Gross morphological and sex wise morphometrical studies on the tenth, eleventh, twelfth and thirteenth thoracic vertebrae of Blue bull (Boselaphus tragocamelus)

摘要

The present study was carried out on the tenth, eleventh, twelfth and thirteenth thoracic vertebrae of six specimens of adult Blue bull (Boselaphus tragocamelus) of either sex. The tenth, eleventh, twelfth and thirteenth thoracic vertebrae were characterized by long supraspinous process, cylindrical, but short centrum. The centrum was distinctly constricted in the middle and presented a thin-edged ventral crest. The arch presented shallow notches and was perforated by intervertebral foramina at its caudal aspect. The mammillary processes were fused with the anterior articular processes in T-12 and T-13 The backward slope of the dorsal supraspinous process decreased from T-10 to T-12. The supraspinous process of T-13 was vertical and wide as lumbar vertebra. The costal facets were placed on either side at the end of the articular extremities of the centrum. However, the posterior costal facets were absent in T-13. Each articular facet was a demi-facet which articulated with the half of the part of the head of the rib. The cranial vertebral notches were shallow and small, but the caudal ones were deeper. The arch was caudally perforated by an additional intervertebral foramen on either side. The cranial articular processes were represented by oval facets on the anterior part of the arch and faced upwards except in T-11 where they were triangular in shape, whereas the caudal ones sprang from the base of the dorsal supraspinous process. The left caudal articular facets of T-13 was placed at a higher level than the right ones.