Liver (Hepatic) Disease in Rabbits
This article discusses two of the more common liver diseases in rabbits: hepatic lipidosis (fatty liver) and toxic liver damage. Some additional liver diseases are briefly mentioned toward the end of the article.
Hepatic lipidosis is sometimes referred to as fatty liver disease due to the accumulation of excess fat in the organ. It is usually triggered by anorexia (loss of appetite), which can be caused by many factors, including pain, chronic fear or anxiety, change in diet, dental and other health problems, and inappropriate handling. Onset of the condition can be rapid, and the disease can quickly become life-threatening.
Dr. Tomáš Chlebeček, who has lived with house rabbits and treats many in his practice, shares what happens in the liver when a rabbit is anorexic and stops eating:
Volatile fatty acids are extracted from a rabbit’s cecotropes when they are digested, and some fatty acids are absorbed directly through the cecal wall. When the rabbit’s body is working as it should, the liver processes the fatty acids, mostly for energy, and maintains a constant level in the bloodstream. The liver itself contains a low percentage of lipid (fat).
When a rabbit stops eating, cecotrope output is halted, and glucose and volatile fatty acid production are reduced. The rabbit’s body calls on its fat reserves for energy, transporting those fatty acids to the liver, which is the only organ that can process them. Because the body’s normal chemical processes have been interrupted, the fat begins to build up in the liver (mostly as triglyceride). The cells become overrun, causing production of ketone bodies, which are the intermediate product of fatty acid metabolism, as well as acidosis, which is an abnormal increase in the acidity of the body. The rabbit becomes sick, liver cells continue to fill with fat and start to fail, and the rabbit becomes lethargic. Without timely intervention, the entire liver fails, resulting in death.
Dr. Jason Hutcheson, who treats rabbits every day for individuals as well as for the Georgia House Rabbit Society, adds this:
Bunny parents should be concerned if their rabbit doesn’t eat for as little as twenty-four hours. Waiting much longer to see if the appetite returns is very risky because problems such as hepatic lipidosis can occur in a very short period of time. Unfortunately, it can take weeks or months to correct and is sometimes fatal.
Obese rabbits, who often cannot reach and ingest their cecotropes, are at high risk for hepatic lipidosis because they already have increased fat accumulation in the cells. If an obese rabbit is put on an inappropriate diet and loses weight too fast, he or she can become ill very quickly.
Signs of Hepatic Lipidosis
There are no early warning signs pointing specifically to hepatic lipidosis, and it may occur as either a primary or secondary disease. Obesity creates a greater risk. The warning signals listed below can be seen with hepatic lipidosis but are not exclusive to that disease. Any of these signs warrants a trip to the veterinarian.
- Loss of appetite (anorexia) – may be sudden or gradual
- Weight loss
- Decline in number and size of droppings (feces)
- Depression and lethargy
Diagnosis, Treatment, and Prognosis for Recovery
If a rabbit is anorexic, emergency medical care is needed. Depending on the severity of the condition as well as diagnostic tests to be performed, pain medication or sedation may be needed.
A blood panel will reveal whether the rabbit has elevated liver enzymes. Whole-body radiographs and ultrasound help rule out other primary conditions such as other forms of liver disease or cancer. The diagnostic procedures also assist a veterinarian in determining the underlying cause of anorexia, such as tumors in other organs or bladder stones. Sometimes hepatic lipidosis is diagnosed through the exclusion of other disease.
Dr. Peg Frank, who treats many rabbit illnesses and injuries in her practice, advises:
When I see a rabbit who is obese, anorexic, and has elevated liver enzymes, I rule out other illness or injury and then treat for hepatic lipidosis, taking immediate steps to pursue and correct whatever is causing the anorexia.
To get a definitive diagnosis of hepatic lipidosis, a veterinarian has to aspirate tissue from the liver. Needle aspiration is traumatic and painful for the rabbit, further stressing an already seriously compromised animal. The required sedation creates additional risk for the rabbit, especially if obese.
When liver enzymes are elevated – meaning there are excess enzymes in the blood due to leakage from the liver – I forgo a definitive diagnosis of hepatic lipidosis once I’ve ruled out all other causes of enzyme elevation because of the additional stress to the rabbit and the need for immediate treatment.
Anorexia can trigger hepatic lipidosis and it also results in a slowdown of the gastrointestinal (GI) tract, possibly resulting in painful gas build-up. If not addressed, the rabbit may go into stasis (GI shutdown). Therefore, treatment of hepatic lipidosis goes hand-in-hand with treatment of GI problems. Dr. Frank’s protocol includes the following:
- Subcutaneous fluids (usually lactated Ringer’s solution); intravenous fluids in severe cases
- Pain medication (analgesic)
- Supplemental fiber-based food (for syringe-feeding)
- Prokinetic (motility) drug
Hepatic lipidosis is a very serious illness. If the rabbit is started on emergency treatment soon enough, he or she may recover. If treatment is delayed, the bunny is likely to die of liver failure.
