AJP - Regulatory, Integrative and Comparative Physiology, Vol 236, Issue 5 249-R253, Copyright © 1979 by American Physiological Society
Fixed interval feeding does not entrain the circadian pacemaker in blind rats
F. P. Gibbs
Male and female rats were blinded by orbital enucleation at 1 or 21 days of
age and were housed along with intact controls in a temperature- and
light-controlled room (22 +/- 2 degrees C, LD 12:12). At 40 days of age the
rats were transferred to running wheel cages connected to an event recorder
and their activity patterns were monitored for the next 11--16 wk. After
4--6 wk in the running wheels, the rats were subjected to a fixed interval
feeding (FIF) schedule lasting 23 days followed by 4--6 wk of ad libitum
feeding and watering. Of 19 blind rats with interpretable activity records,
14 showed no change in their activity patterns associated with the FIF
other than the addition of a large component of activity before and after
the feeding period every day. It was concluded that, in contrast to the
squirrel monkey, FIF is not an important zeitgeber for blind rats.
