1、Brief introduction to the nutrients1第1页，共50页。WaternAccounts for 70%or more of the composition of most plants and animals2第2页，共50页。WateruMost vital nutrient ingestedMay lose 100%of body fat,50%of body protein and liveLose 10%of body water,dehydration occurs and may result in death3第3页，共50页。WateruMost
2、 vital nutrient ingestedTypically consume 2-4 times more water than dry matter intakeFunctionsq Transport of digesta and nutrientsq Excretion of wasteq Lubrication,shaping and cushioningq Substrate（基质）for chemical reactions4第4页，共50页。WateruSourcesDrinking waterMoisture content of feedsq As-fed（实样的）（实
3、样的）feed intakeq Dry matter feed intakeMetabolic water q Water released through chemical reactions at the cell level5第5页，共50页。Metabolic Watern0.6 gram of water produced per gram of carbohydrate metabolizedn0.4 gram of water produced per gram of protein metabolizedn1.0 gram of water produced per gram
4、of fat metabolized6第6页，共50页。WateruDietary needsCattle 10-20 gals/dayHorses10-20 gals/daySheep 1-3 gals/daySwine 1-2 gals/dayPoultry2:1 water:dry feed ratio7第7页，共50页。WateruIntake increased by:Warm to hot temperaturesHigh protein levels High salt levelsHigh fiber levelsHigh dry matter intakes8第8页，共50页
5、。WateruNormal losses:UrineFeces LungsSkin surfaceMilk9第9页，共50页。Water QualitynGood water quality=Less than 0.25%dissolved solidsnCan measurably affect feed consumption and performancenMay reduce palatability or even may be toxic due to levels of heavy metals10第10页，共50页。CarbohydratesuPrimary nutrient
6、component of livestock feedsuStructural and energy reserve of plantsu70-80%of dry matter of plants are carbohydratesuLess than 1%of animal compositionBlood glucoseMuscle glycogen 11第11页，共50页。CarbohydratesnCarbon:Hydrogen:Oxygen=1:2:1 rationClassificationsnMonosaccharides-Glucose,FructosenDisaccharid
7、es-Sucrose,Maltose,LactosenPolysaccharides-Starch,Cellulose12第12页，共50页。CarbohydratesuStarch Non-structural or non-fibrous polysaccharideq Extensively digested q Enzymatic or microbial digestion 13第13页，共50页。CarbohydratesuCellulose Structural or Fibrous polysaccharideq Less digestibleq Requires microb
8、ial digestion 14第14页，共50页。CarbohydratesuFunctions Source of energy for bodily functions Carbon skeletons for building other nutrientsMilk synthesis 15第15页，共50页。ProteinsuPrincipal constituent of organs and soft tissuesuHighest concentration of any nutrient,except water,in all living organisms and ani
9、malsuRequired for life uContain carbon,hydrogen,oxygen and nitrogen 16第16页，共50页。ProteinsuFunctions Structure of organs and soft tissues EnzymesHormonesAntibodiesSkin,HairMilk synthesis 17第17页，共50页。Dietary Essential Amino AcidsuAmino acids required in the diet and cannot be synthesized at a rate suff
10、icient to meet the nutritional requirements of the animal;therefore;must be supplied in the diet 18第18页，共50页。Dietary Essential Amino AcidsuPhenylalanine（苯丙）uValine（缬）uThreonine（苏）uTryptophan（色）uIsoleucine（异亮）u Methionine（蛋）u Histidine（组）u Arginine（精）u Leucine（亮）u Lysine（赖）19第19页，共50页。Dietary Limitin
11、g Amino AciduThe essential amino acid that is present in the lowest quantity in the diet when expressed as a percentage of the animals amino acid requirement 20第20页，共50页。Protein Deficiency uReduced appetite and feed intakeuReduced birth weights and growthuReduced colostrum（初乳）and milk productionuDec
12、reased hormonal productionuDecreased fertility 21第21页，共50页。Excessive Protein Intake uNitrogen deaminateduRemaining carbon skeleton used as energy source or stored as fatuExpensive method of supplying energy to the animal 22第22页，共50页。Non Protein Nitrogen(NPN)uNitrogen supplied to the animal in a non-
13、protein stateUrea or Biuret（缩二脲）uRequires microbial synthesis(Ruminants)uCrude Protein Equivalent%Nitrogen from NPN times a factor of 6.2523第23页，共50页。Lipids(Ether extract)nAre made of carbon,oxygen and hydrogen,butnContain much larger proportions of carbon and hydrogen than carbohydrates do nOrganic
14、 compounds that are characterized by being insoluble in water,but soluble in organic solvents 24第24页，共50页。uConcentrated source of energy1 gram of lipid contains 9.45 kcal of energy as compared to 4.2 kcal of energy for carbohydrates and protein(2.25 times more energy)uSource of dietary fatty acids25
15、第25页，共50页。Lipids uEssential fatty acid=Those fatty acids that an animal requires,but which it cannot synthesize in adequate amounts to meet the animals needLinoleicC18:2LinolenicC18:3ArachidonicC20:4 uMonogastric animals require a minimum of 1%of dietary essential fatty acids in the diet26第26页，共50页。
16、LipidsuFunctions Dietary energy source Source of essential fatty acidsInsulation(隔热、保温）Carrier of fat soluble vitaminsMajor factor in quality grading of beef 27第27页，共50页。LipidsFat deposition in the body:n InternalnIntermuscular（肌间）seam fatnSubcutaneous below skin surfacenIntramuscular（肌内）“marbling”（
17、大理石花纹，肥瘦相间的）28第28页，共50页。LipidsuFeed application Increase caloric density of diet Control dustBind small particlesMaintenance of equipment 29第29页，共50页。MineralsuMajor(macro-elements)CalciumPhosphorusMagnesium PotassiumSodiumChlorineSulfur30第30页，共50页。MineralsuMinor(micro or Trace elements)IronCopperCob
18、altFluorineIodineManganeseSeleniumZinc31第31页，共50页。MineraluFunctions Growth and development of bones,teeth and soft tissues Regulation of cell acid:base balanceComponent of enzymesRegulation of body properties(viscosity（黏稠）,diffusion)32第32页，共50页。MineralsuFeed application Inorganic sourcesSulfates vs.
