Abstract
Barley grain containing more fermentable starch or fiber might be an attractive energy source in weaned pig diets due to benefits on gut health. Barley rapidly-fermentable carbohydrates may serve as prebiotic and slowly-fermentable fiber may decrease diarrhea in weaned pigs. Steam-explosion processing may disrupt the fiber matrix of hulls, increasing slowly-fermentable fiber of barley. To explore, 220 pigs were fed 1 of 5 diets containing 60% cereal grain: 1) low-fermentable hulled barley (LFB); 2) LFB steam-exploded (LFB-E; 1.2 MPa, 120 s); 3) high β-glucan (10% DM) hull-less barley (HFB); 4) high amylose (17% DM) hull-less barley (HFA); or 5) low-fermentable wheat (LFW). Diets were fed starting 1-week post-weaning and formulated to provide 2.4 and 2.3 Mcal net energy (NE)/kg, 5.5 and 5.1 g standardized ileal digestible lysine/Mcal NE for phase 1 (day 1–14) and phase 2 (day 15–35), respectively. For the entire trial (day 1–35), average daily feed intake (ADFI) and average daily gain (ADG) of pigs did not differ among diets. Gain:feed (G:F) did not differ between LFB and LFW diets, but steam-explosion of hulled barley reduced (P < 0.05) G:F. Feces consistency did not differ between LFB and LFW diets, but was better (P < 0.05) for LFB than HFB, HFA and LFB-E diets. For phase 1, G:F of pigs was lower (P < 0.05) for LFB-E diet than LFW diet. For days 22–28, LFB-E diet had greater (P < 0.01) ADFI than HFA diet and tended (P = 0.09) to have a greater ADG than HFB diet. In conclusion, hulled or hull-less barley grain replaced wheat grain without affecting growth performance in weaned pigs. Hulled barley increased feces consistency. Steam-explosion of hulled barley did not increase growth performance of weaned pigs. Barley grain is an attractive energy source for weaned pigs for managing growth and feces consistency.