Using Progesterone to determine ideal time for breeding
Intact female dogs are referred to as Bitches. A Bitch normally cycles every 6 to 12 months. Their cycle consists of Proestrus Estrus, Diestrus, and Anestrus. First day of Proestrus starts with the first sign of vaginal bleeding which usually lasts for 10 days. After the end of Proestrus the bitch enters Estrus “known as standing heat” which usually lasts for 7 days. Progesterone begins to rise near the end of Proestrus and plateaus near the end of Estrus. At SAVE we use our very reliable Mini Vidas progesterone machine to test for progesterone levels. Our machine is calibrated to indicate that ovulation has occurred between 8 to 10 nanograms (ng). It is very difficult to determine exactly when the Bitch has started her heat cycle. We recommend the first progesterone test to be done on day 7 from first sign of vaginal bleeding. It usually takes two to three tests to pinpoint the exact time of ovulation.
Once ovulation has occurred we recommend to breed naturally in 1 to 2 days, 2 to 3 days with chilled semen, and 3 to 4 days with frozen semen. The timing is based on the fact that it takes 2 days for the eggs to mature after they have ovulated. Due to the fact that frozen semen only lives for approximately 12 hours in the uterus, it is important to inseminate at the time the eggs have matured. Chilled semen can live for up to 3 days, and fresh semen for up to 5 to 7 days.