Investigation of the microstructure and mechanical properties of the domestic cat’s paw pads

Abstract

Domestic cats have a biological function such as cushioning when they are jumping or walking which is mainly due to the biological coupling system formed in the long-term evolution process of nature, including the trunk-leg-paw pad structure. Among them, the paw pad, as the only part of the body that directly contacts with the ground in the process of movement, plays a key role in its biological function. Hence, in order to clarify the micro structure, mechanical properties and functional characteristics of the paw pad and reveal the relationship between it and the domestic cat’s biological function, this paper has carried out an in-depth research on the histological structure and mechanical properties of the domestic cat paw pad, including observation by tissue staining, scanning electron microscopy and quasi-static compression test. The results show that: the histological structure of the paw pad presents a three-layer coupling structure and has different material mechanical properties, such as the rigid elasticity of the stratified epithelial layer, the viscoelasticity of the dermis layer and the hyperelasticity of the subcutaneous tissue layer. At the same time, the paw pad of the domestic cat has the characteristics of variable stiffness and the stiffness value is low in the early stage of contact, which is conducive to the dissipation of impact energy. It can be seen that the microstructure and mechanical properties of the domestic cat paw pad are of great help in the realization of its function.