Housing conditions and carbohydrate source affect within-day variation of energy metabolism in growing pigs

In the present study, effects of housing conditions (i.e. individual vs. group housing) and carbohydrate source (i.e. sugar beet pulp vs. maize starch) on energy metabolism and circadian rhythms in energy expenditure and physical activity were studied in growing pigs in a 2 x2 factorial design. No interactions between housing conditions and diet composition were present. Digestibility and metabolisability of dietary energy was higher for individually housed pigs than for group-housed pigs. Circadian rhythms in energy expenditure and energy expenditure for physical activity were clearly affected by housing conditions and diet composition. Total energy expenditure, as well as activity related energy expenditure, was increased during the dark phase of the day in individually housed pigs when compared with group-housed pigs. Pigs fed the sugar beet pulp based diet had a reduced energy expenditure on physical activity, which mainly occurred during the night