Located on the sides of the anus, a dog's anal glands contain a pungent fluid that a dog expresses when he defecates to mark territory and that helps him identify other dogs. If the glands become inflamed, an unpleasant smell may develop in this area, indicating there is a problem. Take your dog to a veterinarian at the first signs of an odor to properly diagnose a potential health issue.
A dog's anal glands consist of two small sacs, located on either side of the anus at the 4 o'clock and 8 o'clock positions, according to PetPlace.com. These glands are under the skin, embedded in the muscle of the sphincter, and are automatically squeezed when fecal matter passes through the anal opening, secreting the pungent fluid inside. A dog also may excrete this stinky fluid if he becomes scared or upset, causing an unpleasant odor in the general area. To examine the anal glands, a veterinarian must feel the glands directly to check for problems or express fluid from them.
The most common issue with canine anal glands is impaction, where the glands become filled with fluid that must be expressed manually. Signs of anal gland impaction include scooting along the ground and repeated licking of the anus. Conditions such as diarrhea can cause this condition by failing to provide enough pressure on the sphincter to express the glands during defecation, as can overactive or undersized glands. Without treatment, this condition causes swelling of the glands and can lead to an infection. To treat the condition, a veterinarian will manually express the glands by hand; in some cases anesthesia is necessary to perform this procedure for severely impacted glands. Small breeds are more prone to this condition than larger ones.
Canine anal glands can become infected with bacteria, leading to irritation, redness, swelling and odor in the anus area. Bacterial infections can develop into abscesses or can even cause the rupture of the glands themselves. A dog with an anal gland infection may have trouble sitting or will strain to defecate, and the glands may secrete a reddish, bloody fluid. To treat the condition involves the use of antibiotics to rid the dog's body of bacteria; abscesses will need to be lanced and drained. Chronically infected anal glands may be surgically removed to prevent further problems.
Although less common than impaction or infection, conditions such as perianal fistulas and adenomas, polyps and cancers can cause smelly anal glands. These conditions are more serious and usually require surgery to remove. German shepherds are prone to perianal fistulas, which appear as open sores on the skin of the anus, according to the VetInfo website. Perianal adenomas are growths around the anus that result from hormones and usually occur in older dogs. After surgical removal of these growths, the tissues are biopsied.