Photic and non-photic effects on the daily activity pattern of Mongolian gerbils.

The paper analyses the daily activity pattern of Mongolian gerbils with and without access to a running wheel. To evaluate the synchronizing and the masking effects of light, experiments were performed under different photoperiods (L:D=14:10 h and 10:14 h), and light and dark pulses were applied at different phases of the day-night cycle. In order to get a more direct estimate of the central pacemaker of the circadian system, the body temperature rhythm was investigated via implanted transmitters.

Influence of oxygen concentration on redox cycling of alloxan and dialuric acid.

Alloxan, a chemical diabetogen, decays in the absence of reductants into alloxanic acid. In the presence of glutathione, it is reduced via the alloxan radical into dialuric acid, which autoxidizes back to alloxan. During this redox cycling process, reactive oxygen species are formed that destroy beta-cells in islets of Langerhans.

Male expulsion in cooperative Mongolian gerbils (Meriones unguiculatus).

Mongolian gerbils are territorial rodents of steppes and semideserts of Mongolia and Northern China. At least under laboratory conditions, the family life is characterized by long-term harmonious and short-term aggressive periods in which some members are expelled. The purpose of this study was to clarify which features of male offspring promote their expulsion.

Indicators for post-surgery recovery in Mongolian gerbils (Meriones unguiculatus).

Telemetric investigations of various parameters are widely used to estimate an animal's state. However, the implantation of the transmitters includes anaesthesia and surgery and has short and longer lasting impacts on the studied object. The aim of the present paper was to evaluate these effects in Mongolian gerbils, namely the hypothermia caused by the anaesthetic and the enduring disturbance of daily rhythmicity until complete recovery.

Running-wheel activity and body composition in golden hamsters (Mesocricetus auratus).

Running wheels are frequently used in behavioural and physiological experiments. The function of wheel-running activity in laboratory animals is controversial. In the present long-term study, the influence of this activity was evaluated in male golden hamsters over a period of 52 weeks.