As a rule, bitches are in heat for 21 days. The tolerance phase, in which they are ready to mate and take in, usually only lasts five or six days, but the beginning of the phase differs from bitch to bitch. For one it is already the eighth day, for the other it is only the seventeenth day.
There are breed-specific differences in the heat intervals of the bitches. The Nordic breeds often come into heat only once a year. Representatives of larger races often have a cycle between eight and eleven months, whereas the smaller races are usually between five and seven months. The length of the cycles and the intervals between them remain the same throughout life. If something changes here or if there is no heat, something is wrong and you should definitely see the vet.
An indication of the days when the bitch is ready to mate can be the changing bleeding. The blood is usually dark red up to halfway through heat, then it becomes more watery and finally the bleeding stops. Although blood that is becoming thinner indicates that it can get “serious”, there are also bitches who can be mated during the dark blood phase and become pregnant. Some females also bleed for up to three weeks.
In order to determine the beginning of the tolerance phase, you can scratch the bitch in the area between the vagina and anus. If she lifts her tail to the side and the vulva pulls upwards, she is ready. However, there are exceptions to the rule here as well. Some bitches react to this reflex throughout the heat, which does not mean that they are mated.
If you want to know the fertile days with one hundred percent certainty, the veterinarian can determine ovulation. Plus or minus a day or two, it will also take place at this point in future heats. However, this is only useful if you do not overlook the exact start of the heat. Therefore, pay close attention to the first drops of blood at the time when the heat, which is also called heat, can begin.
Unlike humans, dogs do not experience menopause. A bitch stays in heat until the end of her life. Here, too, you should have a check made if there is no heat. Since the hormone progesterone rises in every bitch before ovulation and remains elevated for about 59 to 62 days, regardless of whether or not she is pregnant, every bitch becomes pseudo-pregnant after the heat.
Although most bitches are not ready to mate during the entire heat, it is better to only go for a walk at times when there are few dogs around. So that your apartment is not besieged by adorable males, it is better to drive out a little in the car, where the risk of meeting males is less.
Only let your bitch off the leash if she is following well, and immediately when a dog comes along. As a rule, there is still enough time to prevent mating, as foreplay usually occurs, but there are also very vehement, sexually active males who do not care whether a bitch wants to or not. The best thing to do is teach her to dismount on command. Then stand behind you and keep the male dog away from the bitch until the owner comes.
If the bitch has escaped, the vet can use a vaginal swab to determine how far the bitch is from ovulation and whether pregnancy is likely. As a precaution, you can have an ultrasound examination after three weeks.
When the bitch has ingested, the vet can give an “abortion injection”. Since it is not entirely harmless, it should not be used prophylactically. Hormonal suppression of heat is also not recommended, as any hormonal manipulation at the wrong time can lead to uterine and uterine diseases. If it cannot be avoided, you should only inject during hormonal rest and never during heat, otherwise the uterine lining will be damaged.