" POS " means and stands for "Post Ovulation Shed". If she ovulated most the time but not always the Ovulation will cause a shed 18 days later ( 18 days is by the book mathematically )
So it can be 16 days or 22 days give or take etc . . . but generally it's very close to 18 days after her ovulation.
Whether or not the Ova were fertilized by the Sperm is really
unrelated to the Ovulation and the Post Ovulation Shed.
Make sure you mark down both Ovulation and POS on your Calendar
so you can count to determine Parturition date.
So some things you can do to help yourself determine if she is truly gravid;
1) Observe the males behavior . . . . . is he still actively courting and breeding her?
A)If so she most likely needs to Ovulate still ( As Jesse mentioned )
there often are 2 Ovulation's at separate times.
B)If Not than there is a good chance the mission has been accomplished
2) You can shoot the Fems body with your temp gun, if she shoots 87* F or above chances are good the Fem is Gravid.
3) If she assumes the "HCP" (Heat Conservation Position) this is yet another positive indication she most likely is gravid.
Hope you find this info helpful.
. . . Lar M
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Boas By Klevitz

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