the energy costs of providing this constant supply of uniformly conditioned,cool,still and dry air are signiﬁcant,as are the well-known environmental consequences associated with this vast energy end-use. How can thermal comfort standards play a role in facil-itating the appropriate use of energy-efﬁcient,climate-responsive building design strategies?Theﬁrst step must be to recognize that comfort depends on context.People living year-round in air-conditioned spaces are quite likely to develop high expectations for homogeneity and cool temperatures,and may become quite critical if thermal conditions in their buildings deviate from the center of the comfort zone they have come to expect.In contrast, people who live or work in naturally ventilated buildings where they are able to open windows,become used to thermal diversity that reﬂects local patterns of daily and seasonal climate variability.Their thermal perceptions—both preferences as well as tolerances—are likely to extend over a wider range of temperatures than are currently reﬂected in the old ASHRAE Standard55comfort zone. As an organization representing and furthering the inter-ests of the air-conditioning industry ASHRAE must be commended for acknowledging these subtle issues sur-rounding thermal perception.ASHRAE recently funded research to quantify the difference between peoples’thermal responses in air-conditioned and naturally ventilated build-ings.The outcome was a proposal for a new adaptive comfort standard to complement the traditional PMV-based comfort zone.This paper brieﬂy describes and expands on the results of that project,ASHRAE RP-884:developing an adaptive model of thermal comfort and preference,and describes how the work was recently incorporated into ASHRAE Standard55,and how both practitioners and researcher might apply the ACS.For greater detail about the background research,previous papers describe the results of our literature search on thermal adaptation[3], the speciﬁc procedures for developing the database[4],and our analysis methods andﬁndings[5,6].2.Methods:developing the ASHRAE RP-884database In the mid-1980s,ASHRAE began funding a series of ﬁeld studies of thermal comfort in ofﬁce buildings spread across four different climate zones.They were speciﬁcally designed to follow a standardized protocol developed during theﬁrst in the series,ASHRAE RP-462[7].Since that time numerous other thermal comfort researchers independently adopted the same procedures for collecting both physical and subjective thermal comfort data in their ownﬁeld studies.In1995,ASHRAE RP-884began by collecting rawﬁeld data from various projects around the world that had followed this standardized(or a similar)protocol,and/or where the data met strict requirements regarding measurement techniques,type of data collected,and database structure.Standardized data processing techniques,such as methods for calculating clo and various comfort indices,were then applied consistently across the entire database[4].This enabled RP-884to assemble a vast,high-quality,internally consistent database of thermal comfortﬁeld studies.The RP-884database contains approximately21,000sets of raw data from160different ofﬁce buildings located on four conti-nents,and covering a broad spectrum of climate zones.The locations selected for the database and depicted in Fig.1 include Bangkok,Indonesia,Singapore,Athens,Michigan, several locations each in California,England,and Wales,six cities in Australia(Darwin,Townsville,Brisbane,Sydney, Melbourne,Kalgoorlie)andﬁve cities in Pakistan(Karachi, Quettar,Multan,Peshawa,Saidu).The data includes a full range of thermal questionnaire responses,clothing and metabolic estimates,concurrent indoor climate measure-ments,a variety of calculated thermal indices,and concur-rent outdoor meteorological observations.The buildings in the database were separated into those that had centrally-controlled heating,ventilating,and air-conditioning systems(HVAC),and naturally ventilated buildings(NV).Since the RP-884database comprises exist-ingﬁeld experiments,this classiﬁcation came largely from the originalﬁeld researchers’descriptions of their buildings and their environmental control systems.The primary dis-tinction between the building types was that the NV build-ings had no mechanical air-conditioning,and the natural ventilation occurred through operable windows that were directly controlled by the occupants.In contrast,occupants of the HVAC buildings had little or no control over their immediate thermal environment.Since most of the NV buildings were studied in the summer,in most cases,the type of heating system was irrelevant.The few that were studied in winter may have had a heating system in opera-tion,but it was of the type that permitted occupant control. Unfortunately,there were not enough hybrid ventilation (also called‘‘mixed-mode’’)buildings in the RP-884data-base to allow their separate analysis.All statistical analyses were performed separately for the HV AC and NV buildings, using each individual building as the initial unit of analysis, and then conducting a meta-analysis of the separate statis-tical calculations done within each building.(see[5]for details of analyses).As noted earlier,the environmental inputs to conventional heat-balance thermal comfort models(e.g.PMV)are all taken from the indoor environment immediately surround-ing the building occupants.These models also require the user to have knowledge of the building occupants’clothing insulation and metabolic rates,which are often difﬁcult to estimate in theﬁeld.But adaptive comfort models do things differently in that they use an outdoor thermal environmental variable as their input.Since presenting the early versions of our adaptive models to the engineering and comfort research community in1998,we have often been asked to explain the relevance of outdoor temperature to the prediction of the temperature that people willﬁnd comfortable indoors.The550R.J.de Dear,G.S.Brager/Energy and Buildings34(2002)549–561question goes to the fundamental difference of approach between heat-balance and adaptive models of thermal com-fort.The former account for thermal comfort in terms of the microclimate immediately affecting the energy exchanges (i.e.heat balance)of the subject,whereas adaptive models predict comfort from broad-scale,contextual factors.But why outdoor climate?First,we believe that weather and seasons exert a pervasive in ﬂuence on our behavioral adaptations to the thermal environment.For example,we typically use information about expected maximum daily temperatures along with recent experiences when making decisions about what to wear on a particular day.Secondly,we think weather,both recent past and predicted near-future,along with longer-term seasonal swings deter-mines our psychological adaptations in the form of thermal expectations.But the matter of how to best characterize outdoor climate remains an interesting question in the comfort research community.One might presume daily outdoor temperatures to be a more appropriate time-scale for use in predicting adaptive thermal comfort temperatures than monthly averages.Our choice of the latter was made on purely pragmatic grounds.Months represent the temporal scale most commonly adopted by national weather bureaux for collection and presentation of climatological normals.Since these form the basis of most engineering calculations they are obviously more appropriate to an engineering standard such as ASHRAE Standard 55than some shorter time-scale,despite the loss of resolution.As is often,the case when making the transition from the researcher ’s world to that ofthe practitioner,certain sacri ﬁces in precision are necessary in order to make models simple and useful to as many people as possible.Failure to make the sacri ﬁce usually renders the results of research of academic interest only —a fate suffered by more than one thermal comfort model to date.3.Results:thermal comfort in naturally ventilated buildingsFig.2a and b shows some of the most compelling ﬁndings from our separate analysis of HVAC and NV buildings,in the upper and lower panels,respectively.We believe that the clear differences in these patterns also vindicate our building classi ﬁcation scheme.The graphs present a regression of indoor comfort temperature 1for each building against mean outdoor air temperature recorded for the duration of the building study in question.Regressions were based only on buildings that reached statistical signi ﬁcance (P ¼0:05)in the derivation of their own neutral or preferred temperature.As a result,20buildings in the RP-884database had tobeFig.1.The geographic distribution of building studies comprising the RP-884thermal comfort database that formed the basis of the adaptive model and adaptive comfort standard in this paper (map adapted from Rudloff [8]).1For this analysis,‘‘preference ’’was considered as a more appropriate indicator of optimum thermal conditions than the traditional assumption of ‘‘neutral thermal sensation ’’.In the HV AC buildings,preferred temperature was slightly warmer than neutral temperatures in cooler climates,and slightly cooler in warmer climates (by up to 18C at either extreme end).There was no difference in the NV buildings.The indoor comfort temperature on the y -axis,therefore,includes a semantic correction factor to modify estimates of neutral temperatures in HV AC buildings to more accurately reflect preference.R.J.de Dear,G.S.Brager /Energy and Buildings 34(2002)549–561551eliminated from this analysis because of their small sample sizes or very homogeneous indoor e of the 20cases would have necessitated certain assumptions about thermal sensitivities of their occupants that were unsustain-able on the empirical evidence at hand.Each graph in Fig.2a and b,shows two regressions,one based on observed responses in the RP-884database,and the other on predic-tions using Fanger ’s PMV [9].The latter take into account clo,metabolic rate,air speed and humidity averaged within the building in question.The original data points through which the adaptive model regression line was ﬁtted are also shown,but it should be noted that this is a weighted regression so that outliers representing small sample sizes had a relatively smaller effect on the slope of the model.Two strong patterns emerge from these graphs.First,the steeper gradient of observed responses in NV buildings (Fig.2b)compared to HV AC buildings (Fig.2a)suggests that occupants of HV AC buildings become more ﬁnely adapted to the narrow,constant conditions typically provided by mechanical conditioning,while occupants of NV build-ings prefer a wider range of conditions that more closely re ﬂect outdoor climate patterns.Secondly,a comparison of the observed (ﬁtted to OBS)and predicted lines within each graph clari ﬁes the role of adaptation in these two building types.In the HV AC build-ings,PMV was remarkably successful at predicting comfort temperatures,demonstrating that behavioral adjustments of clothing insulation and room air speeds (both of which are inputs to the PMV model)fully explained the relationship between indoor comfort temperature and outdoor climatic variation.In this sense,the PMV could be considered a partially-adaptive model.In contrast,in the NV buildings (Fig.2b),the difference between these PMV-based predic-tions and the adaptive model (ﬁtted to OBS)shows that such behavioral adjustments accounted for only half of the climatic dependence of comfort temperatures.Excluding gross and systematic measurement error for the time being,the unexplained residual must come from in ﬂuencesnotFig.2.(a)Observed (OBS)and predicted indoor comfort temperatures from RP-884database,for HV AC buildings.Note that the observed comfort temperatures have been corrected for the effects of semantics (see Brager and de Dear [3]).The adaptive model fitted by weighted regression to observed comfort temperatures has an R 2¼53%(P ¼0:0001).(b)Observed (OBS)and predicted indoor comfort temperatures from RP-884database,for naturally ventilated buildings.The adaptive model fitted by weighted regression to observed comfort temperatures has an R 2¼70%(P ¼0:0001).552R.J.de Dear,G.S.Brager /Energy and Buildings 34(2002)549–561accounted for by the PMV model,and our analysis suggests that psychological adaptation is a likely explanation.In particular,we hypothesize that indoor comfort temperatures in NV buildings are strongly inﬂuenced by shifting thermal expectations resulting from a combination of higher levels of perceived control,and a greater diversity of thermal experi-ences in such buildings.Our hypothesis about‘‘expectations’’underlying the dis-crepancy between the predictions of the laboratory-based PMV model and the comfort temperatures actually observed in naturally ventilated buildings has not been allowed to pass without comment at various conferences where it has been aired.For example,it has been suggested elsewhere in this special issue of‘‘Energy and Buildings’’that the discre-pancy in warm climateﬁeld studies can be accounted for by systematic errors in the estimation of metabolic rates[10].It was claimed that if estimated metabolic rate is reduced by an average of10%,then PMV predictions would match observed thermal sensation much more closely.However, to us this seems to underestimate the magnitude of the discrepancy by a factor of two.For example,using the ‘‘WinComf’’software[11]funded by ASHRAE TC2.1, we input the following average indoor climatic conditions, representative of measurements made in a typical tropical building in the RP-884database,and found to be comfor-table by the adaptive model in Fig.2b:temperatures,t a¼t r¼26:78C;air speed,v¼0:25m/s;humidity,RH¼50%;clothing insulation,I cl¼0:5clo;metabolic rate,M¼1:3.These inputs generated a PMV¼þ0:5,whereas the adaptive model in Fig.2b indicates these conditions would be optimal(preferred and neutral).The metabolic rate would need to reduce from1.3to1.05met units in order to bring PMV back to neutral(0)and that represents a20%reduction in met rate.In short,these subjects would need to be performing their‘‘light ofﬁce duties’’with unrealistic efﬁ-ciency of energy in order to explain away the1.78C dis-crepancy between the adaptive model’s comfort temperature and the counterpart predicted PMV.Raising further doubt about the suggestion that over-estimation of metabolic rate explains the discrepancy in Fig.2b is the necessity for the overestimation to be a problem exclusively found in the tropics or other hotﬁeld study locations.Since some of tropical data in the RP-884 adaptive model database were actually collected by researchers withﬁeld study experience from the mid-lati-tudes(and in some cases,their mid-latitude data included in the RP-884database),there seems to be little prospect of a procedural or instrumental explanation for selective over-estimation in metabolic rates.Fanger and Toftum’s[10] suggestion of a‘‘siesta factor’’explaining lower metabolic rates in warm climates is perhaps reminiscent of Ellsworth Huntington’s ethnocentric spin on climatic determinism in ‘‘Mainsprings of Civilization’’[12],long since discredited in the social and environmental sciences.And what about the discrepancy in milder climates to the left-hand side of Fig.2b?The logical extension of Fanger and Toftum’s ‘‘siesta factor’’hypothesis is that ofﬁce workers in cooler locations must expend approximately1.6met units to match predicted and observed thermal sensation,essentially for the same type of work activities that an ofﬁce worker in the tropics would have to expend1.05met units on to enable a match.In short,the metabolic‘‘siesta’’hypothesis does not withstand close scrutiny.The adaptive modelﬁndings depicted in Fig.2b led to a proposal for an ACS that would serve as an alternative to the PMV-based method in ASHRAE Standard55for naturally ventilated buildings.The outdoor climatic environment for each building was characterized in terms of mean outdoor dry bulb temperature T a,out,instead of the ETÃindex that was originally proposed in theﬁrst publication of the ACS[5]. The reason for the downgrade to a simpler outdoor tem-perature expression is that the theoretically more adequate thermal indices such as ETÃrequire both specialized soft-ware and expertise that most practicing HV AC engineers are unlikely to possess.Optimum comfort temperature,T comf, was then similar to the regression shown in Fig.2b,but re-calculated based on mean T a,out:T comf¼0:31T a;outþ17:8(1) The next step was to deﬁne a range of temperatures around T comf corresponding with90and80%thermal acceptability.Only,a small subset of the studies in the RP-884database had included direct assessments of thermal acceptability,and the analysis of these data was not statis-tically signiﬁcant.We were,therefore,left with having to infer‘‘acceptability’’from the thermal sensation votes,and started with the widely used relationship between group mean thermal sensation vote and thermal dissatisfaction(i.e. the classic PMV–PPD).The PMV–PPD relationship indi-cates that a large group of subjects expressing mean thermal sensation vote ofÆ0.5(orÆ0.85)could expect to have10% (or20%)of its members voting outside the central three categories of the thermal sensation scale(assumed to repre-sent dissatisfaction).Applying theÆ0.5andÆ0.85criteria to each building’s regression model of thermal sensation as a function of indoor operative temperature produced a90and 80%acceptable comfort zone,respectively,for each build-ing.Arithmetically,averaging those comfort zone widths across all the NV buildings produced a mean comfort zone band of58C for90%acceptability,and78C for80% acceptability,both centered on the optimum comfort tem-perature.We then applied these mean values as constant temperature ranges around the empirically-derived optimum temperature(T comf)in Eq.(1).The resulting90and80% acceptability limits are shown in Fig.3.Oftentimes when this ACS graph has been presented in conferences and other scientiﬁc forums we have been asked to justify the constant widths for the80and90%R.J.de Dear,G.S.Brager/Energy and Buildings34(2002)549–561553acceptability limits.Some commentators have hypothesized that the acceptability ranges should show some relationship with outdoor temperature.To test this hypothesis,we extracted the regression gradient terms for the thermal sensation versus indoor operative temperature models for each of the buildings that were included in Fig.2b.We chose thermal sensation regression model coef ﬁcients because this was the parameter used to directly calculate the original 80and 90%acceptability limits depicted in the ACS (Fig.3).These coef ﬁcients were then plotted against the mean out-door temperatures prevailing at the time of each building ’s comfort ﬁeld study.The results are shown in Fig.4and it is clear that there is no climate-dependency for indoor thermal sensitivity,and we take this as supporting the standardiza-tion of acceptability limits across the entire range of outdoor climates,as represented in Fig.3.Note that Fig.3is slightly different than the one originally produced by RP-884[5],but closely resembles the one included in the recently revised ASHRAE Standard 55.The decisions made to modify the original graph are described in more detail later in this paper.But before describing the process of getting Fig.3incorporated into ASHRAE Standard 55,it may be useful to look in more detail at the NV buildings that were included in ouranalysis.Fig.3.Proposed adaptive comfort standard (ACS)for ASHRAE Standard 55,applicable for naturally ventilatedbuildings.Fig.4.The effects of outdoor climate on the indoor thermal sensation regression models for naturally ventilated buildings.Only regression coefficients meeting P <0:05significance were included in the analysis.The sensitivity of indoor thermal sensations to changes in indoor temperature (y -axis)shows no relationship to outdoor climate (x -axis),thereby supporting constant 80and 90%thermal acceptability bands across the full range of climates represented in the ACS (Fig.3).554R.J.de Dear,G.S.Brager /Energy and Buildings 34(2002)549–561Fig.5a and b shows the operative temperatures and thermal sensations from each of the NV buildings in the RP-884database,2as a function of the mean outdoor air temperature that existed during a continuous part of each study that took place in a given month or season.For each line,the dot represents the mean of the measurements,and the lower and upper bands represent the 20th and 80th percentiles,respec-tively.Fig.5a also shows the 80%limit of the ACS model for comparison.Note that most thermal sensation votes in the database were recorded as integer numbers,and so the percentile bars tend to fall on integer numbers as well.We chose to present the 20th and 80th percentiles because they would more accurately reveal any asymmetries around the mean,as compared to using the more traditional þone standard deviation.A couple of clear patterns are seen in Fig.5a and b.First,below mean outdoor temperatures of 238C,the NV build-ings were primarily operating within the limits of the ACS,and mean thermal sensations were primarily within Æ0.5.This means that,despite relatively large climatic variations outside,interior conditions remained relatively stable and occupants were able to maintain neutral or close-to-neutral sensations.The few buildings that were operating above or below the ACS limits had corresponding thermal sensations that were,respectively,much warmer or cooler than neutral,as one might expect.Above mean outdoor temperatures of 238C,interior temperatures frequently rose above the ACS limits,with mean indoor operative temperatures clustered around 308C,and simultaneous mean thermal sensations clustered around a mean vote of 1.0.So,while the neutral temperatures for these buildings were calculated to be in the range of 26–278C,the data suggests that these naturally conditioned buildings were not,in fact,able to maintain thermal comfort,even as de ﬁned by the ACS model,for many hours of the day.These uncomfortable buildings came from a range of climates and cultures,including various regions of Pakistan,Australia,Greece,Singapore,Indonesia,and Thailand.As a result,it is dif ﬁcult to generalize about them or to cast them off as being representative of only a singleregion.Fig.5.(a)Indoor operative temperatures in the naturally ventilated buildings of the RP-884database.(b)Thermal sensations in the naturally ventilated buildings of the RP-884database.2Note that not all of the NV buildings in these figures were used in the development of the ACS shown in Fig.3,since some buildings were eliminated from the ACS analysis if their if their regression of comfort vote on operative temperature did not reach statistical significance.R.J.de Dear,G.S.Brager /Energy and Buildings 34(2002)549–561555。

