DigestiveSystems消化系统课件

1、水分无氮浸出物图 概略养分与饲料组成之间的关系 饲料 干物质无机物（粗灰分或矿物质）有机物含氮化合物（粗蛋白质）无氮化合物乙醚浸出物（粗脂肪）碳水化合物粗纤维DigestiveSystems消化系统1水分无氮浸出物图 概略养分与饲料组成之间的关系 饲料 干物质DigestiveSystems消化系统2DigestiveSystems消化系统2四、养分含量的表示方法 某饲料新鲜基础含CP5%，水分75%，求饲料风干基础（含水10%）下含蛋白质多少？ DigestiveSystems消化系统3四、养分含量的表示方法 某饲料新鲜基础含CP5%，水四、养分含量的表示方法 某饲料新鲜基础含CP5%，水分

2、75%，求饲料风干基础（含水10%）下含蛋白质多少？ 设为x，则x90%=5%25%x=（5%90%）25%=18%DigestiveSystems消化系统4四、养分含量的表示方法 某饲料新鲜基础含CP5%，水DIGESTION消化Anatomy and Function of the Gastrointestinal Tract胃肠道解剖和功能DigestiveSystems消化系统5DIGESTION消化Anatomy and FunctioKey concepts about the digestive system and digestionLarge complex molecule

3、s, like proteins, polysaccharides, and triglycerides must be broken down into their simplest part before they are absorbed into the blood or lymph. This is the job of the digestive system 大复杂分子如蛋白质、多糖和甘油三酯在吸收入血或淋巴之前必须分解成最简单成分。这是消化系统的工作。Digestion requires enzymes that break specific types of chemical

4、 bonds. If an enzyme is not present, digestion of that molecule does not occur 消化需要酶。There are two sources of digestive enzymes: those made by the animal (digest soluble CHO, protein and lipids) and those made by microbes during fermentation (digest soluble CHO, protein and lipids and fiber). 消化酶有两个

5、来源： 一是来自动物本身（消化可溶性碳水化合物、蛋白质和脂类）； 二是来自于微生物（消化可溶性碳水化合物、蛋白质和脂类及纤维）DigestiveSystems消化系统6Key concepts about the digestiKey concepts about the digestive system and digestionFor optimum utilization, digestion or fermentation needs to occur either in front of, or inside the part of digestive system that abs

6、orbs the final products produced by digestion 为优化利用，消化或发酵需要发生在消化系统吸收消化产物之前或当中。Fermentation improves overall utilization of feeds for all animals 发酵改善所有动物饲料充分利用。Differences in size of some parts of the digestive system and location of fermentation within the digestive system dictate the types of feed

7、s animals can utilize and the proper means of feeding. 由于消化系统尺寸大小不同或发酵位置不同决定动物能利用饲料的类型及适宜的饲喂方法。为什么胃没有被消化了！DigestiveSystems消化系统7Key concepts about the digestiGastrointestinal TractComplex physiologically and anatomicallyExtends from mouth to anusFunctionsDigestionAbsorptionProtect body from:Remove un

8、digested material and wastesImmunological functionMetabolismEndocrine functions (Hormones)Site of fermentation (symbiosis)DigestiveSystems消化系统8Gastrointestinal TractComplex 咽盲肠十二指肠肝脏胆囊唾液腺舌牙齿幽门括约肌胃食道唾液腺肛门阑尾会厌胰腺大肠小肠直肠DigestiveSystems消化系统9咽盲肠十二指肠肝脏胆囊唾液腺舌牙齿幽门括约肌胃食道唾液腺肛门RuminantCattle, Sheep, Goats反刍动物-牛

9、，绵羊，山羊Nonruminants 非反刍动物网胃小结肠盲肠小肠牙齿食道胃大结肠食道瘤胃皱胃小肠直肠胃小肠小肠食道肝脏盲肠结肠瓣胃DigestiveSystems消化系统10RuminantCattle, Sheep, GoatsNSimplified Digestive SystemsDigestiveSystems消化系统11Simplified Digestive SystemsDiDigestiveSystems消化系统12DigestiveSystems消化系统12Mouth and Saliva嘴和唾液Function of the mouth 嘴的功能Take in food

10、采食Prehensile structureHorses-lips 马-唇Cattle-tongue 牛-牙齿Pigs-lips 猪-唇Sheep-lips 绵羊-唇Taste accept or reject food 品尝Chewing 嚼Reduces particle size which improves digestibilityStimulates saliva flowMix digesta with saliva 混合DigestiveSystems消化系统13Mouth and Saliva嘴和唾液Function oPig猪Horse马Sheep绵羊Cattle牛臼齿切割

11、和犬齿牙床DigestiveSystems消化系统14Pig猪Horse马Sheep绵羊Cattle牛臼齿切割和犬DigestiveSystems消化系统15DigestiveSystems消化系统15Grinding grain to reduce particle size锤片转子出料口磨的档板 DigestiveSystems消化系统16Grinding grain to reduce partiMouth and SalivaFunction of saliva唾液的功能Lubricate food to allow swallowing and mixing of food in s

