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1、SUSTAINABLE DAIRY PRODUCTION SYSTEMS可持續(xù)的奶牛生產(chǎn)系統(tǒng)可持續(xù)的奶牛生產(chǎn)系統(tǒng)Larry D. SatterRetired from退休于U. S. Dairy Forage Research Center,美國(guó)奶牛粗飼料研究中心U. S. Department of Agriculture Agricultural Research Service美國(guó)農(nóng)業(yè)部-農(nóng)業(yè)研究部andProfessor Emeritus名譽(yù)教授Dairy Science Department奶??茖W(xué)系University of Wisconsin, Madison威斯康辛大學(xué),麥迪森

2、WE KNOW IN THE FUTURE THAT:我們知道,在將來(lái):1.World petroleum supplies will soon start decreasing, with consequent increases in energy costs.世界石油供應(yīng)將開(kāi)始下降,而能源消耗將增加。2.Nitrogen fertilizer prices will continue to scalate due to high energy input into manufacture of nitrogen fertilizer.由于氮肥的生產(chǎn)消耗大量的能源,氮肥的價(jià)格將繼續(xù)攀升。3

3、.Global warming will force reduction in green- house gas emissions, with CO2 and CH4 being the main concerns in animal production.全球變暖將迫使我們減少溫室氣體的排放,在畜牧生產(chǎn)中CO2 和 CH4是最值得關(guān)注的溫室氣體。OUTLINE目錄目錄1.Energy flow in milk production 牛奶生產(chǎn)過(guò)程中的能量流2.Feed resources available for milk production 牛奶生產(chǎn)可獲得的飼料資源3.Can milk

4、 production from grazing lands be improved? 放牧系統(tǒng)的牛奶生產(chǎn)能否改進(jìn)?4.Issues related to sustainability of livestock production systems 關(guān)于家畜生產(chǎn)系統(tǒng)的可持續(xù)性EXAMINATION OF ENERGY FLOW IN MILK PRODUCTION檢查牛奶生產(chǎn)中的能量流向檢查牛奶生產(chǎn)中的能量流向Energy in Feed (100)總能總能Digested (67)消化能Feces (33)糞能Urine (4)尿能Methane (6)甲烷能Heat of Rumen Fe

5、rmentation (6)瘤胃發(fā)酵產(chǎn)熱Metabolizable (51)代謝能Net Energy (32)凈能Heat Increment (19)熱增耗Maintenance (Eventually converted to heat)維持凈能(最終轉(zhuǎn)化成產(chǎn)熱)Production (Deposited in milk, body tissue, fetus)生產(chǎn)凈能(沉積在牛奶、體組織、胎兒中)EFFECT OF LEVEL OF MILK PRODUCTION ON EFFICIENCY OF FEED USE產(chǎn)奶量對(duì)飼料利用效率的影響產(chǎn)奶量對(duì)飼料利用效率的影響EFFECT OF

6、LEVEL OF MILK PRODUCTION ON METHANE PRODUCTION PER kg MILK生產(chǎn)水平對(duì)單位牛奶甲烷產(chǎn)氣量的影響生產(chǎn)水平對(duì)單位牛奶甲烷產(chǎn)氣量的影響EFFECT OF LEVEL OF PRODUCTION AND DIET ON EFFICIENCY OF LAND USE IN DAIRY FARMING (VandeHaar, 1998)Grazing1Confined Feeding without By-Products2Confined Feeding with By-Products3Milk Yieldkg/yr per cow5,0005,

7、00010,0005,00010,000Feedkg of DM/yr per cow6,0505,8708,1205,9508,380Land RequiredHa/yr per cow0.540.660.970.300.49Protein Productionkg/Ha359295371642731Efficiency of Land Use%443354576881All high quality pasture no other feeds234% alfalfa, 26% corn silage, 26% corn grain, 12% soybeans325% alfalfa, 2

8、5% corn silage, 13% corn grain, 2% soybeans, 12% corn gluten feed, 10% cottonseeds, 10% wheat middlings, 1% blood meal4Protein and energy yield per ha from dairy farming relative to the protein and energy yield from soybeans and corn grown for direct human consumption.產(chǎn)奶量和日糧類型對(duì)養(yǎng)牛業(yè)土地利用效率的影響產(chǎn)奶量和日糧類型對(duì)養(yǎng)

