Effect of alfalfa cultivar and bale wrap type on dry matter and forage quality of large round bales in outdoor storage

Large round bales are commonly fed to livestock; however, it has been well documented that outdoor storage can negatively impact dry matter (DM) and forage quality. To reduce storage losses and improve feeding value, new wrap types and alfalfa cultivars have been developed; however, these options have not been extensively investigated. Therefore, the objectives of this research were to evaluate the time required to bind large round bales, determine changes in DM and forage quality, and examine the economics of reduced-lignin and conventional alfalfa hay bound in twine, net wrap, and B-Wrap^® while in outdoor storage. Hay was baled into 24 large round bales; 12 bales each of reduced-lignin and conventional alfalfa. Within each cultivar, four replicates were bound with each wrap type. Using stopwatches, the time to bind each bale was recorded. At the time of harvest, and every 90±3 days for 365 days, individual bales were weighed and cored to determine changes in DM and forage quality. Significance was set at P ≤ 0.05. Time to bind a bale was longest for twine, intermediate for B-Wrap^®, and shortest for net wrap (P < 0.01). Alfalfa cultivar had minimal effects on the parameters measured; therefore, the interaction between wrap type and storage length was reported. After 365 days in outdoor storage, DM losses were 7% for twine bales, 5% for net wrap bales, while B-Wrap^® bales maintained DM. Changes in forage quality were observed at ≥180 days of storage where nonstructural carbohydrates were decreased and insoluble fiber components were concentrated. B-Wrap^® bales had a higher value compared to net wrap and twines bales at 180 and 270 days in storage. These results suggest that B-Wrap^® was better able to shed precipitation which preserved forage quality and bale value compared to large round bales bound in net wrap and twine in long term, outdoor storage.