Accuracy of in vivo muscularity indices measured by computed tomography and their association with carcass quality in lambs

• Published in: Meat science Vol. 75; no. 3; pp. 533 - 542
• Main Authors: Navajas, E.A., Lambe, N.R., McLean, K.A., Glasbey, C.A., Fisher, A.V., Charteris, A.J.L., Bünger, L., Simm, G.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.03.2007; Elsevier
• Subjects: accuracy; backfat; Biological and medical sciences; Carcass composition; Computed tomography; Conformation; dressing percentage; Food industries; Fundamental and applied biological sciences. Psychology; in vivo studies; lamb carcasses; lamb meat; lambs; lean meat; Meat and meat product industries; meat composition; meat quality; Muscularity; sarcoplasmic reticulum; Sheep; Sheep; Muscularity; Computed tomography; Carcass composition; Conformation; In vivo; Accuracy; Association; Quality; Meat product; Chemical composition
• ISSN: 0309-1740; 1873-4138
• DOI: 10.1016/j.meatsci.2006.09.007

Assessments of muscle mass and skeletal dimensions by Computed Tomography (CT) enable the development of new muscularity indices for the hind leg (HL) and lumbar region (LR) in lambs. Compared to previous CT muscularity indices, the accuracy was much higher with the new index in the HL (correlations between CT and dissection indices of 0.89 vs 0.51). The accurate measurement of femur length by CT used in the calculation of the new HL index made an important contribution to the higher accuracy of the index. The improvement in accuracy was smaller for the LR (0.55 vs 0.44). The association of CT muscularity indices and carcass quality in Texel and Scottish Blackface lambs showed that improved muscularity is not phenotypically correlated with detrimental effects on carcass composition. CT muscularity indices provide an alternative method to improve carcass conformation and leanness, using measurements that at a constant weight are independent of fatness.