PSIV-B-28 Effect of feeding acidified or fermented barley grain using Limosilactobacillus reuteri with or without supplemental phytase on diet nutrient digestibility in growing pigs

Abstract

Abstract Fermentation of cereal grains may degrade myo-inositol hexakisphosphate (InsP6) thereby increasing nutrient digestibility. Effects of chemical acidification or fermentation with Limosilactobacillus (Lm.) reuteri TMW 1.656 with or without phytase on nutrient digestibility of diets composed of high β-glucan hull-less barley grain were assessed in growing pigs. Four mash diets contained 50% barley grain: 1) unfermented barley (Control); 2) chemically-acidified barley (ACD) with lactic and acidic acid [0.02 L/kg barley grain, 4:1 (v/v)]; 3) barley fermented with Lm. reuteri (Fermented without phytase); and 4) barley fermented with Lm. reuteri and phytase (Fermented with phytase; 500 FYT/kg barley grain). The 4 diets were fed to 8 ileal-cannulated barrows (initial BW, 17.4 kg) for four 11-d periods in a double 4 × 4 Latin square. The InsP6 content of barley grain in Control, ACD, Fermented without phytase, or Fermented with phytase was 1.12, 0.59, 0.52% dry matter, or not detectable, respectively. Diet apparent total tract digestibility (ATTD) of crude protein (CP), Ca, gross energy and digestible energy and predicted net energy values were greater (P < 0.05) for ACD and Fermented without phytase than Control. Diet apparent ileal digestibility (AID) of Ca and standardized total tract digestibility (STTD) of P tended to be greater (P < 0.10) for Fermented without phytase than Control. Diet STTD of P, AID and ATTD of Ca was greater (P < 0.05) for Fermented with phytase than Fermented without phytase. Acidification or fermentation with/without phytase did not affect diet standardized ileal digestibility of CP and AA. In conclusion, fermentation with phytase completely degraded InsP6 in barley grain and maximized P and Ca digestibility, thereby reducing the need to provide inorganic P to meet P requirements of growing pigs.