Pelvis shape analysis with geometric morphometry in crossbreed cats

Abstract

In this study, the geometric morphometry of the pelvis of 32 (16 male, 16 female) crossbreed cats was investigated. Pelvis images of cats were obtained by computerized tomography method. Then, these images were modelled and geometric morphometry was applied. Shape variations of the pelvis of all individuals were obtained by principal component analysis. The first principal component (PC1) value explained 18.44% of the total variation. Second principal component (PC2) and third principal component (PC3) values explained 16.84% and 13.60% of the total variation, respectively. The difference in the shape of the pelvis of female and male cats was more pronounced in PC2 and PC3, which differed in the linea terminalis. The centroid size difference in terms of sex in the Procrustes ANOVA result is statistically insignificant (p > 0.05). However, the shape difference was statistically significant (p < 0.001). As a result of discriminant analysis, the pelvis of female and male cats was completely separated from each other. The crista iliaca of males was more lateral than females. Linea terminalis was wider in shape in females. The edge of the acetabulum was higher in shape in males. Regression analysis was performed to see whether the age and weight of the cats had an effect on the centroid size of the cats. Age and weight were not found to be effective on centroid size. The shape variations of the anatomical formations obtained by geometric morphometry method can be revealed, and it can be examined whether there is a shape difference between the groups.