Comparison of large round bale storage and feeding systems on dairy farms

The dairy forage system model (DAFOSYM) was expanded to predict dry matter and nutrient losses during the storage and feeding of large round alfalfa hay bales. Through simulation, the long-term performance, costs, and return above feed costs for six storage methods, three bale sizes, two feeding methods, and two milk production levels were compared on 60 and 400 cow representative dairy farms. The analysis included all factors of harvest, storage, feeding, and animal production including crop growth, machinery use, and hay dry matter, and nutrient losses. The value of bale protection was influenced by bale size, amount of hay in the diet, level of milk production, and feeding method. Shed storage was usually, but not always, more profitable than unprotected storage. The greatest economic return from bale protection occurred when small diameter bales were fed to high producing cows with all alfalfa fed as dry hay. Compared to unprotected hay, annual net return increased as much as $155/cow with shed storage and $143/cow with tarp-covered stacks. The least benefit from bale protection was when large diameter bales were chopped and fed as a small amount of a total mixed ration. With this system, annual net return was within $8/cow for all storage systems indicating little benefit for protected storage.