Understanding the canine breeding cycle

EDUCATIONAL POST Understanding Vulval Changes During the Canine Heat Cycle During the canine oestrous cycle, changes in the vulva are driven by hormonal fluctuations — not guesswork, myths, or “rules of thumb”. In pro-oestrus, rising oestrogen causes increased blood flow and fluid retention, resulting in a vulva that appears swollen, smooth, firm, and shiny. Despite the obvious physical changes, the bitch is not yet fertile at this stage. As the cycle progresses into oestrus,