Animal performance data (e.g. weight, weight gain, feeding situation, and feed digestibility) may be used to estimate the gross energy (GE) intake, which is defined as the daily amount of energy (MJ) an animal requires.

It is good practice to estimate gross energy intake based on animal performance data that is specific to the country and using well documented and recognized country-specific methods. If no CS methods are available, GE should be estimated using the equations in the GPG. Parties should use the corrected equations presented in the GPG.