2024年9月25日发(作者：禚暮)
TheilerStage1-One-cellegg
Fertilizedone-cellstageegg(embryo),zona
pellucidapresent(showninred).
0-0.9dpc(range0-2.5)
Scalebarinmicrons
TheilerStage2-Dividingegg
Dividingeggstage,zonapellucidapresent(shown
inred).Firstcleavageoccursatabout24hours.
1dpc(range1-2.5)
2-4cells.
Scalebarinmicrons
TheilerStage3-Morula
Four-to16-cellstageembryosfromearlytofully
llucidapresent(shownin
red).Embryosintheoviducttowardsutero-tubal
junction.
2dpc(range1-3.5)
4-16cells.
Allscalebarsinmicrons.
TheilerStage4-Blastocyst(ICMapparent)
Embryoprogressesfrommorulatotheblastocyst
stillwithinthezonapellucida(showninred).Thereis
earlyevidenceoftheblastocoeliccavity.
3dpc(range2-4)
16-40compactedcells.
Allscalebarsinmicrons.
Intheblastocyststage(zona-intact)thereisa
distinctinnercellmassandanouterlayerof
ylocatedintheuterine
lumen.
TheilerStage5-Blastocyst(zona-free)
Blastocyst(zona-free),invariablylocatedwithin
theuterinelumen.
4dpc(range3-5.5)
Scalebarinmicrons
TheilerStage6-Attachmentofblastocyst
Blastocystsimplants,firstevidenceof
embryonicendodermcellscovering
theblastceolicsurfaceoftheinnercell
mass.
4.5dpc(range4-5.5)
WitschiStage8(rat)
CarnegieStage4(human)
Scalebar
TheilerStage7-ImplantationandformationofEgg
Cylinder
ncrease
inthenumberofinnercellmasscells
leadingtotheformationoftheepiblastwith
subsequentgrowthtoformtheegg
ximalorvisceralcells
(oppositesidefromthetrophoblasticcap)
yendoderm
linesthemuraltrophectoderm.
5dpc(range4.5-6)
WitschiStage10(rat)
CarnegieStage5(human)
Scale
TheilerStage8-Differentiationofeggcylinder
ernaltissueis
invadedbytrophoblast(primary)giantcellsand
theectoplacentalconeisinvadedbymaternal
entiationoftheeggcylinderinto
embryonicandextraembryonicregionsandthe
rt's
membrane,whichisnon-cellularandsecretedby
thedistalendodermfirstappears.
6dpc(range5-6.5)
WitschiStage10-11(rat)
CarnegieStage5(human)
Scalebarinmicrons
TheilerStage9-AdvancedEndometrialReaction
PS:Advancedegg-cylinderstagewiththefirst
sclear
morphologicaldistinctionbetweentheembryonic
oplacental
coneisfurtherinvadedbymaternalbloodandthe
originallumenoftheuterinecrypthas
disappeared.
ES:Lateinthisstagegastrulationbegins,
producingthefirstmesodermalcells.
6.5dpc(range6.25-7.25)
Downs&DaviesPS-ES:prestreaktoearly
streak
WitschiStage11(rat)
CarnegieStage6-7(human-stagetable)
Scalebarinmicrons.
TheilerStage10-Amnion
Gastrulationcontinuesthroughoutall
sub-divisionsofthisstageand:
MS:Tissueattheposteriorendoftheprimitive
streakbulgesintotheproamnioticcavityand
formstheposterioramnioticfold.
LSOB:Inthemesodermoftheposterioramniotic
foldsmallcavitiescoalescetoformasinglecavity,
theexocoelom.
LSEB:Theallantoicbudfirstappears,gastrulation
continuesandthenodebecomesvisible.
7dpc(range6.5-7.5)
Downs&DaviesMS-LSmidstreaktolate
streak
WitschiStage12(rat)
CarnegieStage8(human-stagetable)
Scalebarinmicrons.
TheilerStage11-NeuralPlate,PresomiteStage
NP:Theamnioticcavityissealedoffwithnow
threecavities-amniotic,exocoelomand
ralplateisdefined
themidline,sub-adjacenttotheneuralgroove,
thenotochodalplateisvisible.
LNP:Theallantoicbudelongates.
EHF:Therostraloftheneuralplatebeginsto
enlargetoformtheheadfolds.
LHF:Headfoldscontinuetoenlargeandthe
foregutpocketbeginstoform.
7.5dpc(range(7.25-8)
Downs&DaviesOB-EB/LB-EHF-LHF:-noAll.
arlyheadfoldtolatehead
fold
WitschiStage12-13(rat)
CarnegieStage9(human-stagetable)
Scalebarinmicrons.
TheilerStage12-Firstsomites
Unturnedembryowithfirstappearence
ofsomitepairs.
1-4somites:Theallantoisextends
furtherintotheexocoelomandthe
maxiliarycomponentsofthe1st
preoticsulcusisvisibleinthe2-3
diogenicplate
beginstoformandtheforegutpocketis
clearlyvisible.
5-7:Theheadfoldsareparticularly
prominentandneuralclosureoccursin
theregionofthe4thand5thsomites,
extendinginbothdirectionsfromthis
icplacodesarefirstevident
andbecomeindentedtoformtheoptic
rtrudimentdevelops
antoiscontactsthe
chorionattheendofthisstage.
Absent:The2ndbranchialarchand>7
somites.
8dpc(range7.5-8.75)
1-7somitepairs
WitschiStage14-15(rat)
CarnegieStage9(human-stagetable)
Allscalebarsinmicrons
Clickonanimageforalargerversion
TheilerStage13-Turningoftheembryo
Thisisashortperiodwithturninginitiatedin
embryoswith6-8pairsofsomitesandusually
completedinembryoswith14-16pairsof
stbranchialarchhas
maxillaryandmandibularcomponentsbut
themaxillaryprocessisnotvisibleuntillater
(TS16).Asecondbranchialarchisnow
sevidenceofregionalisation
oftheheartandtheneuraltubeisclosed
fromapointoppositetheoutflowtracttothe
proximalpartofthetail.
