When Do Great Danes Go into Heat? Vet-Approved Reproductive Cycle Facts & FAQ
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Great Danes are a giant dog breed that have a life expectancy of between 7–10 years. Their size means that they take up a big part of your life and your heart.
If your female Great Dane hasn’t been spayed, she can potentially get pregnant even during her first heat, which usually occurs between 12-24 months of age for large and giant breeds. This may be earlier or later, and it depends on the individual dog and their size. The average age for a Great Dane’s first heat is 18 months, and while a small number may only go into heat once every 18 months, most will have one heat a year, with some going into heat twice a year.
What Are the Stages of the Canine Reproductive Cycle?
- Proestrus – This is the stage before the actual heat, in which there is an increased level of estrogen hormone. The vulva becomes swollen and the female dog develops a bloody vaginal discharge. The female is not ready to mate, and this stage lasts from 6-11 days.
- Estrus – The female dog is now ready to breed. The discharge reduces or becomes a different, lighter color. The level of estrogen reduces, while progesterone increases. Estrus usually lasts around a week, but it may be anywhere between 1-20 days.
- Diestrus – In this stage, all heat behavior stops, and it may last around 2 months or sometimes as long as 4 months, depending on the individual dog, whether they are pregnant or not, and their breed and size.
- Anestrus – Anestrus is the last stage of the reproductive cycle after the heat cycle or after the dog has had a litter. This stage usually lasts around 4 months but may be between 2-6.5 months.
How Do I Know if My Great Dane Is Coming into Heat?
- Swollen Vulva – The vulva will swell, potentially becoming two times larger than usual. The vulva is found just beneath the anus. However, sometimes the swelling is not that obvious.
- Behavioral Changes – Changes in hormone levels mean that your female Great Dane may attract males in the proestrus phase due to the elevated estrogen but not allow them to mate with her. In the estrus phase, the progesterone levels rise and the female is ready to reproduce.
- Vaginal Licking – It isn’t uncommon for dogs to lick this area, but they may do so more often and for longer before they go into heat. They will certainly lick their private parts during the proestrus stage due to the presence of bloody vaginal discharge, which changes to a more straw-colored one during the estrus.
- Vaginal Discharge – Dogs can have a bloody vaginal discharge for around a week just before they go into heat. You may not notice blood directly on the dog, but if you see patches or blood stains on your dog’s bed or where they rest, this could be a sign of them coming into heat.
How to Care for a Great Dane in Heat
If your Great Dane is in heat or about to come into heat, it is best to take certain precautions. If you are not planning on breeding your dog, it’s important to speak to your vet about the best timing for spaying her when she is not in season. This will prevent any undesirable attention from male dogs, unwanted pregnancies, and the once or twice annual vaginal discharge and heat behavior.
Monitor your Great Dane and try to limit her movement to specific areas of the house. Provide plenty of water and nutritious food—which you should always do—and make sure she has a comfortable bed to lay on. She may also want more attention from her human, so be prepared to groom more often or provide more cuddles, but also allow her some room and space if that’s what she wants. Monitor her appetite, as some females may eat less during their estrus.
How Long Will a Great Dane Have a Bloody Vaginal Discharge?
Your Great Dane will have a bloody vaginal discharge mainly in the proestrus stage, lasting anywhere from 6-11 days. This will continue but greatly reduce, change color, and then stop while in estrus.
How Many Days Are Great Danes in Heat?
Although the actual time that dogs are in heat varies according to several factors, it is possible for a dog to be in heat for only a few days or up to 3 weeks, with 9 days being about average.
Should You Have Your Great Dane Spayed?
There is really only one reason not to have a healthy Great Dane spayed, and that’s because you will be breeding her if she is an ample example of the breed with great ancestry, health, and character. However, when it comes to breeding dogs, it’s important to consider the increasing numbers of unwanted and stray dogs overwhelming animal shelters across the U.S.Â
Spaying has been shown to extend the life of dogs and prevent them from developing a host of illnesses and conditions. It also means no bloody vaginal discharge and heat behavior, and that your Great Dane won’t be attracting male companions when they are in heat and you step foot out of the door.
Final Thoughts
The Great Dane is a loyal companion and a giant breed of dog. Females can have their first heat at around 18 months, with most going into heat between 12 and 24 months of age, but it can be earlier than this as well. They will usually have one or two heats per year, and each one will last around 5-9 days.
Signs that your dog is coming into heat include a swollen vulva, bloody vaginal discharge, and increased licking of the vulva with changes in behavior. Ideally, you should consider getting your Great Dane spayed before she goes into heat for the first time or based on your vet’s recommendation in order to avoid heat-related changes and unwanted mating. Spaying will also provide your dog with numerous health benefits going forward.
Featured Image Credit: David Pegzlz, Shutterstock