9、牛業(yè)土地利用效率的影響(VandeHaar, 1998)放牧1指定日糧(未使用副產(chǎn)品)2指定日糧(使用副產(chǎn)品)3產(chǎn)奶量kg/年 *每頭5,0005,00010,0005,00010,000飼料kg 干物質(zhì)/年*每頭6,0505,8708,1205,9508,380所需土地公頃/年*每頭0.540.660.970.300.49蛋白質(zhì)產(chǎn)量kg/公頃359295371642731土地利用效率%443354576881全部為高質(zhì)量的牧草,沒(méi)有其他飼料。234% 苜蓿, 26% 玉米青貯, 26% 玉米, 12% 豆粕325%苜蓿, 25%玉米青貯, 13%玉米, 2%豆粕, 12% 玉米蛋白粉, 10

10、% 棉籽, 10% 麥麩, 1% 血粉4奶牛場(chǎng)每公頃的蛋白和能量產(chǎn)量相對(duì)于直接供人類消費(fèi)的大豆和玉米的蛋白和能量產(chǎn)量的百分比。Milk Production Per Cow in the United States Over the Past 100 Years(VandeHaar and St-Pierre, 2006, J. Dairy Science 89:1280-1291)在過(guò)去的一個(gè)世紀(jì)里美國(guó)奶牛的單產(chǎn)變化曲線FEED RESOURCES AVAILABLE FOR MILK PRODUCTION牛奶生產(chǎn)可利用的飼料資源牛奶生產(chǎn)可利用的飼料資源EFFICIENCY OF LAND

11、USEBy-productsMilling (wheat and rice)Fruit and VegetableDistillers and Brewers GrainsCottonseedCrop ResiduesCorn StalksWheat and Rice StrawSweet Potato VinesPasture (non-arable land)Forage (arable land)Improved PastureCorn SilageAlfalfaGreen chopped small grainsGrainCornSmall GrainsEnergy From Feed

12、 In Milk(10-20 units)Milk ProductionArable Land Required Per 3,000 kg milk = .1 -.15 Ha(20 Units)(80 Units)Energy In Feed (100 units)土地利用效率土地利用效率副產(chǎn)品粉料(小麥和水稻)水果和蔬菜酒糟和啤酒糟棉籽農(nóng)作物秸稈玉米秸麥秸和稻秸甘薯馬鈴薯的蔓秸牧草 (非可耕土地)粗飼料 (可耕土地)人工改良牧場(chǎng)玉米青貯苜蓿谷草谷物玉米小粒谷類作物飼料轉(zhuǎn)入牛奶的能量(10-20 單位)產(chǎn)奶量可耕土地需要量:每3噸牛奶 = .1 -.15 公頃(20 單位)(80 單位)飼料中

13、的能量 (100 單位)NUTRIENT CONTENT OF RELATIVELY HIGH QUALITY BY-PRODUCT FEEDS1FeedDigestible Energy-1X2 Mcal/kgNet Energy-3X3 Mcal/kgCrude Protein %NDF %Brewer grains, dried3.381.7129.247.4Corn distillers grains, dried3.721.9729.738.8Corn gluten feed, dried3.431.7323.835.5Citrus pulp, dried3.441.706.924.

14、2Cottonseeds (whole)3.551.9423.540.1Rice bran3.762.0515.526.1Wheat bran3.231.6117.342.5For comparison:Corn grain3.852.019.49.5Corn silage2.991.458.345.01National Research Council, 200121X = intake at maintenance level33X = intake at three times maintenance level相對(duì)高質(zhì)量加工副產(chǎn)品的營(yíng)養(yǎng)濃度含量相對(duì)高質(zhì)量加工副產(chǎn)品的營(yíng)養(yǎng)濃度含量飼料消化

15、能-1X2 Mcal/kg凈能-3X3 Mcal/kg粗蛋白 %NDF %啤酒糟, 干3.381.7129.247.4白酒糟,干3.721.9729.738.8玉米蛋白粉,干3.431.7323.835.5柑橘皮,干3.441.706.924.2全棉籽3.551.9423.540.1米糠3.762.0515.526.1麥麩3.231.6117.342.5比較比較:玉米3.852.019.49.5玉米青貯2.991.458.345.01National Research Council國(guó)家研究委員會(huì), 200121X =維持水平33X = 3倍維持水平NUTRIENT CONTENT OF RE