生乳中风味物质特征及来源研究进展

中国畜牧兽医 2024,51(3):1103-1110C h i n aA n i m a lH u s b a n d ry &V e t e r i n a r y Me d i c i n e 生乳中风味物质特征及来源研究进展陈银阁1,2,张养东2,李宁2,张元庆1(1.山西农业大学动物科学学院,太谷030801;2.中国农业科学院北京畜牧兽医研究所,农业农村部奶及奶制品质量安全控制重点实验室,北京100193)摘要:风味是生乳感官评价的重要组成部分,也是乳制品内在品质的综合表现㊂与人的嗅觉㊁味觉㊁触觉相对应,生乳的风味特征可以分别从气味㊁味道㊁口感3个维度分析㊂挥发性化合物不仅是风味的主要来源,也是非常重要的气味贡献物质,生乳中只有部分挥发性化合物有助于形成风味㊂生乳中主要挥发性化合物包括萜类㊁酸类(如C 4~C 12脂肪酸)㊁酮类(如甲基酮)㊁醛类(如壬烯醛㊁庚烯醛)㊁酯类(如γ-内酯)㊁酚类(如对甲酚)及硫化物(如二甲基硫化物)等㊂生乳风味多由挥发性物质决定,但生乳敏感性强,干扰物多,使风味成为一项很难客观把控的质量指标,从而极易影响乳制品的品质㊂因此,在保障生乳新鲜风味的基础上,更需要严格控制多种外界因素对风味的干扰㊂生乳风味与多种因素密切相关,如饲粮㊁饮用水和牛舍环境等㊂目前,饲粮被认为是影响乳及乳制品风味最主要和最敏感的因素,饲粮中碳水化合物㊁脂肪㊁蛋白质等营养成分可通过不同途径影响乳中风味物质,从而改变生乳风味㊂综上,饲粮在很大程度上决定了影响生乳风味的挥发性化合物的组成㊂作者从气味㊁味道㊁口感3个维度阐述生乳风味特征,综述了生乳中的主要挥发性化合物及饲粮㊁饮用水㊁牛舍环境对生乳风味的影响,以期为生乳风味及品质调控提供理论依据㊂关键词:生乳;风味;挥发性化合物中图分类号:Q 592.6;S 823文献标识码:AD o i :10.16431/j .c n k i .1671-7236.2024.03.022 开放科学(资源服务)标识码(O S I D ):收稿日期:2023-09-21基金项目:山西省现代农业产业技术体系牛体系(2023C Y J S T X 13);山西种业创新良种联合攻关项目(2022x c z x 08);山西省基础研究计划自然科学研究面上项目(20210302123424)联系方式:陈银阁,E -m a i l :C Y G 103045@o u t l o o k .c o m ㊂通信作者张元庆,E -m a i l :y u a n q i n g _z h a n g@163.c o m R e s e a r c hP r o gr e s s o nF l a v o u r S u b s t a n c eC h a r a c t e r i s t i c s a n dS o u r c e s i nR a w M i l k C H E N Y i n g e 1,2,Z H A N G Y a n g d o n g 2,L IN i n g 2,Z H A N G Y u a n q i n g1(1.C o l l e g e o f A n i m a lS c i e n c e ,S h a n x i A g r i c u l t u r a lU n i v e r s i t y ,T a i g u 030801,C h i n a ;2.K e y L a b o r a t o r y o f Q u a l i t y a n dS a f e t y C o n t r o l o f M i l ka n dD a i r y P r o d u c t s ,M i n i s t r y o fA g r i c u l t u r e a n dR u r a lA f f a i r s ,I n s t i t u t e o f A n i m a lS c i e n c e s ,C h i n e s eA c a d e m y o fA g r i c u l t u r a l S c i e n c e s ,B e i j i n g 100193,C h i n a )A b s t r a c t :F l a v o u ri s b o t h a ni m p o r t a n t p a r t o ft h e s e n s o r y ev a l u a t i o n o fr a w m i l k a n d a c o m p r e h e n s i v e e x p r e s s i o n o f t h e i n t r i n s i c q u a l i t y o f d a i r y p r o d u c t s .C o r r e s p o n d i n g t o t h e s e n s e s o f s m e l l ,t a s t ea n dt o u c hi n h u m a n ,t h ef l a v o u r p r o f i l e o fr a w m i l k c a n b ea n a l y z e di nt h r e e d i m e n s i o n s :O d o u r ,t a s t ea n d m o u t h f e e l ,r e s p e c t i v e l y .V o l a t i l ec o m p o u n d sa r en o to n l y th e m a i n s o u r c eo ff l a v o u r ,b u ta l s oav e r y i m p o r t a n tf l a v o u rc o n t r i b u t o r ,o n l y so m eo ft h ev o l a t i l e c o m p o u n d s c o n t r i b u t e t o t h e f l a v o u r f o r m a t i o n .T h em a i nv o l a t i l e c o m po u n d s i n r a w m i l k i n c l u d e t e r p e n o i d s ,a c i d s (s u c ha sC 4-C 12f a t t y a c i d s ),k e t o n e s (s u c h a sm e t h y l k e t o n e s ),a l d e h y d e s (s u c h a s n o n e n a l a n d h e p t e n a l ),e s t e r s (s u c h a s γ-l a c t o n e ),p h e n o l s (s u c h a s p -c r e s o l )a n d s u l f i d e s (s u c h a sd i m e t h y l s u l f i d e ).V o l a t i l e c o m p o u n d s a r e t h e d e t e r m i n i n gf a c t o r i n t h e f l a v o u r o f r a w m i l k ,b u t r a w m i l k i s h igh l y s e n si t i v e a n d e a s i l y d i s t u r b e db y ch e m i c a l s u b s t a n c e s ,w h i c hm a k e s t h e f l a v o u r中国畜牧兽医51卷o f r a w m i l k i s d i f f i c u l t t o c o n t r o l o b j e c t i v e l y,t h e r e f o r e f l a v o u r i s h i g h l y s u s c e p t i b l e t o t h e q u a l i t y o f d a i r yp r o d u c t s.T h e r e f o r e,o n t h eb a s i so f e n s u r i n g t h e f r e s h f l a v o u r,i t i sn e c e s s a r y t os t r i c t l y c o n t r o l t h e i n t e r f e r e n c eo fv a r i o u se x t e r n a l f a c t o r so nt h ef l a v o u r.R a w m i l kf l a v o u r i sc l o s e l y r e l a t e d t o a v a r i e t y o f f a c t o r s,s u c ha s d i e t,d r i n k i n g w a t e r a n db a r ne n v i r o n m e n t.A t p r e s e n t,d i e t i s c o n s i d e r e d t ob e t h em o s t i m p o r t a n t a n d s e n s i t i v e f a c t o r a f f e c t i n g t h e f l a v o u r o fm i l ka n dd a i r y p r o d u c t s,a n d t h en u t r i e n t s s u c ha s c a r b o h y d r a t e s,f a t s a n d p r o t e i n s i nd i e t c a na f f e c t t h e f l a v o u r s u b s t a n c e s i nm i l k t h r o u g h d i f f e r e n tw a y s,t h e r e b y c h a n g i n g t h e f l a v o u r o f r a w m i l k.I n s u m m a r y, t h e d i e t l a r g e l y d e t e r m i n e s t h ec o m p o s i t i o no fv o l a t i l ec o m p o u n d s t h a t a f f e c t t h e f l a v o u ro f r a w m i l k.I n t h i s p a p e r,t h e f l a v o u r c h a r a c t e r i s t i c s o f r a w m i l kw e r e e l a b o r a t e d f r o mt h r e ed i m e n s i o n s o f o d o u r,t a s t e a n dm o u t h f e e l,a n d t h em a i n v o l a t i l e c o m p o u n d s i n r a w m i l k a n d t h e e f f e c t s o f d i e t, d r i n k i n g w a t e ra n db a r ne n v i r o n m e n to nt h ef l a v o u ro fr a w m i l k w e r er e v i e w e d,i no r d e rt o p r o v i d e a t h e o r e t i c a l b a s i s f o r t h e f l a v o u r a n d q u a l i t y c o n t r o l o f r a w m i l k.K e y w o r d s:r a w m i l k;f l a v o u r;v o l a t i l e c o m p o u n d s生乳因含有蛋白质㊁脂肪酸㊁矿物质㊁维生素等多种必需营养素而深受消费者喜爱,在人体营养健康方面具有重要地位[1]㊂对乳品行业来说,生乳本身的性能及品质非常重要,其会直接影响生乳的可加工性及后期乳制品中所蕴含的经济价值[2]㊂生乳特有的浓郁风味是引起消费者兴趣的重要特征之一㊂消费者通过风味物质感知生乳感官特性上的差异,如香气㊁味道㊁口感㊂从营养角度来看,基于生乳营养价值的研究已很普遍,但生乳风味特征还没有被充分探索㊂生乳的主要风味物质是挥发性化合物,它们有助于生乳及乳制品的香气形成,并影响消费者的感官感知[3]㊂生乳中挥发性化合物由各类物质组成,主要包括醇㊁醛㊁酯㊁酮㊁酸㊁内酯㊁酚类化合物和硫化合物等[4]㊂生乳风味由化合物间的相互平衡决定,并非所有挥发性成分都会对生乳风味产生影响,而是由化合物之间的相互作用和不同的气味阈值决定[5]㊂随着研究人员对生乳了解的不断深入,除营养价值外,生乳风味价值的研究正在兴起㊂气相色谱-质谱(G C-M S)㊁气相色谱-离子迁移谱(G C-I M S)㊁电子鼻和电子舌等用于研究食品风味特征的分析技术[6-9],正逐步应用于生乳和乳制品风味表征的研究㊂总之,生乳风味不仅是生乳质量的特征,更是影响乳制品质量的重要参数[10]㊂作者旨在总结生乳中风味物质特征,综述对生乳风味起重要作用的挥发性化合物,阐明生乳中风味化合物的来源途径,为生乳感官品质调控提供进一步的理论参考㊂1生乳中风味物质特征风味是生乳最重要的特性之一,是决定消费者可接受性和偏好性的重要因素㊂与人的嗅觉㊁味觉㊁触觉相对应,生乳风味可从气味㊁味道㊁口感3个维度进行分析㊂1.1气味新鲜生乳通常甜美芳香,具有熟气㊁乳香味,不会有牛体和牛舍等异味,口感细腻而平淡㊂大多数食品通过挥发性化合物刺激嗅觉神经而感受气味,这是获取风味㊁评定感官品质的重要方法㊂生乳挥发性化合物是风味的主要来源,只有一小部分挥发性化合物具有风味活性并有助于风味[11]㊂因此,利用气味活性值来确定生乳香气中的关键活性成分,分析具有较高气味活性和强烈香气的挥发性化合物,成为正确评价生乳风味特征的关键㊂1.2味道生乳是由多种成分融合而成的混合体,各物质为其提供甜㊁酸㊁咸㊁苦等多种不同味道㊂微甜源于乳糖,对生乳来说,乳糖几乎是提供甜味的唯一物质;微酸来自柠檬酸㊁磷酸㊁乳酸等酸味物质,乳糖与磷酸㊁柠檬酸等酸味物质平衡;咸味来源于氯;苦味来源于游离的钙㊁镁等㊂各溶质间的相互平衡是决定生乳味道的关键㊂1.3口感生乳的口感常被描述为香浓 ,指香气浓郁,口感浓稠㊂生乳口感丰富的决定因素是乳中固体物含量,主要包括脂肪㊁蛋白质等㊂脂肪会为生乳带来顺滑口感,蛋白质和其他非脂肪固体物带来浓稠㊁涩等口感,如脱脂牛奶口感清淡,不如全脂牛奶口感香醇润滑㊂生乳中的水分含量也是一个不容忽视的重要因素㊂生乳成分由乳固体物与水分组成,水分含量约占88%,乳固体物约占12%[12]㊂乳企业普遍通40113期陈银阁等:生乳中风味物质特征及来源研究进展过降低生乳含水量等加工工艺来提高蛋白口感㊂生乳口感极大可能源自乳固体物成分,较低的脂肪含量或较高的水分占比都会影响口感㊂2生乳中挥发性风味化合物生乳风味非常复杂,由具有香气活性的挥发性化合物决定㊂生乳中挥发性化合物包括萜类㊁酸类(乳脂肪中C4~C12脂肪酸)㊁酮类(甲基酮)㊁醛类(壬烯醛)㊁酯类㊁酚类以及硫化物(二甲基硫化物)等㊂生乳感官特性很大程度上取决于来自脂肪㊁蛋白质或碳水化合物的风味化合物的相对平衡[13]㊂生乳中产生风味成分的一个主要途径是通过乳脂中脂肪酸的脂解或氧化[14](图1)㊂乳脂肪是生乳芳香气味的主要来源,目前已鉴别出120多种乳脂肪风味成分㊂但生乳在储存过程中易发生各种微生物㊁酶或化学反应,从而改变其物理㊁化学和微生物特性,产生挥发性副产物,导致异味甚至变质㊂因此,挥发性化合物的演变对维持生乳风味至关重要㊂图1乳脂在产乳过程的降解途径F i g.1G e n e r a l d e g r a d a t i o n p a t h w a y s o fm i l k f a t d u r i n g m i l k2.1萜类化合物生乳中萜类化合物被证明与牧草的植物组成和牧场放牧有关㊂萜烯是一类植物特异性化合物,天然存在于植物体内,多具有较强气味,如分子质量较小的单萜和倍半萜㊂萜类化合物通过饲草饲喂给动物后经微小改变进入生乳,其在生乳中存在的含量高度依赖于饲草供应水平,与牧草中萜烯比例呈正相关㊂此外,生乳中单萜浓度多大于倍半萜[15]㊂已报道的生乳中最丰富的萜类化合物包括α-蒎烯㊁β-蒎烯㊁柠檬烯和β-石竹烯,其他萜类化合物通常微量存在[16-17]㊂综上,生乳中萜烯含量与牧草组成相关,萜烯也可用作追踪生乳风味来源或奶牛牧草成分等非常有效的标志物㊂2.2酸类化合物酸类化合物来自脂肪分解和微生物发酵等代谢途径㊂在新鲜生乳中,短链及中链脂肪酸(C4~C12)是生乳风味的关键成分㊂乙酸通常是由饲粮转移到生乳中,在青贮饲料中含量较高,该物质具有醋酸味和尖锐气味㊂丁酸是梭状芽胞杆菌的主要产物,同样具有尖锐气味[18],并取决于青贮饲料的质量,可通过饲粮转移到牛奶中㊂发酵乳会具有典型的干酪香甜气味,甚至呈山羊气味[19],它是由酸类化合物己酸导致的㊂除上述酸类物质外,生乳中还检测到辛酸㊁癸酸等酸类物质,辛酸具有典型的肥皂气味[20]㊂2.3酮类化合物众所周知,甲基酮天然存在于生乳中,是由脂肪酸通过氧化降解产生的㊂热处理过程中乳脂降解㊁不饱和脂肪酸的β-氧化及β-酮酸的脱羧都会促进甲基酮的形成㊂丙酮和2-丁酮通常在生乳中少量存在,丙酮具有一种甜美的水果香气,含量为0.8~2.7m g/k g;2-丁酮的风味特征与丙酮相似,含量约0.2m g/k g,对生乳风味贡献不大㊂研究发现,与夏季放牧奶牛所产生乳相比,通常在冬季饲喂青贮饲料的奶牛所产生乳中2-丁酮含量较高[21],它被认为是青贮饲料中常见的一种挥发性化合物,奶牛采食饲粮时经肺脏吸入,由血液运输至乳腺,从而存在于生乳中㊂2.4酯类化合物内酯通常为生乳提供甜美和果香味㊂研究发5011中国畜牧兽医51卷现,饲喂干草的奶牛所产生乳有较浓的甜味,这可能与生乳中较高的γ-内酯水平有关[22]㊂γ-内酯是由C18不饱和脂肪酸通过水合转化为羟基酸后经β-氧化在组织中环化而成,其中,γ-癸内酯㊁γ-十二内酯和γ-十二烷内酯在乳中含量较高㊂大多数酯类均具有水果和花香气味,可最大限度地减少脂肪酸和胺带来的辛辣和苦味[23]㊂2.5醛类化合物研究发现,生乳中相关风味化合物在储存期间浓度的变化主要是由于细菌代谢酶的反应而导致它们形成或转化为其他化合物,或是它们因挥发而损失[24]㊂脂质氧化被认为是富含脂质的乳制品加工或储存过程中品质降低的主要原因[25]㊂除营养损失外,脂质氧化产物(如醛类和酮类)会使乳制品具有不新鲜和氧化的味道[26],甚至在极低浓度下引发异味,如脂肪味㊁塑料味㊁鱼腥味㊁金属或纸板味道㊂生乳脂质氧化最初发生在乳脂球膜的多不饱和磷脂部分,其次是三酰甘油,其中不饱和脂肪酸自氧化产生醛类,如油酸自氧化产生辛醛㊁壬醛㊁癸醛等;亚油酸和亚麻酸等不饱和脂肪酸自氧化产生丙醛㊁己醛㊁2-辛烯醛㊁3-己烯醛等㊂2.6硫化合物硫化合物最初以较低浓度存在于生乳中[27],通常在牛奶热加工过程中大量产生㊂据报道,挥发性硫化合物是生乳热处理后形成煮熟异味的主要原因㊂已确定的与这种煮熟异味有关的挥发性硫化物有硫化氢(H2S)㊁甲硫醇(M e S H)㊁二硫化碳(C S2)㊁二甲基硫醚(D M S)㊁二甲基二硫醚(D M D S)和二甲基三硫化物(D MT S)[28]㊂生乳中H2S浓度会随加热温度而增加[29],其由β-乳球蛋白中含硫氨基酸(半胱氨酸)的巯基产生,是加热乳中形成的主要硫化合物,具有特有的硫磺气味,这可能是生乳形成煮熟风味最重要的因素[30]㊂M e S H和D M D S等硫化物同样具有卷心菜㊁硫磺般气味,D M D S可能是由甲硫醇M e S H氧化形成[28]㊂总之,大多数硫化合物一般在生乳中含量极少,却对风味影响很大,具有独特的气味特征,因其低气味阈值而对生乳风味产生显著影响,但高气味活性和强挥发性使其在生乳中的检测和定量成为一项挑战㊂2.7酚类化合物长期以来,酚类化合物一直被认为是产生牛尿气味的原因,它们通常以葡萄糖醛酸苷的形式随奶牛尿液排出[31],但目前在生乳及乳制品中也已鉴定到烷基酚[32],它们对反刍动物乳制品风味起重要作用,并在低水平下有助于表征特征物种风味㊂研究人员在奶牛㊁山羊㊁绵羊脱脂乳中均发现烷基酚,其为葡萄糖醛酸和硫酸的缀合物㊂牛奶中存在的主要烷基酚是对甲酚,对甲酚具有独特的谷仓风味[33]㊂3-乙基苯酚和4-乙基苯酚已在山羊和绵阳乳中被检测到,是一种特征性的物种相关烷基酚[34]㊂综上所述,生乳中的烷基酚与反刍动物特征物种的乳制品风味相关㊂3生乳中风味物质来源生乳风味物质主要由3个途径形成[35]:①饲粮中风味化合物通过消化道被直接吸收,进入血液系统并到达外周组织(如乳腺);②饲粮及牛舍环境中挥发性化合物经空气扩散被奶牛吸入肺脏中,通过血液扩散至乳腺;③饲粮营养成分经瘤胃代谢形成或由乳中碳水化合物㊁氨基酸㊁脂肪等降解形成(图2)㊂最新的一项研究在生乳中共鉴定出33种挥发性有机化合物,其中13种存在于饲粮和瘤胃中,30种挥发性有机化合物丰度因饲粮配方而异[36]㊂显然,在生乳风味化合物合成途径中,饲粮成为影响生乳风味的一大重要原因[37]㊂下面对生乳风味的来源途径展开叙述㊂3.1饲粮在动物管理因素中,饲粮被认为是影响生乳及乳制品产生特定风味最主要和最敏感的因素㊂乳脂中的挥发性化合物主要与来自不同饮食的风味成分以及在热处理或储存过程中产生的异味有关[38]㊂此外,饲粮中吸收的挥发性次生植物代谢物可能会影响瘤胃微生物群[39],进而影响乳中脂肪酸组成㊂瘤胃微生物对不饱和脂肪酸的氢化作用限制了其转化效率,使乳中脂肪酸组成的调控难以达到理想的效果㊂不同饲粮配方对乳中营养成分的影响存在明显差异,如寡糖组成[40]㊁脂肪酸[41]㊁类胡萝卜素[42]等㊂饲粮中碳水化合物和蛋白质经瘤胃微生物降解产生挥发性脂肪酸,如乙酸㊁丙酸和丁酸等[43],饲粮中纤维比例降低会降低乙酸与丁酸比例[44],提高饲粮中精料比例会提高丙酸产量㊂一些研究同样强调饲粮和生乳之间可能存在直接转移,玉米青贮饲料喂养的奶牛所产生乳中内酯含量很高[45];生乳中乙醇含量被认为主要来自于青贮饲料[46],劣质青贮和各种杂草极易导致生乳异味;饲喂玉米可产生浓郁的奶油味㊁玉米味和甜玉米味[47]㊂总之,有相当数量化合物被认为是从饲粮转移到生乳中,其成分明显影响风味㊂饲粮通过瘤胃代谢或转移气味活性物60113期陈银阁等:生乳中风味物质特征及来源研究进展质影响挥发性化合物组成,从而不同程度地改变生乳风味㊂因此,饲粮已然成为影响生乳风味的一大重要因素㊂图2 饲粮对乳中营养及风味物质合成途径的影响F i g .2 E f f e c t s o f d i e t o n t h e s yn t h e s i s o f n u t r i e n t a n d f l a v o r s u b s t a n c e i nm i l k 3.2 饮用水水质水是奶牛养殖中非常重要却又最容易被人们忽视的营养因素㊂奶牛主要通过直接饮水和采食饲粮2种途径获取日常所需水含量,其中直饮水占比最大,约83%[48]㊂水的味道来源于水中溶解的气体和矿物质,如C l ㊁F e ㊁M n 等㊂周雪巍[49]分析生乳时发现,生乳中F e ㊁C o ㊁M n ㊁P b 和A s 等元素含量与饮用水显著相关㊂张洁[50]发现生乳中污染物重金属P b主要与饮水有关㊂在实际生活中,其来源可能来自输水管道,如水龙头㊁铸铁管等,在养殖场使用消毒剂过程中水龙头老化从而导致P b 析出,奶牛长期饮用有味道的水极易导致生乳产生异味甚至重金属超标㊂此外常见的水质问题还有很多,包括高矿物质含量(盐分过大)㊁高氮含量(硝酸盐和亚硝酸盐)㊁细菌污染㊁蓝绿藻过度生长,以及被石油㊁农药或化肥意外污染等,都会对奶牛健康甚至生乳风味产生不同的影响,仍需要更多试验去研究㊂因而,保证养殖场水质的安全性,不仅对奶牛生命活动尤为重要,更与生乳品质密切相关㊂3.3 牛舍管理及环境牛舍环境优劣直接影响生乳风味㊂牛舍粪便会释放有害气体包括硫化氢及氨气,粪尿中的氮源被微生物分解后形成氨气,逐渐溶解在湿气中,粪尿污水清理不及时,牛舍通风不良,都会严重影响牛舍空气质量,从而导致生乳不新鲜㊁牛舍味重,甚至奶牛出现中毒状况[51]㊂生乳会吸收汽油异味,挥发性物质汽油㊁柴油等放置在挤奶厅或制冷间,制冷罐口密封不严,都会使环境中的各种气味传入生乳致使产生异味;日常为预防传染病,在饲粮中添加中药治疗奶牛疾病时,也易使原料奶吸入药剂味或药气味㊂另外,环境温度㊁湿度㊁光照等也是影响奶牛泌乳从而改变生乳风味的重要因素㊂夏季高温易导致奶牛产生热应激,厌食,喜吃精料,导致饲粮在瘤胃代谢后挥发物乙酸/丙酸比值下降,从而影响生乳风味[52]㊂4 小结与展望生乳风味主要来自于乳中天然存在的挥发性成分,它们因浓度㊁气味活性及相互作用而影响生乳风味㊂生乳中已鉴定出包括酸类㊁醛类㊁酯类㊁酮类㊁酚类㊁萜类及硫化物等几十种挥发性化合物㊂确定关键风味化合物与生乳感官特性之间的关系将有助于更好地了解风味如何受到关键挥发性化合物的影响,理解风味的复杂性,以获得更高的消费者接受度㊂在各种管理条件下,饲粮似乎成为影响生乳风味最敏感的因素㊂生乳中某些化合物成分与饲粮中7011中国畜牧兽医51卷微生物代谢或保存过程中的直接发酵有关,也有一些形成于瘤胃代谢过程从而转移至生乳㊂此外,饲粮中挥发性化合物的分解与转移也对风味产生了明显影响㊂综上所述,生乳中关键风味化合物的分析不仅可用于质量监测,也有助于生产风味更稳定的乳制品㊂生乳中挥发性化合物的特征更能作为一个参数,为消费者提供优质和安全的产品㊂总体而言,不同因素对生乳风味感官特性的影响非常复杂,需更深入地分析风味的来源途径,了解不同条件下生乳风味带来的微小感官差异,以达到最大限度地减少实际生产中生乳的异味风险,为生产加工优质乳制品提供新思路㊂参考文献(R e f e r e n c e s):[1] S T A R K U T E V,L U K S E V I C I U T E J,K L U P S A I T E D,e t a l.C h a r a c t e r i s t i c s of u n r i p e n e d c o w m i l k c u r dc h e e s e e n r i c h ed w i t h r a s p be r r y(R u b u si d a e u s),b l u e b e r r y(V ac c i n i u m m y r t i l l u s)a nde l d e r b e r r y(S a m b u c u s n i g r a)i n d u s t r y b y-p r o d u c t s[J].F o o d s,2023,12(15):2860.[2]王倩.代谢组学分析纯品黄曲霉毒素B1添加和自然霉变饲料对奶牛健康和牛奶品质的影响[D].北京:中国农业科学院,2019.WA N G Q.M e t a b o l o m i c sa n a l y s i so ft h 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以色列奶牛牛舍及其管理

Housing and Management of Dairy Cows in Israel
以色列奶牛牛舍及其管理
Dr. Ezra Shoshani Consular,
Int. Cooperation, Science & Agriculture Foreign Affairs Ministry (MASHAV), ISRAEL
Pagoda 钟楼
Marginal Height
边墙高度
Open ridge
开梁
Width 宽度
Data collection Procedure 数据测定
In every barn (N=39): 2 meteo. Stations perpendicular to wind direction (2.2 m’ above bedding)
• 自由散栏的朝向对牛无影响。
Responses of dairy cow to heat stress
奶牛对热应激的反应
1. Vasodilatation – inefficient due to the coat surrounding her body. 血管舒张－奶牛的被毛限制散热
2. Increasing respiratory rate for dissipating heat from tracheal tract – efficient up to a threshold, in which: 呼吸频率加快加强了消化道产热的散失
与其它途径相比（如冷却系统），和理的牛舍设计是最基本的预防奶牛热应激的途径。
Introduction 引言
• From the literature: 参考文献
• Ambient temperature (AT) inside the barn might be 1◦ to 3◦ C above the outside AT.

