Effects of grinding, pelleting and expanding on nutritive value of barley in pig diets

Abstract

Nutrient digestibility and protein utilization responses ofgrowing pigs to different processes of barley were evaluated. The assayed treatments of barley were grinding methods: hammer milling (FIM) and rolling (RM), pelleting (FIP, RP), expanding (HE, RE) and their combination (HEP, REP). The study comprised a 8 x 8 Latin square designed digestibility and nitrogen balance trial with a 2 x 2 x 2 factorial arrangement of treatments. The average grist size of HM barley was smaller and wider than that of RM. Pelleting and expanding reduced the grist size and made the distribution wider compared to untreated ones. HM compared to RM achieved improved pellet quality, but expanding had no effect on pellet durability. Only small differences were found in the proximate composition or sugar content indicating a gelatinization degree of differently processed barleys. Grinding method had no effect on organic matter (OM) digestibility, whereas RM improved protein (CP) digestibility (P