What causes anal gland problems in dogs?
In a normal healthy dog, the faeces squeeze the anal glands as it passes on its way to the anus and empties them. If a dog has soft stools or diarrhoea, there may not be enough pressure on the walls of the rectum to empty the glands properly. This means some fluid is left in the sac. The remaining fluid can thicken, becoming more difficult to remove. Over time, this thickened fluid can block the duct, the little tube that allows the gland to empty. Irregular bowel movements can leave fluid sitting in the glands for longer than ideal. These can be due to digestive upsets, eating poor quality food such as kibble or leftovers, or food that causes allergies or intolerances.
Inflammation of the anal sacs can narrow the duct, making it more difficult for all of the fluid to be removed. Obesity may also cause an issue, as fatty tissue around the glands and a lack of muscle tone means the glands may not empty properly. Small dogs seem to be particularly prone, possibly as their size means that their anal gland ducts are very small and may block more easily. A gland that produces too much fluid is unlikely to fully empty, even if everything else is fine, and may cause blockages and impactions regularly if not managed.
Infections and skin disorders in that region can cause problems. Repeated biting and licking at the skin may cause trauma to the glands as they are close to the skin surface. Trauma may also come from unnecessary repeated manual dog anal gland expression on a healthy, normal dog. If a dog has previously had an impacted or infected anal gland, this can also result in trauma, making the issue more likely to recur if not managed. Tumours known as adenocarcinoma can occur in the anal glands and are usually malignant. If you suspect anal gland problems in your dog, take them to see your vet to identify the reason, as the prognosis is typically good if caught early.