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ReproductiveManagementofDairyCattle

奶牛的繁殖管理PaulM.Fricke,PhD保羅?弗里克博士AssociateProfessorDepartmentofDairyScienceUniversityofWisconsin–Madison威斯康星大學(xué)奶業(yè)科學(xué)系-麥迪遜ReproductiveManagementof

DairyReplacements后備牛的繁殖管理Lactation產(chǎn)奶Heifer育成牛Calf犢牛012182430364248Age(months)月齡HeiferDevelopment育成牛的管理Ageat1stCalving=24mo24月齡第一次產(chǎn)犢Birth出生Puberty(9mo)初情期(9月齡)Nonlactating非泌乳期Conception(14mo)受胎14月齡)Ageat1stcalving:24mo24月齡第一次產(chǎn)犢Primiparous初產(chǎn)1stLactation第一次產(chǎn)奶1stCalving第一次產(chǎn)犢2ndCalving第二次產(chǎn)犢M(fèi)ultiparous經(jīng)產(chǎn)2ndLactation第二次產(chǎn)奶Optimalageatcalving=23-24mo理想的產(chǎn)犢年齡=23-24月齡Lactation泌乳育成牛HeiferCalf犢牛012182430364248Age(months)月齡HeiferDevelopment育成牛的管理Ageatfirstcalving=32mo32月齡第一次產(chǎn)犢Birth出生Puberty(9mo)初情期(9月齡)Nonlactating非泌乳期Conception(23mo)受胎(14月齡)Ageat1stcalving:32mo32月齡第一次產(chǎn)犢Primiparous初產(chǎn)1stLactation第一次產(chǎn)奶1stCalving第一次產(chǎn)犢2ndCalving第二次產(chǎn)犢Eachdaycalvingisdelayedbeyond24monthsofagecosts$1.50to$3.00perheifer24月齡后,每拖延一天,育成牛的日飼養(yǎng)為1.5-3美元$360to$720ExtraRearingCostsPerHeifer增加360-720美元的育成牛飼養(yǎng)成本NumberofFemaleYoungStockNeededatVariousHerdCullRatesandAgeat1stCalving

不同淘汰率和第一次產(chǎn)犢月齡不同對青年母牛頭數(shù)的需求CullRate淘汰率(%)Ageatfirstcalving(mo)第一次產(chǎn)奶月齡24262830322453576266702657626772762862677277823066727783883270768288943475818794100367986929910638849198105111408895103110117Lactation泌乳Heifer育成牛Calf犢牛012182430364248Age(months)月齡HeiferDevelopment育成牛的管理Ageat1stCalving=20mo20月齡第一次產(chǎn)犢Birth出生Conception(11mo)受胎(11月齡)Nonlactating非泌乳期Ageat1stcalving:20mo20月齡第一次產(chǎn)犢Primiparous初產(chǎn)1stLactation第一次產(chǎn)奶1stCalving第一次產(chǎn)犢2ndCalving第二次產(chǎn)犢M(fèi)ultiparous經(jīng)產(chǎn)2ndLactation第二次產(chǎn)奶Reducingageatfirstcalvingreducesthenonlactatingperiodbutresultsinimpairedmammarydevelopmentandreductioninsubsequentmilkproduction縮短第一次產(chǎn)犢的年齡會影響乳腺的發(fā)育,繼而減少產(chǎn)奶量CalvingAgeInfluencesSubsequentMilkProduction產(chǎn)犢月齡對產(chǎn)奶量的影響Calvingheifersat23to24moofageisoptimalforfirstlactationmilkyields

23-24月齡產(chǎn)犢,第一胎的產(chǎn)奶量最高Althoughheiferscancalveat19-21moofage,theymayexperiencedystociaandmetabolicdisorders盡管育成??梢栽?9-21月齡產(chǎn)犢,但可能會出現(xiàn)難產(chǎn)和代謝紊亂預(yù)期第一胎產(chǎn)奶量產(chǎn)犢月齡DecidingWhentoBreedHolsteinHeifers

