Vertebral Column, Rib and Sternal Muscles of Sulawesi Babirusa (Babyrousa celebensis)

Abstract

The muscular anatomy of the vertebrae, ribs and sternebrae of the Sulawesi Babirusa (Babyrousa celebensis) is described. There are many similarities to the anatomy of the domestic pig (Sus scrofa). However, unlike other pigs, the M. spinalis et semispinalis cervicis et thoracis has an origin from the twelfth thoracic mamillary process. Similarly, the Babyrousa does not have the lumbar part of the M. obliquus internus abdominis which is found in other pigs. The M. sacrocaudalis dorsalis medialis of the Babyrousa is not fused to the Mm. multifidi, and the origin of the M. obliquus externus abdominis in the Babyrousa does not include rib 4 or the fascia thoracolumbalis. In the Babyrousa, the M. longissimus atlantis is clearly separated from the M. longissimus capitis, whereas in Sus the two are fused and have a more caudal origin (up to the second thoracic vertebra). The M. longissimus cervicis of the Babyrousa has a less extensive origin and insertion than is found in the domestic pig which may be related to differences between each species in its ability to dig with its nose.