Intake and digestibility of big bluestem hay and baleage

• Published in: Crop science Vol. 52; no. 5; pp. 2413 - 2420
• Main Authors: Burns, J.C, Fisher, D.S
• Format: Journal Article
• Language: English
• Published: Madison, WI Crop Science Society of America 01.09.2012; The Crop Science Society of America, Inc; American Society of Agronomy
• Subjects: Agronomy. Soil science and plant productions; Andropogon gerardii; beef; Biological and medical sciences; Body weight; diet; digestibility; Drought; Dry matter; Experiments; Fundamental and applied biological sciences. Psychology; Grasses; harvest date; Hay; heading; humid zones; mastication; Pastures; Rain; rumination; Soil sciences; steers; Hay; Monocotyledones; Andropogon gerardii; Gramineae; Angiospermae; Spermatophyta; Fodder crop; Baling; Digestibility
• ISSN: 1435-0653; 0011-183X; 1435-0653
• DOI: 10.2135/cropsci2012.02.0123

Big bluestem (Andropogon gerardi Vitman) has potential to be a source of preserved forage for the mid-Atlantic Region. This 3-yr study compares its preservation as hay, direct-cut (DC) baleage, and wilted (WT) baleage when harvested in the late-boot to heading stage. The DC baleage averaged 373 g kg(-1) dry matter (DM) and WT averaged 536 g kg(-1) DM. The DC baleage had a pH of 5.2 vs. 5.6 (P = 0.06) for the WT. Steer (Bos taurus) intakes of the DC and WT baleage were similar (1.72 kg per 100 kg body weight) and greater (P = 0.07) than intake of hay (1.52 kg per 100 kg body weight). Apparent total tract DM digestibility was greater (P = 0.03) for hay (545 g kg(-1)) than the similar (504 g kg(-1)) baleage treatments. Steers selected a diet with greater in vitro true DM disappearance (71 g kg(-1)) and not altered by preservation method. Rumination chews per day and chews per minute and total number of boluses per day were greater (P <= 0.10) for DC baleage, reflecting its greater (P = 0.07) DM intake. Big bluestem dried rapidly providing an advantage for conservation in humid regions. Forage cut by 0900 h reached 800 g kg(-1) DM by 1700 h when tedded and by 1100 h the second day in narrow swath. Forage cut at 1700 h reached 800 g kg-1 DM by 1500 h the next day when tedded but not until 1100 h the third day in narrow swath. Big bluestem harvested at early heading is of moderate quality when preserved as hay or DC baleage and dries rapidly giving it a role in beef production systems in the humid mid-Atlantic Region.