Abstract
Background:
The study of the peculiarities of the anatomy of sheep and rabbits digestive systems is an important way to improve the efficiency of this animals' breeding.
Aim:
The aim of the presented research was to study structural changes of such digestive glands as the liver and the pancreas which occur in the process of ontogenesis in sheep and rabbits.
Methods:
Sheep of the “Kazakh fat-tailed semi-coarse-wooled” breed (n=8) raised in the “Sayan” private peasant agriculture and rabbits of the “Grey Giant” breed (n=8), raised on the mini rabbit farm of the Agriculture Faculty of Shakarim University were used in the research
Formed two experimental animal groups (of sheep, “Kazakh fat-tailed semi-coarse-wooled” breed, n=8; rabbits, “Grey Giant” breed, n=8). The liver and pancreas' ontogenesis development has been studied in these animals.
Results:
The study presents a holistic view on a macro-microscopic structure of the liver and the pancreas of animals in crucial age periods, stages and phases of postembryonic ontogenesis (by the example of sheep and rabbits). The authors have traced age stages of adaptive change and structural-functional change of stromal-parenchymatous structures of the liver in sheep and rabbits taking into account stages and crucial phases of development.
Conclusion:
Development of the liver and the pancreas are characterized by a discontinuous growth in the process of postnatal ontogenesis. A crucially important period is the first months after the birth, during which the weight and functionality of these organs grow rapidly.

Key words: Digestive glands, Langerhans islets, Liver, Pancreas, Microstructure