Six light crossbred (Duroc×Landrace×Yorkshire) growing pigs (initial BW: 32.5±2.1 kg) and six heavy crossbred (Duroc×Landrace×Yorkshire) growing pigs (initial BW: 59.4±3.2 kg) were surgically prepared with a T-cannula in the distal ileum according to the producer of Ren et al. (2011). All pigs were housed in stainless steel metabolism cages (1.4×0.45×0.6 m3).