以我的农场写篇英语作文

以我的农场写篇英语作文My farm is a small but thriving operation located in the rolling hills of the countryside. It has been in my family for generations, passed down from one hard-working farmer to the next. When I was a young child, I spent countless hours exploring the various parts of the farm, fascinated by the rhythms of the natural world unfolding all around me. Now, as the current caretaker, I am deeply committed to preserving this land and the way of life it supports.At the heart of my farm are the fields where we grow a variety of crops. Acres of golden wheat sway in the breeze, their stalks heavy with the promise of a bountiful harvest. Rows of corn stretch out as far as the eye can see, their green leaves rustling softly. In another section, vibrant red tomatoes ripen on the vine, ready to be plucked and used in all manner of delicious dishes. I take great pride in nurturing these plants from seed to maturity, coaxing the best possible yields from the soil through careful tending and sustainable farming practices.Interspersed among the croplands are our pastures, where our herdof dairy cows grazes contentedly. I can think of few sights more peaceful than watching these gentle creatures munching on lush green grass, their soft eyes regarding me with calm acceptance. Each morning and evening, I make my way to the barn to milk them, a routine that grounds me in the timeless rhythms of farm life. The rich, creamy milk is then used to produce a variety of dairy products, from tangy cheese to thick, velvety yogurt.Of course, running a farm requires more than just tending to the plants and animals. There is also the constant maintenance of the various structures and equipment that make our operations possible. The old wooden barn, with its sagging roof and weathered siding, is a constant source of both challenge and pride. I spend many hours repairing broken boards, reinforcing the foundation, and keeping the interior clean and organized. Similarly, the fleet of tractors, plows, and other machinery must be meticulously maintained to ensure they are ready for the demanding work ahead.One of the most rewarding aspects of farm life, however, is the sense of community that it fosters. Neighbors often come together to lend a hand during the busiest times of the year, whether it's helping with the harvest or pitching in to repair a section of fencing. I, in turn, am always eager to share my knowledge and resources with those around me. It is not uncommon for me to deliver a basket of freshly picked produce to an elderly widow down the road or to offer adviceto a young couple just starting out in the farming life.Beyond the local community, my farm also plays a vital role in the broader ecosystem. The diverse habitats it provides – from the dense woodlands to the meandering streams – serve as a haven for a wide array of wildlife. I take great care to protect these natural resources, ensuring that my farming practices are in harmony with the delicate balance of the land. Wherever possible, I incorporate sustainable techniques that minimize our environmental impact, such as using cover crops to enrich the soil and implementing integrated pest management strategies to reduce the need for harmful chemicals.Of course, running a farm is not without its challenges. The unpredictable weather, fluctuating market prices, and the sheer physical demands of the work can all take a toll. There have been many times when I have felt overwhelmed, wondering if all the hard work is worth it. But then I look out over the fields, see the cows grazing peacefully, and hear the laughter of my grandchildren as they explore the farm, and I know that this way of life is truly priceless.For me, being a farmer is not just a profession – it is a deep-seated connection to the land and a responsibility to steward it for future generations. Every day, I am reminded of the rich history and tradition that I am a part of, and I am driven to ensure that my farmcontinues to thrive long after I am gone. It is a constant source of joy, challenge, and fulfillment, and I wouldn't have it any other way.。

用现在进行时写一篇在火车上的英语作文

用现在进行时写一篇在火车上的英语作文I am riding on a train today! My family and I are going on a big adventure. We are traveling to visit my grandparents who live far away. My little sister is sitting next to me, bouncing up and down excitedly in her seat. She is looking out the window at all the scenery whizzing by."This train is moving so fast!" she exclaims, her eyes wide. I am nodding in agreement. Everything outside is a colorful blur as we speed along the tracks.My mom is sitting across from us, smiling at my sister's enthusiasm. She is reading a book to pass the time during our long journey. My dad is napping a few rows away with his headphones on, the quiet rumble of the train lulling him to sleep.I am feeling antsy, so I decide to get up and stretch my legs. I am carefully making my way down the narrow aisle, gripping the seats to steady myself whenever the train lurches. Up ahead, I can see the dining car. A few passengers are eating meals and sipping drinks there. The servers are swiftly taking orders and delivering plates of food, scurrying back and forth as the train rocks.In the opposite direction, I notice the observation deck at the rear of the train. I amble over and find a few empty seats by the large windows. I am in awe at the incredible views streaming by. I can see miles and miles of green fields and forests in the distance, with the occasional house or barn dotting the landscape.As I am watching the scenery fly past, a little grey bunny suddenly darts across an open field. I sit up straighter in my seat, rubbing my eyes in disbelief. But just as quickly as it appeared, the bunny vanishes into the underbrush. "Wow, did anybody else see that bunny?" I ask the other passengers excitedly, but they aren't paying attention.After my brief adventure exploring, I am making my way back to my seat. I pause in the middle train car where a young family is playing a rowdy game of cards at one of the tables. The two kids are squealing with delight, wholeheartedly enjoying their silly game. Their parents are laughing along, dealing out the cards with dramatically exaggerated motions. I can't help but smile at their joyful silliness.When I return to my seat, my sister is still glued to the window, mesmerized. "What are you looking at?" I ask her curiously. She points outside and I see we are now travelingalong a wide river. The sun is glittering on the water's surface like millions of sparkling diamonds."Isn't it beautiful?" my sister breathes in amazement. I nod slowly, taking in the breathtaking view. We are flying over a bridge that spans the whole river. I can see boats leisurely drifting below us, leaving little wakes in their paths. The people aboard look like tiny specks from up here.After the river, we are plunging into a long, dark tunnel. My sister lets out a startled gasp as we are suddenly engulfed in blackness. I reach out to give her hand a reassuring squeeze as our eyes adjust to the low lights inside the train car.Just as suddenly as we entered it, light is appearing at the end of the tunnel. We are emerging into a whole new landscape of rolling green hills and puffy white clouds drifting lazily across the bright blue sky.Up ahead, I can make out a quaint little village in the distance, with a steeple poking up from a cluster of clay-tiled rooftops. Directly next to the train tracks, a herd of dairy cows is grazing lazily in a grassy meadow, occasionally glancing up at the roaring train with mild disinterest.A whistle blows, signalling that we will soon be stopping at another station to let passengers off and pick up new ones. The train is gradually slowing down, allowing me to more clearly make out the details of the charming village.I notice a bustling market in the town square, with vendors shouting over each other to advertise their delicious fresh fruits and vegetables. A friendly old man in a flat cap is waving slowly at the passing train from his rocking chair on the platform. Schoolchildren are scampering along the sidewalks, their backpacks bouncing on their shoulders.As the train finally grinds to a halt, the doors open to let in a gust of fresh country air. I am taking a deep breath, filling my lungs with the sweet aromas of flowers and freshly mowed grass.Several passengers are getting off here, while new faces are climbing aboard and finding their seats. A mother is struggling up the steps with a stroller, her two toddlers scurrying around her feet excitedly. A young businessman is hurriedly grabbing a window seat, pulling out his laptop to work during the next stretch of the journey.The train lets out an ear-splitting whistle, and we are starting to move again with a jolt. I am leaning out the window to catch one last glimpse of the charming village as we leave it behind.The rolling green hills soon give way to jagged mountains and rocky cliffs in the distance. I can see little wisps of white waterfalls tumbling down the craggy slopes. As we curve around a bend, an absolutely massive, snow-capped mountain emerges directly in our path. I feel like I could reach my hand out and touch it, it is so immense and overpowering.My sister and I are glued to the window, utterly speechless at the majestic sight before us. We are traveling directly through a long, winding tunnel carved into the sheer rock face of the mountain. The darkness surrounds us again, but this time I can make out the craggy stone walls just inches from the。

发酵床对泌乳奶牛健康状况和生产性能的影响

DOI:10.20041/ki.slbl.2023.03.009发酵床对泌乳奶牛健康状况和生产性能的影响岳立，宋红卫，吴卫东（菏泽市食品药品检验检测研究院，山东菏泽274000）摘要：试验旨在研究发酵床与水泥地对泌乳奶牛健康状况和生产性能的影响。

试验设发酵床组与水泥地面组，各选健康的泌乳奶牛30头，通过奶牛体表卫生评分、生产性能和血液生化等指标进行评估。

结果表明：水泥地面组奶牛体表卫生平均分高于发酵床组奶牛39.3%。

发酵床组与水泥地面组奶牛的日产奶量、蛋白质、脂肪、非脂乳固体、相对密度均差异不显著（P>0.05），发酵床组牛乳中体细胞数量显著低于水混地面组（P<0.05）。

发酵床组牛舍相对湿度显著高于水泥地面组（P<0.05），氨气浓度显著低于水泥地面组（P<0.05），温度、噪声两组间差异不显著（P>0.05）。

发酵床组与水泥地面组奶牛白细胞、红细胞、血小板计数，血红蛋白、血总蛋白、总胆固醇含量，谷丙转氨酶、碱性磷酸酶活性差异不显著（P>0.05），发酵床组血清葡萄糖含量显著高于水泥地面组（P< 0.05）。

发酵床组奶牛乳房炎和肢蹄病的发病率低于水泥地面组28.3%。

综上所述，发酵床养殖能够提高奶牛的体表卫生和牛舍舒适度，降低奶牛乳房炎和肢蹄病发病率，从而影响奶牛的生产性能。

关键词：发酵牛床；水泥地面；泌乳奶牛；生产性能；健康状况中图分类号：S815文献标志码：A文章编号：1001-0084（2023）03-0043-05Effects of Fermentation Bed on Health Status andProduction Performance of Lactating Dairy CowsYUE Li,SONG Hongwei,WU Weidong（Food and Drug Inspection and Testing Institute in Heze,Heze274000,Shandong China）Abstract:The experiment aimed to study the effects of fermentation bed and cement on the health status and production performance of lactating dairy cows.The test was divided into fermentation bed group and cement floor group,each selected30healthy lactating dairy cows,and evaluated by the body surface hygiene score,production performance and blood biochemical index.The results showed that the average sanitary score of dairy cows was 39.3%higher than that in the fermentation bed group.The daily milk yield,protein,fat,non-fat milk solid and relative density of the fermentation bed group and the cement ground group were not significantly different(P>0.05), and the number of somatic cells in the fermentation bed group was significantly lower than that of the water mixed ground group(P<0.05).The relative humidity of cowshed in fermentation bed group was significantly higher than that of cement floor group(P<0.05),the ammonia concentration was significantly lower than that of the cement ground group(P<0.05),and the difference of temperature and noise were not significant(P>0.05).The white blood cell,red blood cell,platelet count,hemoglobin,total blood protein,total cholesterol content,alanaminase and alkaline phosphatase activities in the fermentation bed group were not significantly different(P>0.05),and the serum glucose content in the fermentation bed group was significantly higher than that in the cement floor group(P< 0.05).The incidence of mastitis and limb foot disease was lower in the fermentation bed group than28.3%in the收稿日期：2023-03-14作者简介：岳立（1970—），女，山东菏泽人，高级畜牧师，主要从事畜牧推广工作。

四下英语四单元小作文我的农场

四下英语四单元小作文我的农场My farm is a place of tranquility and abundance, nestled amidst the rolling hills and verdant fields of the countryside. It is a haven where I can escape the hustle and bustle of everyday life and reconnect with the natural world. From the moment I step onto the property, I am enveloped by a sense of peace and contentment that fills my soul.At the heart of my farm is a modest but well-tended farmhouse, its weathered wooden siding and charming gables a testament to its long history. The house is surrounded by a lush vegetable garden, where I spend countless hours tending to the rows of leafy greens, vibrant tomatoes, and fragrant herbs. The rhythm of planting, watering, and harvesting is a soothing ritual that grounds me and reminds me of the cyclical nature of life.Beyond the garden, my farm boasts a diverse array of livestock, each with its own unique personality and role to play. In the spacious barn, a herd of dairy cows contentedly chew their cud, their gentle eyes and soft lowing sounds a constant source of comfort. Next to them, a flock of clucking hens scurry about, their feathers a dazzling arrayof colors as they search for juicy worms and scratch in the dirt.Further afield, a small but thriving orchard stands tall, its branches heavy with the promise of ripe, juicy fruit. I take great pride in tending to the apple, pear, and plum trees, carefully pruning and fertilizing them to ensure a bountiful harvest. When the time comes, I gather the fruit with my own hands, reveling in the satisfaction of transforming them into jams, pies, and other delectable treats.One of the most enchanting aspects of my farm is the abundance of wildlife that calls it home. Majestic deer graze peacefully in the meadows, their graceful movements a sight to behold. Flocks of vibrant songbirds flit from tree to tree, their melodious calls filling the air with a symphony of nature. Even the humble earthworm plays a vital role, aerating the soil and enriching the land that sustains us all.As the seasons change, so too does the rhythm of life on my farm. In the spring, the land awakens from its winter slumber, and I eagerly plant the seeds that will nourish us in the months to come. Summer brings a riot of color and activity, with the garden in full bloom and the animals basking in the warm sunshine. Autumn ushers in a time of harvest, as I gather the bounty of the land and prepare for the colder months ahead. And in the winter, the farm takes on a serene, almost ethereal quality, as the bare trees and snow-covered fieldscreate a breathtaking natural tableau.Throughout it all, I am constantly in awe of the resilience and beauty of the natural world. My farm is a living, breathing testament to the interconnectedness of all things, a tapestry of life that unfolds before me each and every day. It is a place where I can slow down, reconnect with the earth, and find a sense of purpose and fulfillment that is often elusive in the modern world.In many ways, my farm is more than just a piece of land – it is a way of life, a philosophy, and a deep-rooted connection to the natural rhythms that have sustained humanity for millennia. It is a place where I can nurture not just the crops and animals, but also my own well-being and sense of place in the world. And as I continue to tend to this sacred land, I am filled with a profound sense of gratitude and a renewed appreciation for the simple joys that come from living in harmony with the earth.。

英语作文外公的农场

英语作文外公的农场Nestled amidst rolling green hills, where the gentle whispers of the wind danced through towering trees, there lay a sanctuary of tranquility and nostalgia known as my grandfather's farm. It was a place where the sun painted the sky with golden hues, casting an ethereal glow upon the sprawling pastures and verdant fields.As a child, I would spend countless hours roaming the farm's sprawling expanse, my imagination soaring as I embarked on countless adventures. The rustling of leaves in the wind transformed into whispers of secrets, and the babbling brook babbling became the voice of a friendly woodland sprite.The centerpiece of the farm was a charming old farmhouse, its white clapboard exterior weathered by time and adorned with climbing ivy. It was here that my grandfather, a man of unwavering strength and a gentle heart, resided. His warm smile and twinkling eyes radiateda timeless wisdom that had been shaped by a lifetime spent tending to the land and raising a family.Each morning, as the first rays of dawn kissed the horizon, my grandfather would rise with the sun, his weathered boots crunching on the gravel path as he made his way to the barn. There, he would tend to his prized herd of dairy cows, his hands deftly milking them as they patiently awaited their morning sustenance.As the sun climbed higher in the sky, I would join my grandfather in the fields, marveling at the rows of vibrant wildflowers that lined our path. He taught me the names of each species, from the delicate bluebells to the cheerful daisies, instilling in me a love for nature that I cherish to this day.Weeding and harvesting were tasks that, while arduous at times, were always filled with laughter and camaraderie. My grandfather had a knack for making even the most mundane chores seem like a grand adventure, his stories and jokes filling the air with an infectious joy.As the sun began its westward descent, casting long shadows across the farm, it was time for the animals to return to their enclosures. The cows, replete from theirday in the pasture, made their way back to the barn, their bells jingling merrily as they greeted their companions.The chickens, too, would flutter and cluck excitedly as they made their way to their coop, their feathers shimmering in the fading light. Watching over them was anold sheepdog named Max, his loyal gaze never straying from his charges.Evenings on the farm were a time for relaxation and reflection. As the stars twinkled above, my grandfather and I would sit on the porch swing, sipping lemonade andsharing stories. He would regale me with tales of his youth, of adventures he had experienced and lessons he had learned.His words, woven with wisdom and experience, painted a vivid tapestry of a life well-lived. They taught me the importance of hard work, perseverance, and the unwaveringbonds of family.As the night deepened, I would retreat to the guest room, the gentle lullaby of crickets and frogs serenading me to sleep. The air was heavy with the scent of blooming jasmine, its fragrance wafting through the open window and filling my dreams with images of the farm's idyllic beauty.My grandfather's farm was more than just a place of residence; it was a sanctuary of love, laughter, and timeless memories. It was a place where I learned the value of hard work, the importance of family, and the enduring power of nature.As the years passed, I grew older and my visits to the farm became less frequent. Yet, the memory of those golden days spent amidst its rolling hills and whispering trees remained forever etched in my heart.Today, my grandfather's farm stands as a testament to the legacy of a life well-lived. It is a place where the past and present intertwine, where the spirit of mygrandfather continues to reside, and where countless new memories are waiting to be made.。

