奶牛的乳房炎

MastitisinDairyCattle奶牛的乳房炎美国谷物协会供稿马春生翻译NormalMilk正常的牛奶Color–white,oryellow-white颜色－白色或淡黄色Novisibleclotsorflakes没有可见的凝块或絮片SomaticCellCount(SCC)100,000perml体细胞数计数每毫升小于10万MastitisMilk乳房炎奶Abnormalcolor颜色不正常Visibleflakesorclots有可见的凝块或絮片SCCalmostalways200,000/ml体细胞计数总是大于每毫升20万SCCfrom100,000to200,000isquestionable(chronicmastitisorrecoveringfrommastitis)体细胞计数10万-20万为可疑（慢性乳房炎或正在从乳房炎痊愈）SomaticCellCount(SCC)体细胞计数Somaticcellsarecellsfoundinmilkandaremostlywhitebloodcellswithsomemammaryepithelialcells体细胞是在牛奶中发现的细胞。大多数为白血球，带有一些乳腺上皮细胞。Mostcommoncellinmastitismilkistheneutrophil乳房炎奶中最普遍的细胞是嗜中性白细胞。SomaticCellCountandLossinProduction体细胞计数与产奶量的损失SomaticCellCountLinearScoreEstimatedDailyLossofMilkProduction(kg)体细胞计数线性评分估计每日产奶量的损失（千克）12,5000025,0001050,00020100,00030.68200,00041.36400,00052.04800,00062.721,600,00073.413,200,00084.096,400,00094.77RelationshipofSCCandProduction体细胞计数与产奶量的关系Above50,000cells/mlthereisalossofproductionof0.68kgperdayforeachunitofincreaseinthelinearscore.OreachdoublingoftheSCC每毫升体细胞超过5万时，线性评分每增加一个单位每日产奶量就损失0.68千克。或每个分值使体细胞计数增加一倍。Ex…from200,000to400,000cellspermlthedailylossincreasesfrom1.36to2.04kg例如，体细胞计数每毫升从20万增加到40万，产奶量每头日损失就从1.36千克增加到2.04千克。InterpretingSCC体细胞的解释Normalmilk(0-100,000/ml)thereisessentiallyzerolossofproduction正常牛奶（每毫升0－10万）的产奶量损失为零。Mastitismilk(200,000/ml)thereisatleast1.3kgofproductionlossdailypercow乳房炎奶（每毫升体细胞大于20万）头日产奶量至少损失1.3千克。SCCGoalsforDairyHerds(perml)奶牛群每毫升体细胞的目标BulkTankSCC250,000罐乳小于25万HerdAverage200,000(averageofindividualcowtests)群体平均小于20万（个体母牛测定的平均数）1stLactationCows(atcalving)100,000一胎母牛（产犊时）小于10万85%ofallcows200,000全部母牛85%以上小于20万95%ofallcows500,000全部母牛95%以上小于50万ClassificationofMastitis乳房炎的分类Transmission:ContagiousorEnvironmental传播：传染性或环境性Disease:ClinicalorSub-clinical发病：临床或亚临床Diseaseduration:AcuteorChronic发病的持续时间：急性或慢性Transmission:Contagious传播：接触性传染Contagiousmastitis:spreadfromcowtocowthroughmilkingmachines,handsofmilkers,andotherformsofcontactbetweencows传染性乳房炎：母牛之间通过挤奶机、挤奶员的手或母牛之间的其它接触形式来传染。Examples:Streptococcusagalactiae,举例：无乳链球菌Staphylococcusaureus,andMycoplasma金黄色葡萄球菌，支原体（菌）Transmission:Environmental传播：环境性的EnvironmentalMastitis:Theorganismispresentintheenvironment–bedding,manure,cowskinsurface,milkingequipment,andmilker’shands环境性乳房炎：这种微生物存在于环境中－褥草、粪便、母牛的表皮、挤奶设备和挤奶员的双手。Examples:Streptococcusuberus,otherStrepnon-agalactiae,coagulasenegativestaph,coliforms,actinomycespyogenes,etc..例如：乳房链球菌、其他的非无乳链球菌、凝固酶阴性葡萄球菌、大肠杆菌、放线化脓菌等。ClinicalandSub-clinical临床和亚临床ClinicalMastitis:Traditionalclassification–visibleclotsandflakes临床乳房炎：传统分类－有可见的凝块和絮片。