Published online by Cambridge University Press: 02 September 2010
In two feeding experiments, an untreated silage which had received no additive was compared with silages which had received either formic acid (‘Add-F’) or a formalin and sulphuric acid mixture (‘Sylade’). The ‘Add-F’ was applied at the rate of 3·81/t and ‘Sylade’ at the rate of 3·1 1/t of fresh herbage harvested from a perennial ryegrass and white clover sward.
The silages were offered ad libitum to 30 British Friesian male calves (mean fasted live weight 97 kg) in Experiment 1 and to 27 steers (mean fasted live weight 320 kg) of mixed breed in Experiment 2. Concentrate was offered to the animals in Experiment 1 at the rate of 0·86 kg dry matter/head per day.
In each experiment the intakes of dry matter and digestible organic matter were higher from the additive-treated silages than from untreated silage.
In Experiment 1 the application of ‘Sylade’ increased significantly (P < 0·05) the mean daily unfasted live-weight gain (0·87 kg/day) over that for animals offered untreated silage (0·74 kg/day). In Experiment 2 the mean daily unfasted live-weight gains from ‘Sylade’-treated (0·70 kg/day) and ‘Add-F’-treated silage (0·78 kg/day) were significantly higher (P<0·01) than that from untreated silage (0·38 kg/day).