How much back fat should a lamb have? September 11, 2022December 28, 2023BRA 0 Depending on breed and frame size of the lamb, most animals will achieve the desired level of back fat or finish (between 0.16 and 0.25 inches) at a live weight between 125 and 145 pounds.Related Posts:What is the desired fat covering on a market lamb?Strengthen Your Back Muscles & Shape Your Back -…Goodbye Back Flab, Hello Sleek Back: The Best Back Fat