Theiler Staging Criteria for Mouse Embryo Development For full descriptions of Theiler staging and mouse anatomy visit http://genex.hgu.mrc.ac.uk/Atlas/intro.html TS 1 TS 2 TS 3 TS.
Download ReportTranscript Theiler Staging Criteria for Mouse Embryo Development For full descriptions of Theiler staging and mouse anatomy visit http://genex.hgu.mrc.ac.uk/Atlas/intro.html TS 1 TS 2 TS 3 TS.
Theiler Staging Criteria for Mouse Embryo Development
For full descriptions of Theiler staging and mouse anatomy visit http://genex.hgu.mrc.ac.uk/Atlas/intro.html
TS 1
(0-2.5)
TS 2
(1-2.5)
TS 3
(1-3.5)
TS 4
(2-4)
TS 5
(3-5.5)
TS 6
(4-5.5)
TS 7
(4.5-6)
TS 8
(5-6.5)
TS 9
a
(6.25-7.25)
b
One-cell egg Dividing egg 2-4 cells Morula 4-16 cells
Blastocyst, inner cell mass apparent
16-40 cells
Figures represent development of F1 hybrid (C57BL X CBA) mice. Descriptions of embryos at TS9 – 11 based on Downs & Davies, 1993, and apply to outbred mice of the PO strain. Numbers in parentheses under Theiler stages represent approximate dpc range. Relative sizes of illustrations not to scale. The cartoons are intended as a illustrative guide only.
Blastocyst
(zona-free)
Attachment of
blastocyst, primary endoderm covers blastocoelic surface of inner cell mass
Implantation and formation
of egg cylinder. Ectoplacental cone appears, enlarged epiblast, primary endoderm lines mural trophectoderm
Differentiation
of egg cylinder. Implantation sites 2x3mm.
Ectoplacental cone region invaded by maternal blood, Reichertís membrane and proamniotic cavity form
First sign of radial asymmetry. a Pre-streak
(PS), advanced endometrial reaction, ectoplacental cone invaded by blood, extraembryonic ectoderm, embryonic axis visible.
b Early streak
(ES), gastrulation starts, first evidence of mesoderm.
Theiler Stage
dpc
1 1 2 1 3 2 4 3 5 4 6 4.5
7 5 8 6 9 6.5
10 7 11 7.5
12 8 13 8.5
14 9 15 9.5
16 10 17 10.5
18 11 19 11.5
20 12 21 13 22 14 23 15 24 16 25 17 26 18 27 19
Theiler Staging Criteria for Mouse Embryo Development
For full descriptions of Theiler staging and mouse anatomy visit http://genex.hgu.mrc.ac.uk/Atlas/intro.html
a
TS 10
(6.5-7.75)
a
TS 11
(7.25-8)
TS 12
(7.5-8.75)
TS 13
(8-9.25)
TS 14
(8.5-9.75)
TS 15
(9-10.25)
TS 16
(9.5-10.75)
TS 17
(10-11.25)
TS 18
(10.5-11.25)
b b c c
Turning of the
embryo, 1st branchial arch has maxillary and mandibular components, 2nd arch present
8-12 somites.
Absent 3rd branchial arch
Formation & closure of ant.
neuropore, otic pit indented but not closed, 3rd branchial arch visible
13-20 somites.
Absent forelimb bud a Neural plate (NP), head process developing, amnion complete
b Late neural plate
(LNP), elongated allantoic bud
c Early head fold (EHF)
d Late head fold (LHF), foregut invagination
First appearance of somites.
1-4 somites, allantois extends, 1st branchial arch, heart starts to form, foregut pocket visible, preotic sulcus (at 2-3 somite stage).
5-7 somites, allantois contacts chorion at the end of TS12 Absent 2nd arch, >7 somites
Formation of post.
neuropore, forelimb bud, forebrain vesicle subdivides
21-29 somites.
Absent hindlimb bud, Rathke's pouch
Posterior neuropore
closes, Formation of hindlimb & tail buds, lens plate, Rathke's pouch; the indented nasal processes start to form
30-34 somites.
Absent thin & long tail
Deep lens
indentation, adv. devel. of brain tube, tail elongates and thins, umbilical hernia starts to form
35-39 somites.
Absent nasal pits a Mid streak (MS), amniotic fold starts to form.
b Late streak, no
bud (LSOB), exocoelom.
c Late streak, early
bud (LSEB), allantoic bud first appears, node, amnion closing
d
Theiler Stage
dpc
1 1 2 1 3 2 4 3 5 4 6 4.5
7 5 8 6 9 6.5
10 7 11 7.5
12 8 13 8.5
14 9 15 9.5
16 10 17 10.5
18 11 19 11.5
20 12 21 13 22 14 23 15 24 16 25 17 26 18 27 19
Closure of lens
vesicle, nasal pits, cervical somites no longer visible
40-44 somites.
Absent auditory hillocks, anterior footplate
Theiler Staging Criteria for Mouse Embryo Development
For full descriptions of Theiler staging and mouse anatomy visit http://genex.hgu.mrc.ac.uk/Atlas/intro.html
TS 19
(11-12.25)
TS 20
(11.5-13)
TS 21
(12.5-14)
TS 22
(13.5-15)
TS 23 TS 24 TS 25 TS 26 TS 27
Lens vesicle completely separated from the surface
epithelium. Anterior, but no posterior, footplate. Auditory hillocks first visible
45-47 somites.
Absent retinal pigmentation and sign of fingers
Earliest sign of fingers (splayed-
out), posterior footplate apparent, retina pigmentation apparent, tongue well defined, brain vesicles clear
48-51 somites.
Absent 5 rows of whiskers, indented anterior footplate
Anterior footplate
indented, elbow and wrist identifiable, 5 rows of whiskers, umbilical hernia now clearly apparent
52-55 somites.
Absent hair follicles, fingers separate distally
Fingers separate
distally, only indentations between digits of the posterior footplate, long bones of limbs present, hair follicles in pectoral, pelvic and trunk region
56-~60 somites.
Absent open eyelids, hair follicles in cephalic region
Fingers & toes
separate, hair follicles also in cephalic region but not at periphery of vibrissae, eyelids open. Absent nail primordia, fingers 2 5 parallel
Repositioning of
umbilical hernia, eyelids closing, fingers 2-5 are parallel, nail primordia visible on toes.
Absent wrinkled skin, fingers & toes joined together Skin is wrinkled, eyelids are closed,umbilical hernia is gone. Absent ear extending over auditory meatus, long whiskers Long whiskers, eyes barely visible through closed eyelids, ear covers auditory meatus
Newborn mouse Theiler Stage
dpc
1 1 2 1 3 2 4 3 5 4 6 4.5
7 5 8 6 9 6.5
10 7 11 7.5
12 8 13 8.5
14 9 15 9.5
16 10 17 10.5
18 11 19 11.5
20 12 21 13 22 14 23 15 24 16 25 17 26 18 27 19