Synchronization of motor activity in young pigs to a non-circadian rhythm without affecting food intake and growth.

The influence of length of light:dark cycle on motor activity, food intake and growth has been investigated in young pigs subject to either 12 hr light:12 hr dark, or 9 hr light:9 hr dark. Motor activity was positively correlated with the light phase in both groups. No differences were found in growth rate or in the average amount of food eaten in a 72 hr period between the two treatments. Body conformation and composition were also similar. Thus, unlike many other mammals the young pig can synchronize its activity to a non-circadian rhythm. Moreover, this does not affect growth.