We evaluated feeding reduced net energy (NE) levels to growing–finishing pigs. In a 2 × 4 factorial, 1008 pigs (29 kg) housed in 48 pens of 21 barrows or gilts were fed 2.4, 2.3, 2.2, or 2.1 Mcal NE kg-1 diets over five growth phases resulting in six pens per NE level × gender. For the entire trial, reducing NE by 0.1 Mcal kg-1 linearly increased (P < 0.001) average daily feed intake by 43 g and linearly decreased (P < 0.001) caloric intake by 0.12 Mcal d-1 and feed efficiency (G:F) by 0.007 Mcal kg-1; average daily weight gain was not affected. The proportion of pigs remaining in pens after the start of shipping for slaughter (day 78) was greatest (P < 0.05) for pigs fed 2.1 Mcal NE kg-1, but days to target slaughter weight (124 kg) did not differ. Carcass backfat, loin depth, lean yield, index, and carcass lean gain were not affected by NE. Reduced NE diets (≤2.3 Mcal NE kg-1) can therefore be fed to growing–finishing pigs instead of traditional energy levels (≥2.4 Mcal NE kg-1) as long as pigs can increase feed intake to compensate for reduced NE density.
caractéristiques de carcasse
performance de croissance