Comparative Anatomical Study of the Thoracic Limb Skeleton in the Chinchilla (C. Lanigera) and in the Domestic Rabbit (O. Cuniculus)

The current growing trend of Chinchilla husbandry for pets creates a demand for generating a detailed anatomic data base of this species. Taking into account the existing initiatives of osteology and osteometry research our study aimed to compare the pelvic limb skeleton of the Chinchilla to that of the Domestic Rabbit, in order to highlight the differences.10 pelvic limb skeletons of adult Chinchillas were compared to 10 Domestic Rabbit pelvic limbs skeletons belonging to our ossuary. Examination underlined several particularities: the wing of the chinchilla’s ilium is narrower than that of the rabbit’s, the gluteal crest is very prominent and continues on the lateral side of the neck of ilium, ending in a tubercle, caudally to the acetabulum. The femur misses the third trochanter present in rabbits. The tibia and the fibula of the Chinchilla are not fused in the distal two thirds of the diaphysis. The Chinchilla’s fibula is a complete bone, having the same length as the tibia, ending by a rounded lateral malleolus. The similitude to the Rabbit is that the two bones present a visible but narrow proximal interosseous space. Both species present a similar autopodium, although the fifth toe is shorter in Chinchillas, composed of two phalanges. In conclusion, the coxal, the femur, the tibia and fibula of the Chinchilla present several distinct elements when compared to Domestic Rabbits, which provide details useful for clinical examination and further articular and muscular research in this species.