Absent:3rdbranchialarch.
8.5dpc(range8-9.25)
8-12somitepairs
WitschiStage15(rat)
CarnegieStage10(human-stagetable)
Allscalebarsinmicrons.
Clickonanimageforalargerversion.
TheilerStage14-Formationandclosureofanterior
neuropore
Therostralextremityoftheneuraltubeclosesin
embryoswithusuallyabout15-18somitepairs
cpitbecomes
progressivelymoreindentedbutnotclosed,the
mandibularprocessofthe1stbranchialarchis
3rdbranchialarchbecomes
easingly
prominentridgeonthelateralbodywall,
approximatelyatthelevelofthe8th-12thsomite,
indicatesthesiteofthefutureforelimbbud.
Absent:forelimbbud.
9dpc(range8.5-9.75)
13-20somitepairs
WitschiStage16(rat)
CarnegieStage11(human-stagetable)
Allscalebarsinmicrons.
Clickonanimageforalargerversion.
TheilerStage15-Formationofposteriorneuropore;
forelimbbud
Theposteriorneuroporeformandthe
condensationoftheforelimbbudbecomes
apparentnearthe8th-12thsomitepairs.
Adistinctcondensationofthehindlimb
budappearsjustattheendofthestage.
Theforebrainvesiclesubdividesinto
telencephalicanddiencephalicvesicles.
Absent:hindlimbbud,Rathke'spouch.
9.5dpc(range9-10.25)
21-29somitepairs
WitschiStage17-19(rat)
CarnegieStage12(human-stagetable)
Allscale
bars
inmicrons.
Clickonanimageforalargerversion
TheilerStage16-Closureofposteriorneuropore;hind
limbbudandtailbud
Thehindlimbbudbecomesvisibleat
tailbudappearsasashortstumpand
the3rdand4thbranchialarchesare
'spouchand
endofthisstagetheposterior
neuroporebeginstoclose.
Absent:thinandlongtail.
10dpc(range9.5-10.75)
30-34somitepairs
WitschiStage20-21(rat)
CarnegieStage13(atlas),14(atlas),
15(atlas)(human-stagetable)
Allscale
bars
inmicrons.
Clickonanimageforalargerversion.
TheilerStage17-Deeplensindentation
Themostobviousdistinguishing
featuresarethedeepeningofthelens
pit,withanarrowingofit'souter
pore-likeopening,andthefirst
appearenceofthephysiological
1stbranchial
archisconspicuouslydividedintoit
maxillaryandmandibular
sadvanced
developmentofthebraintubeandthe
tailelongatesandthins.
Absent:nasalpits.
10.5dpc(range10-11.25)
35-39somitepairs
WitschiStage24-25(rat)
CarnegieStage13(atlas),14(atlas),
15(atlas)(human-stagetable)
Allscalebarsinmicrons.
Clickonanimageforalargerversion.
TheilerStage18-Closureoflensvesicle
Theprimaryexternallyrecognisablefeatureis
somitesinthecervicalregionarenolonger
visibleandtherapidgrowthofthebrainis
alpitsstarttoform.
Absent:auditoryhillocks,anteriorfootplate.
11dpc(range10.5-11.25)
40-44somitepairs
WitschiStage25-26(rat)
CarnegieStage13(atlas),14(atlas),15
(atlas)(human-stagetable)
Allscalebarsinmicrons.
Clickonanimageforalargerversion
TheilerStage19-Lensvesiclecompletelyseparated
fromsurface
Thelensvesiclebecomescompletelyclosedand
ipheral
forelimbsareseentobedividedintotworegions,
theproximalpartconsistingofthefuture
limb-girdleandarmandthemoreperipheralpart
whichformsacircularorpaddle-shaped
handplate(anteriorfootplate).Themedialand
lateralmarginsoftheoticpitarecomingtogether
reducingtheentrancetoanarrowslitandthe
auditoryhillocksbecomevisible.
Absent:retinalpigmentation,signsoffingers.
11.5dpc(range11-12.25)
45-47somitepairs
WitschiStage26-27(rat)
CarnegieStage16(atlas),(human-stagetable)
Allscalebarsinmicrons.
Clickonanimageforalargerversion.
TheilerStage20-Earliestsignsof
fingers
PreviousStageStageIndexStageCriteriaAnatomyNextStage
Thehandplate(anteriorfootplate)isnolonger
circularbutdevelopsangleswhichcorrespond
teriorfootplateis
alsodistinguishablefromthelowerpartofthe
ssibletoseethepigmentationofthe
pigmentedlayeroftheretinathroughthe
gueandbrain
vesiclesareclearlyvisible.
Absent:5rowsofwhiskers,indentedhandplate.
12dpc(range11.5-13)
48-51somitepairs
WitschiStage28(rat)
CarnegieStage17(atlas),(human-stage
table)
Allscalebarsinmicrons.
Clickonanimageforalargerversion
TheEdinburghMouseAtlas:
TheilerStage21-Anteriorfootplateindented
PreviousStageStageIndexStageCriteriaAnatomyNextStage
Thedistalbordersoftheanteriorandposterior
footplatesarenowindentedandthedigitwidths
owand
narapidly
developsandformsacrestatrightanglestothe
wsofvibrissaearevisibleaswellas
aprominanthairfollicleovertheeyeandanother
svesiclehaslostit'slumen.
Thephysiologicalumbilicalherniaisprominent.
Absent:hairfollicles,distallyseparatefingers.
