The effects of cold pelleting and separation of fine corn particles on growth performance of nursery pigs

A total of 320 pigs (DNA 241x600; initially 10.2 kg BW) were utilized in a 21-d experiment to determine the effects of corn fractionation and pelleting technique on nursery pig growth performance. There were 5 pigs per pen, 8 pens per treatment and 8 dietary treatments in a randomized complete block design. Treatments 1-3 contained 400 pm ground corn and were fed as either mash, pelleted using a steam conditioner plus traditional vertical ring die (steam pellet) or pelleted with hot water plus a horizontal die (cold pellet). Treatments 4-6 contained corn ground to 400 pm with fines < 150 um removed and were fed as either mash, steam pellet or cold pellet. Treatments 7 and 8 contained ground corn with only fines < 150 um steam or cold pelleted prior to dietary inclusion without complete diet pelleting. Overall, pigs fed mash diets had improved (P < 0.05) ADG and d 21 BW compared to those fed steam pelleted diets with those fed cold pelleted diets being intermediate. There was no difference in G:F between pigs fed mash, steam pellet and cold pellet diets; however, pigs fed diets containing pelleted fines had decreased (P < 0.05) G:F due to an observed increased feed wastage and sorting. There was no difference in growth performance between pigs fed diets with fines removed or not. Cold pelleting was a viable option to steam pelleting in the current experiment; however, pelleting diets reduced pig performance compared to pigs fed mash diets, which was unexpected. Further research is needed to validate the response to cold pelleting when the expected response to pelleting using steam conditioning is achieved.