Comparative morphology of the diaphragm of white tufted-ear marmoset and the white-fronted marmoset

Abstract

The marmosets of the Callithrix genus have a great importance in the research field, not only for its occurrence in the ecosystems of South America and Central America, but also because of its small size and easy management. This study aimed to characterize the ultrastructure of the diaphragm of four adult animals of the C. jacchus species and four animals of the C. geoffroyi species that died from natural causes. Diaphragms were collected, dissected, and fixed in 10% formaldehyde and analyzed through scanning electron microscopy. It was observed the presence of an external membrane of connective tissue, with cylindrical muscle fibers arranged in rows perpendicular to the longitudinal axis and grouped into fascicles. In C. jacchus it was observed a discontinuous and linear fibers’ architecture, resulting in a score of 7 and 8 fascicles for male and female, respectively. In C. geoffroyi the fiber had a continuous shape, but also linear, yielding a total of 9 and 6 fascicles for male and female, respectively. The architecture of muscle fibers and the count of fascicles of the coastal face of the diaphragm suggest differences between the species C. geoffroyi and C. jacchus and between males and females, intra- and interspecies.

Keywords

• Diaphragm
• Marmoset
• Primates
• Scanning electron microscopy
• Veterinary anatomy