Influence of storage length on the nutritive value of baleage

High-quality forages can benefit from being harvested as baleage when the environmental conditions are not favorable for dry hay production. Currently, it is recommended that baleage should be fed within 9-months post-harvest; however, mild winters can reduce the demand for these stored forages. Data are limited on the changes in nutritive value of baleage stored beyond the recommended timepoint. Therefore, the objective was to determine the effect of storage length on nutritive value of forage harvested and stored as baleage. This study evaluated baleage harvested from 2016 to 2018 in Tifton, GA, consisting of either bermudagrass (Cynodon dactylon L. Pers.), or a mixture of bermudagrass and alfalfa (Medicago sativa L.). Baleage was sampled for nutritive value analysis at 6-weeks and 9- and 12-months post-harvest, with a subset of bales sampled at 24 months. Regardless of forage, crude protein, total digestible nutrients, and in-vitro dry matter digestibility at 48 h were not impacted in bales sampled up to 12-months post-harvest (p > 0.07). However, acid detergent fiber increased when baleage was stored beyond 6 weeks but did not change from 9 to 12 months (p < 0.01). In the subset of bales stored up to 24-months post-harvest, all nutritive value parameters evaluated were negatively impacted (p < 0.01). The prolonged storage period may negatively affect the baleage plastic integrity, resulting in a decline in nutritive value if anaerobic conditions are not maintained. Future research is warranted to evaluate the changes in the fermentation profile of baleage under extended storage conditions.