Abstract
Lactation is a complete process of milk synthesis and secretion including development of mammary gland (mammogenesis), initiation of milk synthesis and secretion (lactogenesis), maintenance of milk secretion (galactopoiesis), and restoration of virgin-like mammary gland (involution).
Mammogenesis starts around 32 days of embryonic life but a series of structural and functional development, differentiation, and involution are noticed during different physiological state of animals. Lactogenesis is the biological process of onset of milk secretion which includes the enzymatic and cytological differentiation of mammary alveolar cells in early pregnancy to full lactation after parturition. The mammary gland utilized blood precursors to synthesize various milk components. Galactopoiesis is the maintenance of established lactation which follows a dynamic curve with a rapid accelerating phase, peak yield followed by a declining phage till the end of lactation. The suckling stimulus causes milk ejection from mammary gland by neuro-endocrine reflex. Mammary involution is a biological process to restore mammary gland into a virgin-like state through a series of tissue remodeling processes after the cessation of milk secretion. The interactions of different hormones and growth factors are essentially required in each stage of lactation process.J. Mukherjee (X) ∙ P. K. Das ∙ D. Banerjee
Department of Veterinary Physiology, West Bengal University of
Animal & Fishery Sciences, Kolkata, West Bengal, India
© The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2023
P. K. Das et al. (eds.), Textbook of Veterinary Physiology, https://doi.org/10.1007/978-981-19-9410-4_25
Graphical Abstract
Description of the graphic: Lactation (1) is a complete process of mammogenesis (2), lactogenesis (3), and galactopoiesis (4). The mammary gland is developed from mesoderm through a series of structural and functional differentiation called mammogenesis (2).
Lactogenesis is the biological process of onset of milk secretion which includes the enzymatic and cytological differentiation of mammary alveolar cells together with the synthesis of milk constituents (3). Galactopoiesis is the maintenance of established lactation which follows a dynamic curve with a rapid accelerating phase, peak yield followed by a declining phage till the end of lactation (4). Mammary involution is a biological process to restore mammary gland into a virgin-like state through a series of tissue remodeling processes (5) after cessation of milk secretionKeywords
Mammogenesis ∙ Lactogenesis ∙ Galactopoiesis ∙ Involution ∙ Hormones ∙ Growth factors most advanced form which can produce far more milk than required for a calf. Genetic selection, nutritional strategies, and advanced managemental practices make the mammary gland capable of producing an increased volume of milk.
Learning Objectives
• The external and internal structure of the mammary gland.
• Development of mammary glands during different physiological states.
• Biosynthesis of milk constituents and milk secretion.
• The composition of milk.
• Factors affecting milk yield and composition.
25.1