The Department of Pathology, University of Texas Medical Branch and Texas Marine Mammal Stranding Network, Galveston, TX, USA
Poster
The oropharyngeal glands of the Atlantic Bottlenose dolphin, Tursiops truncatus were studied by a systematic histological sampling of the ventral and dorsal surfaces of the oropharynx. All samples were preserved in 10% neutral buffered formalin, embedded in paraffin, sectioned at five microns, and stained with HPS (Hematoxylon, phloxine, and saffron). The oropharynx of the bottlenose dolphin is abundantly supplied with discrete seromucinous and mucinous glands, which taken together constitute a diffuse salivary gland. Compound alveolar glands occur in rows extending from the goosebeak (pharynx) to the base of the tongue ventrally and to the end of the soft palate dorsally. In the posterior oropharynx, glands are incorporated into tonsilar complexes.
Linguopharyngeal grooves were also found on both the ventral and dorsal surfaces of the oropharynx, and glands tend to be distributed along these, as well as in dense array in the mucosa of the hard palate. Openings of the gland ducts tend to be small and easily overlooked in the fresh state, but became more prominent after formalin fixation. Tonsilar tissue was most prominent posteriorly with an increasing concentration of mucous glands becoming more predominant anteriorly. As the tonsilar tissue involuted with age, the secretory elements discharging through crypts became more prominent. Large glands had a maximum depth of 18 mm with long secretory ducts extending from the gland to discharge at the mucosal surface. A complex interdigitation of muscle between glands was noted along the ventral surface only.