確定育成牛的初配時間BreedingRecommendations初配建議年齡

=13月齡體重

=875磅

(396kg)體高

=50英寸

(127cm)CalvingRecommendations初產(chǎn)建議年齡

=22-24月齡膘情評分=3.0to3.5體重=1250

磅(567kg)post-calving體高

=55英寸(140cm)ReproductiveEfficiency繁殖效率PoorReproduction繁殖差參配率=50%;受胎率=50%:At1stbreeding=14.0Atconception=16.1At1stcalving=25.4GoodReproduction繁殖良好參配率=90%;受胎率=70%AverageAge平均月齡:At1stbreeding=14.0Atconception=14.7At1stcalving=23.9第一次配種受胎第一次產(chǎn)犢第一次配種受胎第一次產(chǎn)犢未受胎受胎時的月齡Lactation泌乳Reproduction繁殖Heifer育成牛Calf012182430364248Age(months)月齡LactationandReproduction

泌乳與繁殖Birth出生1stCalving第一次產(chǎn)犢2ndCalving第二次產(chǎn)犢Nonlactating非泌乳期Primiparous初產(chǎn)1stLactation第一個泌乳期Multiparous經(jīng)產(chǎn)2ndLactation第二個泌乳期兩年(第一次產(chǎn)犢=23-24個月)妊娠(282天)妊娠(282天)空懷空懷人工授精:受胎率<50%人工授精:受胎率<50%受胎率低

14月的產(chǎn)犢間隔初情期

(~9月齡)妊娠(282天)非妊娠期人工授精:受胎率>50%受胎率高人工授精

(13to14月齡)

14月的產(chǎn)犢間隔犢牛MeasuringandMonitoringReproduction

繁殖的指標(biāo)的測定和監(jiān)控TraditionalMeasuresofReproduction

繁殖指標(biāo)的常規(guī)測定CalvingInterval產(chǎn)犢間隔FirstServiceConceptionRate第一次配種受胎率DaysOpen空懷天數(shù)DaystoFirstService產(chǎn)后第一次配種天數(shù)PercentageoftheHerdPregnant牛群懷孕牛百分率ServicesperConception輸精次數(shù)QuestionstoAsk…MetricstoAnswer

問題與答案問:Atwhatrateareeligiblecowsgettingpregnantperunittime?

適配母牛單位時間內(nèi)懷孕的比率?答:

PregnancyRate

懷孕率Question:Howefficientlydocowsconceiveoncetheyarebred?配種后母牛受胎的效率?

Metric:

ConceptionRate受胎率Question:Arewegettingeligiblecowsinseminatedinatimelymanner?對適配母牛及時配種了嗎?Metric:

ServiceRate參配率Question:Isthenumberofcowsgettingpregnantperunittimesufficienttosustaintheherd?單位時間內(nèi)配種懷孕的母牛能夠維持群體數(shù)量嗎?Metric:

PregnancyHardCount懷孕頭數(shù)21-dayPregnancyRisk

21天懷孕是關(guān)鍵Proportionofeligiblecowsthatbecomepregnantevery21days

適配母牛21天懷孕的比率Thisisthekeymeasureofreproduction這是繁殖的關(guān)鍵措施PregnancyRisk懷孕的關(guān)鍵點(diǎn)21-DayPregnancyRisk

21天懷孕關(guān)鍵點(diǎn)ConceptionRiskServiceRiskPregnancyRiskFactorsAffectingtheRateatWhichCowsBecomePregnant:影響母牛懷孕率的因素受胎配種懷孕ConceptionRiskCR=%ofcowsthatbecomepregnantafterabreedingHowefficientlydocowsconceiveoncetheyareserviced?一經(jīng)配種,母牛受胎的幾率?受胎受胎率=受配母牛懷孕的%ConceptionRate,1998MinnesotaDHIData

RapnickiP,StewartS,EickerS.2001.Proc4-StateApplNutrMgtConf,LaCrosse,WI

明尼蘇達(dá)的奶牛受胎率(1998,DHI數(shù)據(jù))受胎率牛群數(shù)ServiceRiskSR=%ofeligiblecowsthatarebredevery21days

參配率=每隔21天適宜母牛接受配種的%SRisequivalenttoheatdetectionrateifcowsarebredtoastandingestrus

依據(jù)站立發(fā)情配種,配種率相當(dāng)于發(fā)情鑒定率Arecowsgettinginseminatedinatimelymanner?母牛是否適時受配?配種HeatDetectionRate,1998MinnesotaDHIData

