The previous edition of this publication added 6% wastage to the feed requirements. This allowed for feed that was offered to cows under good grazing conditions but was not eaten by the cows. In research trials 6% of the feed offered to cows disappeared, but was not accounted for by milk production or liveweight change, so is assumed to be lost in the grazing process. Farmers should be aware that cows are unlikely to eat all the feed they are offered.
Wastage always occurs, the extent of wastage being dependent on grazing conditions and the type of feed being offered. To meet the expected energy requirements of cows, farmers should allow for some of the feed offered being wasted (not eaten by the cows).