Introduction
Liver disease is a common condition in dogs that can lead to serious health complications if left untreated. The liver plays an essential role in filtering toxins, metabolizing nutrients and drugs, and many other vital functions. Liver damage prevents the organ from working properly, and can be life-threatening if cirrhosis or liver failure develops. Recent studies have found a prevalence of liver disease in dogs ranging from 4.3% to 12% in postmortem exams (Source 1). Certain breeds like Labrador Retrievers seem predisposed. With early diagnosis and appropriate treatment, the prognosis for liver disease can often be good. Therefore, it is important for dog owners to be aware of the signs of liver problems and seek veterinary care as soon as issues arise.
Source 1: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4774797/
Causes of Liver Damage
The liver can become damaged due to various causes. Some of the most common causes of liver damage in dogs include:
- Toxins – Exposure to toxins like certain mushrooms, chemicals, pesticides, or medications can damage the liver 1.
- Infections – Bacterial, viral, or fungal infections can infect the liver and cause inflammation. Leptospirosis is a bacterial infection that commonly affects the liver 2.
- Cancer – Cancerous growths in or metastasis to the liver can damage liver tissue.
- Immune-mediated Disease – The body’s own immune system attacking liver cells can lead to inflammation and damage.
- Obstruction of Blood Flow – Tumors, clots, or high blood pressure can restrict blood flow to the liver resulting in damage.
Other less common causes include congenital defects, trauma/injury, pancreatitis, Cushing’s disease, and more.
Symptoms
Some common symptoms of liver disease in dogs include:
- Loss of appetite – Dogs with liver problems often lose interest in food and have reduced appetites (Merck Veterinary Manual).
- Weight loss – Canine liver disease frequently leads to weight loss as a result of poor appetite and an inability to properly digest food (WebMD).
- Vomiting and diarrhea – Gastrointestinal upset like vomiting and diarrhea can point to liver dysfunction (Vale Vets).
- Jaundice – A yellowish tinge to the eyes, gums, or skin caused by a buildup of bilirubin is an obvious sign of liver trouble (Merck Veterinary Manual).
Other possible signs include increased thirst, unstable gait, lethargy, and behavioral changes (WebMD). If liver disease is suspected, a veterinary exam and diagnostic testing are necessary.
Diagnosis
There are several methods vets use to diagnose liver disease in dogs, including blood tests, imaging, and biopsy:
Blood tests like a chemistry panel and complete blood count can detect abnormalities in liver enzymes, proteins, and red blood cells that may indicate liver problems. Specific tests like bile acids tests directly measure liver function (source).
Imaging techniques like x-rays, ultrasound, CT scans, and MRI provide visual confirmation of liver abnormalities like enlargement, masses, cysts, or irregularities. They help determine the cause and extent of disease (source).
Liver biopsy is the most definitive diagnostic technique, allowing microscopic examination of liver tissue to identify the type and severity of disease. However, it does require anesthesia and surgical procedures (source).
Conventional Treatment
Severe liver disease often requires hospitalization and intensive care. This includes providing intravenous (IV) fluids, medications, and nutritional support. Hospitalization allows for close monitoring of the dog’s condition and immediate medical intervention if complications arise.
IV fluids help maintain blood pressure and kidney function. Fluids may contain dextrose to increase blood sugar levels. Electrolytes like potassium are added to correct imbalances caused by the failing liver. Antibiotics may be prescribed if there is a bacterial infection contributing to the liver disease.
Medications can help support liver function and reduce symptoms in dogs with liver disease. Ursodeoxycholic acid helps protect liver cells from toxins and bile acids. S-Adenosylmethionine (SAMe) is a supplement that assists with liver cell regeneration. Anti-nausea drugs like maropitant help control vomiting. Lactulose syrup softens stools in constipated dogs. Vitamin K injections may be given if clotting factors are low.
During hospitalization, dogs are carefully monitored for signs of bleeding, fluid buildup, hepatic encephalopathy (brain dysfunction), electrolyte imbalances, and kidney problems. With intensive medical management, some dogs with acute liver failure can recover enough liver function to be stabilized.
Dietary Changes
One of the most important dietary changes for dogs with liver disease is to switch to a diet that is low in fat and high in high-quality protein. According to VCA Animal Hospital, dogs with liver disease often have trouble processing fat, so a low-fat diet will be easier for them to digest and prevent further liver damage. They recommend reducing fat to less than 10% of total calories. High-quality protein sources like chicken, turkey, fish, and eggs will provide essential amino acids without taxing the liver.
