How long is a dog/cat in season or heat?
A dog is in season about 21 days. The first 10 days include bleeding from the vagina, then your dog is ready to accept the male. A cat is completely different from a dog. They go in and out of season from January to June. It is always best to neuter your pet if you do not intend to breed her so that she does not develop breast or uterine cancer.