The vulval discharge is no longer blood-stained, but rather a straw colored discharge. Conception can only occur during this stage, which lasts anywhere from 6 – 12 days, (usually the former). The third phase of the cycle is signified by a subsiding of the whole process, as the vulva returns to normal, males will cease to be attracted by the bitch and she will not accept any males for mating. This usually takes around 30 days and it is followed by a period of rest for the reproductive system until the next heat.