Influence of Degree of Fermentation on the Utilization of Energy from Alfalfa-Brome Forage

Studies were conducted with alfalfa-brome forage (alfalfa-brome, aerial part, early bloom, cut 2) harvested as hay (86.6% dry matter), haylage (50.8% dry matter) and silage (41.8% dry matter) to determine harvest and storage losses, performance of calves fed these feeds as their only energy source, net energy values and the efficiency of energy utilization for the three forage systems. Dry matter losses during harvesting were 25.4, 14.6 and 12.4% for hay, haylage and silage. Dry matter losses totaled 29.4, 22.1 and 21.3% and crude protein losses totaled 25.8, 27.6 and 21.2% during harvesting and storage for the respective feeds. Steer calves fed alfalfa-brome hay or haylage as their only source of dietary energy gained faster and consumed more dry matter than steers fed silage. Amounts of dry matter per 100 kg of gain were 1,099, 1,216 and 1,261 kg for steers fed hay, haylage and silage, respectively. Gain per hectare was not greatly influenced by method of harvesting and storage.