16、LATIVELY LOW QUALITY BY-PRODUCT FEEDS相對(duì)低質(zhì)量的加工副產(chǎn)品的能量濃度相對(duì)低質(zhì)量的加工副產(chǎn)品的能量濃度Feed飼料Digestible Energy消化能-1XC P粗蛋白% of DM1Mcal/kg2% of DMWheat straw麥秸442.044.8Corn stover玉米秸57-5.9Corn cobs玉米芯512.313.0Rice straw稻草45-4.2Barley straw大麥秸47-4.1For comparison:比較Corn grain玉米943.859.5Corn silage玉米青貯662.998.31Morrison

17、 Feeds and Feeding, 19592National Research Council, 2001SHOULD FEEDS THAT ARE LESS THAN 50% DIGESTIBLE ENERGY (MOSTLY CROP RESIDUES) BE INCLUDED IN LACTATING COW DIETS?泌乳奶牛日糧中是否應(yīng)該添加能量消化率低于泌乳奶牛日糧中是否應(yīng)該添加能量消化率低于50的飼料原料(大部分為農(nóng)的飼料原料(大部分為農(nóng)作物秸稈)作物秸稈)Probably Not ! !可能不行!At most, only small amounts should be

18、 in the diet unless we improve the quality of the low quality crop residues.除非我們能夠改善低質(zhì)量作物秸稈的質(zhì)量,否則即使要添加也只能是少量的IS THERE ANYTHING WE CAN DO TO IMPROVE THE QUALITY OF STRAW AND CORN STALKS?有什么辦法可以改善麥秸、玉米秸質(zhì)量么?有什么辦法可以改善麥秸、玉米秸質(zhì)量么?YES ! !有!有!In-vitro dry matter disappearance (IVDMD) of corn stalks harvested

19、 over time. (Berger et al., 1979, JAS 49:1312)玉米秸體外測(cè)定干物質(zhì)消化率隨收割時(shí)間的變化曲線CHEMICAL TREATMENT OF CROP RESIDUES CAN IMPROVE DIGESTIBILITY BY 10 20 %化學(xué)處理可以使作物秸稈消化率提高化學(xué)處理可以使作物秸稈消化率提高1020%1.Ammonia氨: 2-3 g / 100 g DM Applied either as anhydrous or aqueous forms.存在固、液兩種形式2.Calcium hydroxide氫氧化鈣: 3-5 g / 100 g

20、DM3.Sodium hydroxide氫氧化鈉: 2-3 g / 100 g DM Is more difficult to work with, and increases sodium residues in the soil. 顯效慢、易在土壤中造成殘留TWO WAYS TO ACHIEVE ACCEPTABLE LEVELS OF DIGESTIBILITY IN TOTAL DIET兩種處理方法使日糧消化率最終達(dá)到標(biāo)準(zhǔn)水平兩種處理方法使日糧消化率最終達(dá)到標(biāo)準(zhǔn)水平Better Way較好的方法較好的方法=+Average Digestible Forages + By-Product

21、s中等質(zhì)量的粗飼料和副產(chǎn)品Acceptable in Digestibility達(dá)到標(biāo)準(zhǔn)的消化率High Digestible Corn Grain高消化率谷物Poor Way較差的方法較差的方法+=High Digestible Corn Grain高消化率谷物Acceptable in Digestibility達(dá)到標(biāo)準(zhǔn)的消化率Low Digestible Crop Residues低消化率的作物秸稈ISSUES RELATED TO SUSTAINABILITY OF LIVESTOCK PRODUCTION SYSTEMS可持續(xù)發(fā)展的家畜生產(chǎn)系統(tǒng)可持續(xù)發(fā)展的家畜生產(chǎn)系統(tǒng)Issues R

