Kappen KL, Garner LM, et al. Effects of photoperiod on food intake, activity and metabolic rate in adult neutered male cats. J Anim Physiol Anim Nutr (Berl). 2014 Oct; 98(5) 958–967.
The objective of this study was to determine the effects of increased photoperiod (longer days) on physical activity levels, metabolic rate, food intake, and fasting levels of hormonal compounds. During two 12-week periods, cats were exposed to either a short-day (SD) photoperiod of 8 h light: 16 h dark or a long-day (LD) photoperiod of 16 h light: 8 h dark. Cats were fed a commercial diet to maintain baseline body weight. In addition to daily food intake, twice-weekly measurements of body weight; metabolic rate, body composition and physical activity were measured twice daily. Fasting serum leptin and ghrelin concentrations were measured at week 0, 6 and 12 of each period.
Average hourly physical activity was greater in LD vs. SD cats which was primarily due to increased dark period activity. This corresponded to higher daily metabolizable energy intake, and increased metabolic rate in LD cats. Body composition, serum leptin and serum ghrelin were not altered by photoperiod. More research is needed to determine potential mechanisms by which these physiological changes occurred and how they may apply to weight management strategies. (MK)
Bermingham EN, Weidgraaf K, et al. Seasonal and age effects on energy requirements in domestic short-hair cats (Felis catus) in a temperate environment. J Anim Physiol Anim Nutr (Berl). 2013 Jun; 97(3):522–530.