A comparison of methods for estimating the metabolisable energy of a sample of grass meal

1. The inclusion of grass meal in the diets of broilers and laying hens reduced food intake and, as a consequence, the apparent metabolisable energy (AME) and nitrogen‐corrected AME (AME_N) values estimated for the grass meal were artificially low.

2. With young broilers the AME and AME_N values of a sample of grass meal were estimated to be 5.97 ± 0.45 and 6.05 + 0.46 MJ/kg dry matter respectively.

3. With adult laying hens the AME and AME_N values of the sample of grass meal were estimated to be 5.36 ± 1.04 and 6.26 ± 0.96 MJ/kg dry matter respectively and the corresponding true metabolisable energy (TME) and nitrogen‐corrected TME (TME_N) values were shown to be 9.12 ± 1.25 and 8.66 ± 1.33 MJ/kg dry matter.

4. It was further illustrated that if the dietary intake of the adult birds had been 100 g/d, the AME value of the grass meal would have been estimated as 8.33 MJ/kg dry matter.