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 feedmass 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. Sheep and cattle need more than 8 kg of feed to put on 1 kg of live weight. The U.S. pork industry claims to have an FCR of 3.4-3.6 Farm raised Atlantic salmon apparently have a very good FCR, about 1.2.
Tilapia, typically, 1.6 to 1.8.Poultry has a feed conversion ratio of 2 to 1.
Nonetheless this value is an underestimation of the FCR, for it does not take in account that normally the feed is in kg of “dry” weight and the live weight is in kg of “wet” weight. When both factors are transformed to either dry or wet weight the FCR increases 4 to 5-fold, depending on the feeding practice and species; mammal body... Read More