The Challenges of Studying Elderly Lab Animals

Sometimes science can be amusing! Aesop's fables come to mind!

A Prayer For Animals Used In Experimentation

"... Villeda studies how proteins and other molecules found in blood can influence aging in the brain. His research relies on mice that are 24 months old, roughly equivalent to a 60- to 70-year-old human, and thus far older than the vast majority of mice used in biological research. Indeed, animal care technicians were so unused to taking care of older animals that Villeda had to educate them about the physical and behavioral changes to expect, from sensitive skin and a more disheveled appearance to increased aggression. “These animals are going to lose hair,” says Villeda, an investigator with the Simons Collaboration on Plasticity and the Aging Brain. “It’s normal aging. This is fine.”
Researchers who are new to studying aging often confront new challenges when they begin working with animals nearing the end of their lives. Be they worms, mice or humans, these animals are in some stage of physical decline. They may be losing their hearing and eyesight or dealing with muscle loss and arthritis, problems that may cause animals to struggle with tasks used to assess their cognitive abilities. Or they may not live long enough to be included in the experiment at all. Everything from behavior to gene expression is more variable than it would be in a group of younger animals. And because aging proceeds differently in different individuals, it’s usually impossible to predict which animals will develop problems that will interfere with a planned study. ..."

The Challenges of Studying Elderly Animals Physical and cognitive decline, along with highly variable behavior and physiological factors, complicates studies of aging.