1. The chemical composition, and amino acid and starch bioavailabilities of 18 triticale varieties were studied. In addition, the water soluble pentosan (WSP) content of 8 varieties was determined. 2. A wide variation in protein (149 to 203 g/kg DM), starch (563 to 629 g/kg DM) and WSP (27.7 to 50.9 g/kg DM) was found between varieties. 3. The TMEn reproductibility was assessed in two laboratories, using Leghorn cockerels, Isabrown cockerels and 3-week-old chicks. There were no significant differences in the TMEn values (range 14.0 to 15.2 MJ/kg DM) between the two types of cockerel. The TMEn values of the varieties were similar for chicks (range 13.6 to 14.9 MJ/kg DM) and for cockerels, with the exception of one variety. 4. The bioavailability of starch (range 96.5 to 99.4%) of some varieties was higher for cockerels than for chicks. The mean bioavailability of amino acids for cockerels was 94.5%. 5. TMEn prediction equations were derived from the chemical composition of the varieties. Best-fit equations were obtained for starch (R2 = 0.62, RSD = 0.24), ash (R2 = 0.58, RSD = 0.25) and WSP (R2 = 0.52, RSD = 0.27).