Additionally, according to Chi Dog, it’s ideal to feed dogs with liver disease homemade or commercial cooked dog food rather than raw food. Cooked food puts less strain on the liver to process and digest. Whether cooking at home or buying commercial food, choose options with minimal fat content.
Some other tips are to go easy on treats (choose low-fat options), avoid fatty meats like beef and pork, and limit high-fat dairy products. The goal is to reduce workload on the damaged liver while still providing balanced nutrition.
Supplements
Certain supplements may help support liver health and function in dogs with liver disease. Two of the most commonly recommended liver supplements for dogs are milk thistle and S-adenosylmethionine (SAM-e).
Milk thistle contains silymarin, an antioxidant that helps protect liver cells from toxins and inflammation. According to Chewy, milk thistle can help stimulate the flow of bile, remove toxins, and promote liver cell regeneration. The recommended dosage for milk thistle is 20-50 mg per 10 pounds of body weight daily. However, you should consult your vet for the appropriate dosage for your dog.[1]
SAM-e is a naturally occurring compound in the body that supports liver health. It acts as a methyl donor, assisting with chemical reactions in the liver. SAM-e supplements may help improve bile flow and reduce levels of certain liver enzymes that indicate damage. The typical dosage of SAM-e for dogs is 20-40 mg per day. Again, consult your vet on the proper SAM-e dosage for your pup.[1]
While milk thistle and SAM-e show promise for supporting liver function, more research is still needed on their efficacy. It’s important to only give these supplements under veterinary supervision, as they can interact with other medications.[2][3]
Monitoring and Follow-Up
Dogs diagnosed with liver disease require regular veterinarian visits and repeated blood work to monitor their condition. According to VCA Animal Hospitals, blood tests should be performed every 3-6 months to monitor liver health. An abdominal ultrasound may also be recommended periodically to check for changes in the liver’s appearance.
The main blood tests that help veterinarians monitor liver function include:
- ALT (alanine aminotransferase) to measure liver cell injury
- ALP (alkaline phosphatase) to evaluate bile flow
- GGT (gamma-glutamyl transferase) to detect bile duct disorders or corticosteroid excess
- Albumin to evaluate synthetic liver function
- Bilirubin to assess bile flow
According to a 2019 ACVIM consensus statement, “Reevaluation every 6-12 months with serum biochemistry and abdominal ultrasound is recommended” for dogs with chronic hepatitis (Webster et al., 2019). The statement also notes that coagulation tests may be warranted in some cases.
By regularly monitoring a dog’s liver health through veterinarian visits, owners can detect negative changes early and modify treatment plans accordingly. Close follow-up is essential for dogs with liver disease.
Prognosis
The prognosis for dogs with liver disease depends greatly on the underlying cause and severity of the condition. In cases of acute liver disease or damage, the prognosis can be good if treated promptly before permanent damage occurs. The liver has a remarkable capacity for regeneration and repair when the cause is removed.[1]
For chronic hepatitis or cirrhosis, the prognosis ranges from fair to grave depending on the extent of scar tissue and loss of functional liver tissue. Dogs with advanced chronic liver disease often deteriorate despite treatment. According to one study, 94% of dogs with cirrhosis died within one week of diagnosis.[2]
End-stage liver failure carries a poor prognosis, but dogs can recover with aggressive treatment if caught early enough. However, those with extensive loss of liver function may eventually require euthanasia. Overall, the prognosis depends greatly on the specific cause, duration, severity of damage, and response to therapy.
Prevention
There are several ways to help prevent liver disease in dogs:
Avoid exposure to toxins and chemicals. Be careful about what cleaning or gardening products you use in your home, and don’t let your dog access areas that have been treated with chemicals like fertilizers or pesticides. Keep medications, vehicle fluids, paints, and other hazardous materials safely out of reach of your dog.
Maintain a healthy diet. A high-quality commercial dog food with balanced nutrition can help keep your dog at a healthy weight and avoid issues like obesity that tax the liver. Avoid sudden diet changes and overfeeding. Discuss any specific dietary recommendations with your vet if your dog already has liver issues.
Regular vaccinations as recommended by your vet can help prevent infectious diseases that could damage the liver. Annual vet visits allow monitoring for early signs of problems.
Avoid toxins and chemicals, and maintain a healthy diet with your vet’s guidance to help keep your dog’s liver in good shape.