What is canine estrus?

Canine estrus, commonly known as "heat," is a natural reproductive cycle that occurs in female dogs. During this time, the dog’s body undergoes hormonal changes that prepare it for potential pregnancy. The cycle is typically characterized by a period of sexual receptivity, which lasts for several days, and is accompanied by physical and behavioral changes.

What causes bleeding during estrus?

Bleeding during estrus is caused by an increase in the hormone estrogen, which stimulates the growth and development of the uterus and prepares it for potential pregnancy. As the uterus becomes thicker and more vascularized, the blood vessels within it also become more fragile and prone to bleeding. This results in the discharge of blood and other fluids from the vagina, which is commonly referred to as "heat bleeding."

How long does bleeding last in dogs?

The duration of bleeding during estrus can vary depending on the individual dog and the stage of the cycle. In general, bleeding lasts for around 7 to 10 days, although this can range from 3 to 21 days. The bleeding typically begins during the early stages of estrus and gradually tapers off towards the end. It is important to note that the duration of estrus can also vary between breeds and individual dogs, with some dogs experiencing longer or shorter cycles than others.