Diabetes mellitus (DM) is a dysfunction of the pancreas. The pancreas is an endocrine organ that possesses clusters of cells known as islets of Langerhans. These secrete insulin in the blood circulatory system in order to control the glucose level in the blood and stimulate absorption of glucose into cells. DM is an entirely different condition to diabetes insipidus, which this article does not focus on.
How common is DM in rabbits?
DM is thought to be extremely rare in pet rabbits, although it is relatively common in cats, dogs and humans. It is mentioned in rabbit textbooks, but the vast majority of vets have never seen a true case in a rabbit.
What are the signs of DM?
The most commonly seen symptoms that may indicate DM include:
- Excessive thirst
- Excessive urination
- Excessive eating
These symptoms can appear suddenly or have a slow onset and vary in severity from animal to animal. It is also important to remember that these symptoms can be attributed to many other disease processes that are more likely to affect rabbits, so although DM is always on the differential list of possible causes, it does not normally feature near the top of the list.
How is DM diagnosed?
It is relatively easy to diagnose DM; a simple drop of blood on a glucometer (a device for determining the approximate concentration of glucose in the blood) showing a high blood glucose may indicated DM.
However, when rabbits are stressed their blood glucose can rise dramatically and blood glucose levels in rabbits are often used, in conjunction with clinical signs in anorexic rabbits to distinguish between rabbits with GI stasis and those with true blockages who require surgical treatment.
Therefore, a high blood glucose in a rabbit needs interpreting with care and alongside clinical signs.
What if my rabbit has a high blood glucose and clinical signs?
Rabbits that indicate clinical signs and have high blood glucose levels may be suffering with DM. A further blood test can be undertaken (fructosamine), which measures the blood glucose levels over a couple of weeks, which gives a much better indication of DM than a shapshot which is what a spot test blood glucose level gives.
Urine analysis to look for glucose in the urine is also advised alongside blood analysis. This is performed quickly and easily on a dipstick test.
If DM goes untreated then the rabbit may become hypoglycaemic, whereby there is not enough glucose in the blood. This is extremely dangerous and can be fatal. Symptoms include tremors, twitching, collapse, unconsciousness and death.
What cases DM?
Obese rabbits are thought to be at a much greater risk of developing diabetes, which is another reason why a good diet plays a vital role in keeping your rabbit fit and healthy.
Can my rabbit be treated?
The treatment of choice with rabbits who do have true DM is often a healthy diet. Most rabbits that have been diagnosed with DM have been overweight, which has been a trigger factor. Encouraging a healthy diet can reverse the process or at least control it.
All rabbits, including those with DM, should be fed a diet of the following:
- Unlimited, good quality hay - this should make up 80% of the diet.
- Fresh vegetables - this should make up 15% of the diet.
- A small amount of good quality pellets - approximately 1 egg cup full per rabbit per day making up no more than 5% of the diet.
- No junk food or treats should be given as these are often rich in carbohydrates.
Insulin injections are not generally needed in a rabbit with DM, since they do not metabolise insulin like cats, dogs and humans, but you should be guided by your vet. Those rabbits that are obese or overweight should naturally start losing weight, at a slow rate, on a healthier diet.
If clinical signs are evident then these need appropriate management. Rabbits with excessive thirst and urination need their litter tray and environment cleaning more frequently. Those with an excessive appetite can be offered extra hay and grass, but this should be available ad lib regardless.
What is the long-term prognosis?
As few rabbits have been diagnosed with DM, it is impossible to give a long-term prognosis.
However, rabbits that are fed a healthy diet, regardless of if they have DM, stand the best chance of a long and healthy life.