13dpc(range12.5-14)
52-55somitepairs
WitschiStage29-30(rat)
CarnegieStage18(atlas),19(atlas),(human-
stagetable)
Allscalebarsinmicrons.
Clickonanimageforalargerversion.
TheEdinburghMouseAtlas:
TheilerStage22-Fingersseparate
distally
PreviousStageStageIndexStageCriteriaAnatomyNextStage
Individualfingersarevisibleintheanterior
footplateandtherearedeepindentations
betweenthetoeswhicharenotyetseparated.
Thelongbonesofthelimbsarepresentand
therearehairfolliclesinthepectoral,pelvicand
naisturnedforwardsand
theumbilicalherniaisconspicuous.
Absent:hairfolliclesinthecephalicregion.
14dpc(range13.5-15)
56-~60somitepairs
WitschiStage31(rat)
CarnegieStage20(atlas),21(atlas),22
(atlas),23(atlas),(human-stagetable)
Allscalebarsinmicrons.
Clickonanimageforalargerversion.
TheEdinburghMouseAtlas:
TheilerStage23-Toesseparate
PreviousStageStageIndexStageCriteriaAnatomyNextStage
Thetoesseparateandareclearlydivergent,not
lliclesare
presentinthecephalicregionbutnotatthe
nacoversmore
thanhalfoftheexternalauditorymeatusandthe
eyelidsarestillopen.
Absent:nailprimordia,fingers2-5parallel.
15dpc
>60somitepairs
WitschiStage32(rat)
Humanfoetalperiod.
Allscalebarsinmicrons.
Clickonanimageforalargerversion.
TheEdinburghMouseAtlas:
TheilerStage24-Repositionofumbilicalhernia
PreviousStageStageIndexStageCriteriaAnatomyNextStage
imordia
lidshavefused
inmostcasesbytheendofthestageandthe
pinnaalmostcompletelycoverstheexternal
ilicalherniais
disappearingandthereisacorresponding
increaseinthesizeoftheperitonealsac.
Absent:fingersandtoesjoinedtogether.
16dpc
>60Somitepairs
WitschiStage33(rat)
Allscalebarsinmicrons.
Clickonanimageforalargerversion.
TheEdinburghMouseAtlas:
TheilerStage25-Skinwrinkled
PreviousStageStageIndexStageCriteriaAnatomyNextStage
Theskinhasthickenedandformedwrinklesand
fingersandtoeshavebecomeparallelandthe
ids
rsarejustvisible.
Absent:earextendingoverauditorymeatus,
longwhiskers.
17dpc
WitschiStage34(rat)
Allscalebarsinmicrons.
Clickonanimageforalargerversion.
TheEdinburghMouseAtlas:
TheilerStage26-Longwhiskers
PreviousStageStageIndexStageCriteriaAnatomyNextStage
Thewhiskersvisibleatstage25aredefinitely
nais
largerandsuchthatvirtuallynoneofthelumenof
sarebarely
visiblethroughtheclosedeyelids
18dpc
Witschistage35(rat)
Allscalebarsinmicrons.
Clickonanimageforalargerversion.
TheEdinburghMouseAtlas:
TheilerStage27-Newbornmouse
PreviousStageStageIndexStageCriteriaAnatomyNextStage
Newborn
19-20dpc
Allscalebarsinmicrons.
Clickontheimageforalargerversion.
Mouseembryoscanbestagedaccordingtoavarietyofcriteria,themostgeneralofwhichare
thosedescribedbyTheilerin"
TheHouseMouse:AtlasofMouseDevelopment
"(Springer-Verlag,
NewYork,1989).Theiler'scriteriaaretoobroadtodistinguishmanyoftheimportantphasesof
earlydevelopmentandmustthereforebesupplementedbyothers,forexample,cellnumber,
somitenumberorthosecharcteristicsusedbyDownsandDavies(1993)Development,
118
,1255.
Wehavethereforecombinedthesedifferentcriteriainthetable
1
belowwhichdefinesanewset
ofstagesbasedonthenumberedTheilerseries,butwithintermediatedivisionsindicatedby
softhesamegestational
age
maydifferintheir
stage
of
thereforeincludedinthetableanindicationoftheexpectedrangeof
gestationalages(daysofgestation,dpc)overwhicheachdevelopmentalstagemaybefound.
Differentmousestrainsdevelopatdifferentratesand,insomecasesshowdifferencesinthe
ly,thestagesrecognisedbyDownsand
aintheremainderofthetablebelowrefer
toembryosofcrossesbetweenF1hybrid(C57BLXCBA)mice.
EachTheilerstageislinked(clickonthenumber)toitscorrespondingdiagram,withmoredetails
textorpictorialindextothediagramsisalso
provided.
TheilerSomite
dpc(range)
2
StageNo.
3
1
2
3
4
0-0.9
(0-2.5)
1
(1-2.5)
2
(1-3.5)
3
Cell
(C57BLxCBA)F1mice
4
number
1
2-4
4-16
16-40
One-cellegg
Dividingegg
Morula
Blastocyst,Innercellmassapparent
PO
mice
5
(2-4)
5
4
(3-5.5)
4.5
(4-5.5)
Blastocyst(zona-free)
Attachmentof
blastocyst
,primary
endodermcoversblastocoelicsurfaceof
innercellmass
Implantationandformationofegg
cylinderEctoplacentalconeappears,
enlargedepiblast,primaryendodermlines
muraltrophectoderm
Differentiationofeggcylinder.
