Effect of formic acid, formic acid salt and formic acid with formalin on silage fermentation, digestibility and intake, and on liveweight change of young cattle

Data from four experiments conducted at ADAS Liscombe Research Centre during 1977-1982 were used to compare unwilted silage treated with either formic acid (FA), a complex formic salt (FS) and formic acid with formalin (FF) with non-additive-treated silage (C), made from herbage with dry matter (DM) 166 g/kg and water-soluble carbohydrate (WSC) 21 g/kg. Following ensilage, the DM content of C was significantly less than that of the other treated silages. Compared with C, the additive treatments significantly decreased pH, acetic acid, butyric acid, total short-chain fatty acids and total acid content and increased the WSC content. Compared with FA and FS, FF significantly increased the WSC content. DM losses from FA and FF treatment were significantly less than C but not FS. Additive treatment significantly increased silage DM intake and liveweight gain compared with C. It is suggested that additive treatment irrespective of the nature of the formic acid applied produced well-fermented silage, which when fed to growing cattle significantly increased both silage DM intake and liveweight gain compared with non-additive-treated silage. (C) 1998 Silsoe Research Institute.