A total of 208 pigs (104 barrows and 104 gilts, initial average 62.6 kg) were used in a 63-d experiment to determine the effects of adding cracked corn to diets for finishing pigs. The pigs were sorted by ancestry and blocked by weight with 13 pigs per pen and 4 pens per treatment. Treatments were corn-soybean meal-based with none, 10, 20, or 40% roller-milled corn (mean particle size of 3,549 μm). Particle size for the none, 10, 20, and 40% cracked corn diets were 684, 926, 979, and 1,187 μm, respectively. Feed and water were offered ad libitum until slaughter (average final BW of 121.6 kg) at a commercial facility.
Overall (d 0 to 63), increasing cracked corn from none to 40% had no effect on ADG (P > 0.98) and ADFI (P > 0.41), but F/G was numerically poorer (linear, P < 0.11). Adding cracked corn had no effect on hot carcass weight (P > 0.17) or backfat thickness (P > 0.69), but dressing percentage was decreased (linear effect, P < 0.05). For both stomach keratinization and ulcer scores, as the percentage of cracked corn increased, there was a decrease (linear, P < 0.009) in scores for ulcers and stomach keratinization (scale of 0 = none, 1 = mild, 2 = moderate, and 3 = severe), but even the worst treatment had an average lesion score of less than mild. It is concluded that increasing cracked corn from none to 40% of diets for finishing pigs did not affect rate of gain but worsened F/G and dressing percentage with only slight improvements in scores for stomach lesions.
SM Williams, CB Paulk, JD Hancock, S Issa, and TL Gugle, 2010. Swine day, Kansas State University, Report progress 1038: 115-118.