acental
coneregioninvadedbymaternalblood,
Reichert'smembraneandproamniotic
cavityform
Pre-streak(PS),advancedendometrial
reaction,ectoplacentalconeinvadedby
PS
blood,extraembryonicectoderm,
embryonicaxisvisible,
Earlystreak(ES),gastrulationstarts,first
ES
evidenceofmesoderm
7
(6.5-7.75)
Midstreak(MS),amnioticfoldstartsto
MS
form
Latestreak,nobud(LSOB),exocoelom
Latestreak,earlybud(LSEB),allantoicbud
firstappears,node,amnionclosing
7.5
(7.25-8)
Neuralplate
(NP)
,head
developing,amnioncomplete
process
OB
LS
6
7
5
(4.5-6)
8
6
(5-6.5)
9a
6.5
(6.25-7.25)
9b
10a
10b
10c
11a
11b
11c
11d
8
(7.5-8.75)
Lateneuralplate(LNP),elongatedallantoic
EB/LB
bud
Earlyheadfold(EHF)
Lateheadfold(LHF),foregutinvagination
1-4somites,allantoisextends,1st
branchialarch,heartstartstoform,foregut
pocketvisible,preoticsulcus(at2-3somite
stage)
5-7somites,allantoiscontactschorionat
theendofTS12
Absent2ndarch,>7somites
Turningofthe
embryo
,1stbranchialarch
hasmaxillaryandmandibularcomponents,
EHF
LHF
12a1-4
12b
8.5
(8-9.25)
5-7
138-12
2ndarchpresent
Absent3rdbranchialarch
9
(8.5-9.75)
Formation&ore,
oticpitindentedbutnotclosed,3rd
branchialarchvisible
Absentforelimbbud
ore,forelimb
bud,forebrainvesiclesubdivides
Absenthindlimbbud,Rathke'spouch
Posteriorneuroporecloses,Formationof
hindlimb&tailbuds,lensplate,Rathke's
pouch;theindentednasalprocessesstart
toform
Absentthin&longtail
Deeplensindentation,n
tube,tailelongatesandthins,umbilical
herniastartstoform
Absentnasalpits
Closureoflensvesicle,nasalpits,cervical
somitesnolongervisible
Absentauditoryhillocks,anteriorfootplate
Lensvesiclecompletelyseparatedfrom
or,butno
posterior,ryhillocksfirst
visible
Absentretinalpigmentationandsignof
fingers
Earliestsignoffingers(splayed-out),
posteriorfootplateapparent,retina
pigmentationapparent,tongue
well-defined,brainvesiclesclear
Absent
5rowsofwhiskers,indented
anteriorfootplate
Anteriorfootplateindented,elbowand
wristidentifiable,5rowsofwhiskers,
umbilicalhernianowclearlyapparent
Absenthairfollicles,fingersseparate
distally
Fingersseparatedistally,onlyindentations
betweendigitsoftheposteriorfootplate,
longbonesoflimbspresent,hairfolliclesin
pectoral,pelvicandtrunkregions
1413-20
15
9.5
(9-10.25)
21-29
16
10
(9.5-10.75)
30-34
17
10.5
(10-11.25)
35-39
18
11
40-44
(10.5-11.25)
19
11.5
(11-12.25)
45-47
20
12
(11.5-13)
48-51
21
13
(12.5-14)
52-55
22
14
(13.5-15)
56-~60
Absentopeneyelids,hairfolliclesin
cephalicregion
Fingers&Toesseparate,hairfolliclesalso
incephalicregionbutnotatperipheryof
vibrissae,eyelidsopen
Absentnailprimordia,fingers2-5parallel
Repositionofumbilicalhernia,eyelids
closing,fingers2-5areparallel,nail
primordiavisibleontoes
Absentwrinkledskin,fingers&toesjoined
together
Skiniswrinkled,eyelidsare
closed,umbilicalherniaisgone
Absentearextendingoverauditory
meatus,longwhiskers
Longwhiskers
,eyesbarelyvisiblethrough
closedeyelids,earcoversauditorymeatus
NewbornMouse
Postnataldevelopment
2315
2416
2517
26
27
28
18
19
,J.B.L.,Kaufman,M.H.,Dubreuil,C.,Brune.R.M.,Burger,A.,Baldock,R.A.,Davidson,
D.R.(1998).Aninternet-accessibledatabaseofmousedevelopmentalanatomybasedon
asystematicnomenclature.
MechanismsofDevelopment
74,111-20.
stconception,withthemorningafterthevaginalplugisfoundbeingdesignated
0.5dpc(orE0.5).FordetaileddiscussionseeKaufman(1994).
TheAtlasofMouse
Development
(2ndprinting),:AcademicPress.
untistakenof
somitespartitioningintodermomyotomesandsclerotomes,noroftheirsubsequent
differentiation.
dfromTheiler(1989)[
TheHouseMouse:AtlasofEmbryonicDevelopment
.New
York:Springer-Verlag]andKaufman(1994);detailedstagingforTheilerstages9-12
[personalcommunication].
wnes,ies,T.(1993).Stagingofgastrulatingmouseembryosby
morphologicallandmarksinthedissectingmicroscope.
Development
,118,1255-1266.
Comments
Generalcommentontiming(dpc):
Injudgingthelowerandupperrangesofdpcequivalenttoa
particularTheilerstage,wehavegenerallyfollowedTheiler'sbookand,inmostcases,havegiven
awiderrangethanTheiler,givena
largerrangeatthemaximumthantheminimumbecause,ingeneral,embryosaremorelikelyto
beretardedbytheirenvironmentorgeneticconstitutionthanmadetoproceedmorequickly
cases,however,theresultingdpcrangeisanestimatethatis
consistentwiththeresultsofTheiler,butnotbasedonadditionalevidence.
Commentonsomitenumbers:
Therangeofsomitenumbersforeachstageisgivenonlyasa
eseenfromTheiler(1989)
4
thetrue
ore,forallstagesafterTS12,thesomitenumbershouldnotbe
takenasareliableglobalindicatoroftheoverallembryostage.
