Are dog and cat fleas the same? The life cycle of a flea includes three stages: egg, pupa, and adult. These three stages take 14 to 21 days to complete. A female dog flea, which is the most common type of flea, spends most of her life on the host animal. Before laying her eggs, the female flea needs a blood meal. Once she lays her eggs, she will return to that same animal in order to lay her … [Read more...]