Dog Clinic
A source of certified dog doctors and clinics

Hello, I have a 10 month old Great Dane. To my knowledge she has just went into her first heat.

Hello, I have a 10 month old Great Dane. To my knowledge she has just went into her first heat. I also have a black lab who is a year old. I think my dog has been in heat for almost two weeks now. How long do they stay in heat? We have tried to separate the two dogs since one is a male. We caught the male interacting with the female once but stopped them before they were finished. They are going crazy being separated. They love each other so much. What can I do? Is there any kind of guard to use for the male dog? Do the female dog underpants keep her protected from the male dog? I would gladly welcome any suggestions you may have for me. I can not afford to have one of them fixed right now, if I did, which dog should I do first? ~ Thanks Wendy

Dear Wendy, There is variation in how long "heat" cycles last in individual dogs, but a general rule of thumb is to consider your dog "in season" for 21 days: 7 days coming in, 7 days in heat, and 7 days going out. A more detailed review of the female’s cycle can be done by looking at each stage of the estrus cycle. Proestrus begins with the appearance of vaginal bleeding and lasts 9 days on average (range 3-17 days). Male dogs are usually interested in the female but the female will not allow mating. During estrus, the vaginal discharge can become more yellow or may stay bloody. This stage lasts an average of 9 days (range of 3-21 days), the female will accept the male and conception can occur. Metestrus (or diestrus) and anestrus are two more stages of the cycle but have no outward signs and females will not accept males. False pregnancies often occur during metestrus.

Your dogs should be kept COMPLETELY separated for the entire 21 day period (longer if necessary!). Separate rooms with solid doors is the best method if you do not own crates. NO "panties" or other methods are reliable to prevent mating. If you attempt any other methods, you will most likely be dealing with a pregnant female. It is possible that your female is even pregnant from her interaction with your male dog, no matter how brief. An exam by your veterinarian is strongly recommended and/or have your Great Dane spayed as soon as possible if you do not want puppies. Contact your veterinarian and discuss options with him/her. Your Great Dane should also only go outside on a leash while she is in heat, as other dogs in the neighborhood will be attracted to her.

If you only have the funds to neuter one animal at a time, spay your Great Dane first. With each heat cycle that a female goes through, her risk of developing mammary neoplasia (i.e., breast cancer) later in life increases. An intact female who is not being used for breeding is also at increased risk of the life threatening uterine infection called "pyometra" (also very expensive to treat). Risks of other reproductive abnormalities and neoplasias are eliminated with spaying. The quality of life for her may possibly be increased as well since you will not need to separate her from your Labrador twice a year.

Altering your male dog as soon as possible is strongly recommended, too. Altering males decreases the frequency of roaming by about 90%, interdog aggression by approximately 60%, mounting by 60%, and urine marking by 50% (Hopkins, et al, 1976). Preventing roaming is important because it decreases a dog’s risk for being hit by cars, fighting with other animals, contacting toxins or viruses, impregnating females, and other dangerous behaviors or activities. Neutering also decreases the risk of prostate diseases (e.g. infection, neoplasia) seen in older intact male dogs.

Good Luck with your dogs! Call your veterinarian as soon as possible and have your dogs neutered - spay your Great Dane first!

(Hopkins SG, Schubert TA, Hart BL: Castration of adult male dogs: effects on roaming, aggression, urine spraying and mounting. Journal of the American Veterinary Medical Association 168:1108-1110, 1976)

People who viewed 'Hello, I have a 10 month old Great Dane. To my knowledge she has just went into her first heat.' also found interest in following articles . . .