Rat Development

From Embryology
Embryology - 23 May 2019    Facebook link Pinterest link Twitter link  Expand to Translate  
Google Translate - select your language from the list shown below (this will open a new external page)

العربية | català | 中文 | 中國傳統的 | français | Deutsche | עִברִית | हिंदी | bahasa Indonesia | italiano | 日本語 | 한국어 | မြန်မာ | Pilipino | Polskie | português | ਪੰਜਾਬੀ ਦੇ | Română | русский | Español | Swahili | Svensk | ไทย | Türkçe | اردو | ייִדיש | Tiếng Việt    These external translations are automated and may not be accurate. (More? About Translations)

Introduction

Rat.jpg

The rat (taxon - rattus) is readily available as inbred, outbred and mutant strains. They have been generally beaten as a model by their rodent mice brethren, as the molecular tools that became available (stem cells, knockout genes, etc).


Rat embryos do have the advantage of being much larger than mouse embryos and easy to breed. Another advantage of rats is in vision development studies, as that retinal development continues postnatally (most vertebrate neurological systems are difficult to access during periods of development). Rat development is also generally 1 day behind that of mouse. (The table below gives details relating to the staging of rat development).

Huber in 1915 first described the early development of the albino rat (Mus Norvegicus Albinus) within the uterus from pronuclear stage to day 9.[1]

Rat Links: rat | Rat Stages | Rat Timeline | Category:Rat
Historic Embryology - Rat 
1951 Albino Rat Development | 1921 Somitogenesis | 1925 Neural Folds and Cranial Ganglia | 1933 Vaginal smear | 1938 Heart

Some Recent Findings

  • Ultrasonographic evaluation of fetal development in the rat[2] "The study objectives were to measure gestational sac (GS) diameter and crown-to-rump (CR) length in conscious pregnant rats and to determine the chronological ultrasonographic appearance of heart beat and fetal organogenesis. The study formed part of a unilateral surgical salpingectomy trial with 16 female Sprague-Dawley rats (Rattus norvegicus). Ten rats were operated on while the other six served as controls. After surgery all were mated at 8-10 weeks of age. Gestational length was taken as 22 days. Rats were manually restrained for abdominal ultrasonography and were scanned daily from day 7 until day 19 or 20 post-mating followed by immediate euthanasia. Mean GS diameters ranged from 2.9  mm (day 7) to 18 1 mm (day 20). A string of pearls was seen on days 8-11. The CR length ranged from 1.6  mm (day 11) to 26. 4 mm (day 20). A heart beat was first seen on day 11 and the echogenic vertebral column at day 14-15. From day 16, ribs, feet and the isoechoic lungs and liver were seen. The lungs became hyperechoic to the liver from day 18-19. The tail and mandible were visible on day 18 and the aorta and caudal vena cava were seen on day 19, as well as an occasional bladder." ultrasound
  • Cross-Species Genome Wide Expression Analysis during Pluripotent Cell Determination in Mouse and Rat Preimplantation Embryos[3] "The transition between morula and blastocyst stage during preimplantation development represents the first differentiation event of embryogenesis. Morula cells undergo the first cellular specialization and produce two well-defined populations of cells, the trophoblast and the inner cell mass (ICM). ... This is the first study investigating the gene expression changes during the transition from morula to blastocyst in the rat preimplantation development. Our data show that in the pluripotent pool of cells of the rat and mouse preimplantation embryo substantial differential regulation of genes is present, which might explain the difficulties observed for the derivation and culture of rat ESCs using mouse conditions."
More recent papers  
Mark Hill.jpg
PubMed logo.gif

This table allows an automated computer search of the external PubMed database using the listed "Search term" text link.

  • This search now requires a manual link as the original PubMed extension has been disabled.
  • The displayed list of references do not reflect any editorial selection of material based on content or relevance.
  • References also appear on this list based upon the date of the actual page viewing.


References listed on the rest of the content page and the associated discussion page (listed under the publication year sub-headings) do include some editorial selection based upon both relevance and availability. {More? References | Discussion Page | Journal Searches)


Search term: Rat Embryology | Rat Development

Older papers  
These papers originally appeared in the Some Recent Findings table, but as that list grew in length have now been shuffled down to this collapsible table.

See also the Discussion Page for other references listed by year and References on this current page.

