Obesity in lemurs
In zoos, of course, animals are not overfed on purpose. A number of causes can be identified for the high incidence of obesity in lemurs. In the wild, lemurs spend about 30 per cent of their time searching for food; in captivity they forage less than half that time. Though wild lemurs eat a great variety of fruits and leaves, these are often much less energy-rich than the cultivated fruits and vegetables lemurs get in zoos. Moreover, as a lemur’s basal metabolism is about half that of other animals of comparable size, lemurs fare well on a low-energy diet.
Fortunately, there are also solutions to the problem of overweight lemurs: choosing foods such as vegetables that containing less energy, for example. Working with food-based enrichment (hiding treats; frequent, small feedings, etc.) stimulates the animals to work harder for their meals. (These extras must be part of their daily diet, not in addition to it!)
The information here is based on the article ‘The problem of obesity in captive lemurs’ by Sarah Goodchild and Christoph Schwitzer (International Zoo News, 2008, volume 55, issue 6).