Anatomical and Embryological Development of the Chick Cerebrum in Different Embryonic Periods

The objective of this study is to assess the embryological and morphometric development of the chick cerebrum during specific incubation periods. The cerebrums of 24 Babcock White Leghorn chicks, six each from the 10th, 13th, 16th and 21st days of the incubation period, were used in the study. After removing the heads of fixed embryos from the upper edge of the atlas, the brains were taken out of the cranial cavity. Morphometric measurements were performed on the removed brains, and paraffin blocks were prepared following the routine histological procedure. Sections 5 µm thick were taken from the blocks, with an additional 10 µm thick section taken every 50th section. The slides were then stained using Crossmon's triple stain and Klüver-Barrera staining methods and photographed. The sectional images were transferred to the ImageJ programme, brain volume was calculated using stereological methods, and histological measurements were performed. The development of brain parts in selected embryonic periods was examined in detail, focusing on anatomical and histological aspects. According to the results, it was determined that all measured parameters, except the third ventricle width, increased and were statistically significant (p < 0.05). It is believed that the findings of this study will enhance the understanding of the region's anatomy. The new morphometric data can serve as reference data in neurotoxicity and embryotoxicity studies.