参观农场的作文英文

参观农场的作文英文英文回答：Visiting a farm is a thrilling experience that offers a unique opportunity to connect with nature, learn about agricultural practices, and witness the interconnectedness of life on a working farm.Upon arriving at the sprawling expanse of the farm, we were greeted by the symphony of farm life. The air crackled with the cheerful chirping of birds and the gentle rustling of leaves in the morning breeze. Lush pastures extended as far as the eye could see, teeming with grazing livestock, their contented lowing creating a soothing rhythm in the air.As we ventured deeper into the farm, we encountered a friendly farmer who enthusiastically shared his passion for his work. He explained the intricate process of crop cultivation, from seed selection and soil preparation toirrigation and harvesting. We learned about the challenges and rewards of farming, and the importance of sustainable practices in preserving the delicate balance of the ecosystem.In the barn, we were captivated by the gentle giants of the farm, the cows. Their large, brown eyes gazed upon us with a mixture of curiosity and contentment. We marveled at their rhythmic chewing and the soothing sound of their milk flowing into the milking machine. The farmer explained the importance of dairy farming and the essential role cows play in providing nourishment for our communities.Continuing our exploration, we made our way to the poultry house, where a chorus of clucks and squawks filled the air. Hundreds of chickens roamed freely, pecking at feed and laying eggs in their cozy nests. The farmer emphasized the importance of poultry farming for egg and meat production, and discussed the steps they take to ensure the welfare and health of their birds.As the sun began its descent, casting a golden glowover the farm, it was time to bid farewell to this enchanting place. We left with hearts filled with gratitude and a newfound appreciation for the vital role farms playin our lives. The experience had not only provided us with a glimpse into the world of agriculture but had also reminded us of the interconnectedness of all living beings.中文回答：参观农场是一次激动人心的经历，它提供了与自然接触、了解农业实践和见证农场生活的相互联系的独特机会。

一份参观去农场的新闻报道英语作文

一份参观去农场的新闻报道英语作文全文共3篇示例，供读者参考篇1Hometown Elementary School Students Get Firsthand Look at Life on a FarmBy Jessica Wilson, 5th Grade ReporterLast Wednesday, the 5th grade class from Hometown Elementary took a field trip to Smith Family Farms, a working dairy farm just outside of town. For many of us city kids, it was our first up-close experience with farm animals and the agriculture that puts food on our tables.The big yellow school bus pulled up to the farm around 9am after travelling around 20 minutes from our school. We could immediately smell the unmistakable odors of manure and livestock. "Whoa, what's that stink?" my friend Michael loudly exclaimed, holding his nose. The rest of us giggled nervously, not used to the powerful smells of a real farm.Mrs. Thompson, our teacher, gathered us together as Mr. Smith, the friendly farmer who owns the land, approached to welcome us. "Welcome to Smith Family Farms, kids!" he boomedin a jovial voice. "Who's ready to learn all about agriculture and where your food comes from?"Despite the intimidating new surroundings and aromas, we all cheered enthusiastically. We were definitely excited to get out of the classroom for this unique field trip experience.First up, Mr. Smith led us over to the dairy cow barns. We stared in awe at the massive herd of gentle-eyed cows, numbering over 100. They were littered about eating, resting, and chewing their cud. Up close, I couldn't believe how big they were! Some of the biggest cows towered over us at 6 feet tall.Mr. Smith explained that his dairy farms milks the cows twice a day at 5am and 5pm every day to collect their nutritious milk. He allowed a few of us to gently pet the softer hides of some calmer cows, while teaching us not to approach the cows too quickly to avoid startling them. Petting their warm coats was a fun experience after learning how important dairy cows are for producing milk, butter, cheese, and other products.After the cows, we headed over to the chicken coops to see the laying hens. The series of long coops housed hundreds of clucking chickens. Mr. Smith let us carefully pick up some of the calmer birds and feel how light yet fidgety they were in our grasps. He showed us how to gently collect warm, fresh eggsstraight from the laying nests. We all marveled at the variety of brown, white, and speckled eggshells before placing them back carefully.For me, the chickens were a little more unnerving than the fairly tame dairy cows we saw first. Their beady little eyes, jerky motions, and propensity for sudden squawks made a few students jumpy. But it was still fascinating to see the source of eggs we often eat for breakfast in their own natural habitats.As we took a quick snack break of granola bars and juice boxes, Mr. Smith told us all about the wide fields of plants growing across his family's vast farmland acreage. He drove us over in his rugged pickup truck and we could see endless rows of crops like corn, wheat, tomatoes, and more stretching to the horizon.Mr. Smith showed us how farmers use big machines like tractors and combines to maintain and harvest all those plants over many seasons of planting, fertilizing, and reaping the bounties of nature. I couldn't believe how much backbreaking work goes into producing enough crops to feed families like my own.Lastly, we visited the farm's petting zoo area where we got to interact with smaller animals like pigs, goats, sheep, andponies. The portly pigs snorted and squealed as we tossed them food pellets. A friendly goat nibbled shrubbery right from my hand! We all took turns petting the woolly sheep and snapping Photos with the adorable ponies.By this time, we were all getting pretty worn out and smelled quite...fragrant after getting up close with so many farm animals. But the petting zoo was definitely a fun way to end our virtual journey through the highlights of agriculture and animal life.On the bus ride back to school, Mrs. Thompson had us all write down one mindblowing fact we learned about farming and farm animals that day. I wrote that I was amazed to discover how a single dairy cow can produce as much as 28 liters (6 gallons) of milk per day! No wonder Mr. Smith has to milk that big herd twice daily.My classmate Emily's fun fact focused on the chickens: "Did you know that a fertile chicken egg starts developing a baby chick within 24 hours after being laid?" She felt bad for accidentally leaving some eggs in her bedroom once, thinking creepy chicken embryos might have started growing inside.Meanwhile, Diego's written fact showcased his big takeaway from the crops portion: "One acre of wheat can produce 60 loaves of bread!" He said learning that statistic gave him anewfound appreciation for how much agriculture is required to produce the dietary staples we often take for granted.Michael, who was worried about the animal smells at first, talked about his unexpected new appreciation in his fact: "Pigs are way smarter than I thought - they're actually the 5th most intelligent animal in the world!" He sheepishly admitted farm animals aren't as dumb or gross as he had assumed before.As for me, I think the whole field trip really opened my eyes in a lot of cool ways. I have a much better understanding now of where our food comes from and how hard farmers work to provide it. Cows, chickens, pigs, and crops aren't just abstract concepts anymore - they're living, breathing sources of dairy, eggs, meat, and produce that I'm thankful for.Experiences like this field trip make me appreciate how humans and animals live in a mutually beneficial cycle on this planet. As I get older, I hope to learn more about sustainable farming, ethical treatment of livestock, and making sure we protect the environmental resources that help agriculture thrive. For now though, I'll just be sure to say an appreciative "Thanks farmers!" before my next meal.篇2A Delightful Day at Greenview FarmsBy Ashley Thompson, 8th Grade StudentLast Friday, our 8th grade class took an exciting field trip to Greenview Farms, a local family-owned farm just outside of town. It was a beautiful sunny day, perfect for getting out of the classroom and experiencing a bit of farm life firsthand. I have to admit, I was really looking forward to the field trip as I don't get many opportunities to spend time in rural settings being a city kid.We boarded the bus early Friday morning, buzzing with anticipation about the day ahead. The 45 minute bus ride seemed to take forever, but we passed the time swapping stories and jokes to keep the mood light. As we got closer, the scenery slowly transitioned from urban to rural, with plenty of wide open spaces and fields along the road.When we finally arrived at the farm, we were immediately struck by the peaceful tranquility of the surroundings. Gone were the usual city sounds of traffic and construction, replaced by a calming quiet only disturbed by the occasional moo of a cow or clucking of chickens. The air smelled fresh and earthy, a welcomed change from the car exhaust we're accustomed to breathing at home.Our guide for the day was Jeff, one of the owners who inherited the farm from his grandparents. You could tell Jeff had a deep passion for agriculture and preserving the family legacy built on this land over generations. His excitement was contagious as he provided some background on the history of Greenview Farms and the crops and livestock they raise.Our first stop was the chicken coops, which were housed in a large red barn. I had never been that close to live chickens before, so I was bit apprehensive at first. But Jeff showed us how to properly handle the birds, scooping them up gently and stroking their soft feathers. He even let us feed them, sprinkling corn kernels that they hungrily pecked at. Looking into their beady little eyes, I gained a newfound appreciation for where our eggs actually come from.Next, we headed over to the cow pastures, being sure to watch our step along the way if you know what I mean! The cows were magnificent creatures, lazily grazing on the fields and occasionally mooing at us as we observed them. A few brave souls in our class even got to try their hand at milking the gentle bovines. That milk certainly traveled a shorter distance from teat to bottle compared to what we buy at the grocery store!The horse stables were another highlight, with Jeff introducing us to the majestic animals and their roles on the farm. He talked about the importance of caring for livestock and maintaining their housing, valuing his animals as more than just assets. I was amazed by the sheer size and strength of the workhorses as they stomped around their pens.Of course, no farm tour would be complete without seeing the crops and produce. We trudged through fields brimming with rows of vegetables, inspecting tomato plants, pepper bushes, stalks of corn, and more. Jeff explained their planting and harvesting techniques, emphasizing the farm's commitment to sustainable and ethical agricultural practices without excessive artificial inputs. It was incredible to see firsthand where so much of our food comes from before ending up on grocery store shelves.As the sun began descending in the early afternoon, we wrapped up our festivities with a picnic lunch of farm fresh ingredients. Juicy slices of watermelon, crisp green beans, savory ears of corn, and refreshingly chilled milk hit the spot after venturing around all morning. Our bellies full, we bid farewell to Jeff and the animals before reluctantly reboarding the bus back to school.On the return trip, our class was abuzz rehashing all the sights, sounds and encounters we experienced that day. For many of us city-dwellers, it was our first chance to witness agriculture in action beyond a television screen or textbook. More than just observing farm animals and crops, we developed an appreciation for the hard work and passion it takes to maintain a successful farm operation.I know I'll remember this field trip for years to come. It was an authentic look into a different way of life compared to my urban upbringing. While I don't know if farming is in my future career plans, I do have a profound newfound respect and gratitude for those who toil daily to put food on our tables. A big thanks to Greenview Farms for an educational and delightful day!篇3Student News Report: Eye-Opening Farm Field TripBy Ashley Rodriguez, Greenwood High FreshmanWALTON, NY - Last Friday, our freshman class had the exciting opportunity to take a field trip to Smith Family Farm, a working dairy farm located just outside of town. For many of us city kids, this was our first up-close experience with a real farmand agricultural way of life. The eye-opening day left me with a newfound appreciation for the hard work that goes into producing our food.We arrived at the picturesque farm around 9am after a short bus ride from school. Mr. and Mrs. Smith, a friendly older couple who have owned and operated the farm for over 40 years, greeted us with warm smiles. After a quick introduction, they divided us into smaller groups and the tour began.Our group headed straight for the cow barns, given that dairy is the farm's primary operation. The moment we stepped inside, we were overwhelmed by the strong smells and noises of the hundreds of cows. Mr. Smith explained that they milk around 200 cows twice a day, at 5am and 5pm, using modern milking machines. However, he still gets up even earlier to prep the equipment and guide the cows into the milking parlor.As we watched the cows getting milked, Mrs. Smith pointed out that farm families have to be extremely dedicated, as caring for livestock is a 24/7, 365-day job with no breaks or vacations. The cows have to be fed, milked, and barn areas cleaned daily, regardless of holidays or weather conditions. I couldn't imagine having to wake up at 3:30am every morning, including Christmas, like the Smiths do!After the milking demonstration, we stopped by the maternity area to view the youngest calves. Some were just hours old, still wobbly on their legs but adorably cute. The Smiths aim to have their cows give birth year-round in order to maintain consistent milk production. We learned that newborn calves get colostrum, the first milk from their mother which is rich in nutrients and antibodies, for their first few days before transitioning to regular milk.The highlight for many of us was getting up close with the six-week old calves. We were allowed to gently pet and feed them bottles of milk replacer formula. So many of us city students had never interacted directly with farm animals before. It was such a special experience, but also made us appreciate how labor-intensive raising calves is for farmers.Next up was a wagon ride around the farm's fields, where the Smiths grow corn, alfalfa and other crops to use as feed for their cows. Mr. Smith pointed out the challenges they face from pests, weeds and climate change affecting their crop yields and quality. We also saw some of the high-tech farm equipment used for planting, harvesting, baling hay, and more.On the ride, I couldn't help but think about how underappreciated farmers are. The rise of factory farms andindustrialized food production has disconnected most of us from where our food actually comes from - real family farms like this one. Yet farmers work incredibly hard, sunup to sundown, to keep food on our plates while also beingstewards of the land.After the wagon tour, Mrs. Smith led us to a beautiful red barn that had been converted into a little farm store and cafe area. There, we got to sample some of their products - freshly bottled milk, creamy yogurt, aged cheddar cheese curds, and the most delicious homemade ice cream I've ever tasted! We also had a chance to buy treats and souvenirs from the shop.Finally, it was time to reboard the buses back to school. But not before heartfelt thank-yous to the Smiths for taking the whole day to host us and share their world. And what a world it was - one of constant hard work and uncertainty dealing with livestock, crops, machinery and markets. Yet despite the 24/7 grind, the Smiths clearly took great pride in theirmulti-generational family farm that puts food on our tables.This field trip was so much more than just a day away from the classroom. It was an eye-opening experience that deepened our appreciation for where our food comes from, and the farming families who dedicate their lives to feeding us all. Yes, we learned about dairy farming operations, crops and newtechnology. But more importantly, we students walked away with profound gratitude and respect for the smart, strong, dedicated people like the Smiths who make it all possible. Thank you Smith Family Farm for an unforgettable day!。

