Multiple choice The definition of FCR is: An animals efficiency at turning only silage mass into LWG An animals efficiency at turning water mass into LWG An animals efficiency at turning food mass into LWG An animals efficiency at turning food mass into fat Reveal answer Fill a bubble to check yourself C Correct answer Explanation Feed Conversion Ratio (FCR) is a measure of an animal's efficiency in converting feed mass into live weight gain (LWG). A lower FCR is desirable because it means the animal requires less feed to produce a kilogram of weight gain.