Because of its high pectin content, citrus pulp provides with readily fermentable energy for rumen microbial synthesis and promotes a more favourable environment for fibre digestion than starch supplements (Barrios et al., 1996). However, we are unaware of data comparing efficiency of microbial synthesis with cereals or citrus pulp. This work compares digestibility and efficiency of microbial synthesis of mixed straw diets with increasing substitution of barley by citrus pulp, at two feeding levels.

Diets included equal parts of ammoniated barley straw (10.5 g N/kg DM) and a concentrate made up by different ratios of barley (18.2 g N/kg DM) and citrus pulp (11.1 g N/kg DM), namely M1 (100:0), M2 (66:33), M3 (33:66) and M4 (0:100).