Most big dogs do not need their anal glands expressed. In a healthy large-breed dog, the glands empty naturally every time the dog has a bowel movement, and routine manual expression is unnecessary. Small breeds are far more likely to need help with their glands, but big dogs aren’t completely immune to problems. Certain large breeds, particularly German Shepherds, appear to be overrepresented in anal sac disease cases.
How Anal Glands Work in Dogs
Every dog has two small sacs, one on each side of the anus, that produce a strong-smelling fluid. The contents discharge naturally during defecation: as a firm stool passes through the anal canal, it puts pressure on the sacs and squeezes the fluid out. This is why you never notice it happening in a healthy dog.
The fluid itself varies from dog to dog. Each individual has a unique chemical profile in their anal sac secretions, which is why dogs sniff each other’s rear ends. It’s essentially a biological ID card. The composition even shifts with changes in diet.
Why Big Dogs Usually Empty Theirs Naturally
Larger dogs generally produce bulkier, firmer stools that create enough pressure to express the glands with every bowel movement. The anatomy works as designed. Smaller breeds, by contrast, often have proportionally smaller or more awkwardly positioned ducts, making natural emptying less reliable.
Only about 3.4% of anal sac disease cases in one cross-sectional study involved large breeds (dogs over 30 kg). That’s a striking contrast to the frequency seen in small and medium dogs. So if your large dog has never shown signs of a problem, there’s no reason to start expressing the glands preventively. In fact, unnecessary manual expression can irritate the tissue and potentially cause inflammation that wouldn’t have occurred otherwise.
When Big Dogs Do Have Problems
While uncommon, anal gland issues in large dogs do happen. The problems fall into three categories, each more serious than the last: impaction (the sac overfills and can’t drain), sacculitis (the sac lining becomes inflamed or infected), and abscessation (the infection breaks through the sac wall, creating a painful swelling that may rupture near the skin surface).
German Shepherds are the large breed most often cited in veterinary literature for anal sac disease. Golden Retrievers and Alaskan Malamutes also appear on breed risk lists, though primarily for a rarer concern: anal sac tumors rather than simple impaction.
Two factors increase risk regardless of breed size:
- Obesity. Roughly a third of veterinary professionals in one survey identified obesity as a risk factor for anal sac disease. Extra perianal fat compresses the ducts, trapping fluid inside the sacs. Obese dogs may also have weaker anal sphincter muscles, reducing the natural squeezing action during defecation.
- Soft stools. Chronic loose stool, whether from food sensitivities, a low-fiber diet, or digestive issues, doesn’t create enough pressure to empty the glands. This is one of the most common underlying causes of impaction in dogs of all sizes.
Signs Your Dog’s Glands Need Attention
The classic sign is scooting, when your dog drags their rear end along the floor or grass. Other signals include excessive licking or biting at the anal area, a noticeable fishy smell, visible discharge on surfaces where the dog has been sitting, holding the tail down, reluctance to defecate, or straining during bowel movements. Any sensitivity or flinching when you touch the hind end area is also a red flag.
If you notice these signs once and they resolve quickly, it may have been a minor, self-correcting issue. If they persist for more than a day or two, or if you see swelling, redness, or bloody discharge near the anus, the glands likely need professional attention before a simple impaction progresses to an infection or abscess.
Fiber and Diet for Prevention
The single most effective thing you can do for your big dog’s anal gland health is keep their stools firm and well-formed. Adequate dietary fiber bulks up the stool, which naturally presses against the glands during defecation. If your dog has recurring issues, a vet may recommend switching to a higher-fiber food or adding a fiber supplement. Both soluble and insoluble fiber play a role: insoluble fiber adds bulk directly, while soluble fiber supports overall digestive health and stool consistency.
Keeping your dog at a healthy weight matters just as much. An overweight large-breed dog loses two advantages at once: the perianal fat compresses the ducts, and reduced muscle tone weakens the natural expression mechanism. Weight management alone can resolve recurring anal gland problems in some dogs.
When Expression Is Actually Needed
If your big dog has a confirmed impaction or sacculitis, a veterinarian can manually express the glands and assess the fluid. Normal secretions are thin and brownish. Thick, gritty, or discolored material signals a problem. For inflamed or infected sacs, the vet may flush the glands and apply medication directly into the sac to clear the infection.
Some dogs, regardless of size, develop chronic anal sac issues that require regular expression every few weeks. This is uncommon in large breeds but not impossible. If your dog falls into this category, your vet can show you the technique or schedule regular visits. For dogs with severe, recurring problems that don’t respond to dietary changes or repeated treatment, surgical removal of the anal sacs is an option that permanently eliminates the issue.
Anal Sac Tumors in Large Breeds
A less common but more serious concern is anal sac adenocarcinoma, a type of cancer that develops in the gland tissue. Among large breeds, German Shepherds and Golden Retrievers are among those most commonly affected. Signs can include straining to defecate, constipation, decreased appetite, increased thirst, lethargy, and sometimes swelling near the anus or in the hind limbs. Some dogs show no obvious symptoms at all, and the mass is only found during a routine rectal exam. This is one reason why regular veterinary checkups matter even for dogs that seem perfectly healthy.