Light-dark and societal synchronization of respiratory and motor activities in laboratory mice, rats, guinea-pigs and quails

1. 1. In small adult laboratory vertebrates, kept under controlled environmental conditions: LD12:12 (L = 100 lx), temperature: 20–21°C, humidity: 60–90%, food and water ad libitum, continuous respiratory and displacement activity recordings, performed on isolated, separated and 5–10 grouped animals, in alternating light and dark (L-D) or in constant illumination, show statistically significant different circadian and ultradian rhythms. 2. 2. Comparative studies show a strong respiratory and locomotor activity synchronization by interindividual contacts in mice, and by L-D in quails. 3. 3. In rats, interindividual synchronization is as important as L-D synchronization. 4. 4. An ultradian societal rhythmicity has been demonstrated in guinea-pigs.