  • Generation of germline-competent rat induced pluripotent stem cells[4] "Our data clearly demonstrate that using only three reprogramming factors (Oct3/4, Klf4, and Sox2) rat somatic cells can be reprogrammed into a ground state. Our generated riPSCs exhibited germline transmission in either rat-rat intraspecific or mouse-rat interspecific chimeras."
  • Comparison of staging systems for the gastrulation and early neurulation period in rodents[5]"Because there is no standard developmental staging system for the early postimplantation period of rodent embryos, investigators must now choose between a variety of systems that differ significantly. We have reviewed many of these staging systems and have summarized the ambiguities within them and the inconsistencies among them. In order to compare systems, we first obtained a consensus of the order of developmental events from the literature, and then attempted to fit existing systems into this order taking into account inconsistencies in terminology and blurred borderlines between stages."

Rat Estrous Cycle

Left oviduct of rat
Left oviduct of rat

See the review of the rat estrous cycle.[6] One of the best characterised polyestrous reproductive cycles, though different species of rats may differ in reproduction. In general, puberty occurs at 6-8 weeks when the estrous cycle commences each cycle is 4-5 days. The estrous cycle is polyestrous, more than one estrous cycle during a specific yearly time, with an estrous period of approximately 12 hours.


Links: estrous cycle | PubMed Search - rat estrous cycle

Species Stages Comparison

The table below gives an approximate comparison of human, mouse and rat embryos based upon Carnegie staging.

Species Embryonic Comparison Timeline
Carnegie Stage
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
Human Days 1 2-3 4-5 5-6 7-12 13-15 15-17 17-19 20 22 24 28 30 33 36 40 42 44 48 52 54 55 58
Mouse Days 1 2 3 E4.5 E5.0 E6.0 E7.0 E8.0 E9.0 E9.5 E10 E10.5 E11 E11.5 E12 E12.5 E13 E13.5 E14 E14.5 E15 E15.5 E16
Rat Days 1 3.5 4-5 5 6 7.5 8.5 9 10.5 11 11.5 12 12.5 13 13.5 14 14.5 15 15.5 16 16.5 17 17.5
Note these Carnegie stages are only approximate day timings for average of embryos. Links: Carnegie Stage Comparison
Table References  
Human

O'Rahilly R. (1979). Early human development and the chief sources of information on staged human embryos. Eur. J. Obstet. Gynecol. Reprod. Biol. , 9, 273-80. PMID: 400868
Otis EM and Brent R. Equivalent ages in mouse and human embryos. (1954) Anat Rec. 120(1):33-63. PMID 13207763

Mouse
Theiler K. The House Mouse: Atlas of Mouse Development (1972, 1989) Springer-Verlag, NY. Online
OTIS EM & BRENT R. (1954). Equivalent ages in mouse and human embryos. Anat. Rec. , 120, 33-63. PMID: 13207763

Rat
Witschi E. Rat Development. In: Growth Including Reproduction and Morphological Development. (1962) Altman PL. and Dittmer DS. ed. Fed. Am. Soc. Exp. Biol., Washington DC, pp. 304-314.
Pérez-Cano FJ, Franch À, Castellote C & Castell M. (2012). The suckling rat as a model for immunonutrition studies in early life. Clin. Dev. Immunol. , 2012, 537310. PMID: 22899949 DOI.


Animal Model Comparison
Postnatal Animal Models mouse rat pig
Pregnancy period (days) 18 – 21 21 – 23 110 – 118
Placenta type Discoidal, decidual
hemoendothelial choroidea
Discoidal, decidual
hemoendothelial choroidea
Epitheliochorial
Litter size 6 – 12 6 – 15 11 – 16
Birth weight (g) 0.5 – 1.5 3 – 5 900 – 1600
Weaning weight male/female (g) 18 – 25/16 – 25 55 – 90/45 – 80 6000 – 8000
Suckling period (days) 21–28 21 28–49
Solid diet beginning (days) 10 12 12 – 15
Puberty male/female (week) 4 – 6/5 6/6 – 8 20 – 28
Life expectancy (years) 1 - 2 2 - 3 14 – 18
Table data - Otis and Brent (1954)[7]   Links: timeline

Rat oocyte 01.jpg

Rat oocytes showing metaphase plate[8]