12、tomach of nonruminants润滑食物便于吞咽和食物在反刍动物胃里混合Initiate enzymatic digestion (amylase) of starch开始淀粉酶解（淀粉酶）Produce buffer to counteract acid in stomach产生缓冲液中和胃酸DigestiveSystems消化系统17Mouth and SalivaFunction of saMouth and SalivaComposition of saliva 唾液成分Water水Inorganic components无机成分Used to supply mineral

13、s to digesta andbuffers to regulate pHOrganic components有机成分Needed for digestive functionsUreaEnzymesMucoproteins黏蛋白DigestiveSystems消化系统18Mouth and SalivaComposition ofEsophagus食道Muscular tube肌管Extends from pharynx to cardia of stomach 咽至贲门Striated muscle 纹状肌which changes to smooth muscle平滑肌Esophagu

14、s of dogs and ruminants have striated muscle throughoutDigestiveSystems消化系统19Esophagus食道Muscular tube肌管DigeEsophagusExtended by reticular groove (esophageal groove) in young ruminantsAllows passage of milk from esophagus directly into omasum during nursing奶至皱胃This prevents milk from entering the rum

15、en, where it would be fermented resulting in a loss of nutrients 防止奶流入瘤胃DigestiveSystems消化系统20EsophagusExtended by reticularStomach胃(Glandular or True) Stomach腺胃或真胃Functions of true stomach真胃的功能Mixing of food 混合Hold food for gradual release into small intestine食物进入小肠Production of HCl and pepsinogen盐

16、酸和胃蛋白酶原Absorption of alcohol, aspirin, volatile fatty acids (ruminants), and various other compounds. 吸收乙醇、阿司匹林、挥发性脂肪酸和其它不同化合物。There is no absorption of monosaccharides, amino acids, or long chain fatty acids in the stomach. 胃不吸收单糖、氨基酸或者长脂肪酸链。DigestiveSystems消化系统21Stomach胃(Glandular or True) StStoma

17、chSecretions of true stomach真胃分泌作用HClDenatures protein-breaks intermolecular bondsKills most bacteria present in foodstuffsActivates pepsinogenRuptures starch granules破裂淀粉颗粒Pepsinogen胃蛋白酶原HCl converts pepsinogen to pepsin the active enzyme胃蛋白酶原 胃蛋白酶Pepsin begins digestion of proteinsClots milk 合牛奶牛凝

18、结成块DigestiveSystems消化系统22StomachSecretions of true stomRegions of true stomach真胃的区域Esophageal region食道Nonglandular 无腺体Area most prone to ulcers溃疡Cardiac region喷门Produces mucus, which protects stomach lining产生黏液保护胃内层Fundic region胃底Produces mucus, enzyme, HClParietal cells-produce HClChief cells-produ

19、ce pepsinogenPyloric region幽门贲门腺体区域胃底腺体区域憩室外部表面幽门食道腺体区域胃切面边缘憩室外部表面幽门腺体区域DigestiveSystems消化系统23Regions of true stomach真胃的区域贲门Normal Esophogeal Area of Pig Stomach猪胃正常的食道Stomach Ulcer in a Human人的胃溃疡DigestiveSystems消化系统24Normal Esophogeal AreaStomach StomachSecretions of true stomach真胃分泌作用Rennin (abom

20、asum)凝乳酶Clots milkMucus黏液Protects lining of stomach from acid and pepsinDigestiveSystems消化系统25StomachDigestiveSystems消化系统25Ruminant Stomach反刍动物的胃网胃瓣胃食道瘤胃皱胃小肠瘤胃皱胃网胃气体液体瓣胃DigestiveSystems消化系统26Ruminant Stomach反刍动物的胃网胃瓣胃食道瘤DigestiveSystems消化系统27DigestiveSystems消化系统27Ruminant StomachRumen 瘤胃DevelopmentI

21、n newborn ruminants the abomasum is the only fully developed part of the stomach.新生反刍动物皱胃充分发育The rumen, reticulum and omasum are present, but they are very small and nonfunction.其它胃小而无功能。DigestiveSystems消化系统28Ruminant StomachDigestiveSysteRuminant StomachConsumption of forages and concentrates and i

22、noculation with rumen bacteria from other ruminants begins fermentation in rumen which caused the rumen to develop. 粗饲料和精饲料消耗和接种瘤胃细菌开始在瘤胃中发酵，引起瘤胃发育。On average, it takes about 2 3 months in calves and lambs for the rumen to develop. 犊牛和羔羊大约2-3个月瘤胃发育期。DigestiveSystems消化系统29Ruminant StomachDigestiveSys

