Ensiling barley cultivars selected for varied levels of in vitro neutral detergent fiber digestibility in mini and bunker silos to evaluate effects on fermentation

Abstract

Thirty hour in vitro neutral detergent fiber digestibility (NDFD) of three barley cultivars such as ‘CDC Cowboy’ [high-neutral detergent fiber digestibility (H-NDFD)], ‘CDC Copeland’ [intermediate-neutral detergent fiber digestibility (I-NDFD)], and ‘Xena’ [low-neutral detergent fiber digestibility (L-NDFD)] was ranked from 80 commercial silage samples. Cultivars were seeded on the same day, harvested at mid-dough, and ensiled in mini or bunker silos. Mini silos were sequentially opened over 60 d, and day 60 samples were exposed to air for 21 d. Bunker silos were sampled after 60 d. Cultivars did not differ in NDFD, while terminal pH was lower (P < 0.01) for H-NDFD than other silages. The pH of H-NDFD was greater (P < 0.01) and pH of Iand L-NDFD lower (P < 0.01) in bunker than mini silos. Lactate and acetate were greater (P < 0.05) for H-NDFD in mini silos, with lower (P < 0.01) acetate in mini than bunker silos. Intermediate NDFD mini silos were greater (P < 0.01) in acid detergent fiber (ADF) and NDF compared with other silages, traits which were also greater (P < 0.01) for H-NDFD and L-NDFD in bunker vs. mini silos. High-NDFD silage was less aerobically stable than other silages. Using NDFD of field silage samples to select barley silage cultivars for improved NDFD is not a viable strategy based on the results of this study.