Morphological Studies of Pectoral Limb Bones in Ostrich (Struthio camelus), Duck (Anas platyrhynchos domesticus) and Domestic Fowl (Gallus gallus domesticus)

Abstract

Pectoral limb bones from adult ostrich, duck and domestic fowl were used in the present study. Scapula, clavicle and coracoid were fused together in ostrich. Foramen triosseum was lacking in ostrich. Entire shaft of coracoid was anterio-posteriorly compressed in ostrich, while; only the distal two third was flattened in duck. In domestic fowl, shaft was more cylindrical. An interosseous foramen positioned between coracoid and clavicle was a salient feature of ostrich. Clavicles were thin rod like in domestic fowl, but were flattened in duck and
ostrich. Ostrich lacked a furcula. Clavicles united to form “Y†shaped furcula in domestic fowl wide “U†shaped arc in duck. Hypocleideum was prominent in domestic fowl and was rudimentary in duck. Humerus was not pneumatic in ostrich, while, domestic fowl and duck had a pneumatic foramen. The length ratio of humerus to radius and ulna was 1: 0.32, 1: 0.98 and 1: 0.89 in ostrich, domestic fowl and duck, respectively. Radius was much slender in domestic fowl and duck, while in ostrich, it was well developed.