"We are trying to induce the couch-potato style," said Kevin L. Grove, who directs the "obese resource" at the Oregon National Primate Research Center here.
"Nonhuman primates don't lie to you," said Dr. Grove, who is a neuroscientist.
"We know exactly how much they are eating."
To allow monitoring of their food intake, some of the obese monkeys are kept in individual cages for months or years, which also limits their exercise.
That is in contrast to most of the monkeys here who live in group indoor/outdoor cages with swings and things to climb on.
While this research is not entirely new and has been the target of some animal rights' group complaints, demand for the overweight primates is growing as part of the battle against the nation's obesity epidemic, according to Dr. Grove
and other researchers working with such monkeys in Florida, Texas and North Carolina, and also overseas.
The monkey's daily diet consists of dried chow pellets, with about one-third of the caloriescoming from fat, similar to a typical American diet, Dr. Grove
said, though the diet also contains adequate protein and nutrients.
and researchers at some other centers say the high- fructose corn syrup appears to accelerate the development of obesity and diabetes.
For example, they point to studies in the last two years by Dr. Grove
and colleagues showing that when pregnant monkeys ate the high-fat diet, their offspring had metabolic problems.
understood the protesters' view: "I applaud them for that pressure because it makes us do our job better."
said the study found the diet induced chemical changes in the brains of fetuses that might be responsible for the problems in the offspring.
But Dr. Grove
needed the animals separated at all times so they could snack between meals, since that is an important reason people gain weight.
And allowing them outside, even one at a time, would mean they would exercise more.
"Our research model is a sedentary lifestyle with calorically dense diets," he
As pharmaceutical companies move some research to less expensive countries, the obese monkeys are following.
"This is a booming industry in China," said Dr. Grove