This study evaluated the nutritional and neutral detergent fiber digestibility (NDFD) characteristics of seven barley varieties (‘Conlon’, ‘CDC Copeland’, ‘CDC Cowboy’, ‘Falcon’, ‘Legacy’, ‘AC Metcalfe’, and ‘Xena’) grown for silage. Commercial samples (n = 80) harvested at the mid-dough stage were collected over 2 years (2012 and 2013). Average pH and dry matter (DM) content were 4.05% ± 0.17% and 36.8% ± 4.1%, respectively. ‘Falcon’ and ‘AC Metcalfe’ had higher (P < 0.05) CP relative to ‘CDC Copeland’ and ‘Xena’, with intermediate values for the other varieties. Acid (ADF) and neutral (NDF) detergent fiber contents were higher (P < 0.05) for ‘CDC Cowboy’ relative to ‘Conlon’. Starch was higher (P < 0.05) for ‘Legacy’ and ‘Conlon’ than ‘CDC Cowboy’, with intermediate values for other varieties. Legacy had a greater (P < 0.05) 6-h NDFD while ‘CDC Cowboy’ had a greater (P < 0.05) 30-h NDFD. Indigestible NDF (INDF; % NDF) was greater (P < 0.05) for ‘AC Metcalfe’ relative to ‘CDC Cowboy’ and ‘Falcon’. These results indicate that barley varieties vary with respect to chemical composition and NDFD and INDF contents. Selection for higher 30-h NDFD could result in improvements in DM and DE intake and performance of growing beef cattle.

This study evaluated the effects of inoculation of whole crop corn silage with a mixture of heterofermentative lactic acid bacteria (LAB) composed of Lactobacillus hilgardii and Lactobacillus buchneri on ensiling, aerobic stability, ruminal fermentation, total tract nutrient digestibility, and growth performance of beef cattle. Uninoculated control corn silage (CON) and silage inoculated with 3.0 × 105 cfu g-1 of LAB containing 1.5 × 105 cfu g-1 of L. hilgardii CNCM I-4785 and 1.5 × 105 cfu g­1 of L. buchneri NCIMB 40788 (INOC) were ensiled in silo bags. The pH did not differ (P &gt; 0.05) between the two silages during ensiling but was greater (P &lt; 0.001) for CON than INOC after 14 d of aerobic exposure (AE). Neutral detergent insoluble crude protein (NDICP) content (% of DM and % of CP basis) of terminal INOC silage was greater (P ≤ 0.05) than that of CON. In terminal silage, concentrations of total VFA and acetate were greater (P &lt; 0.001) while water-soluble carbohydrates were lower (P &lt; 0.001) for INOC than CON. Yeast and mold counts were lower for INOC than CON (P ≤ 0.001) in both terminal and aerobically exposed silages. The stability of INOC was greater (P &lt; 0.001) than that of CON after 14 d of AE. Ruminal fermentation parameters and DMI did not differ (P &gt; 0.05) between heifers fed the two silages, while there was a tendency (P ≤ 0.07) for lower CP and starch digestibility for heifers fed INOC than CON. Total nitrogen (N) intake and N retention were lower (P ≤ 0.04) for heifers fed INOC than CON. Dry matter intake as a % of BW was lower (P &lt; 0.04) and there was a tendency for improved G:F (P = 0.07) in steers fed INOC vs CON silage. The NEm and NEg contents were greater for INOC than CON diets. Results indicate that inoculation with a mixture of L. hilgardii and L. buchneri improved the aerobic stability of corn silage. Improvements in G:F of growing steers fed INOC silage even though total tract digestibility of CP and starch tended to be lower for heifers fed INOC is likely because the difference in BW and growth requirements of these animals impacted the growth performance and nutrient utilization, and a greater proportion of NDICP in INOC than CON.

This study evaluated the effects of a novel silage inoculant containing Saccharomyces cerevisiae strain 3 as a direct fed microbial (DFM) on the ensiling, aerobic stability, and nutrient digestibility of whole-crop corn silage and growth performance of beef cattle. Treatments included uninoculated corn silage (CON) or corn silage inoculated with a mixture of 1.1 × 105 cfu g−1 fresh forage Lactobacillus plantarum and Lactobacillus buchneri (INOC1) or 1.0 × 104 cfu g−1 fresh forage S. cerevisiae strain 3 (INOC2) or a mixture of INOC1 and INOC2 (INOC3). Silage in INOC1 had lower (P = 0.03) proportion of lactate, with acetate (Ac) proportion ranking as INOC1 &gt; INOC3 &gt; INOC2 (P &lt; 0.01). In terminal silage, numbers of lactic acid bacteria were greater (P = 0.05) for INOC1 than CON and INOC2, while yeast counts tended (P = 0.08) to be greater for INOC2 than INOC3 on day 3 of aerobic exposure. Aerobic stability of corn silage was not impacted by inoculation with S. cerevisiae strain 3. Heifers fed INOC2 and INOC3 had lower (P &lt; 0.01) ruminal Ac concentration than those fed CON. Apparent total tract digestibilities of DM, OM, ADF, and NDF were greater (P ≤ 0.03) for heifers fed INOC2 than those fed CON. Growth performance was similar across treatments, excepting DMI as percent of BW tended to be lower (P = 0.08) for INOC2 steers compared to CON steers. These results suggest that S. cerevisiae strain 3 has potential as a component in a fourth generation DFM silage inoculant.

This study evaluated the effect of variety (V; CDC Cowboy, CDC Copeland, and Xena) and stage of harvest maturity (M; milk, early-, mid-, and hard-dough) on nutrient and neutral detergent fiber digestibility (NDFD) characteristics of barley forage using a randomized complete block design with 3 × 4 factorial treatment arrangement. Barley varieties had similar crude protein, but CDC Cowboy had greater (P < 0.01) acid detergent fiber (ADF), neutral detergent fiber (NDF), and lignin, and lower (P < 0.01) total digestible nutrient (TDN) content relative to Xena. Starch content of CDC Cowboy was lower (P < 0.01) than Xena at all stages of maturity with CDC Copeland intermediate at early- and mid-dough stages. Crude protein, ADF, NDF, and lignin content decreased (P < 0.01) while starch and TDN content increased (P < 0.01) with advancing maturity. Xena had greater (P < 0.01) NDFD, as determined by 6 h in vitro incubation using DaisyII system (NDFD6h), at milk, mid- and hard-dough stages of maturity than CDC Cowboy with CDC Copeland intermediate at mid-dough. However, CDC Cowboy had greater (P < 0.01) NDFD, as determined by 30 h in vitro incubation using DaisyII system (NDFD30h), at early-dough stage than Xena and greater NDFD30h at hard-dough stage than CDC Copeland. Xena had the lowest (P < 0.01) indigestible NDF based on 288 h ruminal in situ incubation (INDF288h), relative to CDC Copeland. These results indicate that to optimize NDFD30h, variety should be considered when deciding the timing of harvest.

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