Links: Rat Timeline

Somite Development

Table III - Showing Means and Variation for Each Rat Age
Maximum Variation
Age
Days-Hrs.
Number of
Litters
Number of
Embryos
Counted
Means All Embryos One Litter Standard
Deviation
Coefficient of
Variation %
10-12 1 4 8.7 6-11 6-11 2.8 32
10-13 1 6 1 0. 2 8-13 8-13 1.9 19
10-16 2 12 12.4 6-26 6-26 5.8 47
10-17 6 48 12.9 4-26 7-26 3 .3 26
10-18 4 23 14.1 6-18 9-18 3.1 22
10-19 1 6 14 .3 12-17 12-17 1.2 8
10-22 3 16 13.1 6-19 6-14 3.9 30
10-23 3 17 15.2 8-18 8-18 2.4 16
11-00 2 0 14.6 10-17 10-17 1.9 13
11-02 2 15 20 . 9 17-22 17-22 1. 3 6
11-04 1 10 25. 3 23-26 23-26 1.2 5
11-06 1 2 18.0 18-18 18-18 .0 0
11-08 1 8 25 0 23-28 23-28 1.9 8
11-09 1 3 22 .0 20-25 20-25 2 . 2 10
11-10 2 18 26.2 21-31 21-31 2.9 11
11-11 3 26 25.6 14-29 14-27 3.2 12
11-12 1 3 26. 7 25-28 25-28 1.2 4
11-14 1 3 21.3 21-22 21-22 .6 2
11-15 1 8 23.1 17-28 17-28 4 . 0 17
11-16 1 7 26.7 24-28 24-28 1.3 5
11-17 1 7 26.1 25-28 25-28 1.1 4
11-18 3 25 25 .4 19-28 19-28 1.9 7
11-20 2 16 27.2 25-29 25-29 1.2 4
23 Ages 44 292 Av 2.2 Av 13%
Data Reference[9]   Links: rat | somitogenesis

Placenta Development

For review of the rat placenta.[10]

Adrenal and Gonad Development

Adrenal and gonad steroidogenic factor 1 expression.jpg

Adrenal and gonad steroidogenic factor 1 expression[11]

Animal Model Differences

The rat is a common model of human development with some developmental and anatomical differences.

  • liver lobation with obvious connective tissue septa, less connective tissue in human liver.[12]
  • gallbladder absent in rats.[12]
  • increased role of hepatic artery in lobular perfusion in humans.[12]


References

  1. Huber GC. The Development of the Albino Rat (Mus norvegicus albinus). (1915) J. Morphology 26(2).
  2. Kirberger RM, Bester EG, Schulman ML, Janse van Rensburg I & Hartman MJ. (2019). Ultrasonographic evaluation of fetal development in the rat. Theriogenology , 125, 24-29. PMID: 30388467 DOI.
  3. Casanova EA, Okoniewski MJ & Cinelli P. (2012). Cross-species genome wide expression analysis during pluripotent cell determination in mouse and rat preimplantation embryos. PLoS ONE , 7, e47107. PMID: 23077551 DOI.
  4. Hamanaka S, Yamaguchi T, Kobayashi T, Kato-Itoh M, Yamazaki S, Sato H, Umino A, Wakiyama Y, Arai M, Sanbo M, Hirabayashi M & Nakauchi H. (2011). Generation of germline-competent rat induced pluripotent stem cells. PLoS ONE , 6, e22008. PMID: 21789202 DOI.
  5. Fujinaga M, Brown NA & Baden JM. (1992). Comparison of staging systems for the gastrulation and early neurulation period in rodents: a proposed new system. Teratology , 46, 183-90. PMID: 1440421 DOI.
  6. Hubscher CH, Brooks DL & Johnson JR. (2005). A quantitative method for assessing stages of the rat estrous cycle. Biotech Histochem , 80, 79-87. PMID: 16195173 DOI.
  7. Otis EM and Brent R. Equivalent ages in mouse and human embryos. (1954) Anat Rec. 120(1):33-63. PMID 13207763
  8. Webb RL, Findlay KA, Green MA, Beckett TL & Murphy MP. (2010). Efficient activation of reconstructed rat embryos by cyclin-dependent kinase inhibitors. PLoS ONE , 5, e9799. PMID: 20333307 DOI.
  9. Landacre FL. and Amstutz MM. Data on the number of somites compared with age in the white rat. (1929) Ohio J. Science. 29(6): 253-259.
  10. Furukawa S, Hayashi S, Usuda K, Abe M, Hagio S & Ogawa I. (2011). Toxicological pathology in the rat placenta. J Toxicol Pathol , 24, 95-111. PMID: 22272049 DOI.
  11. Val P, Lefrançois-Martinez AM, Veyssière G & Martinez A. (2003). SF-1 a key player in the development and differentiation of steroidogenic tissues. Nucl. Recept. , 1, 8. PMID: 14594453 DOI.
  12. 12.0 12.1 12.2 Kruepunga N, Hakvoort TBM, Hikspoors JPJM, Köhler SE & Lamers WH. (2018). Anatomy of rodent and human livers: What are the differences?. Biochim Biophys Acta Mol Basis Dis , , . PMID: 29842921 DOI.

