Aerobic Stability of Wheat and Orchardgrass Round-Bale Silage

摘要

In Arkansas, silage often is stored in long rows of round bales wrapped in plastic film that is described commonly as balage. It is important to evaluate the aerobic stability of this fermented forage when it is exposed to air, especially during the winter months when the majority of this product is fed to livestock, or sold as a cash crop. Two types of forage, orchardgrass (Dactylis glomerata L.) and wheat (Triticum aestivum L.), were harvested in May 2002 and stored as balage. Twenty-one bales of each forage type were unwrapped and exposed to air on December 10, 2002 for 0, 2, 4, 8, 16, 24, or 32 d to evaluate the aerobic stability of these silages. For both orchardgrass and wheat balage, final bale wt, dry matter (DM) content, and pH were not affected (P > 0.05) by exposure time. Across both balage types, DM recoveries were > 97% for all bales, indicating that both types of balage were very stable when exposed to air. Concentrations of neutral detergent fiber (NDF) and 48-h ruminal in situ digestibility were not affected (P > 0.05) by exposure time for either balage type. Concentrations of N were greater (P = 0.045) for orchardgrass balage exposed to air for 16 d or longer compared to balage sampled at exposure (d 0), but this response was notobserved (P > 0.05) for wheat balage. These results suggest that the balage evaluated in this trial was very stable after exposure to air for up to 32 d. This should allow considerable flexibility with respect to feeding, transport, and marketing of balage during winter months without significant aerobic deterioration.