22、egarding Sustainability of Livestock Production Systems Relate To:家畜生產(chǎn)系統(tǒng)可持續(xù)性涉及:家畜生產(chǎn)系統(tǒng)可持續(xù)性涉及:1.Excretion of Nitrogen (primarily ammonia release to the atmosphere, and nitrate contamination of water) 氮的排放(主要是排入大氣的氨和硝酸鹽對(duì)水的污染)2.Excretion of Phosphorus (excessive enrichment of surface waters) 磷的排放(富營(yíng)養(yǎng)水)3

23、.Release of Methane (global warming) 甲烷排放(全球變暖)4.High Energy (hydrocarbon) Inputs (consumption of non-renewable resources, and contribution to global warming) 攝入高能量物質(zhì)(碳水化合物),消耗不可再生資源,并導(dǎo)致全球變暖。Nitrogen Issues氮的問(wèn)題氮的問(wèn)題Water quality水質(zhì)1.Nitrate leaching to groundwater 硝酸鹽滲入地下水2.Nitrate enrichment of coast

24、al waters, causing excessive algae growth and hypoxic conditions. 沿海水中硝酸鹽濃度增加,導(dǎo)致海藻大量生長(zhǎng),導(dǎo)致水污染。Nitrogen Issues (continued) 氮的問(wèn)題(續(xù))氮的問(wèn)題(續(xù))Air Emissions 氣體排放1.Acid rain 酸雨2.Excess fertilization of fragile environments 富營(yíng)養(yǎng)的脆弱的環(huán)境3.Formation of particulates (2.5 ). 在大氣中形成懸浮微粒4.Nitrous oxide formation and g

25、lobal warming. 形成笑氣(一氧化二氮)和全球變暖5.In poultry and swine houses ammonia concentration can directly affect human and animal health. 雞舍和豬舍氨濃度直接影響人和動(dòng)物的健康Dairy Cows奶牛奶牛Feedlot Steers育肥場(chǎng)育肥場(chǎng)Phosphorus Issues磷的問(wèn)題磷的問(wèn)題Phosphorus stimulates algae growth in fresh water bodies, causing lakes and streams to become

26、green with algae. Eventually the lakes become low in oxygen as the excess algae decomposes, causing fish kills. 磷刺激清水中藻類的生長(zhǎng),導(dǎo)致河流湖泊變綠。最終湖泊由于藻類的大量分解含氧量降低,導(dǎo)致魚類死亡Agricultural activities are responsible for 50-80% of the P entering lakes and streams. 農(nóng)業(yè)生產(chǎn)產(chǎn)生的磷占排入湖泊河流的磷總量的50-80% 。PHOSPHORUS REQUIREMENT OF

27、LACTATING COWS泌乳奶牛磷的需要量泌乳奶牛磷的需要量WE OVERFEED PHOSPHORUS TO OUR DAIRY COWS!我們給奶牛飼喂的磷過(guò)量了!我們給奶牛飼喂的磷過(guò)量了!CAN WE REDUCE IT?我們可以減少些么?我們可以減少些么?Current status of P nutrition of lactating dairy cows milking 9100 kg/305 d lactation305天產(chǎn)奶量天產(chǎn)奶量 9100kg的泌乳奶牛磷的營(yíng)養(yǎng)狀況的泌乳奶牛磷的營(yíng)養(yǎng)狀況NRC Recommendations (1989 and 2001)NRC推薦量

28、推薦量(1989 and 2001)Dietary Phosphorus (% of DM)日糧磷含量日糧磷含量(% of DM)Beginning Signs of P deficiency開(kāi)始表現(xiàn)磷缺乏開(kāi)始表現(xiàn)磷缺乏X X0.300.350.400.5020011989Amount Dairy Producers Feed實(shí)際生產(chǎn)中的飼喂量實(shí)際生產(chǎn)中的飼喂量PHOSPHORUS FEEDING RECOMMENDATIONS (NRC, 2001)1磷的推薦量磷的推薦量Milk ProductionEstimated DM IntakeP Requirementkg/dlb/dkg/dlb

29、/dg/day% of diet DM255520.344.762.30.32357723.657.979.60.352459926.959.296.90.365512030.066.0113.10.381 For Holstein cow weighing 680 kg and producing milk with 3.5% fat, 3.0% true protein, and 4.8% lactose. Cow is 90 days in milk.適用于體重適用于體重680 kg ,乳脂3.5%,乳蛋白3.0%,乳糖4.8%,DIM90天的奶牛2 For cows in very e

