Daily rhythms in food intake and locomotor activity in a colony of domestic cats

BACKGROUND: Daily rhythms have been widely investigated in various mammals but, surprisingly, literature is scarce and conflicting regarding the domestic cat, Felis catus. This may come from the difficulty to analyse rhythms in a species showing high interindividual variability and from the common idea that the rhythms of the cat are rather random. To elucidate the subject, two groups of indoor cats (14 in total) living in a cattery room, were followed on a 24 h/7 day basis, using advanced telemetry technologies, i.e. passive RFID, automated weighing of electronic scales and UWB technology with accuracy ensuring a good reliability of the results. RESULTS: While covering on average 1.74 ± 0.4 km and eating 46.4 ± 3.6 g (≈ 179 kcal) of dry food per day, findings indicate 24 h periodicity in the locomotor and feeding rhythms of the cats. Systematically, their locomotor behaviour was more rhythmic than their eating behaviour (p < 0.01), possibly reflecting the flexibility of the eating patterns of the cat initially enabling it to adapt to daily rhythms of its prey. In their daily patterns, the indoor individuals showed two main troughs of activity and food intake—in the middle of the day and in the middle of the night—and two main peaks: one in the morning (especially before sunrise and food renewal), the other in the evening (following the end of the work day of the animal staff and before sunset), supporting previous work demonstrating peaks at dusk and dawn and confirming the crepuscular nature of the species. No general pattern emerged according to a more nocturnal versus diurnal organisation. CONCLUSIONS: Bimodality, more than chronotypes, seems therefore to best characterise the activity and feeding rhythms of the species as it was demonstrated in the individuals among the different categorisations. By validating the use of new tracking technologies as well as of adapted chronobiological parameters to assess the daily rhythm of cats living indoors, this study opens the way for more adequate analyses of cat behaviour through time under various conditions.