RapnickiP,StewartS,EickerS.2001.Proc4-StateApplNutrMgtConf,LaCrosse,WI

明尼蘇達(dá)的發(fā)情鑒定率

(1998,DHI數(shù)據(jù))牛群數(shù)發(fā)情鑒定率PregnancyRiskExample1懷孕關(guān)鍵,例一

100%ConceptionRisk;10%ServiceRisk

100%的受胎,10%的受配10nonpregnantcowspastthevoluntarywaitingperiod(i.e.,eligibletobecomepregnant)10頭非妊娠母牛通過了自動等待周期(比如為適配母牛)AIonecowafter21d(i.e.,10%servicerate)21天后一頭母牛輸精(比如為10%的受配率)WhatisthePregnancyRate?懷孕率是多少?PregnancyRiskExample2懷孕關(guān)鍵例二

10%ConceptionRisk;100%ServiceRisk10%的受胎,100%的受配10nonpregnantcowspastthevoluntarywaitingperiod(i.e.,eligibletobecomepregnant)10頭非妊娠母牛通過了自動等待周期(比如為適配母牛)Onecowpregnantafter21d(i.e.,10%conceptionrate)21天后一頭母牛受胎(比如為10%的受胎率WhatisthePregnancyRate?懷孕率是多少?PregnancyRiskExample3

懷孕關(guān)鍵例三

50%ConceptionRisk;80%ServiceRisk

50%的受胎,80%的受配10nonpregnantcowspastthevoluntarywaitingperiod(i.e.,eligibletobecomepregnant)4cowspregnantafter21d21天后4頭母牛懷孕WhatisthePregnancyRisk?哪個是懷孕的關(guān)鍵點(diǎn)?PregnancyRisk,1998MinnesotaDHIData

懷孕的關(guān)鍵點(diǎn)

RapnickiP,StewartS,EickerS.2001.Proc4-StateApplNutrMgtConf,LaCrosse,WI牛群數(shù)懷孕率PregnancyRaten=2,279Mean=14%Median=14%October,2000Compiledby:D.Kelton,K.Lissemore,UniversityofGuelphS.Stewart,UniversityofMinnesota懷孕關(guān)鍵點(diǎn)

(安大略DHI數(shù)據(jù))頻率懷孕平均值中間值頭數(shù)懷孕率PredictedChangesinMilk/CowandExpectedReturn

預(yù)期牛奶/奶牛的變化及期望的回報1unitincreaseinPRoverall~$18avgreturnpercow/year.1unitincreasefrom14%to18%,~$20/cow/yearAssumes:8%PRw/~18,000RHAtostart,Milkispermilkingcow/dayDr.MichaelOvertonUC-DavisVMTRC受胎率受胎率每增加一個單位,每頭牛每年可獲得18美元的回報。受胎率從14%增加到18%,每一個單位可使頭牛每年可獲得20美元的回報。假定8%的受胎率MilkPriceDrivesProfitabilityontheDairy

(Also,ImpactsReturnsFromReproductivePrograms)奶價影響奶牛的效益(對繁殖的回報也產(chǎn)生影響)$23$15Dr.MichaelOvertonUC-DavisVMTRC受胎率預(yù)計不同奶價產(chǎn)生的回報Overview綜述

FactorsAffectingFertilityinLactatingDairyCows

影響泌乳牛繁殖力的因素FemaleFertility母牛的繁殖能力MaleFertility公牛的繁殖能力TimingofAI適時輸精AIEfficiency有效的人工授精XXXAllfourfactorsmustbeoptimizedtoachieveacceptablefertility上述四項(xiàng)達(dá)到最優(yōu),方能取得理想的受胎率FourFactorsInfluenceConceptionRate:影響泌乳牛受胎的四個因素AIEfficiency–semenhandlingandinseminatortechnique掌握人工授精–精液的處理和輸精技術(shù)FemaleFertilityMaleFertilityTimingofAI適時輸精AIEfficiency掌握人工授精XXX公牛的授精力母牛受孕力EffectofstrawnumberandinseminatoronfertilityoflactatingcowsDaltonetal.,2004JDS87:972