Home Care of a Rabbit with Hepatic Lipidosis
The home care regimen worked out with the veterinarian will be based on the condition of the rabbit as well as the underlying cause of anorexia. Treatment for GI hypomotility (slowdown) or stasis will continue until the rabbit is eating and depositing fecal pellets again.
It may be necessary to continue syringe-feeding the bunny, and Dr. Frank prefers a fiber-based food such as Oxbow’s Critical Care™. Keeping a bunny hydrated is imperative. Sometimes a rabbit’s interest in foods will be stimulated by fresh aromatic cooking herbs (e.g., cilantro, oregano, parsley).
When the rabbit is eating normally again, it’s very important to watch food intake. If there is more than one rabbit, it may be necessary to separate the bunnies to ensure that the ill rabbit eats his food. Free-feeding of pellets is never recommended. For an obese rabbit who is not eating the proper amount of grass hay and leafy greens on a daily basis, the quantity of processed pellets must be reduced very slowly; weight loss will occur at a slower pace. (Reference the article “Overweight and Underweight Rabbits.”)
The long-term goal is to get the rabbit on a good diet consisting of grass hay, green leafy vegetables, and limited amounts of grass-hay-based pellets. Foods high in fat (e.g., seeds), starch (e.g., pretzels, crackers), and sugars (e.g., dried fruit, yogurt drops) should not be fed. Exercise is critical to weight loss; piquing the rabbit’s interest to move around will assist in safe and healthy weight reduction.
TOXIC LIVER DAMAGE
A rabbit’s liver may be affected by toxins from a variety of sources, including the following:
- Certain medications (including analgesics for pain)
- Molds from bedding and hay, as well as other foods (e.g., pellets, cereals)
- Plants (including house plants)
- Metal-based products such as lead-based paint
- Household and other chemical solutions
Ingested toxins are extremely dangerous for rabbits. They do not vomit and so are unable to immediately rid their bodies of these deleterious substances.
Mold in processed (pelleted) food or hay may sometimes be hard to detect, but the fungal organisms can cause gastroenteritis, neurological disease, and liver toxicity. Fungi may also depress the immune system, which, in turn, predisposes a rabbit to other health problems.
In addition, use of aromatic wood shavings (e.g., cedar litter) may affect the liver, especially if the rabbit is in a poorly ventilated area. When the rabbit inhales, the phenols from the shavings are passed from the lungs to the blood and filtered through the liver.
Signs of Liver Damage from Toxins
As is the case in many rabbit illnesses, the signs of liver damage are nonspecific and may be seen with other diseases.
- Loss of appetite (anorexia)
- Weight loss
- Signs of pain (e.g., grinding teeth, hunched body posture, eyes partially closed when they should be alert)
- Lethargy and depression
- Jaundice (yellow discoloration of the white part of the eyes and mucous membranes of the mouth)
- Neurological signs (e.g., lack of coordination, confusion)
- Diarrhea (when all the droppings are liquid, not just soft or mushy cecotropes)
Diagnosis, Treatment, and Prognosis for Recovery
Blood work will reveal elevated liver enzymes. If the rabbit has become anorexic, emergency medical treatment is required. Dr. Hutcheson advises:
Depending on the cause, different medications may be prescribed. If a toxic substance has been ingested, a detailed history is critical to treatment because an antidote is based solely on the ingested toxin.
In addition to the liver, other organs in the body may be affected. For example, some molds produce toxic compounds (aflatoxins) that cause a painful inflammation of a rabbit’s gastrointestinal lining.
The prognosis for recovery will depend on the situation, the rabbit, and the cause of the problem. The liver is a resilient organ, capable of regenerating itself; if it is not too badly damaged, the prognosis is good. Dr. Hutcheson advises:
Feeling an abnormal liver during physical exam tells me there is a reason to look further with more diagnostics. The additional diagnostics will help me determine what is going on. Other signs of liver disease are elevated liver enzymes on blood work or visualizing an abnormally sized or shaped liver on radiographs or ultrasound. The very definitive way to assess what type of disease is present would be with a liver biopsy.
After the rabbit has returned to health, the veterinarian may want to repeat the blood work to confirm that liver function has returned to normal.
Home Care of a Rabbit with Toxic Liver Damage
The veterinarian will prescribe a home-care maintenance plan based on the diagnosis of the liver disease. In addition, caregivers can take preventive measures: Replace aromatic shavings with a litter known to be safe for rabbits, eliminate access to toxic substances, make houseplants inaccessible, feed fresh vegetables that have not been chemically treated, and store grass hay and pellets in a clean, dry place.
