In animal husbandry
, feed conversion ratio
(FCR), feed conversion rate
, or feed conversion efficiency
(FCE), is a measure of an animal
's efficiency in converting feed mass
into increased body mass.
Specifically FCR is the mass of the food eaten divided by the body mass gain, all over a specified period of time. FCR is dimensionless, i.e.
there are no measurement unit associated with FCR.
Animals that have a low FCR are considered efficient users of feed. Poultry usually can convert 2-3 kg of feed into 1 kg of live weight, while sheep and cattle
need more than 8 kg of feed to put on 1 kg of live weight. Farm raised Atlantic salmon have a very good FCR, about 1.2.
Brown, L., Hindmarsh, R., Mcgregor, R., 2001. Dynamic Agriculture Book Three (2nd ed.). McGraw-Hill Book Company, Sydney.