title: The estimation of beef carcass muscle using cross-sectional area of M. longissimus dorsi at the fifth rib.
abstract: The improvements in the accuracy of prediction of side muscle (weight and proportion) using measurements of eye muscle area at the 10th rib (EMA(10)) and eye muscle area at the 5th rib (EMA(5)), were compared in 48 steers, grain-fed for the Japanese market. For side muscle proportion the addition of EMA(10) to hot side weight and a fat thickness measurement did not improve prediction but the addition of EMA(5) did. P8 fat thickness together with hot side weight and EMA(5) (each, P<0·001) predicted side muscle proportion with an SEE of 2·05% and an R(2) of 61%, while the values for 10th rib thickness together with hot side weight and EMA(5) (each, P<0·001) were 2·09% and 68%, respectively. For the prediction of side muscle weight a fat thickness measurement and hot side weight (both, P<0·001) explained 77-84% of variance; the addition of an eye muscle area measurement further improved prediction with the most accurate being P8 fat thickness together with hot side weight and EMA(5).
authors: Department of Farm Animal Medicine and Production, The University of Queensland, P.O. Box 125, Kenmore, Queensland, 4069, Australia.
authors: E R
authors: ER
authors: Johnson
authors: D G
authors: DG
authors: Taylor
authors: R
authors: R
authors: Priyanto