参观农场的新闻报道英文作文

参观农场的新闻报道英文作文英文回答：In the heart of the verdant countryside, nestled amidst rolling hills and verdant pastures, our group embarked onan immersive and educational excursion to a local farm. As we stepped onto the sprawling grounds, we were greeted by the symphony of nature—the melodious chorus of birdsong, the gentle bleating of sheep, and the hum of beespollinating the vibrant wildflowers.Our guide, a seasoned farmer with a deep-rooted knowledge of the land, led us through the idyllic landscape. We marveled at the lush vegetable gardens, where rows upon rows of vibrant produce glistened under the warm sunlight. Tomatoes, cucumbers, carrots, and leafy greens—a kaleidoscope of colors and textures—basked in the abundance of nature's bounty.As we continued our journey, we encountered a herd ofmajestic dairy cows grazing contentedly in the sprawling pasture. Their gentle eyes and placid demeanor radiated a sense of serenity. We learned about the intricacies of dairy farming, from the meticulous care and feeding of the cows to the advanced milking technologies utilized to ensure the highest quality of milk.In the nearby barn, we witnessed firsthand the meticulous process of egg production. Hundreds of free-range hens clucked and scratched amidst a cacophony of sounds. We discovered the importance of welfare standards, ensuring that the hens had ample space, natural light, and a nutritious diet to produce fresh and wholesome eggs.Beyond the livestock, the farm also boasted a thriving bee colony. Our guide explained the vital role bees play in pollination, sustaining the delicate ecosystem and contributing to the abundance of nature's fruits. With protective gear adorned, we safely approached the beehives, observing the industrious honeybees as they tirelessly collected nectar and pollinated the surrounding flora.The farm experience culminated in a delightful picnic amidst the tranquil surroundings. As we savored the flavors of farm-to-table delicacies, from freshly baked bread slathered with homemade butter to creamy cheese and succulent strawberries, we deepened our appreciation for the tireless efforts of farmers who nurture the land and provide sustenance for our society.中文回答：我们一行人来到一片生机勃勃的乡间，映入眼帘的是连绵起伏的丘陵和绿意盎然的牧场，我们踏上农场广阔的土地，大自然的交响曲欢迎着我们——鸟儿的鸣唱，绵羊的轻柔咩叫，以及蜜蜂在五颜六色的野花中采蜜的嗡嗡声。

四年级关于写我的农场的英语作文

四年级关于写我的农场的英语作文My Wonderful FarmI am so lucky to live on a farm! It's the most amazing place in the world. Our farm is pretty big, with over 200 acres of land. We have fields for growing crops like corn, wheat, and soybeans. We also have pastures where our cows, pigs, and chickens live.My favorite animals on the farm are definitely the cows. We have about 50 dairy cows that we milk twice a day. In the morning before school, I wake up extra early to help my dad with the milking. The cows are usually already lined up in the barn waiting for us. I give them some hay and fresh water while my dad gets the milking machines ready.Milking the cows is hard work but I don't mind it at all. The cows are so sweet and gentle. They make funny munching sounds as they eat the hay. My dad taught me how to hook up the milking machines to the cow's udders. The machines make a neat "ka-chunk ka-chunk" sound as they pump out the milk. I have to be very careful not to step in any cow pies!After milking, we take the big stainless steel milk canisters out to the dairy truck. The truck driver is always friendly and tells jokes while we load up the canisters. He takes the milk to afactory where it gets pasteurized and bottled or made into cheese, yogurt, and ice cream. I'm glad our cows' milk gets used for so many yummy foods that people can enjoy.On the weekends, I love to spend time with our pigs. We have about 20 pigs on the farm. They are so funny to watch as they roll around in the mud on hot days. Pigs are actually very smart animals. I taught our biggest pig, Wilbur, how to do some cool tricks like spinning in circles and jumping through a hoop. When he does a trick right, I give him an apple treat.Taking care of the pigs isn't all fun and games though. It's a lot of hard work! Every morning and night we have to feed and water them. We use a pitchfork to unstop any backed-up water pipes. Sometimes we have to fix sections of the fence if any pigs have tried to dig underneath and escape. My least favorite job is shoveling out the smelly pig poop from their pens. Phew, it really stinks! But it's worth it because the pig manure is great fertilizer for our vegetable garden.Speaking of our garden, that's one of my favorite spots on the farm. We grow all kinds of delicious fruits and veggies - tomatoes, corn, carrots, strawberries, pumpkins, and more. My job is to pull out any weeds and make sure the plants have enough water. In the spring, it's fun to put the tiny seedlings inthe ground and watch them slowly grow bigger and bigger. By summer and fall, we have amazing fresh produce that my mom uses for our homemade meals. Nothing tastes better than sweet corn we grew ourselves!Another part of the farm I love is the apple orchard. We have rows and rows of different kinds of apple trees. In September, it's all hands on deck for apple picking season. The whole family, plus any friends who want to help, go out into the orchard and pluck the ripe apples right off the trees. We collect them in bushel baskets until every single apple has been picked. It's such hard work, but we have contests to see who can pick the most baskets and we take breaks to drink refreshing apple cider and eat delicious apple fritters.After apple picking, it's time for the best part - making things with our fresh-picked apples! My mom is an amazing baker. She makes the most incredible apple pies, cobblers, crisps, and turnovers. Sometimes we'll still have apples leftover, so we take them over to Bradley Mills Farm to be pressed into yummy cider. On a crisp fall day, there's nothing better than hot apple cider with a dusting of cinnamon on top. We like to have an apple baking contest at the country fair each year and my mom's delicious fried apple pies always win a blue ribbon.Even though there's a ton of work to do every day on the farm, it's all worth it. I love being surrounded by the peaceful sounds of Nature - cows munching on grass, pigs snorting in the mud, birds chirping in the trees. The fresh air and wide open spaces are just what a kid needs to run around, explore, and use their imagination. We have endless room for planting gardens, building forts, riding bikes, and playing games like tag or hide and seek.At night, I fall asleep to the sounds of crickets and hoot owls instead of traffic or sirens like kids in the city. Our farm's starry night skies are brilliantly clear without any light pollution. During summer thunderstorms, I watch in awe as bolts of lightning dance across the sky while the booming thunder shakes our farmhouse windows.Sometimes I'll wake up early just to experience the peacefulness of a farm sunrise. The first rays of light creep over the eastern fields, burning off the morning mist still clinging to the ground. The rooster crows to greet the new day as all the other animals slowly begin to stir. I take a deep breath of the fresh, dewy air, smelling the earthy scents of tilled soil and recent rain. All is calm and quiet, waiting for another busy day on the farm to begin.I know how lucky I am to grow up experiencing this way of life that's quickly disappearing. The farm has been in my family for over 100 years, getting passed down from mygreat-great-grandparents to my great-grandparents to my grandparents to my parents. I hope that when I'm older, I'll get the chance to take over the family farm and keep its legacy alive for many more generations.Living on a farm is definitely not an easy life. It requires patience, hard work, and getting dirty. But in my opinion, it's absolutely the best life there is. Where else can you enjoy such wide open spaces, beautiful nature, caring for animals, and the freshest homegrown food? I feel so fortunate to be able to run free on our farm, breathe the freshest air, be surrounded by animals and crops, and learn vital life skills. Even though farm work can be difficult, there's nothing more rewarding than eating a delicious meal knowing you put in the hard work to grow it yourself. This farm is my entire world and I cherish it with all my heart.。

嗯我的农场英语作文

嗯我的农场英语作文英文回答：My farm is a bustling hub of activity, where the gentle bleating of sheep and the contented clucking of hens create a symphony of rural life. Nestled amidst rolling hills and verdant meadows, my farm is a haven for animals and a sanctuary for my soul.As the sun rises, casting its golden rays over the land, I make my way to the barn. The air is filled with the pungent aroma of hay and the warm scent of animal bodies. With a gentle nudge, I rouse my herd of dairy cows fromtheir slumber. Their large, doe-eyed faces greet me with a soft moo.After tending to the cows, I visit my flock of sheep. Their woolly coats, as soft as cotton, provide warmth against the morning chill. They nibble contentedly on the lush grass, their gentle bleating filling the pasture witha soothing melody.Chickens, with their vibrant feathers and curious eyes, roam freely around the farm. They scratch at the earth, searching for insects, and their cheerful clucks add a lively rhythm to the day. In the corner of the barn, I find my prized rooster, strutting proudly with its flamboyant tail feathers.As the day progresses, I tend to my vegetable garden. Rows of plump tomatoes, crisp lettuce, and sweet carrots thrive in the warm summer sun. I carefully irrigate the plants, ensuring they receive the nourishment they need to flourish.In the afternoon, I check on my beehives. The industrious bees buzz tirelessly, collecting pollen and nectar from the surrounding flowers. Their honey, a golden elixir, is a testament to the sweet rewards of nature.As the sun begins its descent, casting a warm glow over the farm, I gather my animals for the night. The cowsreturn to their stalls, the sheep huddle together for warmth, and the chickens settle into their cozy coop.My farm is more than just a place of work; it is a sanctuary where I find peace and tranquility. The animals, with their gentle spirits and playful antics, bring joy to my life. And as I watch over them, I am filled with a sense of purpose and contentment.中文回答：我的农场是一个繁忙的活动中心，绵羊的轻轻叫声和母鸡满足的咯咯声创造了一曲乡村生活的交响乐。

四年级下册乡下课后词语编成一个英语作文

四年级下册乡下课后词语编成一个英语作文全文共3篇示例，供读者参考篇1Title: My Summer at Grandpa's FarmThis past summer, my parents decided it would be a great idea for me to spend a few weeks at my grandpa's farm in the countryside. At first, I was a bit hesitant because I'm used to the hustle and bustle of city life. However, after just a few days on the farm, I grew to love the refreshing rural atmosphere.When I first arrived, Grandpa gave me a tour of the whole farm. He showed me the lush meadows where his cows graze, the vast fields where he grows crops like corn and wheat, and the quaint barn where he keeps his livestock and farming equipment.I was amazed by how vast and well-kept everything was. Grandpa takes immense pride in maintaining his farmland.Every morning, I would wake up to the melodious sounds of songbirds chirping outside my bedroom window. The crisp country air felt so pure and refreshing compared to the polluted city air I was accustomed to. After getting dressed, I'd head down to the kitchen where Grandma would have a hearty farm-freshbreakfast waiting – eggs straight from the chicken coop, thick slices of bacon, hot biscuits with fresh butter and jam, and tall glasses of creamy milk.Once our bellies were full, Grandpa and I would head out to tend to the chores around the farm. We'd start by collecting eggs from the chicken coop. Those brown speckled egg shells were so different from the plain white ones I was used to seeing at the grocery store. Next, we'd refill the water troughs for the cattle and horses to drink from. I was always amazed at how much water those big animals could guzzle down, especially on hot summer days.My favorite part was getting to ride Grandpa's old horse, Bucky. At first I was nervous since I had never been on a horse before. But Grandpa showed me how to gently brush Bucky's coat, pick out rocks from his hooves, and properly mount him from his left side using the sturdy saddle and bridle. Once I was settled in the saddle, Bucky and I would leisurely trot around the pastures while Grandpa kept a close eye on me. The rhythmic swaying of Bucky's stride was relaxing and home on his back felt like the highest perch to survey Grandpa's picturesque farmland.In the afternoons when it got really hot outside, Grandpa and I would take shelter in the cool, shaded barn. He'd spinfascinating tales about what farm life was like back when he was a young boy. I loved hearing his animated stories about hilarious pranks he played, daring adventures he went on, and challenges he overcame while learning to become a farmer. Grandpa has lived such an intriguing life!On lazy summer evenings, our whole family would congregate on the porch to catch a breath of the crisp evening breeze. We'd snack on slices of Grandma's fresh-baked pie while watching the sunset paint the sky in vibrant oranges, pinks and purples. Occasionally, a deer family would cautiously wander into the fields to graze on the tall grass. Seeing those elegant animals in their natural habitat was magical.As dusk fell, thousands of fireflies would begin blinking their luminous bodies in the fields. My cousins and I would have so much fun chasing after those shimmering lights, cupping them in our hands for a moment, then setting them free again to rejoin the sparkling dance. The clear star-filled night skies were another simple, yet marvelous country pleasure that can't be properly appreciated in the city with all its light pollution.On hot summer nights, Grandpa would set up some large fans to blow cooling breezes into our bedrooms. Nothing beats falling asleep to the sound of whirring fans and cricketsserenading outside in the dark. I looked forward to waking up to another joy-filled day on the farm.While there were definitely aspects of the countryside that took some getting used to - like learning to appreciate moments of peace and quiet instead of constant noise and stimulation - I came to truly cherish the simple pleasures of farm life by the end of my stay. I'm so grateful Grandpa and Grandma opened my eyes to the wonders and beauty of their rural world. Their farm will forever remain a blissful summer haven in my childhood memories.篇2My Countryside AdventureThis summer, my family and I went on a wonderful excursion to the countryside. It was such a unique and riveting experience!I had never truly appreciated the pastoral beauty of the rural areas before this trip.We left our urban home and embarked on our journey early one morning. As our vehicle traversed the winding rural routes, I couldn't resist staring out the window in awe. The scenery was so bucolic and picturesque. Vast verdant meadows stretched as far as the eye could see, speckled with vibrant wildflowers. Majesticmountains majestically pierced the horizon. It was like a lush, natural tapestry.Eventually, we reached our destination - my uncle's rustic farmhouse nestled in a secluded hamlet. I excitedly disembarked and drank in the refreshing country air. It smelled so crisp and rejuvenating compared to the smog of the city. Nearby, my uncle's equine companions grazed lazily in their pasture, paying no mind to my arrival. Their docile amblings seemed to epitomize the unhurried, tranquil pace of rural living.My aunt emerged from the farmhouse, warmly greeting us with open arms and a plate of scrumptious homemade treats fresh from the hearth. As we caught up, I overheard the melodious trills of songbirds in the trees surrounding the property. Their mellifluous melodies provided a charming natural soundtrack.After being shown to our lodgings, I wasted no time in exploring the area with my cousin, who resided at the farm year-round. We first stopped by the rustic, dilapidated barn out back. Despite its ramshackle appearance, it absolutely exuded an aura of bucolic charm and rustic splendor.Venturing inside, I was immediately struck by the permeating aroma of musty hay and warm animal hides. Itsmelled so earthy and organic - the complete antithesis of those artificial air fresheners they pump into shopping malls back home. My cousin's menagerie of farmyard animals regarded us curiously as we strolled through their enclosures.The resident mare whinnied a greeting, wisps of her flaxen mane dancing in the gentle breeze drifting through the barn's open windows. A few rambunctious young porkers raucously rooted around in their pen, snuffling enthusiastically as we passed by. A speckled hen dutifully tended to her clutch of quiescent eggs nestled in a bed of hay. Even the old billy goat, with his shaggy coat and curved horns, bestowed us with a condescending glare. It was all so novel and fascinating compared to the domesticated pets back home!Next, my cousin guided me out to the fields, where the crops swayed hypnotically in the zephyrs. My aunt and uncle's cornucopia of fruits and vegetables grew in orderly rows, soaking up the golden rays of the summer sun. We ventured down the furrowed aisles, my cousin identifying each plant and describing its unique cultivation requirements. I was amazed by the vast variety - they had everything from plump ruddy tomatoes to piquant peppers to luscious berries drooping heavily from their vines.As we strolled, I playfully chased the iridescent dragonflies drifting past on their gaily colored wings. Occasionally, a virescent praying mantis would dart onto one of the plants, remaining camouflaged and motionless as we approached. My cousin delighted in pointing out these fleeting natural marvels to me. He clearly had an intimate understanding and appreciation for this rural environment.The days swiftly fell into a wonderful, languid rhythm. Each morning, my cousin and I eagerly set out to explore another beckoning trail or wooded copse near the farm. We clambered across babbling brooks and rustled through tall grasses, frequently startling timid rabbits or sneaking up on majestic deer cautiously grazing. If we grew weary, we'd find a shady arbor and indulge in a light repast of fresh berries or vegetables pilfered from the fields.As the sun began its descent in the evenings, we'd meander back through the fields towards the warm, welcoming beacon of the farmhouse. There, my aunt would dish out hearty portions of succulent homemade fare for our famished crew. Thick slices of warm bread slathered in fresh butter. Pitchers brimming with cool milk frothed from their own dairy cows. My favorite wasalways the rich, savory vegetable soups lovingly crafted from their crops.After supper, we'd settle on the quaint veranda to observe the bespeckled canopy of night gradually unveil itself. Cuddled in cozy blankets with steaming mugs of herb tea, we'd point out the twinkling chiaroscuro of fireflies meandering lazily through the twilight. As the glimmering stars emerged to grace the velvety sky, my cousin would try identifying the different constellations for me. I always felt so rejuvenated and at peace in those tranquil moments.Too soon, our idyllic sojourn drew to its inevitable end. As we prepared for our departure, my heart felt heavy with melancholy. I had fallen in love with the simplistic splendor of the countryside life. More importantly though, I developed a profound new appreciation for the cycles of nature and the human interdependence with it. The rustic charms, the agricultural bounties, the unhurried pace - I realized it was all so vital and something we city folk often took for granted.On our drive departing the pastoral utopia, I couldn't help but feel a tinge of longing watching the picturesque scenery gradually recede in the rear window. However, I smiled knowing this countryside adventure had sown the seeds for a lifelongconnection to the rural environment. Though my permanent home would likely always be in the urban sprawl, I vowed to one day have a quiet country cottage of my own for frequent respites back to rustic tranquility. I would make sure to share this countryside appreciation with my own future family. For though cities are amazing marvels in their own right, we must never neglect celebrating the incredible pastoral majesty that also surrounds us.篇3A Delightful Day in the CountrysideI could scarcely contain my excitement as our rusty old wagon trundled along the winding dirt road, carrying our family towards my grandparents' quaint farmhouse in the picturesque countryside. Though the journey was arduous, spanning many a rugged mile, I didn't mind in the slightest, for I adored spending time amid the verdant pastures and serene tranquility of rural life.As we approached the ramshackle fence bordering their property, my heart leapt with joy at the sight of my beloved grandmother emerging from the main entrance, waving animatedly with her gnarled yet caring hands. "Welcome,welcome!" she called out, her raspy voice brimming with warmth.I scampered out of the wagon and into her embrace, breathing in the comforting aroma of freshly baked bread that always seemed to cling to her floral print dress.After exchanging joyous greetings with my doting grandparents, I eagerly followed my grandfather towards the rustic barn out back. As we ambled past the verdant vegetable patch and well-trodden chicken coop, he regaled me with tales of the bountiful harvest they had reaped in autumn. I listened with rapt attention, marveling at how their calloused hands had nurtured every tendril and sprout into vibrant, nourishing life.The barn itself was a wondrous place, crammed with tools and implements whose purposes I could scarcely fathom, yet their sturdy craftsmanship spoke volumes of the arduous toil required for rural existence. Grandfather pointed out the massive tractor, its faded red paint chipped in places, but its imposing stature a testament to its might. With great gravitas, he expounded on its vital role in tilling the fields each spring, breaking up the soil and preparing it for the year's planting.As the balmy morning bled into a radiant afternoon, Grandmother summoned us inside for a repast of her legendary home-cooked fare. My mouth watered in anticipation as wesettled at the well-worn oak table, gleaming platters piled high with succulent roast chicken, buttery mashed potatoes, and crisp seasonal vegetables from the garden. I couldn't resist smothering my portion with Grandmother's velvety brown gravy before eagerly tucking in, savoring each morsel of the wholesome, rustic cooking.After our hearty meal, my belly pleasantly sated, I was thrilled when Grandfather proposed a jaunt through the verdant meadows and pristine woodland trails bordering their property. Clad in sturdy overalls and well-worn boots, I trotted alongside him as he pointed out the indigenous flora and fauna thriving in this rural idyll. Vibrant wildflowers of every conceivable hue dotted the lush greenery, while squirrels and rabbits scampered amongst the towering oaks and maples. All the while, birds serenaded us with their mellifluous melodies from the boughs above.As the golden sun began its descent, bathing the countryside in a warm, honeyed glow, Grandfather and I settled upon a mossy knoll to rest our weary legs. In a contented hush, we simply drank in the pastoral splendor surrounding us, the gentle whispers of the meadow grasses swaying in the evening breeze like nature's own sweet lullaby. In that sublime moment, Ifelt an overwhelming sense of serenity and belonging, as if my soul were as deeply rooted in this rural soil as the mighty oaks themselves.Our reverie was finally broken by Grandmother's faint calls beckoning us back for supper. As we retraced our steps through the dusky twilight, I committed every precious moment of this soul-nourishing day to memory: the earthy aromas, the naturalistic symphony, the simple pleasures of a life steeped in nature's bountiful gifts. Though my heart would soon return to the hustle and bustle of city living, I knew a part of me would forever remain in this halcyon countryside haven with my beloved grandparents.。

