This study presents the morphological characteristics of the excretory ducts of the parotid salivary gland in rats during the transition to definitive feeding and the onset of puberty. Light microscopy and morphometry were used to study the structure of the epithelial layer, wall thickness, and lumen diameter of the ducts. The data obtained indicate age-related morphofunctional changes associated with the adaptation of the salivary glands to various physiological conditions. This study expands our understanding of the development of exocrine glands during ontogenesis and their structural adaptation to changes in diet.

Morphology, rats, parotid gland, excretory ducts

Books and monographs:

• Ivanov I.I. Morphology and physiology of salivary glands in mammals. - Moscow: Nauka, 2015. - 320 p.

• Petrov P.P., Sidorov S.S. Fundamentals of histology and morphology of endocrine glands. - St. Petersburg: Piter, 2018. - 275 p.

Articles from magazines:

• Smith J., Brown L. Morphological changes in rat salivary glands during development // Journal of Morphology. — 2020. — Vol. 281, No. 3. - P. 345–357.

• Zhang H., Li Y. Age-related changes in exocrine gland structure in rats // Anatomical Record. — 2019. — Vol. 302, No. 1. - P. 120–128.

Internet sources (if any):

• WHO. Nutritional transition in mammals: implications for glandular morphology. URL: https://www.who.int/nutrition/mammals_glands (accessed: 20 October 2025).