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

Abstract

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 com- munalities 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, fat- ness, 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 mus- cle, total carcass fat and total carcass bone, respectively. factor analysis / tissue variations / rabbits / estimation / multicollinearity