To estimate an organisms total growth efficiency you need to know the complete feed ingestion from birth till death, the complete cellular metabolism and the total amount of feces released.

的energy used to stay alive without any growth is called energy used for maintenance.

An approximation can be made using respiration and calculations of metabolism

Where G_Eis Growth Efficiency

F_Iis Food Intake

F_Ois Feces

M_Eis Metabolism

Units used for calculating the growth efficiency of an organism are joules, which is the SI-unit of energy.

Metabolism can be estimated via the respiration of an organism