Sources of shared variability of muscle, fat and bone weight distribution in new zealand white rabbits

A factor analysis with a varimax rotation was applied to 17 highly intercorrelated muscling, fatness and bone traits on 72 male New Zealand White rabbits to disclose the main sources of shared variability, deduce the factors that describe muscle, fat and bone distribution and predict total carcass muscle, fat and total carcass bone from orthogonal muscling, fatness and bone traits. Muscle, fat and bone weight distribution appeared to be controlled by common and unique factors. The communalities ranged from 0.38 (neck bone) to 0.91 (hind leg muscle) and the uniqueness (special size factors) made the remaining variances. The shared variability of structural tissues (muscle and bone) was higher than that of fatty tissue. Our findings indicate that most of the common variability (74%) in muscle, fat and bone weight distribution can be accounted for by factors representing fatless, fatness, neck muscle and fat (boneless neck) factors. Differences and similarities between rabbits and other meat-producing species (Pekin ducklings and Japanese quail) in factors describing variations in muscling, fatness and bone traits are discussed. Independent muscling, fatness and bone traits derived from factor analysis accounted for 95%, 97% and 95% of the variation in total carcass muscle, total carcass fat and total carcass bone, respectively. factor analysis / tissue variations / rabbits / estimation / multicollinearity Rsum -Sources de variabilit commune dans la rpartition pondrale des muscles, du gras et des os chez le lapin New Zealand White. Une analyse factorielle utilisant une rotation varimax a t applique 17 variables musculaires, adipeuses et squelettiques mesures sur 72 lapins de race New Zealand White afin (i) d'identifier les principales sources de variabilit commune, (ii) de dterminer les facteurs contrlant la rpartition des muscles, du gras et des os et (iii) de prdire la masse totale de muscles, de gras et d'os de la carcasse partir des caractristiques orthogonales. La rpartition pondrale des muscles, du gras et des os semble la fois contrle par des facteurs communs et des facteurs spcifiques. Les parts de variance dues aux facteurs communs sont comprises entre 0,38 (os du cou) et 0,91 (muscle des pattes postrieures) et les facteurs uniques (facteurs spcifiques du format) font le complment 1. La variabilit commune des tissus structuraux (muscles et os) a t plus leve que celle des tissus adipeux. Nos rsultats indiquent que l'essentiel de la variabilit (74 %) de la rpartition pondrale des muscles, du gras et des os peut tre attribu trois facteurs