輸精次數(shù)和輸精員對泌乳牛受胎的影響150108147110146103150108429596受胎率%輸精次數(shù)專業(yè)輸精本場配種員SemenPlacement精液輸入位置UterineBody子宮體Cervix子宮頸UterineHorn子宮角2002HeiferFieldTrialResults育成牛試驗(yàn)(2002)EffectofInseminator人工授精效果

Riveraetal.,JDairySci87:2051;2004Inseminator輸精123Treatment測試%(no./no.)%(no./no.)%(no./no.)Overall總體24.8a

(28/113)30.0a

(18/60)58.0b

(101/174)a,bWithinarow,percentageswithdifferentsuperscriptsdifferFourFactorsInfluenceConceptionRate:影響受胎率的四個因素FemaleFertility母牛受孕力MaleFertility公牛的授精力TimingofAI適時輸精AIEfficiency掌握人工授精XXXTimingofAI–referstothetimingofinseminationinrelationtobehavioralestrusand/orovulation適時輸精–根據(jù)發(fā)情表現(xiàn)和/或排卵時機(jī)適時輸精BehavioralEstrus發(fā)情表現(xiàn)Between5-30%ofallAIservicestoobservedestrusareconductedatthewrongstageoftheestrouscycle.(Appleyard&Cook,1976;Sengeretal.,1988;Smith,1982)根據(jù)發(fā)情鑒定實(shí)施輸精,錯誤的時機(jī)有5-30%TheAM/PMRuleforTimingAI

適時輸精的上午/下午法則Acowobservedinestrusinthemorning(AM)shouldreceiveAI12hlater(PM)早上發(fā)現(xiàn)發(fā)情,12小時后(下午)輸精Acowobservedinestrusintheafternoonorevening(PM)shouldreceiveAI12hlaterthenextmorning(AM)下午發(fā)現(xiàn)發(fā)情,12小時后(第二天早上)輸精OncedailyAIvs.theAM/PMrule

日輸精一次與上午/下午法的比較Treatment試驗(yàn)#ofcows奶牛頭數(shù)75dNonreturnRate(%)75天不返情率上午/下午法365960.1日輸精一次358160.6Nebeletal.,1994日輸精一次與上午/下午法的比較(0800–0900h)Treatment試驗(yàn)#ofcows奶牛頭數(shù)75dNonreturnRate(%)75天不返情率上午/下午法13262.9日輸精一次12962.0Gonzalezetal.,1985TimeofAIrelativetoadetectedestrus依據(jù)發(fā)情表現(xiàn)適時輸精Nebeletal.,1994間隔(小時)輸精頭數(shù)75天不返情率(%)0-6112659.9a6-12235260.7a12-18245555.5b18-2496253.4bc24-309949.6cFemaleFertilityMaleFertilityTimingofAIAIEfficiencyXXXMaleFertilityincludesallfactorsassociatedwiththebull公牛的授精力包括公牛與公牛有關(guān)的所有因素Naturalservice:bullfertility,libido,heatstress,etc.

本交:公牛的授精力、性欲、熱應(yīng)激等AIisthebestwaytocontrolmalefertility

人工授精是控制公牛授精能力的最好方法FourFactorsInfluenceConceptionRate:影響受胎率的四個因素FemaleFertility母牛受孕力MaleFertility公牛的授精力TimingofAI適時輸精AIEfficiency掌握人工授精ProblemswithNaturalServiceBulls本交的問題

1)Multiplecowsinheat許多奶牛同時發(fā)情

2)Dominanceissues優(yōu)勢問題

3)PregnancyRate受胎率Bullpenvs.AIpenPregRate

本交與人工授精受胎率的比較

(bullPR–AIPR)受胎率%牛群數(shù)FemaleFertilityincludesallfactorsassociatedwiththefemale母牛受孕力包括與母牛相關(guān)的所有因素Includeseverythingnotcoveredbymalefertility,timingofAI,andAIefficiency包括公牛授精能力不涉及的所有因素,適時輸精、和人工授精效率Femalefertilityisthehardestfactorofthefourtocontrol母牛受孕能力是四個因素中最難控制的一個因素FemaleFertilityMaleFertilityTimingofAIAIEfficiencyXXXFourFactorsInfluenceConceptionRate:影響受胎率的四個因素FemaleFertility母牛受孕力MaleFertility公牛的授精力TimingofAI適時輸精AIEfficiency掌握人工授精EnergyEnergyBalanceBodyConditionScore70輸精懷孕

