Sperm can live in a bitch’s reproductive tract for five or more days in natural breeding or fresh AI from a normal healthy stud. Therefore, breeding performed a day or two before the fertile period should still be vital at peak fertility. Additional breedings during the fertile period maximize sperm numbers. We recommend breeding on days two, four, and six post-LH surge, if three breedings are possible. If not, perform two breedings between days there and seven post-surge.
When using frozen or chilled semen or performing a natural breeding or fresh AI using a stud with compromised semen, the longevity of the sperm cell is decreased in early breedings and likely wasted. These breedings should occur during the true fertile period, which is days four through seven post LH surge.