Brewery and distillery co-products such as Brewers Grains and Draff have long been recognised as effective forage replacers within cattle rations. Recently the value of these feeds as concentrate replacers has been demonstrated (Hyslop and Roberts 1990, Forbes and Johnson 1990) with 4kg of concentrates being typically replaced by 16kg of Brewers Grains or Draff within dairy cow rations.

Moist wheat distillers grains (Supergrains) contain higher levels of dry matter, energy and protein compared to Brewers Grains or Draff. At the single distillery producing the co-product, the main raw material used is wheat with a small quantity of malting barley to assist in the enzyme conversion of starch. The cereals and yeast used in the process pass through the entire fermentation and distillation process with the material left after the spirit has been distilled off being concentrated by centrifugation to form Supergrains with a dry matter (g/kg), metabolisable energy (MJ/kg DM) and crude protent content (g/kg DM) of 260, 14.0 and 320 respectively..The objective of this work was to evaluate the effect of replacing concentrates with Supergrains with bulls fed ad libitum grass silage.