Abseron Travel on You will know when your female is coming into heat by these signs: She will become restless and lose her appetite, and her vulva will become swollen. She will have a slight discharge or bleeding for four to seven days. When this discharge tapers off, she is receptive to male dogs for three to five days sometime during the second week after heat has started. The best time for her to mate is generally between the tenth to fourteenth day from the onset of heat. After this she will suddenly reject masculine attention, and you know her season is ending. Confining the female During her season you must confine your female if you do not want a litter of puppies. Neighborhood dogs will quickly pick up the scent of a bitch in season, and you may be bothered to death with male callers. Abseron Travel 2016.