23、teRelative Size of Stomach Compartments胃分隔相对尺寸Cattle牛, %Sheep绵羊, %Rumen瘤胃54 (1)62 (1)Reticulum网胃7 (4)11 (3)Omasum瓣胃26 (2)5 (4)Abomasum皱胃13 (3)22 (2)DigestiveSystems消化系统30Relative Size of Stomach CompaFunction and Gross Appearance of Stomach CompartmentsPrimary FunctionDistinctive Internal StructureR

24、umen瘤胃Fermentation; absorption of VFA, NH3, waterPapillae; 乳头looks like shag carpet粗毛毯Reticulum网胃Fermentation发酵Honeycomb appearance蜂巢Omasum、瓣胃Reduce particle size, absorb H2O“Leaves” or many piles looks like a book on edgeAbomasum皱胃Functions of “true” stomachNone shiny with mucusDigestiveSystems消化系统

25、31Function and Gross Appearance Papillae of the RumenDigestiveSystems消化系统32Papillae of the RumenDigestiveReticulum (Honeycomb)网胃DigestiveSystems消化系统33Reticulum (Honeycomb)网胃DigestiOmasum (Butchers Bible)瓣胃DigestiveSystems消化系统34Omasum (Butchers Bible)瓣胃DigesDigestiveSystems消化系统35DigestiveSystems消化系统3

26、5Fermentation in Rumen and Reticulum瘤胃和网胃中发酵The rumen contains:25 50 x 109 bacteria/ml细菌25 50 x 104 protozoa/ml 原生动物Yeast and fungi also present but in much lower concentrations酵母和真菌淀粉颗粒细菌原虫细菌DigestiveSystems消化系统36Fermentation in Rumen and RetFermentation in Rumen and Reticulum瘤胃和网胃中发酵Anaerobic micr

27、obial digestion of feedstuffs into volatile fatty acids, methane, carbon dioxide, and heat.饲料厌氧微生物发酵生成挥发性脂肪酸、甲烷、二氧化碳和热量。Microbes synthesize all amino acids, all B vitamins and vitamin K.微生物合成所有氨基酸和所有B族维生素和维生素K。Most unsaturated fatty acids entering the rumen are saturated by the microbes. 绝大多数不饱和脂肪酸生

28、成饱和。DigestiveSystems消化系统37Fermentation in Rumen and RetiRumination (Chewing the Cud)反刍Process by which ruminants rechew the coarse fibrous part of the diet.饲粮中粗纤维部分Parts of rumination are:Regurgitation Remastication Reensalivation ReswallowingDigestiveSystems消化系统38Rumination (Chewing the Cud)反Rumina

29、tion (Chewing the Cud)Rechewing reduces particle size and stimulates saliva flow 反复嚼咀降低颗粒尺寸和刺激唾液流动。Diets low in forage result in reduced rumination which causes reduced saliva flow and less buffer entering the rumen 低粗饲料Ruminants spend 610 hours/day ruminating DigestiveSystems消化系统39Rumination (Chewi

30、ng the Cud)DBloat膨胀Accumulation of fermentation gas in rumen that is not belched. 发酵气体积聚，没有排出去DigestiveSystems消化系统40Bloat膨胀Accumulation of fermentBloatDigestiveSystems消化系统41BloatDigestiveSystems消化系统41EructationExpelling of gas produced from microbial fermentationDuring peak fermentation 12-30 liters

31、 of gas are produced each hourDigestiveSystems消化系统42EructationDigestiveSystems消化系统Small Intestine小肠Divided into three segments:Duodenum十二指肠Attached to true stomach, pancreatic and bile ducts enter near the beginning of the duodenumJejunum空肠Middle segmentIleum回肠Last segment, ends in ileo-cecal valve

32、which regulated flow of digesta into the large intestineDigestiveSystems消化系统43Small Intestine小肠Divided into Small IntestinePrimary site for digestion of proteins, non-fibrous carbohydrates, and lipids. 蛋白质、非纤维型碳水化合物和脂类。The only site for absorption of amino acids, monosaccharides and long chain fatty

33、 acids. 吸收氨基酸、单糖和长链脂肪酸的唯一位置。All vitamins and minerals can be absorbed in the small intestine. 所有维生素和矿物质能被吸收到小肠中。DigestiveSystems消化系统44Small IntestinePrimary site foSmall IntestineLarge amount of surface area in small intestine is due to folds in the wall, presence of villi, and especially microvilli

34、 绒毛The surface of the villi are covered withenterocyte cells which contain microvilli. Absorption occurs when compounds pass through the microvilli, enter the enterocyte, and are transferred to either the blood or lymph淋巴.DigestiveSystems消化系统45Small IntestineLarge amount ofDigestiveSystems消化系统46DigestiveSystems消化系统46VilliMicrovilli (Brush border)DigestiveSystems消化系统47VilliMicrovilli (Brush border)Pancreas胰腺Enzymes and buffer from the pancreas enter into the small intestine via the pancreatic duct.Cell Types:Acinar CellsSecrete enzymesCentroacin