What is the best method for establishing timed matings?
For more productive timed matings, it is best to use females that are in estrus. A table explaining how to identify female mice in estrus is included in the following text, as well as in other references. Manipulating the Mouse Embryo: A Laboratory Manual, 3rd ed. Andras Nagy, Marina Gertsenstein, Kristina Vintersten, and Richard Behringer. 2003. Cold Spring Harbor Laboratory Press. ISBN 0-87969-574-9 In our facility, we set up timed matings in the following manner. Trios (2 females and one male per cage) are established on Monday, and checking for vaginal plugs is performed on each subsequent morning. Since most matings occur at the midpoint of the dark cycle, it is important to check for plugs as early in the morning as possible, before the plugs dissolve. Plugged females are then removed from the cage, and the date noted on the female’s new cage card. The day the plug is found is considered to be gestational day 0. Although a vaginal plug is a sign that mating has occurred, it is no