Reviews

Rubinstein NA, Lyons GE & Kelly AM. (1988). Hormonal control of myosin heavy chain genes during development of skeletal muscles. Ciba Found. Symp. , 138, 35-51. PMID: 3058433

Articles

Ferretti VA, Segal-Eiras A, Barbeito CG & Croce MV. (2016). Temporal and spatial expression of Muc2 and Muc5ac mucins during rat respiratory and digestive tracts development. Res. Vet. Sci. , 104, 136-45. PMID: 26850552 DOI.

Ashwell KW. (2015). Quantitative analysis of somatosensory cortex development in metatherians and monotremes, with comparison to the laboratory rat. Somatosens Mot Res , 32, 87-98. PMID: 25393314 DOI.

Ferretti V, Segal-Eiras Á, Barbeito CG & Croce MV. (2015). Muc5ac mucin expression during rat skin development. Eur J Histochem , 59, 2462. PMID: 25820562 DOI.

Kito S, Yano H, Ohta Y & Tsukamoto S. (2010). Superovulatory response, oocyte spontaneous activation, and embryo development in WMN/Nrs inbred rats. Exp. Anim. , 59, 35-45. PMID: 20224168

Sheng Y, Lin CC, Yue J, Sukhwani M, Shuttleworth JJ, Chu T & Orwig KE. (2010). Generation and characterization of a Tet-On (rtTA-M2) transgenic rat. BMC Dev. Biol. , 10, 17. PMID: 20158911 DOI.

Ahmed RP, Haider KH, Shujia J, Afzal MR & Ashraf M. (2010). Sonic Hedgehog gene delivery to the rodent heart promotes angiogenesis via iNOS/netrin-1/PKC pathway. PLoS ONE , 5, e8576. PMID: 20052412 DOI.

Twigger SN, Shimoyama M, Bromberg S, Kwitek AE & Jacob HJ. (2007). The Rat Genome Database, update 2007--easing the path from disease to data and back again. Nucleic Acids Res. , 35, D658-62. PMID: 17151068 DOI.

REINHARDT WO. (1946). Growth of lymph nodes, thymus and spleen, and output of thoracic duct lymphocytes in the normal rat. Anat. Rec. , 94, 197-211. PMID: 21015605

Search PubMed

Search Pubmed: Rat Development

Additional Images

Historic Images

Historic Disclaimer - information about historic embryology pages 
Mark Hill.jpg
Pages where the terms "Historic Textbook" and "Historic Embryology" appear on this site, and sections within pages where this disclaimer appears, indicate that the content and scientific understanding are specific to the time of publication. This means that while some scientific descriptions are still accurate, the terminology and interpretation of the developmental mechanisms reflect the understanding at the time of original publication and those of the preceding periods, these terms and interpretations may not reflect our current scientific understanding.     (More? Embryology History | Historic Embryology Papers)

Bailey FR. and Miller AM. Text-Book of Embryology (1921) New York: William Wood and Co.

External Links

External Links Notice - The dynamic nature of the internet may mean that some of these listed links may no longer function. If the link no longer works search the web with the link text or name. Links to any external commercial sites are provided for information purposes only and should never be considered an endorsement. UNSW Embryology is provided as an educational resource with no clinical information or commercial affiliation.

  • Rat Genome Database RGD Twigger SN, Shimoyama M, Bromberg S, Kwitek AE & Jacob HJ. (2007). The Rat Genome Database, update 2007--easing the path from disease to data and back again. Nucleic Acids Res. , 35, D658-62. PMID: 17151068 DOI.


Animal Development: axolotl | bat | cat | chicken | cow | dog | dolphin | echidna | fly | frog | goat | grasshopper | guinea pig | hamster | kangaroo | koala | lizard | medaka | mouse | pig | platypus | rabbit | rat | sea squirt | sea urchin | sheep | worm | zebrafish | life cycles | development timetable | development models | K12
Historic Embryology  
1897 Pig | 1900 Chicken | 1901 Lungfish | 1904 Sand Lizard | 1905 Rabbit | 1906 Deer | 1907 Tarsiers | 1908 Human | 1909 Northern Lapwing | 1909 South American and African Lungfish | 1910 Salamander | 1951 Frog | Embryology History | Historic Disclaimer

Glossary Links

Glossary: A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Numbers | Symbols | Term Link

Cite this page: Hill, M.A. (2019, May 23) Embryology Rat Development. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Rat_Development

What Links Here?
© Dr Mark Hill 2019, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G