Objective: To investigate the 12h: 12h light/dark changes
of feeding , drinking and defecation in laboratory rabbits. Design: Experimental study.
Animals: Ten male New Zealand white rabbits weighing
2.5-3kg.
Procedure: Rabbits were individually maintained in
standard cages (45 45 60cm) in a laboratory under
controlled temperature (20 - 23°C) and 12/12h light - dark
cycles for induction of adaptation. They were fed with a
commercial pelleted diet and water twice daily (7.00 and
19.00h). Fecal pellets and consumed food and water were
measured every 4h for 10 consecutive days . The rates and
ratio; of the above mentioned parameters were calculated
at 12h light, 12h dark and total 24h periods.
Statistical analysis: Repeated measures ANOVA and
Duncan test.
Results: Maximal rates of food and water intake were
obtained at 19-23 and 23-3h time intervals. Their minimal
rates were occurred at 3-7h time interval. Defecation, with
minimal rates at 7-11 and 11-15h time intervals, showed
maximal rates at 15-19, 19-23 and 23-3h time intervals.
Food, water intake and defecation rates at 12h dark period
were higher than that of 12h light period. The 12h dark/
total 24h ratios of the parameters were higher than that of
12h light/total 24h ratios, too.
Clinical implication: From the results of this study it is concluded that laboratory rabbits perform more of feeding,
drinking and defecation activities from the beginning to
middle hours of dark period. From this point of view,
rabbits belong to the nocturnal animals group.
J.Fac. Vet.Med. Univ. Tehran. 60,2:173-176,2005.