在农场饲养奶牛英语作文

Dairy farming is an essential agricultural practice that provides a significant source of nutrition to people around the world.Raising dairy cows on a farm involves various aspects,including selecting the right breed,providing proper nutrition,ensuring a healthy environment,and managing the milking process.Choosing the Right Breed:The first step in raising dairy cows is selecting the appropriate breed.Holsteins are the most common dairy cows due to their high milk production.However,other breeds like Jerseys,Guernseys,and Brown Swiss are also popular for their specific qualities such as higher butterfat content or adaptability to different climates.Feeding and Nutrition:A dairy cows diet is crucial for maintaining their health and milk production.They require a balanced diet consisting of forage,grains,and minerals.Silage,hay,and pasture are common forage sources,while grains like corn and soybean meal provide necessary energy.Its also important to supplement their diet with vitamins and minerals to prevent deficiencies.Housing and Environment:Dairy cows need a clean and comfortable environment to thrive.Barns should be wellventilated,dry,and equipped with proper bedding.The cows should have enough space to move around and lie down comfortably.Regular cleaning and disinfection of the barn are necessary to prevent the spread of diseases.Health Management:Regular health checks are vital to ensure the wellbeing of the cows.This includes monitoring for common diseases like mastitis and ensuring that the cows are vaccinated against preventable illnesses.Good hygiene practices,such as washing udders before milking,can also reduce the risk of infections.Milking Process:The milking process is a daily routine that requires careful handling to avoid injury to the cows.Modern dairy farms often use milking machines,which are efficient and reduce the risk of contamination.The milking process should be done at consistent times each day to maintain a regular milk production cycle.Reproduction and Herd Management:Effective herd management includes planning for the reproduction of dairy cows.This involves keeping track of the cows estrous cycles and using artificial insemination or natural mating to ensure a steady supply of calves.Good recordkeeping is essential fortracking the health,milk production,and reproductive history of each cow.Sustainability and Ethical Considerations:Modern dairy farming also focuses on sustainability and ethical treatment of animals. This includes implementing practices that minimize environmental impact,such as managing manure effectively and using renewable energy sources.Additionally,ensuring the welfare of the cows by providing them with a stressfree environment and humane treatment is paramount.In conclusion,raising dairy cows on a farm is a complex process that requires attention to detail in every aspect,from selecting the breed to managing the health and welfare of the animals.By following best practices in dairy farming,farmers can contribute to a sustainable food supply and ensure the quality of milk produced.。

GEA DairyRobot R9500 自动奶牛机说明书

GEA DairyRobot R9500 Uniquely efficient as single or multi box:automated milking at any time2 · GEA DairyRobot R9500Ideal prospects formilk productionPremium milk qualityOptimal milk harvest, superior udder care and impeccable hygienefrom teat to tankEffective work environmentErgonomic workspace with user-friendly display and navigationNon-stop productivityOutstanding system reliability allows efficient cow flow andeffective workflowsFuture-proof partnershipTop-class, innovative service packages from GEA dealersaround the worldReliable investmentHigh yield with minimal expenditure of energy, resourcesand maintenanceGEA DairyRobot R9500 · 3Whether single box or multiple boxes combined as multibox system: your cows decide by themselves, when they want to be milked.DairyRobot R9500 automatically takes care of premium quality milk and an excellent teat condition. That frees up resources to make your daily planning and routines more flexible and effective. The modern, functional design, large touchscreen display and exemplary ergonomics of DairyRobot R9500 greatly simplify data monitoring, while its manual support features make it especially easy to handle special need cows. DairyRobot R9500 also allows for an individualized approach to maximize your farm’s operational efficiency because this exceedingly compact milking box can be seamlessly integrated into your preferred barn design.Premium milk qualityOptimal milk harvest Superior udder and teat care Proactive hygiene management Smooth and safe milk transportation4 · GEA DairyRobot R9500Premium milk quality · 5Consistent precision starts in the cupThe milking stall module of DairyRobot R9500 works consistently and indpendently,day or night. Cows are creatures of habit and welcome the standardized, precise milking routine that takes place in the openly designed box. Each step – from teat cup attachment to teat stimulation, cleaning or pre-dipping in applicable countries, pre-milking and milking, all the way through to post-dipping – is part of a uniform, quick and comfortable process that takes place in-liner – in one single attachment, for each quarter. The consistent routine, impeccable hygiene and gentle protection within the teat cup are the keys to excellent milk quality!Perfect teat protection from the beginning: With DairyRobot R9500, complete milking procedures take place “in-liner”, inside the teat cup in one single attachment. Teat stimulation begins as soon as the teat cup attaches, gently preparing the udder for milking.Hygienically safe: Once the teat cup is attached, cleaning or pre-dipping begins depending upon the country-specific regulations, Optimal milk harvest: While milking, the light-weight, suspended MilkRack and milking cluster can easily adapt to the cow’s natural movements, exerting no unnecessary leverage on the udder. Additional, patented sensors monitoring the flow from each quarter while measuring milk volume continuously in the flow-through.Optimal udder care: When the individual quarter finishes milking, the post-dipping process begins. The dipping agent is evenly and economically distributed throughout the fine pores and wrinkles of the teat skin, providing ideal protection against mastitis pathogens. Through automated udder health care, each cow exits the DairyRobot R9500 perfectly protected for the next milking.A t t a c h m e n t – S t i m u l a t i o n C l e a n i n g - F o r e -s t r i p p i n g M i l k i n g P o s t -d i p p i n g - De t a c h m e n tQuality control at every udder quarter: cell count sensor DairyMilk M6850GEA DairyMilk M8650 is the first somatic cell count system in the world to focus on each udder quarter individually during the entire milking process. This early detection system alerts you at the very first sign. That helps you minimize treatment time, safeguard the healing process, and ensure the continuous productivity of your healthy herd. Its’ superior monitoring technology gives you key benefits for ultra-efficient animalmanagement – now and in the future. The innovative somatic cell count sensor is miles ahead of other measuring methods. Based on patented EPT technology, the system analyses milk flow at each udder quarter individually and continuously, giving your GEA automated milking system unmatched efficiency. Above all, the DairyMilk M6850 does not even need resources or reagents. Boost your early detection capabilities to protect the health of your herd and to produce premium milk!Premium milk quality · 7Intelligent internal logisticsWhile the unit conveniently milks your cows for you, the DairyRobot R9500 also tends to the steady flow of perfectly fresh milk. The milk receiver, valves and frequency-controlled pumps in the receiver unit take care of a smooth •Co ws ap pr ec iat e t he ca lm, c on sis te ntm ilk ing ro ut ine p ro vid ed b y Da iry Ro bo t R9500•Op tim al m ilk h ar ve st an d su bs eq ue ntp os t-d ipp ing su sta in th e lon g-te rm h ea lth o f t he en tir e h er d•GE A co oli ng sy ste m s a nd th e i nt ell igent ta nk co nt ro l u nit m ax im ize yo ur sa vin gs p ot en tia l a nd o pt im ize yo urm ilk m an ag em en tErgonomic workplace and maximum comfortfor operator and cowReal-time display and user-friendly navigationFlexible scheduling of managerial tasksSmooth workflowsThe appeal of modern-day managementWith its innovative functions, GEA’s DairyRobot R9500 allows you to design and organize the tasks of daily herd management more efficiently than ever before. Just tap the touchscreen to see key production data. Because the DairyRobot R9500 can be integrated seamlessly into your existing barn design, you can monitor and tend to selected cows quickly and easily. All activities can be quickly completed in a clean and efficient working environment with great technology. Efficient workplaceThe smart manager’s high-tech toolThe GEA DairyRobot R9500 incorporates highly innovative functions on a large touchscreendisplay. In Live View mode, real-time events can be monitored in easy-to-read graphs. You can alsoeffortlessly switch the control panel to monitor all the key production parameters. The intuitiveinterface greatly simplifies handling, and the system automatically alerts you to any changes.With such sophisticated software, you can manage your herd better than ever!Focus on the essentialsWith an unobstructed view of each cow and easy access to the udder, the operator can freelyintervene in the milking process at any time. A system integrated mechanical milking arm shiftsthe milking cluster into an ideal position below the cow so each teat cup can attach in a matter ofseconds. Kick-proof LED lighting illuminates the cow’s udder for full visibility. Your special needcows can be handled more efficiently and comfortably than ever before.m ob ile ac ce ss up on re qu es t•M od er n, co m pu te riz ed w or kp lac e w ithrm an ce an d co ns ist en t m ilk•Sm oo th p ro ce sse s, he alt hy h er d pe rfoon yo ur D air yR ob ot R9500yie ld ar e d ire ct pa y-o ffs, a nd th e r et ur ninv es tm en t c an b e r ap idl y r ea ch ed14 · Non-stop productivity Non-stop productivityHigh system reliabilityEffective workflows and flexible scheduling Total transparency of resource usageInnovative service packages and minimal downtimesGEA’s philosophy for complete successYou can achieve high throughput by letting your cows decide when to go to the milking robot. Soon after installation, a sense of calm settles over the barn, and cows grow quickly accustomed to a relaxed, rhythmic cycle of feeding, resting and milking. Automated milking frees up time and resources, making daily planning more flexible and routines more effective. Enhanced tools, such as gate control and manual support components, make it especially easy to tend to cows that require special attention. Whether you integrate one milking box or more into your operation, all milking activities can be conveniently controlled from one central milking and management center.Even more economical as Multibox configurationGEA DairyRotor R9500 makes it possible: up to three boxes can be connected to one Supply Unit. This way, they share one vacuum pump, compressor, milk and calf milk line and tank connection. The multibox configuration increases the efficiency, reduces the complexity by using less equipment and lowers the usage of water and energy. Also existing installations are now expandable with two additional boxes!Non-stop productivity · 1516 · Non-stop productivity Optimized design, higher throughputEfficiency gains thanks to numerous design optimizations and a camera system of the newest generation: the new shape of the entrance and exit doors and the reshaped end frame enable an even better positioning of all kind of cows inside the box and a completely undisturbed milking process for the cow. The feeding trough is now hydroformed, has an optimized feed supply and a very clever trough cover concept. This avoids feed losses andreduces the time that the cows stays in the box after milking. Combining all these aspects, your throughput will potentially increase by 4%!Safe and speedy attachmentA G5 Time-of-Flight (TOF) camera on the MilkRack detects the position of the cow’s teats to automatically and precisely apply the teat cups on the teats. This TOF principle allows for maximum attachment reliability in a matter of seconds.Easy to enter and exit – and provides a perfect fit during milkingThe spacious entrance area is designed to lead each cow into an ideal position for attachment. When the gate closes, the preset box length automatically adjusts the feeding trough to accommodate each cow for a perfect and comfortable fit. After milking, the feed trough swings to the side. At the same time, a divider on the trough moves upwards, preventing access to the feed bowl. Now there is no tasty reason for the cow to stay in the box any longer, so the next one can enter immediately!17MilkRack with high-tech featuresExtremely robust and reliable, GEA ’s MilkRack is also incredibly lightweight. Its ultra-flexible plastic cover keeps the equipment clean, and if the cow kicks, a feedback mechanism enables the mechanical milking arm to maneuver away. The milking arms can be adjusted flexibly or fixed, with no possibility of the teat cups touching the floor. That helps to prevent contamination and provide an optimal environment for clean, hygienic milk production.Space-saving ingenuityThe compact, space-saving Supply Unit contains all the components that provide the milking robot with cleaning, dipping and disinfection agents as well as water supply and compressed air. It also controls the flow of milk to the filter, buffer tank and bulk tank.Non-stop productivity · 19No interruption in productionEven while the bulk tank is being emptied and cleaned, there’s no interruption to production. The automated milking system simply continues collecting the milk in an interim buffer tank, and the DairyRobot R9500 remains available for use. The cows can maintain their usual rhythm and milk loss will be prevented!18 · Produktivität rund um die UhrConvenient calf milk managementGEA DairyRobot R9500 makes calf management easy. With justa few clicks, the milk of the cow can be separated and givento her calf, either by bucket or milk taxi. Thanks to the cleversystem, the herd’s offspring are well nourished; getting all thenutrients they need to grow healthy and strong.Individual barn planning also enables free cow traffic. In this case, the cows have unrestricted access to the milking system, the feeding table and the•E c o n o m i c u s e o f l ab o rc r e a t e sfl e x i b i l i t yf o r d a i l y p l a n n i ng a n dh e l p s t o s t re a m l i n er o u t i n e s•T o o l s f o r m o n i t o r i ng a n d m e as u r e m e n tk e e p y o u o n t o p o f r es o u r c e c o ns u m p t i o n,m a i n t a i n i n g f u l l t r a n s p ar e n c y a t a gl a n c eMultibox configuration with Guided Exit Single box configuration with selection after milkingFuture-proof partnershipPremium service expertiseGlobal networkInnovative customer care packages and online serviceShared growth and profitability around the worldOur certified GEA dealers work side-by-side with dairy producers around theworld, enabling that we as a manufacturer stay close to the industry’s growingand changing needs. Our solutions and services are ideally designed tosuit individual requirements, often exceeding expectations. We – as yourmanufacturer – along with our GEA distribution partners, work hand-in-handwith you to achieve profitability and growth together.When it comes to service and maintenance, the DairyRobot R9500 gives you peace of mind. GEA ’s robust and proven milking technology allows high performance and very long operating times. Our easy-to-maintain design accommodates direct access to the components during operation. Online diagnostics can be performed to maximize operations, and spare parts can be replaced with short downtimes. GEA provides great conditions for quick, low-cost maintenance to help keeping downtime to a minimum!• In no va tiv e s er vic e p ac ka ge s a voidi ng d ow nt im es• H igh yi eld w ith m ini m al ex pe nd itu re o f e ne rg y,re so ur ce s a nd m ain te na nc e • Ex pe rt co ns ult ing 365 d ay s a year• O ne -o f-a -k ind m ilk ing an d m anag em en t c en te rwi th G EA ’s re no wn ed d air y t ec hn ology ex pe rti se26 · GEA DairyRobot R9500Notes9997-2014-010 / P S C 1001050200 / 9502020199 © G E A F a r m T e c h n o l o g i e s G m b H . W e r e s e r v e t h e r i g h t t o m o d i f y t h e c o n s t r u c t i o n a n d d e s i g n i n a l l c a s e s . N o v e m b e r 2018GEA Group is a global technology company with multi-billion euro sales operations in more than 50 countries. Founded in 1881 the company is one of the largest providers of innovative equipment and process technology. GEA Group is listed in the STOXX ® Europe 600 Index. In addition, the company is included in selected MSCI Global Sustainability Indexes.We live our values.Excellence • Passion • Integrity • Responsibility • GEA-versityGEA GermanyGEA Farm Technologies GmbH Siemensstraße 25 - 27D-59199 BönenPhone +49 23 83 93 7-0 Fax+49 23 83 93 8-0************。

