The rate of feedout through the silage mass must be sufficient to prevent the exposed silage from heating and spoiling. An average removal rate 6 to 12 inches from the face per day is a common recommendation. However, during periods of warm, humid weather, a removal rate of 18 inches or more might be required to prevent aerobic spoilage, particularly for corn, sorghum, and whole-plant wheat silages. Implications of Feeding Spoiled Silage . Sealing with a polyethylene sheet weighted with tires is not 100 percent effective.
Aerobic spoilage occurs to some degree in virtually all sealed silos.
And the discarding of surface spoiled is not always a common practice on the farm. The original top 3 feet of corn silage in a bunker silo was allowed to spoil, and it was fed to steers fitted with ruminal cannulas. The original top 18-inch layer was visually quite typical of an unsealed layer of silage that had undergone several months of exposure to air and rainfall. It had a foul odor, was black in color, and had a slimy, mud-like texture. The addition of surface-spoiled silage had large negative associative effects on DM intake and OM, NDF, and ADF digestibilities.