Sources of shared variability among body shape characters at marketing age in new zealand white and egyptian rabbit breeds

Abstract

-Body measurements (body length, thigh circumference, shank length and chest width) of 311 rabbits representing three breeds, New Zealand White (NZW), Red Baladi (RB) and Black Baladi (BB) purebreds were subject to factor analysis. The objectives of this study were (a) to disclose the main sources of shared variability among body shape characters, (b) deduce the factors that describe these traits, (c) quantify the breed differences in size and shape and (d) predict live weight at marketing age from orthogonal body shape characters. Body conformation 'shape' appeared to be controlled by common and unique factors. The communalities ranged from 0.80 for chest width to 0.99 for thigh circumference and uniqueness (special factors) made the balance. Compared with local breeds (RB and BB), NZW had higher communality (proportion of variance for a variable that is shared in common by other variables) for chest width and lower communality for thigh circumference and body length. Our findings indicated that most of the common variability in NZW body dimensions could be accounted for by factors representing general size and chest width. Corresponding factors in RB were general size and shank length and those in BB were general size and thigh circumference. Independent body shape characters derived from factor analysis accounted for 83.4%, 87.9% and 90.8% of the variation in live body weight in New Zealand White, Red Baladi and Black Baladi, respectively.

Application of Principal Component Factor Analysis in Quantifying Size and Morphological Indices of Domestic Rabbits

“…However, the highest correlation coefficients were recorded with heart girth and thoracic circumference (0.91 and 0.84). Similar findings have been reported (Shahin & Hassan, 2000;Abdullah et al, 2003). The thigh is the area where there is the highest muscle deposition in the rabbit body (Oliveira et al) hence, its high relationship with bodyweight while the heart girth reflects gut fill.…”

Application of varimax rotated principal component analysis in quantifying some zoometrical traits of a relict cow

“…The variables associated with withers height, back height and rump height had the highest loadings (component-variate correlations), followed by thoracic girth. It corroborates the submission of Pundir et al [8], Salako [10], Shahin & Hassan [11] and Yakubu & Ayoade [13], between others, for whom the PC1 can be considered as a generalized size factor. Similarly, Ruales-España & Perdomo [9] extracted eight principal components from 31 original traits and concluded that these could be of great importance in the determination of body attributes of criole Romosinuano cow.…”

Phenotypic characterization of the indigenous chickens <i>(Gallus gallus)</i> in the northwest of Algeria

“…As for males, the third axis had a high contribution of beak length, which also represented an opposite direction between beak and wattle length. The present findings are consistent with the literature, in which general size is generally reported as the main factor of variation and thus constitutive of the first axis of PCA in chickens, rabbits, or turkeys (Shahin and Hassan, 2000;Ajayi et al, 2011;Egena et al, 2014). The principal component analysis allowed for better understanding of the complex correlations among the traits and reduced the number of traits, using only the three first PCs, without loss of information.…”