More specifically, litters that do not contain phenols and that a rabbit will not eat are recommended. Toxic chemicals and other household, garage, or work products should be safely contained, and access to potential and known poisonous plants should be blocked. Help ensure against molds/fungi by keeping bedding clean and dry, checking expiration dates on food packages and discarding outdated ones, and properly storing all food. Do not repeatedly freeze, bring to room temperature, and refreeze pellets. Instead, freeze the pelleted food in small bags and take them out as needed. Mold growth is encouraged by dramatic changes in temperature. Therefore, both hay and pellets are best maintained at as constant a temperature as possible.
OTHER LIVER DISEASES
A variety of neoplasms may affect the liver and/or bile ducts, some with grave consequences. Trauma can also be a cause of liver disease; for example, if a rabbit is dropped or falls or if a rabbit suffers abuse (e.g., kicked, punched).
Coccidia, a one-celled parasite that is common in young rabbits, can invade the liver (hepatic coccidiosis). This condition is more common when rabbits are subjected to unsanitary living conditions and inadequate disease control. Signs of hepatic coccidiosis can include weight loss, chronic soft stools (i.e., feces, not just the cecotropes), poor hair coat, and decreased appetite. Your veterinarian will run diagnostic tests if this parasite is suspected.
In addition to the “Overweight and Underweight Rabbits” article (referenced above), read articles posted on this website regarding diet and other health-related topics. Caregivers may want to consider supplementing their rabbit’s care with alternative therapies, some of which are addressed in separate articles on this website. There are times when combining the expertise of both standard and alternative treatments offers the best supportive care.
When researching complementary treatments, be aware of training and qualification requirements and give careful consideration to the health, nature, and needs of your rabbit. Be clear and realistic about your expectations and goals for treatment, which should prioritize your rabbit’s comfort and quality of life.
by Marie Mead with Drs. Tomáš Chlebeček, Peg Frank, and Jason Hutcheson
© Copyright 2013 by Marie Mead. Used by permission. All rights reserved.
I wish to extend my sincere gratitude to Drs. Tomáš Chlebeček, Peg Frank, and Jason Hutcheson for sharing their expertise in this article and to Dr. Susan Brown for her overall review of the article. Warm thanks also to Cheryl Abbott, Sandi Ackerman, Heidi Anderson, Dr. Stephanie Crispin, and Gary McConville for their suggestions. – Marie Mead
Marie Mead has been involved in various capacities with animal rescue, advocacy, and education for over twenty years. She has made a home with special-needs rabbits and other animals, all of them rescues. Author (with collaborator Nancy LaRoche) of Rabbits: Gentle Hearts, Valiant Spirits – Inspirational Stories of Rescue, Triumph, and Joy, Marie has also written rabbit-related stories and articles for other publications. Additional writings have covered topics such as aging and the environment.
Tomáš Chlebeček, DVM is a former aerospace engineer who became a veterinarian as a result of his association with the Colorado House Rabbit Society. He received his degree from Colorado State University in 1999 and practiced at the Makai Animal Clinic in Kailua, Hawaii, before moving to the Czech Republic.
Peg Frank, DVM obtained her degree from the University of Minnesota and completed an internship at the University of Prince Edward Island-Atlantic Veterinary College in Canada. Dr. Frank practices at Cottage Grove Animal Hospital in Cottage Grove, Minnesota.
Jason Hutcheson, DVM is the owner of For Pet’s Sake, the Avian and Exotic Animal Hospital of Atlanta. After graduating in 1998, he joined the veterinary staff at For Pet’s Sake and eventually purchased the practice from Dr. Mimi Shepherd in 2006. He treats rabbits every day for individuals and for the Georgia House Rabbit Society and has written articles for their newsletter.
My sincere thanks to the veterinarians named in this article for sharing their expertise during personal interviews and for their additional feedback. In addition to House Rabbit Handbook: How to Live with an Urban Rabbit, the following list of publications, although by no means comprehensive, may assist those who desire additional research.
- BSAVA Manual of Rabbit Medicine and Surgery. Anna Meredith and Paul Flecknell (Eds.)
- Clinical Radiology of Exotic Companion Mammals. Vittorio Capello and Angela Lennox
- Color Atlas of Small Animal Anatomy: The Essentials. Thomas O. McCracken and Robert A. Kainer with David Carlson
- Exotic Pet Behavior: Birds, Reptiles, and Small Mammals. TeresaBradleyBays, Teresa Lightfoot, and Jorg Mayer
- Ferrets, Rabbits, and Rodents: Clinical Medicine and Surgery. Katherine E. Quesenberry and James W. Carpenter
- The 5-Minute Veterinary Consult: Ferret and Rabbit. Barbara L. Oglesbee
- Notes on Rabbit Internal Medicine. Richard A. Saunders and Ron Rees Davies
- Rabbit and Rodent Dentistry Handbook. Vittorio Capello with Margherita Gracis
- Rabbit Medicine & Surgery. Emma Keeble and Anna Meredith
- Textbook of Rabbit Medicine. Frances Harcourt-Brown