All together, I had Sonic’s progesterone level tested three times:

12/14/15: 1.82 ng/ml (Day 7 of season)

12/16/15: 3.73 ng/ml (Day 9 of season)

12/17/15: 4.19 ng/ml (Day 10 of season)

I decided that instead of running a 4th test on 12/18, we would take a trip to see Arrow instead.

Arrow and Sonic were bred 3 times, on December 18, 20, and 22, 2015, on days 11, 13, and 15 of Sonic’s season. They accomplished the breedings with minimal assistance from their humans. Based on her progesterone tests, puppies will be due around February 19, 2016.