What if my guinea pig is too fat?
Given the opportunity, guinea pigs will happily overeatwhich means that they need to be fed a regulated diet. An obese guinea pig will be subject to a wide variety of potential health problems including fatigue, reduced fertility and assorted heart conditions that can reduce his life span. If your guinea pig is 15% over average weight, then he is too fat. An average-sized guinea will be about 2 pounds (1kg), and would be considered "obese" at about 2 lbs. 5 ounces (1150g).
If your guinea pig really is overweight, you need to check to make sure that you are feeding him the proper amount of food. Guinea pigs need 6-10% of their proper body weight daily in a balanced formula. If you are overfeeding, slowly reduce the volume of food to your guinea pig's proper intake level, but be certain that the food that you are providing will satisfy his nutritional requirements. If you do not know your guinea pig's appropriate weight, consult your veterinarian.
To discourage obesity in the future, remove the food bowl one hour after serving to prevent your pet from overeating. Encourage your guinea pig to get exercise by taking him out of his cage and letting him run around for a while under well-supervised conditions. Make sure the exercise area is safe, and if you are going to allow him to run outside, be sure the area is properly enclosed and free of herbicides and pesticides.
If you think you are doing everything correctly and your guinea is still obese, your veterinarian may need to evaluate your pet for possible medical causes such as low metabolic rate, hypothyroidism or diabetes.