RichardBaldock,JonathanBard,DuncanDavidsonandKirstieLawson,7thMay1998
anBard
2024年9月25日发(作者：禚暮)
TheilerStage1-One-cellegg
Fertilizedone-cellstageegg(embryo),zona
pellucidapresent(showninred).
0-0.9dpc(range0-2.5)
Scalebarinmicrons
TheilerStage2-Dividingegg
Dividingeggstage,zonapellucidapresent(shown
inred).Firstcleavageoccursatabout24hours.
1dpc(range1-2.5)
2-4cells.
Scalebarinmicrons
TheilerStage3-Morula
Four-to16-cellstageembryosfromearlytofully
llucidapresent(shownin
red).Embryosintheoviducttowardsutero-tubal
junction.
2dpc(range1-3.5)
4-16cells.
Allscalebarsinmicrons.
TheilerStage4-Blastocyst(ICMapparent)
Embryoprogressesfrommorulatotheblastocyst
stillwithinthezonapellucida(showninred).Thereis
earlyevidenceoftheblastocoeliccavity.
3dpc(range2-4)
16-40compactedcells.
Allscalebarsinmicrons.
Intheblastocyststage(zona-intact)thereisa
distinctinnercellmassandanouterlayerof
ylocatedintheuterine
lumen.
TheilerStage5-Blastocyst(zona-free)
Blastocyst(zona-free),invariablylocatedwithin
theuterinelumen.
4dpc(range3-5.5)
Scalebarinmicrons
TheilerStage6-Attachmentofblastocyst
Blastocystsimplants,firstevidenceof
embryonicendodermcellscovering
theblastceolicsurfaceoftheinnercell
mass.
4.5dpc(range4-5.5)
WitschiStage8(rat)
CarnegieStage4(human)
Scalebar
TheilerStage7-ImplantationandformationofEgg
Cylinder
ncrease
inthenumberofinnercellmasscells
leadingtotheformationoftheepiblastwith
subsequentgrowthtoformtheegg
ximalorvisceralcells
(oppositesidefromthetrophoblasticcap)
yendoderm
linesthemuraltrophectoderm.
5dpc(range4.5-6)
WitschiStage10(rat)
CarnegieStage5(human)
Scale
TheilerStage8-Differentiationofeggcylinder
ernaltissueis
invadedbytrophoblast(primary)giantcellsand
theectoplacentalconeisinvadedbymaternal
entiationoftheeggcylinderinto
embryonicandextraembryonicregionsandthe
rt's
membrane,whichisnon-cellularandsecretedby
thedistalendodermfirstappears.
6dpc(range5-6.5)
WitschiStage10-11(rat)
CarnegieStage5(human)
Scalebarinmicrons
TheilerStage9-AdvancedEndometrialReaction
PS:Advancedegg-cylinderstagewiththefirst
sclear
morphologicaldistinctionbetweentheembryonic
oplacental
coneisfurtherinvadedbymaternalbloodandthe
originallumenoftheuterinecrypthas
disappeared.
ES:Lateinthisstagegastrulationbegins,
producingthefirstmesodermalcells.
6.5dpc(range6.25-7.25)
Downs&DaviesPS-ES:prestreaktoearly
streak
WitschiStage11(rat)
CarnegieStage6-7(human-stagetable)
Scalebarinmicrons.
TheilerStage10-Amnion
Gastrulationcontinuesthroughoutall
sub-divisionsofthisstageand:
MS:Tissueattheposteriorendoftheprimitive
streakbulgesintotheproamnioticcavityand
formstheposterioramnioticfold.
LSOB:Inthemesodermoftheposterioramniotic
foldsmallcavitiescoalescetoformasinglecavity,
theexocoelom.
LSEB:Theallantoicbudfirstappears,gastrulation
continuesandthenodebecomesvisible.
7dpc(range6.5-7.5)
Downs&DaviesMS-LSmidstreaktolate
streak
WitschiStage12(rat)
CarnegieStage8(human-stagetable)
Scalebarinmicrons.
TheilerStage11-NeuralPlate,PresomiteStage
NP:Theamnioticcavityissealedoffwithnow
threecavities-amniotic,exocoelomand
ralplateisdefined
themidline,sub-adjacenttotheneuralgroove,
thenotochodalplateisvisible.
LNP:Theallantoicbudelongates.
EHF:Therostraloftheneuralplatebeginsto
enlargetoformtheheadfolds.
LHF:Headfoldscontinuetoenlargeandthe
foregutpocketbeginstoform.
7.5dpc(range(7.25-8)
Downs&DaviesOB-EB/LB-EHF-LHF:-noAll.
arlyheadfoldtolatehead
fold
WitschiStage12-13(rat)
CarnegieStage9(human-stagetable)
Scalebarinmicrons.
TheilerStage12-Firstsomites
Unturnedembryowithfirstappearence
ofsomitepairs.
1-4somites:Theallantoisextends
furtherintotheexocoelomandthe
maxiliarycomponentsofthe1st
preoticsulcusisvisibleinthe2-3
diogenicplate
beginstoformandtheforegutpocketis
clearlyvisible.
5-7:Theheadfoldsareparticularly
prominentandneuralclosureoccursin
theregionofthe4thand5thsomites,
extendinginbothdirectionsfromthis
icplacodesarefirstevident
andbecomeindentedtoformtheoptic
rtrudimentdevelops
antoiscontactsthe
chorionattheendofthisstage.
Absent:The2ndbranchialarchand>7
somites.
8dpc(range7.5-8.75)
1-7somitepairs
WitschiStage14-15(rat)
CarnegieStage9(human-stagetable)
Allscalebarsinmicrons
Clickonanimageforalargerversion
TheilerStage13-Turningoftheembryo
Thisisashortperiodwithturninginitiatedin
embryoswith6-8pairsofsomitesandusually
completedinembryoswith14-16pairsof
stbranchialarchhas
maxillaryandmandibularcomponentsbut
themaxillaryprocessisnotvisibleuntillater
(TS16).Asecondbranchialarchisnow
sevidenceofregionalisation
oftheheartandtheneuraltubeisclosed
fromapointoppositetheoutflowtracttothe
proximalpartofthetail.
