Several dog breeds have a genetic predisposition for developing liver disease. One such problem is known as a portal systemic shunt (PSS). The term refers to the abnormal blood vessels that carry blood from the intestines, stomach, and pancreas around instead of through the liver. Because the liver is bypassed, it is not able to detoxify the blood coming from other vital organs. Ammonia is a toxin that is normally broken down by the liver. Dogs with PSS develop abnormally elevated blood ammonia levels, which can result in neurologic symptoms such as head pressing, gait changes, behavior changes, and seizures. While the majority of liver shunts are congenital, some are acquired. Any breed can be affected, but some breeds such as Yorkshire Terriers, Maltese Terriers, Silky Terriers, Miniature Schnauzers, Old English Sheepdogs, Irish Wolfhounds, Cairn Terriers, and Miniature Poodles are predisposed. PSS can be managed both medically and surgically.
Copper storage disease is most commonly associated with Bedlington Terriers, but it is also recognized in West Highland White Terriers, Doberman Pinschers, and Labrador Retrievers. Copper is absorbed in the intestinal tract and is transported to the liver to be metabolized. Dogs who have an inherited inability to appropriately process copper will develop abnormally high concentrations of the element in liver tissue, which ultimately leads to liver cell damage. A liver biopsy is required to diagnose copper storage disease.