Sub-clinical:OnlyevidenceishighSCC,orpositivebacterialcultureofmastitisorganism亚临床：只是体细胞计数明显地高，或乳房炎微生物的细菌培养呈阳性。DiseaseOnsetandDuration疾病的发作和持续时间Acute(orperacute):cowsmayappearsick,mayhaveafever,uddermaybefirmandswollen.Mostseverecasesareoftencausedbycoliforms急性（或亚急性）：母牛可能出现病态、发烧、乳房变硬并肿胀。严重病例通常是由大肠杆菌引起。Chronic:persistentbacterialinfection,recursatintervals,highSCC,normalmilkbetweenepisodes.Thisisthemostseriousimpactoncowproduction慢性：细菌持续感染，间歇性发病，体细胞计数高。两次发病之间牛奶正常。这种情况对母牛的产奶量影响最严重。MastitisDetectionMethods乳房炎的检测方法Stripcuporpre-milkingexam挤奶前把头2-3把奶挤到奶样杯内检查CaliforniaMastitisTest(CMT)加利福尼亚乳房炎测定法WisconsinMastitisTest(WMT)威斯康辛乳房炎测定法ElectronicSCC(Fossequipment)电子体细胞计数（福斯设备）DirectMicroscopicSCC直接显微镜体细胞计数法CultureofBulkTankMilk罐乳的细菌培养IndividualCowBacterialCulture个体母牛细菌培养StripCuporPre-MilkingExam挤奶前把头2-3把奶挤到杯内检查Examofeachquarterinacuporonthefloorofthemilkparlor把每个乳区的牛奶挤到奶样杯内或挤到挤奶厅地面上检查。Beawareofhygiene注意卫生问题。Thisisfordetectionofclinicalmastitisonly这种方法只是检查临床乳房炎。CaliforniaMastitisTest(CMT)加利福尼亚乳房炎测定法CMT–simple,cheap,fasttestforapproximateSCClevelCMT-能很快地测定出体细胞计数的近似值，简便、成本低。Candoindividualquartersormixedsamplefromonecow可对单个乳区或每头母牛的混合奶样进行测定。TestisbasedonareactionofthechemicalreagentwithDNAofsomaticcells测定原理是建立在化学试剂与体细胞DNA混合后的反应基础上的。ScoringtheCMTCMT的判定评分Samplesaretakenfromeachquarterinthespecialpaddle把每个乳区的牛奶样品挤到专用的检测盘内。Reagentisaddedinequalvolumes(about2mlofmilkand2mlofCMTreagent)加入等量的试剂（约2毫升牛奶和2毫升CMT试剂）。Thepaddleisswirledfor10secondsandexamined摇动检测盘约10秒后检查。CMT检测盘CMTScoresCMT的判定评分N(negative)–nothickeningofliquid,veryhomogenousN（阴性）－液体不粘稠，质地很均匀。T(trace)–slightthickeninginitially,butmaydisappearafter10secondsT（可疑）－开始摇动时有点变稠，但10秒后可能消失。1(WeakPositive)–obviousthickening,butnoformationofgel,thickeningmaydisappearafter20seconds1（弱阳性）－明显变稠，但没有形成凝胶，20秒后变稠情况可能消失。CMTScoresCMT的判定评分2(DistinctPositive)–Milkthickensimmediately,gelformationisvisible,mixturestillmaintainslevelsurface2（明显阳性）-牛奶立即变稠，形成可见的凝胶，混合物仍然维持水平的表面。3(StrongPositive)–Thickgelformation,geldoesnotlevelout,clumpspresent3（强阳性）-形成粘稠的凝胶，凝胶凸起并出现凝块InterpretingCMTResultsCMT判定结果的解释CMTScore判定评分SCC(cells/ml)体细胞计数N阴性0–200,000T可疑200,000–400,0001弱阳性400,000–1,200,0002明显阳性1,200,000–5,000,0003强阳性5,000,000InterpretingCMTScoresCMT判定评分的解释Herdproblemexistsif15%ofcowshavescoresof2or3如果15％以上的母牛CMT评分为2或3，则该群存在乳房炎问题。CowswithconsistentlyhighSCC(2or3)shouldbeconsideredcullcandidates应考虑淘汰体细胞计数长期居高不下（2或3）的母牛。Cullingdecisionshouldalsoconsiderproductionlevelsandresultso