Absent:3rdbranchialarch.
8.5dpc(range8-9.25)
8-12somitepairs
WitschiStage15(rat)
CarnegieStage10(human-stagetable)
Allscalebarsinmicrons.
Clickonanimageforalargerversion.
TheilerStage14-Formationandclosureofanterior
neuropore
Therostralextremityoftheneuraltubeclosesin
embryoswithusuallyabout15-18somitepairs
cpitbecomes
progressivelymoreindentedbutnotclosed,the
mandibularprocessofthe1stbranchialarchis
3rdbranchialarchbecomes
easingly
prominentridgeonthelateralbodywall,
approximatelyatthelevelofthe8th-12thsomite,
indicatesthesiteofthefutureforelimbbud.
Absent:forelimbbud.
9dpc(range8.5-9.75)
13-20somitepairs
WitschiStage16(rat)
CarnegieStage11(human-stagetable)
Allscalebarsinmicrons.
Clickonanimageforalargerversion.
TheilerStage15-Formationofposteriorneuropore;
forelimbbud
Theposteriorneuroporeformandthe
condensationoftheforelimbbudbecomes
apparentnearthe8th-12thsomitepairs.
Adistinctcondensationofthehindlimb
budappearsjustattheendofthestage.
Theforebrainvesiclesubdividesinto
telencephalicanddiencephalicvesicles.
Absent:hindlimbbud,Rathke'spouch.
9.5dpc(range9-10.25)
21-29somitepairs
WitschiStage17-19(rat)
CarnegieStage12(human-stagetable)
Allscale
bars
inmicrons.
Clickonanimageforalargerversion
TheilerStage16-Closureofposteriorneuropore;hind
limbbudandtailbud
Thehindlimbbudbecomesvisibleat
tailbudappearsasashortstumpand
the3rdand4thbranchialarchesare
'spouchand
endofthisstagetheposterior
neuroporebeginstoclose.
Absent:thinandlongtail.
10dpc(range9.5-10.75)
30-34somitepairs
WitschiStage20-21(rat)
CarnegieStage13(atlas),14(atlas),
15(atlas)(human-stagetable)
Allscale
bars
inmicrons.
Clickonanimageforalargerversion.
TheilerStage17-Deeplensindentation
Themostobviousdistinguishing
featuresarethedeepeningofthelens
pit,withanarrowingofit'souter
pore-likeopening,andthefirst
appearenceofthephysiological
1stbranchial
archisconspicuouslydividedintoit
maxillaryandmandibular
sadvanced
developmentofthebraintubeandthe
tailelongatesandthins.
Absent:nasalpits.
10.5dpc(range10-11.25)
35-39somitepairs
WitschiStage24-25(rat)
CarnegieStage13(atlas),14(atlas),
15(atlas)(human-stagetable)
Allscalebarsinmicrons.
Clickonanimageforalargerversion.
TheilerStage18-Closureoflensvesicle
Theprimaryexternallyrecognisablefeatureis
somitesinthecervicalregionarenolonger
visibleandtherapidgrowthofthebrainis
alpitsstarttoform.
Absent:auditoryhillocks,anteriorfootplate.
11dpc(range10.5-11.25)
40-44somitepairs
WitschiStage25-26(rat)
CarnegieStage13(atlas),14(atlas),15
(atlas)(human-stagetable)
Allscalebarsinmicrons.
Clickonanimageforalargerversion
TheilerStage19-Lensvesiclecompletelyseparated
fromsurface
Thelensvesiclebecomescompletelyclosedand
ipheral
forelimbsareseentobedividedintotworegions,
theproximalpartconsistingofthefuture
limb-girdleandarmandthemoreperipheralpart
whichformsacircularorpaddle-shaped
handplate(anteriorfootplate).Themedialand
lateralmarginsoftheoticpitarecomingtogether
reducingtheentrancetoanarrowslitandthe
auditoryhillocksbecomevisible.
Absent:retinalpigmentation,signsoffingers.
11.5dpc(range11-12.25)
45-47somitepairs
WitschiStage26-27(rat)
CarnegieStage16(atlas),(human-stagetable)
Allscalebarsinmicrons.
Clickonanimageforalargerversion.
TheilerStage20-Earliestsignsof
fingers
PreviousStageStageIndexStageCriteriaAnatomyNextStage
Thehandplate(anteriorfootplate)isnolonger
circularbutdevelopsangleswhichcorrespond
teriorfootplateis
alsodistinguishablefromthelowerpartofthe
ssibletoseethepigmentationofthe
pigmentedlayeroftheretinathroughthe
gueandbrain
vesiclesareclearlyvisible.
Absent:5rowsofwhiskers,indentedhandplate.
12dpc(range11.5-13)
48-51somitepairs
WitschiStage28(rat)
CarnegieStage17(atlas),(human-stage
table)
Allscalebarsinmicrons.
Clickonanimageforalargerversion
TheEdinburghMouseAtlas:
TheilerStage21-Anteriorfootplateindented
PreviousStageStageIndexStageCriteriaAnatomyNextStage
Thedistalbordersoftheanteriorandposterior
footplatesarenowindentedandthedigitwidths
owand
narapidly
developsandformsacrestatrightanglestothe
wsofvibrissaearevisibleaswellas
aprominanthairfollicleovertheeyeandanother
svesiclehaslostit'slumen.
Thephysiologicalumbilicalherniaisprominent.
Absent:hairfollicles,distallyseparatefingers.
