Interest in milk production from home grown forage has increased in recent years, resulting in a reduction in the amount of compound feed offered. With autumn calving cows there has been a limited amount of work investigating high forage, low compound feeding throughout the winter period. Encouraging results from Trawsgoed over the past 5 years have shown the potential for high forage diets, however reductions in compound feed has consistently resulted in poorer milk quality, particularly milk protein. Experiments conducted by ICI and research workers at Hillsborough, N Ireland have shown favourable responses in milk protein from increasing the compound's protein content. In addition milk butterfat was improved at Hillsborough when the energy content of the compound was increased from 10.8 to 12.9 MJ ME/kg. Unfortunately these trials involved only short feeding periods and were unable to determine long term effects or effects at varying stages of lactation. This experiment examined the effects of both protein and energy concentrations of dairy compound feeds on silage intake and cow performance, when compounds were fed at a flat rate of 3 kg per day to October calving dairy cows throughout a 197 day winter feeding period.