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Effects of fine grinding corn or dried distillers grains with solubles (DDGS) and diet form on growth performance and caloric efficiency of 11- 22-kg nursery pigs
Little is known about the effects of fine-grinding other ingredients in combination with grinding the corn or the effect that form (meal vs. pellet) of these diets may have on nursery pig performance. Thus, a total of 687 pigs (PIC 1050 barrows; initially 11.6 kg BW and 37 d of age) were used in a 21-d study to determine the effects of fine grinding corn and/or DDGS and diet form (meal vs pellet) on growth performance and caloric efficiency of nursery pigs. Pigs were allotted to 1 of 10 dietary treatments (14 pens/treatment and 5 pigs/pen) using 2 groups of nursery pigs. The 10 diets included 4 corn-soybean meal-based diets consisting of: (1) corn ground to ~638 µ in meal form; (2) treatment 1 in pellet form; (3) corn ground to ~325 µ, in meal form, and (4) treatment 3 in pellet form. The remaining 6 diets contained 30% DDGS. Diets 5 through 10 consisted of: (5) corn and DDGS ground to ~638 and 580 µ, in meal form; (6) diet 5 in pellet form; (7) corn and DDGS ground to ~638 and 391 µ, in meal form; (8) diet 7 in pellet form; (9) corn and DDGS ground to ~325 and 391 µ, in meal form, and (10) diet 9 in pellet form. Diets were formulated to 1.28% SID Lys and were not adjusted for energy as DDGS was added. Overall, a corn particle size × diet form interaction was observed (P<0.01) as a result of increased ADFI when corn was finely ground and fed in pellet form but decreased intake when corn was finely ground and fed in meal form. Pelleting diets decreased (P<0.001) ADG (594 vs 560 g), ADFI (872 vs 864 g), and final BW (23.8 vs 23.2 kg) but improved (P<0.001) G:F (0.63 vs 0.65) and caloric efficiency on both an ME and NE basis. Fine-grinding corn decreased (P<0.04) ADG (588 vs 572 g) as a result of numerically decreased ADFI (P>0.16). Feeding 30% DDGS also decreased (P<0.01) ADG (591 vs 568 g), ADFI (897 vs 898 g), and NE caloric efficiency and tended to decrease (P<0.07) final BW (23.7 vs 23.3 kg). In conclusion, pelleting nursery diets and fine-grinding ingredients reduced ADG as a result of decreased ADFI, which resulted in improved feed efficiency.
Keywords: DDGS, nursery pig, feed processing, pelleting