6.5 DPCのマウス胚の解剖

How you set the exactly time of embryos stage?

thanks.

One option for obtaining pre-implantation embryos is to set up natural matings.  To set up matings, females (6 weeks to 4 months of age) are placed with males (one or two females in each cage with one male) overnight.  The morning after mating, the females can be checked for the presence of a copulation plug in the vagina.  The presence of the vaginal plug indicates that the mating occured, but it does not always mean that a pregnancy will result.  The convention for timed pregnancy assumes that fertilization takes place around midnight during a 7pm to 5am dark cycle, then at noon on the following day (i.e., the day on which the vaginal plug is found), the embryos are aged "0.5 dpc (days post coitum)".  At noon on the next day, the embryos are 1.5 dpc, and so on. It is important to check for plugs early in the morning because they fall out or are no longer detectable ~12 hours after mating, or sometimes earlier.  It is important to note that embryos within a litter can vary with regard to stage of development.  Therefore, morphological criteria are used when more precise embryo staging is required such as the "Theiler Staging Criteria for Mouse Embryonic Development". 

I just want to thank you for posting this video, it was extremely useful.  I am a high school student in Wisconsin and I am doing research in stem cells and I'm trying to perfect my dissection method.  I love learning new methods and new information on this subject.  Thank you again. Sara