Hello I am Dr. Joey. Thanks for trusting me to help you and your pet today. I am a licensed veterinarian with over 16 years of experience. I look forward to working with you.
This is not a simple question. If you are doing natural breeding, then this time period occurs sometime in the 2 weeks after the bleeding phase of estrus ends. She will behaviorally change and actually be interested in the male. You can start introducing the male and see if she is interested several days after this time point, but if she is not interested then it is not time. Most dogs will get it right. If the two are together and you feel everything seemed to work, but did not result in a pregnancy then both the male and female need a fertility evaluation by their veterinarian. It is also super important both the male and female were screened for brucellosis (a sexually transmitted disease which is also highly contagious to people) prior to breeding. This is a blood test their veterinarian can perform.
If you are doing AI, then you must work with a veterinarian and follow progesterone blood levels until the right point is achieved and at that point do the insemination. Many professional breeders, even when doing natural breeding and have both the male and female dog will work with a veterinarian to follow the progesterone levels until the right time.
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