INVESTIGADORES
VALENTINUZZI veronica Sandra
congresos y reuniones científicas
Título:
Time restricted feeding and food-antecipatory activity in an herbivorous subterranean rodent, the tuco-tuco (Ctenomys aff. knight).
Autor/es:
FLORES DANILO EFL; DOKKEDAL D; ODA GA; VALENTINUZZI VS
Lugar:
Montana
Reunión:
Congreso; Society for Research in Biological Rhythms Meeting- SRBR; 2014
Institución organizadora:
Society for Research in Biological Rhythms- SRBR
Resumen:
Tuco-tucos (Ctenomys spp.) are subterranean rodents that feed mostly on aerial parts of plants. Different from rats, which are opportunistic and omnivorous, tuco-tucos experience stable food availability in their natural environment on a 24-hour scale. We investigated whether Ctenomys aff. knighti would present food anticipatory activity (FAA), despite the little selective pressure for daily food anticipation. In previous experiments, tuco-tucos did not adjust properly to time restricted feeding when food was available for 3 hours per day. They ingested less food than in ad libitum feeding conditions and presented body weight loss. However, another previous experiment with 9 hours of feeding per day could be sustained for 74-84 days, without considerable weight loss from animals. Part of the individuals presented FAA. In the present experiment we now attempted to adjust animals to shorter feeding time windows (< 9 hours) by gradually decreasing the duration of daily food availability. For this study, 7 animals were maintained in running-wheel cages, under an LD12:12 regimen, and were firstly subjected to 6 days of ad libitum food. We then started the timerestricted feeding protocol: 9 hours of food per day (10:00 ? 19:00) for 31 days, 6 hours of food per day (10:00 ? 16:00) for 13 days and 5 hours of food per day (10:00 ? 15:00) for 5 days. Diet consisted of carrots and sweet potatoes. We monitored wheel-running activity rhythms, daily food ingestion and body weight every 3-4 days. Six of the animals had implanted telemetric transmitters (G2 E-Mitters,Mini-Mitter, Bend, OR), for the recording of general activity. Two animals presented robust FAA and one expressed temporary FAA in running-wheel activity, during the days of 9-hour feeding window. Upon reduction in food availability time, some animals lost weight and had to be removed from experiment. One animal that did not present FAA in a 9-hour feeding window started to express low amplitude FAA under the 6-hour/5-hour feeding windows. Another individual expressed temporary FAA in general activity, but not in wheel running, upon the change from 9-hour to 6-hour daily feeding. Although weight was maintained in these two cases, the experiment was interrupted due to the emergence of hyperactive behavior. In summary, tuco-tucos present great variability in FAA expression and general adjustment to daily feeding windows of 6 hours or less. Results may be related to physiological limitations inherent to the natural feeding habits of the species