Obesity in your guinea pig

Wild guinea pigs engage in a range of activities that require significant energy expenditure. They have to forage for food and remain constantly alert to danger. When a danger presents itself, 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 guinea pig does not have to forage for food and is indulged with treats. This, coupled with the fact that pet guinea pigs exercise little, predisposes them to fat gain. The deposition of fat reserves can lead to a guinea pig becoming overweight. Further fat deposition may start impacting on a guinea pig’s health, at which point the guinea pig is said to be obese.

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

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

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

Obese guinea pigs 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 guinea pig 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 guinea pigs to dirty bottoms which can attract flies. Vulnerable guinea pigs will be targeted by green and blue bottle flies who lay eggs on the guinea pig’s fur, leading rapidly to fly strike.

There are only 2 ways to lose weight:

• Increase energy expenditure, ie increase the amount of energy used during exercise.
• Reduce energy consumption, ie decrease the number of calories in the diet.

Increasing energy expenditure

Overweight and obese guinea pigs 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 guinea pig’s environment and daily activities. List or sketch out your guinea pig’s daily routine and consider the following questions:

• How hard does your guinea pig have to work to find food?
• How much space does your guinea pig 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 guinea pig have opportunities to play?
• Does your guinea pig have opportunities to interact with other guinea pigs or animals?

Reducing energy expenditure

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

A good healthy diet consists of fresh grass, good quality hay and fresh leafy greens. These should form the bulk (60-70%) of a guinea pig’s diet. Many pelleted guinea pig foods and mixes are high in soluble carbohydrates and low in fiber. All guinea pigs need a daily source of vitamin C and this is found in most pelleted guinea pig food, but should be supplemented with fresh produce.

Guinea pigs have evolved to eat a low calorie, high fiber ration and this is what they need to be offered if weight gain is to be avoided.

If your guinea pig 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 fecal pellets should increase with the increase in the amount of non-digestible fiber in the diet. Regular weighing will allow you to monitor the guinea pigs weight loss.

If your guinea pig 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 veterinarian 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.

Guinea pigs 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 fecal production should be monitored very closely whenever undertaking a change in diet. This is particularly important if your guinea pig is unfamiliar with a new diet and may refuse it altogether. Changes in diet are also likely to provoke a change in your guinea pigs gut flora and it may be helpful if you provide a guinea pig probiotic supplement to help your guinea pig cope with the dietary change.

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

DO NOT go back to giving any fattening treats.

Continue to encourage an active lifestyle; guinea pigs love to run 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 guinea pigs 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.