13dpc(range12.5-14)
52-55somitepairs
WitschiStage29-30(rat)
CarnegieStage18(atlas),19(atlas),(human-
stagetable)
Allscalebarsinmicrons.
Clickonanimageforalargerversion.
TheEdinburghMouseAtlas:
TheilerStage22-Fingersseparate
distally
PreviousStageStageIndexStageCriteriaAnatomyNextStage
Individualfingersarevisibleintheanterior
footplateandtherearedeepindentations
betweenthetoeswhicharenotyetseparated.
Thelongbonesofthelimbsarepresentand
therearehairfolliclesinthepectoral,pelvicand
naisturnedforwardsand
theumbilicalherniaisconspicuous.
Absent:hairfolliclesinthecephalicregion.
14dpc(range13.5-15)
56-~60somitepairs
WitschiStage31(rat)
CarnegieStage20(atlas),21(atlas),22
(atlas),23(atlas),(human-stagetable)
Allscalebarsinmicrons.
Clickonanimageforalargerversion.
TheEdinburghMouseAtlas:
TheilerStage23-Toesseparate
PreviousStageStageIndexStageCriteriaAnatomyNextStage
Thetoesseparateandareclearlydivergent,not
lliclesare
presentinthecephalicregionbutnotatthe
nacoversmore
thanhalfoftheexternalauditorymeatusandthe
eyelidsarestillopen.
Absent:nailprimordia,fingers2-5parallel.
15dpc
>60somitepairs
WitschiStage32(rat)
Humanfoetalperiod.
Allscalebarsinmicrons.
Clickonanimageforalargerversion.
TheEdinburghMouseAtlas:
TheilerStage24-Repositionofumbilicalhernia
PreviousStageStageIndexStageCriteriaAnatomyNextStage
imordia
lidshavefused
inmostcasesbytheendofthestageandthe
pinnaalmostcompletelycoverstheexternal
ilicalherniais
disappearingandthereisacorresponding
increaseinthesizeoftheperitonealsac.
Absent:fingersandtoesjoinedtogether.
16dpc
>60Somitepairs
WitschiStage33(rat)
Allscalebarsinmicrons.
Clickonanimageforalargerversion.
TheEdinburghMouseAtlas:
TheilerStage25-Skinwrinkled
PreviousStageStageIndexStageCriteriaAnatomyNextStage
Theskinhasthickenedandformedwrinklesand
fingersandtoeshavebecomeparallelandthe
ids
rsarejustvisible.
Absent:earextendingoverauditorymeatus,
longwhiskers.
17dpc
WitschiStage34(rat)
Allscalebarsinmicrons.
Clickonanimageforalargerversion.
TheEdinburghMouseAtlas:
TheilerStage26-Longwhiskers
PreviousStageStageIndexStageCriteriaAnatomyNextStage
Thewhiskersvisibleatstage25aredefinitely
nais
largerandsuchthatvirtuallynoneofthelumenof
sarebarely
visiblethroughtheclosedeyelids
18dpc
Witschistage35(rat)
Allscalebarsinmicrons.
Clickonanimageforalargerversion.
TheEdinburghMouseAtlas:
TheilerStage27-Newbornmouse
PreviousStageStageIndexStageCriteriaAnatomyNextStage
Newborn
19-20dpc
Allscalebarsinmicrons.
Clickontheimageforalargerversion.
Mouseembryoscanbestagedaccordingtoavarietyofcriteria,themostgeneralofwhichare
thosedescribedbyTheilerin"
TheHouseMouse:AtlasofMouseDevelopment
"(Springer-Verlag,
NewYork,1989).Theiler'scriteriaaretoobroadtodistinguishmanyoftheimportantphasesof
earlydevelopmentandmustthereforebesupplementedbyothers,forexample,cellnumber,
somitenumberorthosecharcteristicsusedbyDownsandDavies(1993)Development,
118
,1255.
Wehavethereforecombinedthesedifferentcriteriainthetable
1
belowwhichdefinesanewset
ofstagesbasedonthenumberedTheilerseries,butwithintermediatedivisionsindicatedby
softhesamegestational
age
maydifferintheir
stage
of
thereforeincludedinthetableanindicationoftheexpectedrangeof
gestationalages(daysofgestation,dpc)overwhicheachdevelopmentalstagemaybefound.
Differentmousestrainsdevelopatdifferentratesand,insomecasesshowdifferencesinthe
ly,thestagesrecognisedbyDownsand
aintheremainderofthetablebelowrefer
toembryosofcrossesbetweenF1hybrid(C57BLXCBA)mice.
EachTheilerstageislinked(clickonthenumber)toitscorrespondingdiagram,withmoredetails
textorpictorialindextothediagramsisalso
provided.
TheilerSomite
dpc(range)
2
StageNo.
3
1
2
3
4
0-0.9
(0-2.5)
1
(1-2.5)
2
(1-3.5)
3
Cell
(C57BLxCBA)F1mice
4
number
1
2-4
4-16
16-40
One-cellegg
Dividingegg
Morula
Blastocyst,Innercellmassapparent
PO
mice
5
(2-4)
5
4
(3-5.5)
4.5
(4-5.5)
Blastocyst(zona-free)
Attachmentof
blastocyst
,primary
endodermcoversblastocoelicsurfaceof
innercellmass
Implantationandformationofegg
cylinderEctoplacentalconeappears,
enlargedepiblast,primaryendodermlines
muraltrophectoderm
Differentiationofeggcylinder.
