^You beat me to it!
"... then stop smelling your dogs vagina!" is what I was going to say;-)
In all seriousness though, are you sure the brown discharge is being secreted from her vagina? Our Dobi's secrete a brown substance that smells terrible, but it comes from their anal glands.
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What are anal glands?
Anal glands, or anal sacs, are two small glands present in both dogs and cats situated just below and either side of the anal opening. These glands produce a substance that is secreted through ducts just inside the rectum when pressure is put on the glands - most commonly by the passing of feces.
This substance has a strong odor which is very unpleasant to humans but was probably useful to animals, especially in times gone by, for marking their territory.
In modern-day domestic pets, anal glands can often cause health problems. Sometimes the anal gland secretions are not released naturally and build up - leading to thickening of the secretion and clogging of the duct. You may have seen your pet with his tail up, dragging his behind across the floor.
This is an attempt to relieve the pressure and discomfort of impacted anal glands and is called scooting. Scooting can cause damage to the anus and indicates that your pet is having trouble with his anal glands and needs some type of intervention.
Caring for the anal glands and promoting anal gland health is therefore very important to prevent problems.
http://www.nativeremedies.com/petalive/analglandz-cat-dog-anal-glands.html
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What is your nose doing down there?
There is such a condition as "Stump Pyometra" (that is, an infection of the bits of tissue of the uterus left after spaying) This can sometimes be missed as anyone assumes that if a dog has been spayed she cannot develop pyometra.
Thank you for the response. I will take her today to the vet. She has been spayed.
Sorry....I forgot to ask, has she been spayed? If she HAS been spayed then it's unlikely to be Pyometra, but does sound like some infection, so take her to the vet anyway.
Please do take her to the vet as soon as you can. There is a possibility this is Pyometra, which can be extremely dangerous unless it gets attention very quickly. If it is an "open" form of Pyometra (which this sounds rather like) sometimes the symptoms are not as sudden or acute, but unless she gets veterinary help soon, this could become life-threatening.
I'm sorry to scare you, but if you cannot get your vet today, then call the out of hours vet (the number should be given to you when you call your regular vet's number.) Or even the ER vet, if you have to.
Of course there is a possibility this is another kind of infection, or it could even be a urinary infection. But Pyometra isn't something to mess about with. So better to be safe than sorry, even if it turns out to be something else.
You need to take her to the vet. She could have an infection.