Gross Morphometry of Pectoral Girdle of Domestic Pigeon (Columba livia)

Abstract

The pectoral girdle gives strength and range of motion to the wings of birds and plays functional role in flight mechanism of birds. Pectoral girdle of adult domestic pigeon (Columba livia) (n=10) was studied with special reference to the morphological and morphometric parameters. The girdle was composed of three pairs of bones viz. the scapulae, the coracoids and fused clavicles (furcula). The scapula was sword shaped with proximal extremity and a blade. The length and maximum width of scapula were 4.23 cm and 0.56 cm, respectively. The clavicle was in the form of thick curved plate to join the bone of opposite side forming the broad 'U' shaped furculum with rudimentary hypocleideum. The width of clavicle gradually decreased from proximal to distal end. Hypocleideum was not prominent at their meeting point. The curvature length and maximum width of clavicle were 6.38 cm and 1.61 cm, respectively. Coracoid was directed downwards and backwards to articulate the sternum distally. The length was 3.53 cm and width of distal extremity (1.45 cm) was about twice that of proximal one (0.70 cm). The proximal extremity of coracoid was hook like and articulated with proximal extremity of scapula and clavicle to form foramen triosseum (0.35 cm diameter).