Alfalfa: Hay, Haylage, Baleage, and Other Novel Products

Alfalfa hay utilization by dairy cattle has expanded in western dairy states. Alfalfa silage utilization has increased in the Midwest. Alfalfa haylage contains high levels of nonprotein nitrogen (NPN) due to protein breakdown during fermentation. Excessive levels of NPN in alfalfa silage diets require supplementation of protected protein sources to meet protein demands of high-producing cattle. Alfalfa hay contains less NPN than alfalfa silage, 10 vs 52% of total nitrogen for hay and silage, respectively. Addition of high-quality alfalfa hay or haylage into dairy cow diets that is low in NDF increases dry matter intake and buffers rumen pH provided fiber length is effective. Alfalfa forage needs to be modified to protect protein in the silo and the rumen and to increase fiber digestion to maintain high levels of alfalfa in dairy cow diets. New uses of alfalfa to remove nitrates from contaminated soils and new processing of valued-added alfalfa products increase the potential of alfalfa being included in crop rotations of cash crops. Processing alfalfa to obtain new value-added products includes three different fractionation methods: 1) wet fractionation (separation into a juice fraction and a fiber fraction); 2) dry fractionation (separation into leaves and stems); and 3) fractionation by passage of the whole herbage through the digestive systems of ruminant animals, leaving a high fiber residue. Phytase from transgenic alfalfa has been tested in poultry and swine rations. Chicks supplemented with phytase from transgenic alfalfa juice or leaf meal had growth equal to chicks fed phosphorus-supplemented rations; manure from the chicks supplemented with alfalfa phytase contained less than half the phosphorus levels of manure from chicks fed inorganic phosphorus supplements. Alfalfa hay can be fractionated to yield stems and leaf meal. Alfalfa leaf meal has been shown to be an acceptable supplement to replace a portion of alfalfa hay and soybean meal in diets of lactating dairy cattle; it can also replace protein supplements in beef cow diets, finishing steer diets and diets of growing turkeys. The fiber portion of alfalfa can produce lactic acid and ethanol. The fiber from alfalfa manure has yielded pressboard and water filters capable of removing heavy metals from contaminated water.