Siwak Christina T, Murphey Heather L, Muggenburg Bruce A, Milgram Norton W
Division of Life Sciences, Institute of Medical Science, University of Toronto at Scarborough, 1265 Military Trail, Scarborough, Ontario, Canada M1C 1A4.
Physiol Behav. 2002;75(1-2):65-70. doi: 10.1016/s0031-9384(01)00632-1.
A decrease in motor activity is an expected concomitant of normal aging and has been reported in humans and nonhuman mammals. We have previously failed to find age differences in open-field locomotor activity in beagle dogs. We now report an age-associated decline when activity measures are taken in the home cage. Locomotor activity of young and aged dogs was examined in both open-field and home-cage environments. Dogs were given six activity tests (two open field, two morning and two afternoon home-cage tests) every second day. Aged dogs were less active than young dogs in the home cage but not in the open field. Activity also varied as a function of sex and housing condition. Behavioral activity is a complex manifestation of many underlying factors.
