In nursery pigs, there were no observed differences in gain, feed consumption, feed efficiency, or economics for the roller mill configurations. However, there was a clear impact of roller mill configuration on feed preference, due to the particle size of the respective diets. In finishing pigs, ADFI and ADG were reduced when the particle size was reduced from 685 µ to 360 µ, with no observed improvement in feed efficiency. Although roller mill configuration had a substantial impact on the electricity cost and throughput, results did not indicate any benefit in feed efficiency or economic return when particle size was reduced below 685 µ by grinding through a roller mill when fed to finishing pigs.
Producer bottom line;
• Earlier research has shown a decrease in gain and feed intake when corn particle size is reduced below approximately 600 µ and fed in meal diets; however, the appreciable benefit in feed efficiency normally found with particle size reduction was not observed in these studies.
• Lowering particle size by increasing the number of grinding rolls increased electricity cost and decreased throughput.
• No benefit in performance or economics was observed when corn particle size was reduced below 650 µ and fed in meal diets to nursery or finishing pigs.
• Field experience indicates that a 3-high roller mill allows producers to more easily reach their particle size targets; however, these trials indicate no advantage to use of a 4-high roller mill.