农场的英文作文

农场的英文作文Title: The Heartbeat of the Countryside: A Day on the Farm Dawn breaks softly over the verdant expanse, painting the sky in hues of lavender and gold. It's a symphony of colors that heralds the beginning of a day on the farm—a place where time seems to move at the rhythm of nature's breathing. Here, amid the rustic charm and the earthy scents, life unfolds in its most genuine form, a testament to the unwavering spirit of rural living.The early chirps of sparrows and roosters announce the wake of the land, as the farm stirs from its slumber. The first rays of sunlight pierce through the gables of the barn, illuminating the scene with a warm, welcoming glow. In this tranquil world, every task begins with intention and is carried out with a sense of purpose that resonates through the day.The farmers, the custodians of this Eden, emerge from their homes with a spring in their step and a smile on their lips. They are the keepers of the land, the weavers of the countryside's tapestry. Their hands—calloused by years of toil and affection—are instruments of creation, capable of nurturing life from the soil.A typical day on the farm commences with the morningfeeding of the animals—pigs, cows, chickens, and sheep—each one a character in this rural narrative. The clanging of milk pails and the swish of feed being scattered create a morning chorus that is both boisterous and comforting. Animals respond with their unique expressions of contentment, whether it be the contented lowing of dairy cows or the gentle clucking of hens.As the sun climbs higher, the fields call out for attention. Tractors rumble to life, humming like giant iron insects, ready to embark on their daily choreography. Farmers climb aboard, their faithful companions in these ballets of cultivation. The swoosh of the plowshare cutting through the earth, the whirr of irrigation systems, and the soft plod of hooves as horses contribute their strength to the day's endeavors.Lunch often finds the farmers back at their homesteads, where tables are laden with harvests from their labor. Meals are simple yet hearty, a blend of vegetables freshly plucked from the ground, meats smoked to succulence, and baked goods that fill the kitchen with an inviting aroma. It's a moment of reprieve, where conversations flow as freely as the stream that borders the farm, and laughter is as melodic as the birds that serenade the afternoon.As afternoon fades into evening, the work continues at a more leisurely pace. Maintenance of the farm's infrastructure becomes the focus; mending fences, tending to machinery, and ensuring that the ecosystem remains in balance. Nature's own symphony accompanies these tasks—the whisper of the wind through the leaves, the distant mooing of a cow returning to the herd, and the occasional bleat of a lamb seeking its mother.As night approaches and the sun prepares to dip below the horizon, a sense of fulfillment permeates the air. Tools are put away, sweat is wiped clean, and the final tasks are completed with a sigh of satisfaction. The farmhouse lights flicker on, casting a warm glow against the twilight. Inside, families gather, sharing stories of the day and making plans for the morrow.In this cycle of sowing and reaping, of dawn's first light to dusk's fading glimmer, the farm stands as a testament to the enduring spirit of those who till the land. It's a microcosm of life—a place where joy and labor coexist in harmony, bound together by the thread of hope and the promise of prosperity.This is more than just a description of a day on the farm; it's a celebration of a way of life—one that honors tradition,welcomes innovation, and upholds the virtues of dedication, sustainability, and community. The farm is not just a location but a living, breathing entity that embodies the very essence of rural vitality.。

喂养农场的动物英语作文

喂养农场的动物英语作文下载温馨提示:该文档是我店铺精心编制而成，希望大家下载以后，能够帮助大家解决实际的问题。

文档下载后可定制随意修改，请根据实际需要进行相应的调整和使用，谢谢!并且，本店铺为大家提供各种各样类型的实用资料，如教育随笔、日记赏析、句子摘抄、古诗大全、经典美文、话题作文、工作总结、词语解析、文案摘录、其他资料等等，如想了解不同资料格式和写法，敬请关注!Download tips: This document is carefully compiled by theeditor. I hope that after you download them,they can help yousolve practical problems. The document can be customized andmodified after downloading,please adjust and use it according toactual needs, thank you!In addition, our shop provides you with various types ofpractical materials,such as educational essays, diaryappreciation,sentence excerpts,ancient poems,classic articles,topic composition,work summary,word parsing,copyexcerpts,other materials and so on,want to know different data formats andwriting methods,please pay attention!1. Living in the barn, the animals were a symphony of rural life. Each day, they danced with the sun, their daily routine a rhythm all their own.2. The cows, with their gentle mooing, were the heartof the dairy. They grazed in the lush pastures, theirudders full of creamy milk, a testament to their hard work.3. Pigs, plump and content, snored in their pens, their slop a tasty treat. They were the farmers' helpers, turning waste into treasure.4. Chickens clucked and pecked, their coop a fortressof eggs. Their cheerful chirping filled the air, a cheerful soundtrack to the farm's quiet corners.5. The pigs' squeals were sometimes the only sound inthe night, a lullaby to the moon. They were the guardiansof the barn, their presence a reminder of the cycle of life.6. The horses, majestic and free, grazed on the open fields, their hooves echoing on the hard earth. They were the farm's pride, their power and grace a sight to behold.7. The farm was a living ecosystem, each animal playing its part. They were not just creatures, but living stories, each one unique and interconnected.8. And so, in the heart of the barn, these animals thrived, their lives a simple, unspoken testament to the beauty of rural living.9. The farmer, a silent observer, watched it all, a smile on his face, content in the knowledge that his farm was a sanctuary for these creatures.10. This was the farm, a living, breathing entity,where the animals and the land coexisted in perfect harmony, a testament to the simple, unadorned charm of country life.。

cow中文翻译

cow中文翻译cow的中文翻译是“奶牛”或“母牛”。

下面是一些关于cow的用法和中英文对照例句：1. 奶牛(nǎi niú) - milk cow- The farmer milks the cow every morning. 农民每天早上挤奶牛。

- Cows provide us with milk and dairy products. 奶牛为我们提供牛奶和乳制品。

2. 母牛(mǔ niú) - female cow- The mother cow protects her young calf. 母牛保护她的小牛犊。

- The farmer bred his cows for beef production. 农民养殖他的母牛用于肉类生产。

3. 奶牛场(nǎi niú chǎng) - dairy farm- The dairy farm has hundreds of cows. 这个奶牛场有数百头奶牛。

- They built a new barn on the cow farm. 他们在奶牛农场建了一个新的牛棚。

4. 奶牛品种(nǎi niú pǐn zhǒng) - cow breed- Holstein is a popular cow breed for milk production. 黑白花奶牛是一种常见的奶牛品种。

- The farmer raises Jersey cows for their high butterfat content. 农民饲养泽西奶牛因其高脂肪含量。

5. 肉牛(ròu niú) - beef cattle- They raise Angus cows for beef production. 他们养殖安格斯牛用于肉类生产。

- The farmer sold his herd of beef cows at the market. 农民在市场上出售了他的一群肉牛。

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T H E R M A L C O M F O R T O F D A I R Y C O W S I N B A R N W I T H O P E N-S I D E D C O N S T R U C T I O NIvana Knížková1, Petr Kunc1, Marie Koubková2, Jan Flusser31Research Institute of Animal Production Uhøínìves,104 00 Praha 10, Czech Republic, phone: 00420/2/67711747, fax: 00420/2/67710779, e-mail: knizkova@vuzv cz,kunc@vuzv.cz, 2Czech University of Agriculture, phone: 00420/2/24382951, fax:00420/2/24382946, e-mail: koubkova@af.czu.cz, 3Institute of Information Theory and Automation, Academy of Sciences, phone: 00420/2/66052357, e-mail: flusser@utia.cas.cz The objective of this experiment was to evaluate the influence of natural ventilation on the thermal comfort dairy cows /housed in barn with an open-sided construction with plastic blinds/, by means of the changes of surface body temperature. The measurements by thermography were carried out in 2 stages with cycles, where the open-sided construction was opened or closed fully. The dairy cows responded promptly to these changes by the changes of body surface temperature, the differences in the temperature values were significant. Natural ventilation ensured adequate heat comfort of housed animals. Closed open-sided construction caused undesirable changes in microclimate.Keywords: open-sided construction, dairy cows, body surface temperature,thermography IntroductionAnimal welfare is one of the basic prerequisites of success in large-scale breeding farms. One of the most important factors that influence animal welfare is the microclimate in the barn which is characterised by the air temperature, relative humidity, air flow and cooling index. Changes in these values may cause excessive stress of the thermoregulatory mechanism, disturb metabolism and lower thOn the basis of this knowledge, the following objectives have been set: to investigate the influence of natural ventilation on the heat comfort of housed cows, evaluated by means of the changes of body surface temperature.Material and methodsThe measurement was carried out in a reconstructed stable (loose housing with cubicle beds and bedding) for 300 dairy cows with natural ventilation and an open-sided construction with plastic blinds during May 1997.The measurements were carried out in two stages with cycles:I.s t a g e(S T) - cycles(CY):1/ 10.00 - 10.30 a.m. - open-sided construction fully opened2/ 10.30 - 11.30 a.m. - open-sided construction closed by means of plastic blinds3/ 11. 30 - 12.30 a.m. - open-sided construction fully openedI I.s t a g e(S T) - cycles(CY):1/08.00 - 08.30 p.m. - open-sided construction closed2/08.30 - 09.30 p.m. - open-sided construction fully openedThe air temperature (T), relative humidity (RH), air flow (AF) and cooling index (CI) were measured during every cycle.The changes of body surface temperatures were measured in 12 dairy cows (Czech Pied cattle) by thermovision set AGA 880 during each cycle. The changes of body surface temperature were evaluated in 4 zones: body forepart(BF), barrel(B), hindpart(H) and udder(U). CM-SOFT computer program was used for data and thermograms analyses.ResultsAir temperature, relative humidity, air flow and cooling index were increased and decreased in dependence on closed or opened open-sided construction. The dairy cows responded promptly to these changes by the changes of body surface temperature, the differences in the temperature values were significant between 1. and 2 CY (I.ST) for BF [P< .05] and for B and H [P< .01], between 2. and 3. CY (I.ST) for H [P< .05] and between 1. and 2.CY (II.ST) for BF,B and H [P< .01]. But no significant differences were observed in U.Results are detailed in the following the chart.___________________________________________________________________ ________T RH AF CI BF B H UST CY o C % m/s W/m2 o C o C o C o C___________________________________________________________________ ________I. 1. 21.7 49 1.75 336 31.38 31.11 31.04 33.032. 25.2 52 0.08 142 31.85 32.03 32.08 33.39differ. 3.5 3 1.67 194 0.47** 0.92* 1.03* 0.372. 25.2 52 0.08 142 31.85 32.03 32.07 33.393. 24.4 46.5 2.00 432 31.37 31.36 31.22 33.32differ. 0.8 5.5 1.93 290 0.48 0.67 0.85** 0.07II. 1. 22.7 68 0.10 156 33.42 33.34 33.18 34.282. 16.2 66.5 0.35 346 31.86 31.91 31.36 33.95differ. 6.5 1.5 0.25 190 1.56* 1.43* 1.82* 0.34___________________________________________________________________ ________* P<.01** P<.05ConclusionIn this case, natural ventilation ensured adequate heat comfort of housed animals. Closed open-sided construction caused undesirable changes in microclimate. The dairy cows responded promptly to these changes by the changes of body surface temperature. No significant differences were observed in udder. These responses of body surface temperature in cows to microclimatic factors manifest a very good adaptation to temperature differences.The observation has proved that the thermographic method is suitable for the evaluation of heat comfort of animals in dependence on the changes of microclimatic conditions in the stable.R e f e r e n c e sBrouèek,J.(1997). Effect of low temperatures on dairy cattle. Polnohospodarstvo, 43, 2, 1997: 135-153Brouèek,J.(1997). Effect of high temperatures on dairy cattle. Polnohospodarstvo, 43, 7, 1997:522-542.Doležal,O.- Pytloun J.-Motyèka,J. (1966)Technologie a technika chovu skotu. Svaz chovatelù èeského strakatého skotu ÈR, 1996: 184.。