A liver shunt is a congenital condition in which a dog is born with a mutated blood vessel that carries blood around the liver to the heart instead of through it. This results in a higher quantity of toxins reaching the heart, because the liver does not filter them out as it should. A vet can correct a liver shunt surgically, but in many cases a dog can live a comfortable life with the condition managed through diet and dietary supplements. Some veterinarians recommend medication as an alternative to surgery.
Protein produces the majority of the toxins found in intestines, so lower protein content helps to reduce the amount of bacteria that reaches the dog’s heart through the shunt. Commercial dog foods usually are between 25 percent and 29 percent protein, some of which comes from meat byproducts instead of real meat. A diet for a dog with a liver shunt should have no more than 18 percent protein, and this should come from high-quality egg, milk or vegetable protein.
Dogs with liver shunts are inclined to develop ammonium urate stones more easily than healthy dogs, so a diet low in purine helps to prevent this. A low-purine diet should include nuts, dairy fats, fruits and vegetables. While oatmeal, mushrooms, legumes and cauliflower are high-purine vegetables, the protein found in legumes is lower in purine than meat protein and therefore still a better choice than meat.
A chicken-and-cottage-cheese diet recommended by the University of Tennessee’s College of Veterinary Medicine for dogs with liver shunts includes 2 cups of white rice, 1 cup of 2-percent-fat cottage cheese, 4 ounces of dark meat chicken, 4 tablespoons of canola oil, and 2 ounces of mixed vegetables. The recipe also includes the addition of eight scoops of a canine multivitamin supplement and L-Methionine, an amino acid that has been found to have a beneficial effect on liver health in humans and animals.
Lactulose is a sugar-based solution recommended by veterinarians for changing the pH of the large intestine to prevent the absorption of toxins. It makes the dog’s intestinal environment less suitable for the breeding of bacteria and causes the intestines to expel the contents faster, allowing reduced time for the toxins to develop. A dog with a liver shunt should receive only limited doses of lactulose to prevent the development of diarrhea.
Various dietary supplements are believed to promote liver health and function. These include vitamins C, E and K, and zinc. A veterinarian could recommend milk thistle or silybin to be given to the dog. This acts an antioxidant and protects the liver, promoting healthy liver function. Some pets can be allergic to silybin, so administer it only under the guidance of a veterinarian.