A group of slow-growing Landrace and a group of fast-growing Large White boars were used to study their patterns of feed intake, growth rate and feed utilization. The pigs were fed ad libitum on a high-energy diet of a high protein content and quality. The data show no difference in mean daily feed intakes between the two groups. Mean daily live mass gain was, however, 174 g/day (20,5%) more for the Large White boars and feed conversion 16,5% better (both statistically significant at P ≤ 0,01). The fast-growing pigs also had only 15,7 mm of P2 backfat, 40% less than the 26,1 mm of the Landrace pigs at 86 kg live mass. Distinct intake and growth patterns were also established not only between the two pig groups, but also between individual pigs. Hence it is concluded that the absolute amount and pattern of feed intake is dictated by the animal's growth rate, its pattern of body protein and fat accretion, and the amount of food used for maintenance.