(282天)VWP

(70d)干奶

(60天)010+-54321203040506070WeekofLactation產(chǎn)奶周數(shù)EnergyRequired0EnergyIngestedIncreasingRiskofOVER-FEEDING增加過量采食的危險性EnergyStoredasBodyFatEnergyMobilizedfromBodyFatNegativeEnergyBalanceNadir(signalforfirstovulation)EnergyBalance能量平衡IncreasingRiskofBecomingTOOFAT過肥的危險增加RiskofBecomingTOOTHIN過瘦的危險增加膘情能量平衡能量能量需求能量攝取體脂能量貯存體脂能量代謝能量負(fù)平衡(第一次排卵信號Thin瘦Emaciated

很瘦Average正常Fat肥Obese過肥12345膘情鑒定是表觀評估火牛組織蓄積的方法Def’n:活體脂肪與非脂肪(水、蛋白質(zhì)、灰分)的比率觀察體況變化是判定能量平衡的唯一方法膘情鑒定(膘情評分)RelationshipBetweenDaystoEnergyBalanceNadirandDaystoFirstOvulation第一次排卵和最低能量平衡天數(shù)的關(guān)系

ButlerandCanfield,1989從最低能力平衡回復(fù)過來因牛而異,也是重新恢復(fù)卵巢活動的標(biāo)志

能量平衡后10天第一次排卵第一次排卵天數(shù)最低能量平衡EffectofBodyConditionScoreatTimedAIonFertilityinLactatingHolsteinCows

Sterryetal.,2006

膘情鑒定對荷斯坦泌乳牛適時輸精的影響膘情Item2.5>2.5P

valuePG33(%)39(64/164)55(334/605)0.001PG61(%)36(59/162)50(303/601)0.003Loss(%)d33to615(3/62)8(27/330)0.117MaintenanceofBodyTemperatureinDairyCattle奶牛體溫的維持Homeothermy恒溫:HP+EH=HLHyperthermia高熱:HP+EH>HLEnvironmentalHeat(EH)環(huán)境加熱熱量損失到外界HeatLosstoEnvironment(HL)4種方式:傳導(dǎo)對流輻射蒸發(fā)體內(nèi)產(chǎn)熱InternalHeatProduction(HP)代謝:生長泌乳EffectsofHeatStress熱應(yīng)激的作用Meanrectal平均直腸溫度育成牛接受熱平衡或熱點(diǎn)環(huán)境溫度RectalTemprature直腸溫度嚴(yán)重?zé)釕?yīng)激是可接近華氏107度DatafromPutneyetal.,1989BodyTemperature體溫?zé)崞胶鉄釕?yīng)激時間(小時)直腸溫度Athens,WI雅典、威斯康星

(緯度45°07’;經(jīng)度90°20’)ConceptionRatetoTAIbymonth

月受胎率

(Frickeetal.,2003)受胎率氣溫氣溫受胎率EffectsofHeatStress熱應(yīng)激的作用EffectsonLateFollicularandEarlyEmbryonicDevelopment對于晚期濾泡和早期胚胎的影響Hansenetal.,1992.In:LargeHerdDairyManagement應(yīng)激天數(shù)應(yīng)激排卵桑椹胚Chihuahua,Mexico墨西哥噴淋結(jié)合吹風(fēng)可促進(jìn)蒸發(fā)和對流,為牛體降溫

置于高處每30-40英尺以30度角置放36-48個風(fēng)扇SprinklersandFans噴淋與吹風(fēng)+ANutritionalLinktoPoorReproductivePerformanceinLactatingDairyCows

繁殖性能不良泌乳牛的營養(yǎng)狀況Dr.MiloWiltbankDepartmentofDairyScienceUniversityofWisconsin-Madison威斯康星大學(xué)奶??茖W(xué)系Item項(xiàng)目Cows奶牛Heifers育成牛Estrusduration(h)6.9Conceptionrate(%)<50>50PregnancyLossHighLowMultipleovulation(%)145Twinningrate(%)8~1持續(xù)熱應(yīng)激(小時)受胎率(%)妊娠損失多重排卵(%)雙胎(%)TrendsintheU.S.DairyIndustryoverthelast25yearscanbebestdescribedbytheterm:

過去25年來美國奶業(yè)的發(fā)展趨勢可歸納為-改變

CHANGE問題:Whatprimarycharacteristicallowsalactatingcowtoexhibithighmilkproduction?

