The objective of this study was to develop and
compare alternative prediction equations of lean meat proportion
(LMP) of lamb carcasses. Forty (40) male lambs, 22 of Churra
Galega Bragançana Portuguese local breed and 18 of Suffolk breed
were used. Lambs were slaughtered, and carcasses weighed
approximately 30 min later in order to obtain hot carcass weight
(HCW). After cooling at 4º C for 24-h a set of seventeen carcass
measurements was recorded. The left side of carcasses was dissected
into muscle, subcutaneous fat, inter-muscular fat, bone, and
remainder (major blood vessels, ligaments, tendons, and thick
connective tissue sheets associated with muscles), and the LMP was
evaluated as the dissected muscle percentage. Prediction equations of
LMP were developed, and fitting quality was evaluated through the
coefficient of determination of estimation (R2
e) and standard error of
estimate (SEE). Models validation was performed by k-fold
crossvalidation and the coefficient of determination of prediction
(R2
p) and standard error of prediction (SEP) were computed. The
BT2 measurement was the best single predictor and accounted for
37.8% of the LMP variation with a SEP of 2.30%. The prediction of
LMP of lamb carcasses can be based simple models, using as
predictors the HCW and one fat thickness measurement
