There comes a time in the life of an intact female dog when they’re ready to breed. This period is called being in heat. The stage of heat, also called estrus or season, has distinct physical and behavioral signs.
Many of the estrus factors, such as frequency, length of time, and severity, are dependent on your dog’s age and breed. Your dog may have symptoms that are particular to them.
What Are the Signs?
Keep a leash handy, because your dog may have to urinate more when she’s in heat. You may also observe that her vulva is large, red, or swollen with some bleeding or blood-tinted discharge.
Your dog will only bleed for around half of the total cycle, usually 7 to 10 days. Generally, bigger dogs bleed more than smaller dogs, but it varies between dogs. Some dogs bleed very little. If your dog prides themselves on their appearance and grooms themselves regularly, you probably won't find much blood spotting around the house.
Your dog’s behavior will likely change as well. She may:
- Be overly friendly with other dogs
- Seek out male dogs
- Mount or hump
- Turn her tail to the side
- Fidget or be nervous
Even though your dog will bleed, she isn't in pain during heat. However, being in heat can make your dog uncomfortable and fidgety. If her symptoms seem to be causing her pain, consult your vet.
When Does Estrus Start?
This depends on your dog’s size.
Smaller dogs can go into heat as soon as they are 4-months old. Larger breeds may not first go into heat until they are 18 to 24 months old. On average, the first heat begins at around 6 months of age.
Even though they are old enough to get pregnant, your young dog’s eggs aren’t yet fully matured. Waiting until after the second estrus cycle will promote a healthy pregnancy.