泌乳牛高產(chǎn)的主要原因是什么?答:采食量泌乳牛干物質(zhì)的采食量與產(chǎn)奶量強(qiáng)相關(guān)

r=0.88;Harrisonetal.,JDairySci73:2749;1990NovelHypothesis

Dr.MiloWiltbank,UW-MadisonHighFeedIntakeHighMilkProductionVisceralBloodFlowLiverBloodFlowMetabolismofOvarianSteroidsDecreasedCirculatingEstrogen&Progesterone降低雌激素和孕酮的循環(huán)采食量大內(nèi)臟血流量產(chǎn)奶量高肝臟血流量卵巢固醇類代謝ImprovingAIServiceRatesinLactatingDairyCows

改善泌乳奶牛人工授精的受胎率PaulM.Fricke,PhDAssociateProfessorDepartmentofDairyScienceUniversityofWisconsin–Madison威斯康星大學(xué)奶??茖W(xué)系HeatDetectionRate,1998MinnesotaDHIData

RapnickiP,StewartS,EickerS.2001.Proc4-StateApplNutrMgtConf,LaCrosse,WI

發(fā)情鑒定率(明尼蘇達(dá),1998)發(fā)情頭數(shù)發(fā)情鑒定率Whatisthecauseofpoorestrusdetection?發(fā)情鑒定差的原因Estrusbehavior發(fā)情表現(xiàn)Environmentalfactors環(huán)境因素Physiologicfactors生理因素Anovularcows不排卵HeatStress熱應(yīng)激MilkProduction產(chǎn)奶BehavioralEstrusinHolsteinDairyCattleBasedonHeatWatch

觀察到的荷斯坦奶牛的發(fā)情表現(xiàn)LactatingCows泌乳牛NonlactatingHeifers非泌乳育成牛n307114StandingEvents爬跨12.8DurationofEstrus(h)持續(xù)發(fā)情(小時)6.9JDairySci80(Suppl.1):179;1997CircadianDistributionofFirstandLastStandingEventsofEstrus最初和最后站立發(fā)情24小時分布Dransfieldetal.,1998;J.

DairySci.81:1874

開始站立發(fā)情結(jié)束最后站立發(fā)情EstrusExpression-DirtvsConcrete.

發(fā)情表現(xiàn)–土質(zhì)玉水泥場地比較Brittetal.,1986;J.DairySci.69:2195

13OvxlactatingHolsteincowschallengedwithestradiolbenzoateandobserved30minondirtvs.30minonconcrete注射促二醇的13頭奶牛在土質(zhì)運(yùn)動場和水泥運(yùn)動場30分鐘比較Item項(xiàng)目土運(yùn)動場水泥運(yùn)動場No.observations觀察頭數(shù)6969Durationofestrus持續(xù)小時13.8±0.69.4±0.8Totalmounts爬跨總數(shù)7.0±0.63.2±0.3Averagemounts平均爬跨數(shù)3.7±0.32.5±0.2Totalstands站立總數(shù)6.3±0.52.9±0.3Averagestands

平均站立3.8±0.32.7±0.2Allmeansdiffer(P<0.01)betweenlocationsEffectsofHeatStress熱應(yīng)激的影響

SeasonalEffectsonEstrusExpression發(fā)情表現(xiàn)的季節(jié)性影響StandingEvents站立狀況BreedWinter冬季Summer夏季Holstein荷斯坦8.64.5Jersey娟姍12.15.3Nebeletal.,JDairySci80(Suppl1);1997Durationofestrusinrelationtomilkproduction發(fā)情持續(xù)期與產(chǎn)奶量的關(guān)系Lopezetal.,2004;Anim.Reprod.Sci.81:209-223

Analysisincludedallsingleovulations(n=350)exceptfirstpostpartumovulationsAveragemilkproduction

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