Comparative analysis of paw pad structure in the clouded leopard (Neofelis nebulosa) and domestic cat (Felis catus).

The Clouded leopard (Neofelis nebulosa) is a medium-sized highly arboreal cat. This study compares the structure of the digital, metacarpal and metatarsal pads of the manus and pes in N. nebulosa to that of the domestic cat (Felis catus). Covered by a stratified squamous cornified epithelium, the pads have a supple deposit of subepidermal fat that is partitioned by collagen fibers and extensively anchored to the muscle tendon sheaths. In both animals, a pes metatarsal pad suspensory ligament originates from the Mm. flexores digitorum profundi tendon and forms 3-4 small branches that project through the dermal fat layer and attach to the pad epidermis. In the cat manus, four tendons of equal size extend from the M. flexor digitorum superficialis (FDS) to form the manica flexoria in digits 2-4 from which extends a metacarpal pad suspensory ligament (MPSL) on digits 2 and 5 that extends into the tela subcutanea and epidermis. On digits 3 and 4 MPSL extends directly from the FDS tendon itself. In contrast, manus FDS tendons 1 and 5 in N. nebulosa were thin and either project directly to the tela subcutanea (tendon 1) or connect with the manica flexoria forming a metacarpal pad suspensory ligament (tendon 5). Tendons 2-4 connect with the manica flexoria from which MPSL project into the tela subcutanea and epidermis. In both species, the suspensory ligaments may serve to contract the pad to conform to the under lying substrate, thus enhancing the animal's ability to grip branches while climbing.