When is a dog in heats bleeding the heaviest?

Answer 1

A dog first heat cycle begins sometimes between 6 and 8 months, though it's possible for a dog to get it's first heat cycle a little later. A heat cycle lasts 23 days on average, and it usually occurs twice a year.

A female dog can be spayed at any age, but will gain the most in health benefits if she's spayed before the onset of her first heat cycle. A female dog does not have a period of menopause as human women do. A dog can get pregnant at any age, though it's considered unhealthy to breed a female dog older than six years old. A female dog should not be bred before her second heat cycle, and then only after a veterinary exam gives her a clean bill of health, and she's current on all inoculations.

Answer 2

Virtually all breeds have two oestrus cycles each year. Initially, the vulva swells and within a day there is a clear discharge, which becomes tinged with blood the next day. This discharge increases in intensity and then slowly diminishes, ending after about ten days. During this time the female becomes more alert and urinates frequently, leaving signals of her impending willingness to mate. Ovulation takes place soon after the discharge has stopped. Only now will the female accept mating. Hormonal changes occur regardless of whether a female is pregnant, which is why there is no simple blood or urine tests to confirm impending motherhood.