Previous studies have shown a low efficiency of utilisation of urea treated whole crop wheat (UWCW) when offered as the sole forage to dairy cows (Hill and Leaver 1990). The poor efficiency of utilisation of metabolisable energy could possibly be influenced by the level and quality (the balance in QFN, SFN, and UN) of protein intake by the cow.

To investigate the effect of level and quality of protein intake on the digestibility of UWCW fed ad libitum to lactating cows, an experiment was carried out using three concentrate sources based upon molassed sugar beet pulp pellets (Diet A), soya bean meal (Diet B) and fishmeal (Diet C). A concurrent experiment was implemented to analyse the degradation characteristics of UWCW using sheep.

Six multiparous mid to late lactation Holstein Friesian cows were allocated to two 3x3 latin squares. Each cow was housed in an individual pen and fed UWCW ad libitum once daily and concentrate twice daily. Individual DM intakes of forage, milk production, liveweight and faecal output were estimated for each diet. The degradability trial used the methodology of Paine et al (1982).