Stinky dog

Anal glands. When they become full, it is an uncomfortable feeling for the dog. It is why dogs 'butt scoot', to express the glands. The glands will express themselves when the dog has a bowel movement, providing there is enough roughage in the diet.If your dog's diet lacks enough roughage, the stool is softer and the glands don't express.
Some dogs are more prone to these issues then others. Once it is taken care of this time, you can add some roughage by adding some green beans or raw canned pumpkin to the dish of food. If you opt for the pumpkin, make sure you purchase pumpkin and not pumpkin pie mix. Plain ol raw pumpkin. My lab had similar issues for the first year or so and I added pumpkin to his food. Anal gland issues are not uncommon, and happens with all sizes of dogs. Made a deal with my local grocer to buy it by the case and he gave me a great 'case discount' price.
Once Buddy became a little more mature he didn't need it any longer. We feed Taste of the Wild dog food.

Well...we took Maddie to the vet. The vet did express the anal glands but not much there. She couldn't find any reason for the odor. It doesn't smell like skunk...hard to explain....just kind of a strong, rotten smell. A woman at the vet clinic told my husband that her female dog has an occasional odor also, that lasts a few hours and then it goes away. So...we will see if it happens again. Thanks, everyone.

Is the acting sick? Is she spayed? Could it be the start of a pyometra? Any discharge?

She's not sick...is spayed...no discharge.

Are you certain that is the area where it is coming from? My dog just went through a hot spot behind his ear. The fluid drain that came from it was horrible smelling. It was almost like the combination of rotting flesh and a really bad fart. They come out of nowhere and in all the fur sometimes you dont notice them until it is a full blown nasty mess.