30、arly lactation, NRC suggests diets with 0.42% P 對(duì)于剛剛開(kāi)始泌乳的奶牛,對(duì)于剛剛開(kāi)始泌乳的奶牛,NRC推薦日糧磷含量推薦日糧磷含量0.42% Phosphorus and Reproduction磷與繁殖性能磷與繁殖性能CHARACTERISTICS OF ESTROUS BEHAVIOR FOR LACTATING COWS FED DIETS CONTAINING 0.37% or 0.57% P (Lopez et al., 2002)飼喂含飼喂含P0.37% 或或 0.57% 日糧的泌乳奶牛發(fā)情表現(xiàn)日糧的泌乳奶牛發(fā)情表現(xiàn)0.37% Pn=

31、1590.57% Pn=174P-valueDuration of estrus, hr發(fā)情持續(xù)時(shí)間,小時(shí)8.78.70.99Total mounts, n爬跨次數(shù),次數(shù)7.57.80.68Total mounting time, sec總爬跨時(shí)間,秒25.824.50.59Average duration of standing events, sec接受爬跨平均持續(xù)時(shí)間,秒3.43.40.76REPRODUCTIVE MEASURES FOR LACTATING COWS FED DIETS CONTAINING 0.37% or 0.57% P飼喂含飼喂含P 0.37% 或或 0.57%

32、 日糧的泌乳奶牛繁殖性能測(cè)定日糧的泌乳奶牛繁殖性能測(cè)定0.37% P 0.57% PP-valueDays to first natural estrus產(chǎn)后第一次發(fā)情日期68670.87Conception rate at first AI, % 第一次人工授精受胎率,%39.442.00.67Overall conception rate at 30 d, %30天總受胎率,%34.338.00.35Days open 空懷天數(shù)1121160.45Services per conception平均配種次數(shù)2.92.60.35Anovulatory condition1, %無(wú)排卵表現(xiàn)29.

33、927.10.611Cows with no corpus luteum for at least three consecutive weekly ultrasound examinations after day 50.產(chǎn)后50天后連續(xù)三周B超檢查沒(méi)有黃體的奶牛Average Daily Milk Production of Cows Fed Diets Differing in Phosphorus Content不同磷水平日糧奶牛的平均產(chǎn)奶量不同磷水平日糧奶牛的平均產(chǎn)奶量FIXED NITROGEN FORMS AND PHOSPHORUS ARE PRECIOUS RESOURCES

34、 THAT MUST BE USED WISELY固定氮肥和磷是寶貴的資源,需要好好利用固定氮肥和磷是寶貴的資源,需要好好利用 1 kg fixed nitrogen in fertilizer/manure represents an energy investment equal to the energy in 1.5 liters of diesel fuel. 1 kg 固定氮肥/施入氮肥其能量效果相當(dāng)于 1.5升柴油的能量。 Our planet has abundant phosphorus resources, but there is about a 100 yr suppl

35、y of phosphorus available at manageable cost. 我們的地球有豐富的磷資源,但可利用磷只可供應(yīng)100年的使用。Methane Production and Global Warming甲烷產(chǎn)生與全球變暖甲烷產(chǎn)生與全球變暖 Second only to carbon dioxide in greenhouse effect. 僅次于二氧化碳的第二大溫室效應(yīng)氣體 Approximately 60 times more effective per unit weight than carbon dioxide. 相同質(zhì)量的甲烷對(duì)溫室效應(yīng)的作用相當(dāng)于二氧化碳的

36、60倍。 About 6% of the caloric intake in ruminants is converted to methane. 反芻動(dòng)物攝入的能量有6%轉(zhuǎn)化為甲烷。Concentrations and trends of methane over the last 1000 years. 在過(guò)去的1000年甲烷濃度及發(fā)展趨勢(shì)(Kahlil, 2000)Magnitude of methane fluxes to the lower troposphere from various sources. Whiticar (2000)1各種來(lái)源進(jìn)入大氣對(duì)流層甲烷的數(shù)量Source

