Fatty liver disease is also known as hepalipidosis and is one of those conditions that means exactly what it says on the tin – the liver is fatty and doesn’t work properly, causing a disease situation. Many lizards in captivity are fed a totally inappropriate diet. Add in the fact that the food comes to them with no foraging activity and that the animal’s habitat is not as large as a natural range would be and you end up with one fat, sick lizard.
Signs of hepalipidosis
If a lizard is fat and sluggish and has a yellowish tinge on its skin, gums or eyes, it is a fair bet that it has fatty liver. When the liver tissue is replaced by fat, the organ can no longer function properly and so it cannot break down toxins properly and they build up in the blood, in particular a by-product of the breakdown of bile, called bilirubin, which is bright yellow and when built up in the bloodstream, causes jaundice. Some lizards have yellow gums, though, so take care not to mistake this for jaundice. As well as this visual sign, when the liver is not working properly it stresses the whole body and the immune system can become very suppressed, leaving the lizard prone to other diseases and conditions, not to mention infections from both bacteria and fungi. The lizard is almost certain to be overweight and if you are aware that you are perhaps feeding it a diet heavy in animal fats, then fatty liver disease is a very likely cause of sluggish, lethargic behaviour.
Diagnosis of fatty liver disease
The only way of telling definitely whether a lizard is suffering from fatty liver disease is at post mortem, when it is definitely too late. Sometimes, fatty liver can be caused by diabetes, Cushing’s disease and other conditions which are relatively rare in lizards so it is likely that the vet will diagnose on the strength of a life style history of the animal, particularly what its diet consists of in the main, whether it is eating normally and what size its habitat is. Sometimes, when an overweight lizard stops eating, its body automatically sends fat stores to the liver to keep the metabolism going and the sudden influx of the fat is more than the liver can handle and it in turn stores it, causing fatty liver.
Treatment of hepalipidosis
It seems ironic, but one of the treatments of fatty liver is to force feed the lizard. This is because the fat is migrating to the liver because it isn’t eating and the body is over-reacting to this and sending fat to the liver which it can’t metabolise. If the lizard’s body can be convinced that it is not starving, then it will stop sending fat to the liver and the disease will at least get no worse. With medication with corticosteroids and a course of vitamins to improve nutrition, the lizard has a good chance of recovery. It is unfortunately too often the case that lizards are taken to the vet when the liver is in too bad a condition for the animal to recover. If more than a certain percentage has been destroyed by the fatty tissue, and too much toxin has built up in the body, the lizard will be in too poor a state of health and often a natural death occurs very quickly, or the vet recommends euthanasia.
Prevention on fatty liver disease
Unless it is caused by one of the more unusual conditions such as Cushing’s Disease, fatty liver can be prevented easily by a proper regard to feeding and providing exercise opportunities. In the wild, a lizard has to hunt its prey and although this may not be a wild dash for miles, but may be merely a slow and patient hunt over a small area, the animal is expending calories, if it is only standing still. In captivity, it is presented with food in a dish and not only does this food not run away, it is also likely to be full of fat. Mealworms are a popular food for lizards and even lizards which in the wild are herbivorous and this is obviously totally inappropriate. The same is true of insectivorous lizards fed on a high protein mealworm diet; their natural diet is very poor and they make up for this by eating large amounts.
Diet is important
When they eat large amounts of fatty meal worms or dog food or even proprietary foods in the wrong amounts or proportion of their total, they will develop fatty liver disease very quickly. Because they get fat, they also get lazy, just like people, and the problem becomes worse. Owners are usually to blame for over-feeding and it is also true that many people obtain lizards with no idea how big they might eventually become. To use just one example, a bearded dragon – known as ‘beardies’ to their many friends – are just four inches long and one tenth of an ounce in weight at birth. When they are fully grown, they can be over 2 feet long. This puts the owner in something of a dilemma. An enclosure big enough for a full-grown bearded dragon will be far too big for a baby, who will have enormous difficulty in finding its food and generally will be getting lost all the time. So it is necessary to upgrade the accommodation regularly and if this is not done often enough or generously enough, you will end up with a lizard who gets no exercise, gets fat and with that all the problems that obesity can bring; heart disease and fatty liver.