Wilting of grass prior to ensiling has been widely adopted as a means of improving the fermentation quality of silage. However, the effects on intake have been variable. For example, with growing cattle, Rohr and Thomas (1984) reported that wilting increased silage dry matter (DM) intake by 0.09, while Steen (1984) reported an increase of 0.18. Similarly with lactating cattle, Rohr and Thomas (1984) reported and increase in intake in response to wilting of 0.04, while Patterson, Yan, Gordon and Kilpatrick (1997) observed an increase of 0.20. However, a range of additives were used in these studies and it is suggested that this may have caused variation in the fermentation quality of the unwilted silages which in turn may have affected the response to wilting. Consequently an experiment was designed to determine if the variability in the intake responses to wilting could be explained by differences in the fermentation characteristics of the unwilted silage.