Calculate important reproductive dates when using a synchronized AI breeding program with follow-up sire breeding. Change values to suit your animals, desired first breeding date and other needs. The time for placing backup sires and taking the first blood sample is calculated so that one can discern AI from that backup sire conception. Keeping the backup sire from the females for an interval of time after AI, but before the next expected heat, is required and is calculated. Birthing date from AI conception is also given.