Prenatal development of submandibular salivary gland of New-Zealand rabbits

Abstract

The present study aimed to ellucidate the prenatal developmental stages of the submandibular salivary gland of the New-Zealand rabbits. To conduct that, twenty New-Zealand rabbit fetuses ranged from 11 to 30 days-old were used. The head region of fetuses and gland specimens were fixed, processed and stained with histological stains to be examined by light microscope. The submandibular primordia was firstly seen at the 12 th day of the prenatal life as bilateral invaginated epithelial buds from the linguo-gingival groove. At 15 days-old , such buds continued deep down growth forming cord-like structure ended by compact bulges that forming the future primitive acini. At 17 days, such cords were branched off forming the future primary ducts. Canalization of the ducts appeared at 18 days. At 22 days, the primitive capsule initiated around the gland and the lobulation was recognized. At 25 days, the capsule became well developed, the duct system was completed and the parenchyma occupied by serous adenomeres surrounded by myoepithelial cells. At the full term, the submandibular gland became fully developed and became typically compound tubulo-acinar nature, the parenchyma showed seromucoidadenomeres. Strong positive PAS reaction was noticed in the striated ducts, while the cytoplasm of the acinar cells reacted weakly.