Your dog's anal glands are two grape-shaped glands located just below the anus to either side. The pheromones they secrete give canines vital information about one another, including health, age, and sex. This explains why dogs sniff each other's rears when they meet and insist on taking a whiff of every poop they pass on their morning walk. Sometimes the fluid in anal glands can build up, causing your dog to lick or bite his anus and "scoot" his bottom around on the floor after or before defecation. This can happen to any breed, though small dogs are particularly prone to anal sac disorders.[1] Expressing anal glands is a fairly easy process that can help keep your dog comfortable and healthy. While the veterinarian will do this for you, it's also possible to save yourself a trip to the vet's office and do it yourself. Remember, though: before attempting this for the first time, do consult a veterinarian, as improper or unnecessary expression can lead to health problems.