19、oxidesOrganic sourcesChelates,proteinates or amino acid complexes33第33页，共50页。Minerals Calcium important for skeletal,nerve and muscle functionnDeficiencies increased by nExcess phosphorusnLow levels of Vitamin DnHigh fat levels34第34页，共50页。Minerals Phorphorus important for skeletal,carbohydrate and f
20、at metabolismnMarked influence on reproductionnImportant consideration“Phytate Phosphorus”nForm of phosphorus bound in phytic acid as calcium and magnesium saltsnPrimarily in cereal grainsnLowly available to the non-ruminant35第35页，共50页。Minerals Calcium:Phosphorus Ratio1:1 to 2:1Should never have mor
21、e phosphorus in total diet in relation to calcium36第36页，共50页。Minerals MagnesiumMajor concern:Grass Tetany nLow blood levels of magnesium for cattle grazing cool season foragesnWheat pasture poisoning37第37页，共50页。Minerals SaltWhite Plain salt (NaCl)Red Trace Mineralized SaltYellow Sulfur added nSulfur
22、Important for Methionine synthesisNon-Protein Nitrogen Feeding38第38页，共50页。Trace Minerals ZincMajor concern:Skin Lesions“Parakeratosis”Hoof Problems IronMajor concern:Anemia in young swineCopperMajor concern:Reproduction failure Immune Function39第39页，共50页。Trace Minerals SeleniumMajor concern:Nutritio
23、nal Muscular Dystrophy White Muscle Disease CobaltMajor concern:Vitamin B12 utilizationIodineMajor concern:Heat production and oxidation of nutrients at cell level40第40页，共50页。VitaminsnAre only needed in small amounts nAre essential for life and healthnProvide a defense against disease,promote growth
24、 and reproductionnContribute to the general health of the animal41第41页，共50页。uFat Soluble A VisionD Ca and P absorptionE AntioxidantK Blood coagulation42第42页，共50页。VitaminsuWater Soluble B-ComplexC43第43页，共50页。Energy Nutrients44第44页，共50页。TerminologynCalorie,(cal)-One calorie raises the temperature of 1
25、 g of water 1C(i.e.,14.5 to 15.5 C);nKilocalorie,1,000 calories.nMega calorie,1,000,000 calories.45第45页，共50页。nIUPAC（International Union of Pure and Applied Chemistry 国际理论和应用化学联合会）has adopted the Joule:1 Joule is 107 ergs(0.239 calories),1 kcal=4.184 k Joules46第46页，共50页。TerminologynGross Energy(GE)-t
26、he total amount of heat released when a substance is completely oxidized in a bomb calorimeter.nDigestible Energy(DE)-The gross energy of feed consumed minus the gross energy excreted in the feces.nMetabolizable Energy(ME)-The gross energy of the feed minus the energy in the feces,urine,and gaseous
27、product of digestion.47第47页，共50页。TerminologynHeat Increment(HI)-that portion of the ME which is used for digestion or metabolism of absorbed nutrients into body tissue.nNet Energy,(NE)-the metabolizable energy minus the heat increment.Used for growth,maintenance,production,work,fetal development and
28、 heat production.48第48页，共50页。TerminologynHeat Increment(HI)-that portion of the ME which is used for digestion or metabolism of absorbed nutrients into body tissue.nNet Energy,(NE)-the metabolizable energy minus the heat increment.Used for growth,maintenance,production,work,fetal development and hea
29、t production.49第49页，共50页。Gross Energyin feed consumedFecal energyUrinary energyHeat incrementDigestible energyMetabolizable energyNet energyEnergy Maintenancea.Basal metabolism c.Body heat(warmth)b.involuntary activity d.Heat loss(cooling)Productiona.Tissue growth c.Eggs e.Workb.Reproduction d.Milk(Bomb Calorimetry)(Digestibility)Gaseous Energy1-3%GE50第50页，共50页。
