Abstract

The objective of this investigation was to give detailed descriptions of the anatomical location, histological features and histochemical characteristics of the labial and zygomatic salivary glands in mixed breed dogs. This study was performed on five heads of adult mixed breed dogs of both sexes. The heads were dissected to detect in situ position of the labial and zygomatic salivary glands. The glands were dissected and examined grossly. Samples of the glands were taken, processed and stained using hematoxylin and eosin and Masson's Trichrome for histological examination as well as Periodic Acid-Schiff, Alcian Blue (pH 2.5 and 1.0) and a combination of Periodic Acid-Schiff and Alcian Blue (pH 2.5 and 1.0) techniques for histochemical examination. The labial and zygomatic salivary glands were located in the lower lip and in the orbit respectively and they were surrounded by fibrous capsules containing collagen fibers. They were minor, compound, mixed tubuloalveolar glands. They composed of mucous acini, mucous acini with serous demilunes and isolated serous acini. The secretion of the glands (chiefly mucous) consisted of neutral mucins, acid carboxylated mucins and acid sulphated mucins. The duct system of the glands was intralobular (intercalated and striated ducts) and interlobular ducts. The anatomical location as well histological and histochemical structures of the labial and zygomatic salivary glands were important to classify the glands and their secretion as well as to give veterinarians knowledge during clinical examination of the oral and orbital regions, and to recognize normal and pathological conditions.