Metabolizable energy (ME) was calculated accordingto the equation described by Robinson et al. (2004) as: ME (MJ/kg DM) = 0.82 × (((2.4 × CP) + (3.9 × EE) + (1.8 × organic matter) × in vitro organic matter digestibility (ivOMD)); where CP, EE and OM are in g/kg DM and ivOMD values obtained from our previous in vitro study with mean values of 540 g/kg DM.