Histological observation on cardiogenesis during second trimester of domestic rabbit's fetuses (Oryctolagus Cuniculus)

Abstract

The present work was designed to investigate the histological developmental characteristics of heart in the local rabbit fetuses. It which included the detection of timing of heart beat onset and studied morphohistogenesis of heart components. The study was performed on 35 rabbit fetuses distributed at seven groups according to the following ages: (9, 10, 12, 14, 16, 18, 20) days gestational age. The results of the current study showed that differentiation and formation of the heart began between 9th and 10th day of pregnancy in which the smooth-walled heart loop had an outer myocardial mantle, cardiac jelly and present of endocardium by histological study for serial section in each stage. The histological structures for each age showed that the heart passed through different sequential morphological stages in embryonic life represented by heart tube, looping heart, chamber formation and cardiac septation. The purpose of our study was to provide a more complete histological description of the stages of heart formation in rabbits during prenatal development.