Two strategies for meeting energy demands of growing pigs at pasture. Livestock production science. 80, 167-174

The objectives were to compare extra feeding of energy to growing pigs on pasture by increasing the energy concentration (CONC) or the volume (VOL) of a standard diet. Fifty-four pigs, on two treatments were raised on pasture (CONC-OUT and VOL-OUT). Nine-teen pigs were raised indoors (CONC-IN). The DM consumption of the diet was not different between the CONC groups. The VOL-OUT groups increased their consumption but not enough to receive their planned ration. Consequencely, the VOL-OUT groups ate 10% less energy and and an equal amount of CP (instead of 15% more) as the CONC groups. DM and CP consumption from pasture was 4 to 8% of the total. There were indications that the CONC-OUT pigs supplemented their protein intake by selecting protein-rich pasture plants. There was a slight difference in DWG between CONC-OUT and VOL-OUT (870 vs. 904 g), and a significant difference in the dressing percentage (77.9 vs. 75.9), but no difference in carcass weight or lean meat percentage (56.0 vs. 56.6). The CONC-OUT had a lower growth rate (870 vs. 928 g), but were leaner (56 vs. 53.8 %) than the CONC-IN. From a production perspective, it is possible to increase the energy concentration of the diet for growing pigs on pasture. They can consume extra energy without putting on excess fat, and take aproximatly 5 % of their DM intake from pasture