acental
coneregioninvadedbymaternalblood,
Reichert'smembraneandproamniotic
cavityform
Pre-streak(PS),advancedendometrial
reaction,ectoplacentalconeinvadedby
PS
blood,extraembryonicectoderm,
embryonicaxisvisible,
Earlystreak(ES),gastrulationstarts,first
ES
evidenceofmesoderm
7
(6.5-7.75)
Midstreak(MS),amnioticfoldstartsto
MS
form
Latestreak,nobud(LSOB),exocoelom
Latestreak,earlybud(LSEB),allantoicbud
firstappears,node,amnionclosing
7.5
(7.25-8)
Neuralplate
(NP)
,head
developing,amnioncomplete
process
OB
LS
6
7
5
(4.5-6)
8
6
(5-6.5)
9a
6.5
(6.25-7.25)
9b
10a
10b
10c
11a
11b
11c
11d
8
(7.5-8.75)
Lateneuralplate(LNP),elongatedallantoic
EB/LB
bud
Earlyheadfold(EHF)
Lateheadfold(LHF),foregutinvagination
1-4somites,allantoisextends,1st
branchialarch,heartstartstoform,foregut
pocketvisible,preoticsulcus(at2-3somite
stage)
5-7somites,allantoiscontactschorionat
theendofTS12
Absent2ndarch,>7somites
Turningofthe
embryo
,1stbranchialarch
hasmaxillaryandmandibularcomponents,
EHF
LHF
12a1-4
12b
8.5
(8-9.25)
5-7
138-12
2ndarchpresent
Absent3rdbranchialarch
9
(8.5-9.75)
Formation&ore,
oticpitindentedbutnotclosed,3rd
branchialarchvisible
Absentforelimbbud
ore,forelimb
bud,forebrainvesiclesubdivides
Absenthindlimbbud,Rathke'spouch
Posteriorneuroporecloses,Formationof
hindlimb&tailbuds,lensplate,Rathke's
pouch;theindentednasalprocessesstart
toform
Absentthin&longtail
Deeplensindentation,n
tube,tailelongatesandthins,umbilical
herniastartstoform
Absentnasalpits
Closureoflensvesicle,nasalpits,cervical
somitesnolongervisible
Absentauditoryhillocks,anteriorfootplate
Lensvesiclecompletelyseparatedfrom
or,butno
posterior,ryhillocksfirst
visible
Absentretinalpigmentationandsignof
fingers
Earliestsignoffingers(splayed-out),
posteriorfootplateapparent,retina
pigmentationapparent,tongue
well-defined,brainvesiclesclear
Absent
5rowsofwhiskers,indented
anteriorfootplate
Anteriorfootplateindented,elbowand
wristidentifiable,5rowsofwhiskers,
umbilicalhernianowclearlyapparent
Absenthairfollicles,fingersseparate
distally
Fingersseparatedistally,onlyindentations
betweendigitsoftheposteriorfootplate,
longbonesoflimbspresent,hairfolliclesin
pectoral,pelvicandtrunkregions
1413-20
15
9.5
(9-10.25)
21-29
16
10
(9.5-10.75)
30-34
17
10.5
(10-11.25)
35-39
18
11
40-44
(10.5-11.25)
19
11.5
(11-12.25)
45-47
20
12
(11.5-13)
48-51
21
13
(12.5-14)
52-55
22
14
(13.5-15)
56-~60
Absentopeneyelids,hairfolliclesin
cephalicregion
Fingers&Toesseparate,hairfolliclesalso
incephalicregionbutnotatperipheryof
vibrissae,eyelidsopen
Absentnailprimordia,fingers2-5parallel
Repositionofumbilicalhernia,eyelids
closing,fingers2-5areparallel,nail
primordiavisibleontoes
Absentwrinkledskin,fingers&toesjoined
together
Skiniswrinkled,eyelidsare
closed,umbilicalherniaisgone
Absentearextendingoverauditory
meatus,longwhiskers
Longwhiskers
,eyesbarelyvisiblethrough
closedeyelids,earcoversauditorymeatus
NewbornMouse
Postnataldevelopment
2315
2416
2517
26
27
28
18
19
,J.B.L.,Kaufman,M.H.,Dubreuil,C.,Brune.R.M.,Burger,A.,Baldock,R.A.,Davidson,
D.R.(1998).Aninternet-accessibledatabaseofmousedevelopmentalanatomybasedon
asystematicnomenclature.
MechanismsofDevelopment
74,111-20.
stconception,withthemorningafterthevaginalplugisfoundbeingdesignated
0.5dpc(orE0.5).FordetaileddiscussionseeKaufman(1994).
TheAtlasofMouse
Development
(2ndprinting),:AcademicPress.
untistakenof
somitespartitioningintodermomyotomesandsclerotomes,noroftheirsubsequent
differentiation.
dfromTheiler(1989)[
TheHouseMouse:AtlasofEmbryonicDevelopment
.New
York:Springer-Verlag]andKaufman(1994);detailedstagingforTheilerstages9-12
[personalcommunication].
wnes,ies,T.(1993).Stagingofgastrulatingmouseembryosby
morphologicallandmarksinthedissectingmicroscope.
Development
,118,1255-1266.
Comments
Generalcommentontiming(dpc):
Injudgingthelowerandupperrangesofdpcequivalenttoa
particularTheilerstage,wehavegenerallyfollowedTheiler'sbookand,inmostcases,havegiven
awiderrangethanTheiler,givena
largerrangeatthemaximumthantheminimumbecause,ingeneral,embryosaremorelikelyto
beretardedbytheirenvironmentorgeneticconstitutionthanmadetoproceedmorequickly
cases,however,theresultingdpcrangeisanestimatethatis
consistentwiththeresultsofTheiler,butnotbasedonadditionalevidence.
Commentonsomitenumbers:
Therangeofsomitenumbersforeachstageisgivenonlyasa
eseenfromTheiler(1989)
4
thetrue
ore,forallstagesafterTS12,thesomitenumbershouldnotbe
takenasareliableglobalindicatoroftheoverallembryostage.
RichardBaldock,JonathanBard,DuncanDavidsonandKirstieLawson,7thMay1998
anBard