Effects of Corn Particle Size and Diet Form on Finishing Pig Growth Performance and Carcass Characteristics20 March 2014
At the 2013 Kansas Swine Day, University researchers reported a study showing that finishing pigs performed better on the pelleted diet than meal, as expected, but there was no advantage in fine-grinding the corn in pelleted diets. Carcass parameters were not affected by dietary treatment.
A total of 960 pigs (PIC TR4 × Fast Genetics York-AND × PIC Line 02, initially 75.7 lb bodyweight) were used in a 101-day trial to determine the effect of corn particle size and diet form on finishing pig growth performance and carcass characteristics, J.E. Nemechek of Kansas State University told the Swine Day.
Pens were randomly allotted to one of six experimental treatments by initial bodyweight with eight pens per treatment and 20 pigs per pen. All diets were fed in four phases with the same corn-soybean meal–based diet containing 30 per cent dried distillers grains with solubles (DDGS; Phases 1 to 3) or 15 per cent DDGS (Phase 4) used for all diets.
The six experimental treatments were arranged in a 2×3 factorial with main effects of final feed form (meal versus pellet) and corn particle size (650μ, 350μ or an equal blend of the 650μ and 350μ ground corn).
Overall (days 0 to 101), linear particle size × diet form interactions were observed (P<0.02) for average daily feed intake and feed:gain ratio due to average daily feed intake decreasing and feed:gain ratio improving as particle size was reduced for pigs fed meal diets but not for pigs fed pelleted diets.
Pigs fed pelleted diets had increased (P<0.001) average daily gain and final bodyweight and improved (P<0.001) feed:gain ratio.
As corn particle size decreased, average daily gain and average daily feed intake decreased (P<0.02) linearly.
Pigs fed pelleted diets had increased (P<0.001) hot carcass weight than those fed meal diets.
Yield, backfat and loin depth were not influenced by particle size or diet form.
Nemechek and colleagues concluded that pigs fed pelleted diets had improved growth performance compared with those fed meal diets, with the greatest improvement in feed:gain ratio observed from pigs fed coarse-ground (650μ) corn.
Feed efficiency improved as corn particle size decreased for pigs fed meal diets but not for those fed pelleted diets, suggesting that there was no benefit to grinding corn finer than 650μ for pelleted diets.
Nemechek J.E., M.D. Tokach, K.F. Coble, J.M. DeRouchey, R.D. Goodband and S.S. Dritz. 2013. Effects of corn particle size and diet form on finishing pig growth performance and carcass characteristics. Proceedings of 2013 Kansas Swine Day, p110-115.