To find the salivary glands, you must turn the fetal pig on its side first to get a better view of its cheeks. Then carefully cut through the skin along the side of the head between the ear and the mouth. Separate the skin from the underlying tissues and remove it to expose more of what is underneath. The platysma and other muscles associated with the skin are also removed to expose the salivary glands and ducts. This is to be don’t very carefully since the structure to be examined lie directly below the skin.
Parotid Gland — This is the largest of the salivary glands. It lies ventral to the pinna (external ear) and is recognized by its triangular shape and lobular texture. The parotid duct, can be seen emerging from the anterio-ventral edge of the gland by several roots. It then crosses the lower portion of the masseter muscle of the cheek, following the course of the prominent external maxillary vein. It continues to the mouth and opens opposite the upper fourth molar. You can find the opening by looking inside the cheek and tugging lightly on the duct with forceps.
Submandibular Gland — Most of this gland lies beneath and ventral to the parotid gland just posterior to the angle of the jaw. It is small and oval in shape. Separate the two glands. Its duct is hard to trace since it passes amongst some of the jaw muscles. It extends to the angle of the jaw, passes to the floor of the mouth, to the anterio-ventral connection of the tongue. At this point it opens into the mouth.
Sublingual Gland — This is the third salivary gland. It is flat and narrow and lies along the duct of the submandibular gland. Its duct parallels that of the submandibular and both open under the tongue, along its side.
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