Gross Morphological and Biometrical Sexual Dimorphic Studies on the First, Second and Third Pairs of Ribs of Blue Bull (Boselaphus tragocamelus)

The present study was carried out on the first, second and third pairs of ribs of six specimens of adult Blue bull (Boselaphustragocamelus) of either sex. These ribs had a head, neck and a tubercle at the proximal end, shaft or body and a costal cartilage at the distal end. An accessory tubercle was located below the main tubercle of the ribs at their caudal border of the shaft. The accessory tubercle was located 4.1±0.08 cm and 4.2±0.11 cm below the proximal tubercle at the caudal border in females and males respectively. The costal groove was prominent at the proximal aspect of the caudal border of the second rib. The accessory tubercle was absent in the second rib. The accessory tubercle was located 3.3±0.13 cm and 3.5±0.10 cm below the proximal tubercle at the caudal border in females and males respectively. The curviness of the shaft increased up to the 3^rd rib. The ribs of both the sides had similar structures and sex wise gross variations were not found. The Biometrical observations on different parameters of first, second and third pairs of ribs of Blue bull reflected significance (P<0.05) differences between the sexes of this species. The present study would be helpful in identification of the first three pairs of ribs of Blue bull and solving vetero-legal cases related with this species.