Abstract
Wilted hay-crop silages are difficult to manage for ensiling at an optimum dry matter. Even at optimum dry matter, protein degradation is considerable. If the forage becomes too dry, additional pro- tein becomes indigestible from heat dam- age. Untreated direct-cut silages have low recoveries of energy and nitrogen. Protein degradation is extensive during storage. Low intake, partial feed conversion, daily animal production, and animal produc- tion per ton or hectare result. Formic acid may be used to desiccate standing forage in an effort to control dry matter, but adding formic acid to direct-cut forage at the silo is probably as beneficial. Formic acid alone, formic acid-formalde- hyde, or formaldehyde alone eliminate many of the problems of direct-cut silage. Amounts of formaldehyde, when used alone, may be too critical for farm use. Formic acid also improves the quality and animal responses with wilted silages. Pro- pionic acid controls the heat damage in wilted silages where the forage becomes too dry before ensiling. Sodium, calcium, and ammonium hydroxides increase the digestibility and intake of crop residues enough to m~tke them more valuable feedstuffs for ruminants.