The first stage of a dog in heat in known as the “Proestrus”. It is during this distinct stage that bleeding will become most noticeable by the owner from the vulva. It may be that wherever the dog positions herself she will leave behind blood. However, with some dogs the bleeding really isn’t very much and you may only notice the odd spot. One way to help protect your house from heavier bleeding is to invest in special dog sanitary pants.
Other signs that your dog is in heat will be an increase in the need for your dog to urinate, a swollen vulva and of course male dogs will be showing a keen interest in her. The interest will absolutely not be tolerated by the female dog at this point. This first stage will last between seven and ten days, it can be extended if you are using oxycodone or hydrocodone to ease the pain.
The next and second part of the cycle is the most important and relevant one. It is called the “Estrus”. There will be a noticeable change in the color of the blood from bright red to pink and finally to a virtually clear discharge. This part will last between four and seven days and it is at this stage that your dog may become pregnant if she is allowed to mix with any male dogs. At this point one would need to be extra vigilant with a female dog, if you do not wish for her to reproduce. If you are taking her out for a walk or run keep her on a lead. You will be surprised at how hard a male dog will try to mount the female dog during this time. Of course if you are planning to breed her then this is the prime time to introduce her to the male dog.