37、來(lái)源來(lái)源Flux排放排放% of total emission(Tg CH4 y-1)%占總排放量占總排放量Natural Wetlands 自然濕地自然濕地11521Rice Paddies 稻田稻田11020Domestic Livestock (enteric)家畜(腸)家畜(腸)8115Biomass Burning農(nóng)業(yè)廢棄物燃燒農(nóng)業(yè)廢棄物燃燒5510Natural Gas 天然氣天然氣458Termites 白蟻白蟻407Landfills 垃圾垃圾407Coal Mines 煤礦煤礦356Livestock Manure 家畜糞便家畜糞便142.5Oceans 海洋海洋101.8F

38、resh Water 淡水淡水5.9Hydrates 氫氧化物氫氧化物5.9Total5551/ In “Atmospheric Methane Its Role in the Global Environment.” M. A. K. Khalil, ed.1/ “大氣甲烷在全球環(huán)境中的作用” M. A. K. Khalil, ed.Energy Cost of Food Products Derived From Animals飼料中的能量成本飼料中的能量成本“The modern food industry is in many ways a means of converting fo

39、ssil fuels into edible forms.”ColeyCentre for Energy and the EnvironmentUniversity of Exeter, England“現(xiàn)代農(nóng)業(yè)在很多方面是一種將化石燃料轉(zhuǎn)化為可食用形現(xiàn)代農(nóng)業(yè)在很多方面是一種將化石燃料轉(zhuǎn)化為可食用形式的手段式的手段” Coley ??巳卮髮W(xué)能量與環(huán)境中心埃克塞特大學(xué)能量與環(huán)境中心 ,英格蘭,英格蘭Megajoules of Energy to Produce 1 Megajoule of Food (Coley et al.)1生產(chǎn)生產(chǎn)1兆焦能量的食物消耗的能量兆焦能量的食物消耗的能量Ite

40、m 清單MJ Spent / MJ FoodItem 清單MJ Spent / MJ FoodTomato 西紅柿49Chicken and turkey肉雞7Whitefish 鮭魚36Peas 豌豆 6Green beans 四季豆31Eggs 雞蛋6Cottage cheese 脫脂干酪18Pasta 意大利面食4Apples and pears 蘋果和梨11Rice 大米3Fruit juices 果汁10Potato products 馬鈴薯2Beer 啤酒10Sugar 糖1Beef and veal 牛肉8Bread 面包11/For the average English di

41、et, about six times as much energy invested in food as is present in food. Represents 10% of the national energy budget.1/ 對(duì)于平均英國(guó)食品,投入的能量大約是食品中的六倍,即10%的國(guó)家能量預(yù)算。Cost of Inserting a Member in the Food Chain在食物鏈中增加一個(gè)環(huán)節(jié)的代價(jià)在食物鏈中增加一個(gè)環(huán)節(jié)的代價(jià)Corn Grain (6 units of energy)玉米谷物(玉米谷物(6單位能量)單位能量)Waste Products + H

42、eat (5 units of energy)廢棄產(chǎn)品廢棄產(chǎn)品+產(chǎn)熱(產(chǎn)熱(5單位能量)單位能量)Pig Meat (1 unit of energy)豬肉(豬肉(1單位能量)單位能量)Waste Products + Heat廢棄產(chǎn)品廢棄產(chǎn)品+產(chǎn)熱產(chǎn)熱Human人類人類Returns from Animal Production*Returns on total energy and protein inputsReturns on human-edible energy and protein inputsEnergy (%) Protein (%)Energy (%) Protein (

43、%)Milk151966118Beef443771Swine18304669Poultry12242560*Modified from Bywater and Baldwin (1980). Includes costs of maintaining breeding herds under U.S. production conditions.從動(dòng)物產(chǎn)品的效率從動(dòng)物產(chǎn)品的效率*總能和蛋白利用效率可食用的能量和蛋白能量 (%)蛋白 (%)能量(%)蛋白 (%)牛奶151966118牛肉443771豬肉18304669家禽12242560*對(duì)Bywater and Baldwin (1980)的報(bào)道有所改進(jìn),包括了在美國(guó)生產(chǎn)條件下維持繁殖的成本。SUMMARY總結(jié)總結(jié)1.Emission of ammonia to the atmosphere from livestock operations is one of t

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