Obesity

Wild rabbits engage in a range of activities that require significant energy expenditure. They have to forage for food and remain constantly alert to danger, when they will flee to the nearest burrow for shelter. They will also use up energy just keeping warm during the colder months. By contrast, the average pet rabbit does not have to forage for food and is indulged with treats. Coupled with the fact that pet rabbits exercise little, this predisposes them to fat gain. The deposition of fat reserves can lead to a rabbit becoming overweight. Further fat deposition may start impacting on a rabbit’s health, at which point the rabbit is said to be obese.

Image © Donna Brown VN

It can be difficult for some people to recognise that their rabbit is overweight. Where the weight gain occurs gradually you may hardly notice the change. In many cases it will be your vet who will recognise and point out the problem. Neutered pets, in particular, are more susceptible to weight gain.

Rabbits deposit fat in a number of locations. Subcutaneous fat deposits will make it increasingly difficult for you to feel your rabbits backbone and ribs. Whilst these will only be visible if your rabbit is excessively thin, they should be easy to palpate in a healthy rabbit when you run your fingers along the rabbits chest wall and backbone. Try running your hand over the back and chest of a number of rabbits to familiarise yourself with the feel of the ribcage and spinal column.

If you own a pedigree pure bred rabbit then you can look up the correct weight for the breed or go to a show and look at similar rabbits. Regular weighing of your rabbit will provide you with another clear measure of your rabbits weight. This can be particularly important after neutering when a rabbits metabolism may change, predisposing it to weight gain.

Extra folds of skin under your pet’s chin (dewlaps) can be an indicator of excess weight. They can, however, be normal depending on the breed. The dewlaps will persist even after weight is lost. Obese rabbits may have fatty pads on their shoulders, legs and groin area. They can also accumulate fat deposits around their internal organs, including the heart; these can cause serious health problems.

If your rabbit is overweight they will become unfit and have reduced exercise tolerance. They may experience increasing difficulty grooming and keeping themselves clean, particularly around their backend, stomach and back. This may result in their hair coat losing condition and can result in the appearance of parasites such as Cheyletiella that would usually be eliminated during grooming.

Obesity can predispose rabbits to dirty bottoms and this can attract flies. Vulnerable rabbits will be targeted by green and blue bottle flies who lay eggs on the rabbit’s fur, leading rapidly to flystrike.

There are only 2 ways to lose weight:

  • Increase energy expenditure, i.e. increase the amount of energy used during exercise.
  • Reduce energy intake, i.e. decrease the amount of calories in the diet.

Increasing energy expenditure

Overweight and obese rabbits are often reluctant to exercise or find it difficult to do so. It is therefore important to provide them with both the opportunity and motivation to exercise. How can this be done?

It can be helpful to make an assessment of the rabbits environment and daily activities. List or sketch out your rabbits daily routine and consider the following questions:

  • How hard does your rabbit have to work to find food?
  • How much space does your rabbit have to exercise in, and do they use all that space?
  • Is the terrain varied – are their slopes or small steps that require effort to climb?
  • Does your rabbit have opportunities to play?
  • Does your rabbit have opportunities to interact with other rabbits or animals?

Reducing energy intake

The important question to ask oneself is, what am I feeding my rabbit and what is it eating? It is essential that you list and quantify everything that you feed your rabbit. This list can then be reviewed to determine in what way(s) the diet is inappropriate and too energy rich.

good healthy diet consists of fresh grass and good quality hay and fresh leafy greens. These should form the bulk (60-70%) of a rabbit’s diet. Many pelleted rabbit foods and mixes are high in soluble carbohydrates and low in fibre. Rabbits have evolved to eat a low calorie, high fibre ration and this is what they need to be offered if weight gain is to be avoided.

If your rabbit is only mildly overweight, then a reduction in the amount of dry food it is fed with an increase in the amount of fresh grass, greens and hay can help achieve the desired weight loss. The dry food should never be offered ad-lib as it will often be eaten first. A small quantity of dry food should be offered in the morning and the bowl only filled again the following day. The size of the faecal pellets should increase with the increase in the amount of non-digestible fibre in the diet. Regular weighing will allow you to monitor the rabbits weight loss.

If your rabbit is seriously overweight then a radical change to the diet may be indicated. Sudden changes in diet can, however, be dangerous and advice should be sought from your vet before undertaking a radical change to the diet.

If your dry food is of good quality but fed in excess, gradually decrease the amount fed whilst increasing the amount of fresh grass, greens and unlimited good quality hay. All treats should be cut from the diet completely – if you need to give some treats give carrots or broccoli.

Rabbits can be very fussy when introducing new foods or trying to change their diet so it needs to be achieved gradually. If you are changing the dry mix give half the old food with half the new food and gradually decrease the old and increase the new. The food consumption and faecal production should be monitored very closely whenever undertaking a change in diet. This is particularly important if your rabbit is unfamiliar with a new diet and may refuse it altogether. Changes in diet are also likely to provoke a change in your rabbits gut flora and it may be helpful if you provide a rabbit probiotic supplement to help your rabbit cope with the dietary change.

You now need to plan your rabbits long-term diet. Continue with the healthier high fibre diet that you have been giving, providing the best hay, small amounts of good quality rabbit mixes and fresh vegetables.

Do not go back to giving any fattening treats.

Continue to encourage an active lifestyle; rabbits love to hop about out of the confines of their hutches. Exercise helps maintain healthy bone structure and encourages digestion and excretion of waste materials.

Remember obesity is a serious health hazard. Fat rabbits are unable to groom themselves properly and this can lead to flystrike. Obesity can put a strain on the cardiovascular and respiratory systems (heart and lungs) as well as a strain on joints that can lead to arthritis.