Abstract

There is a scarcity of published data regarding embryonic development in rabbits. The current study was conducted to evaluate the development of the stomach in rabbit fetuses and the expression of the transcription factor GATA4 during different stages of development. This study was conducted on 40 rabbit fetuses for morphology, histology, and GATA4 expression. The rabbits used were seemingly healthy white New Zealand pregnant females (aged 1.5-3 years and weighing 2 - 4.5 kg). The morphology and histology of rabbit fetuses’ stomachs (22 fetuses) were examined using a light microscope on days 10, 12, 13, 14, 16, 18, 20, 22, and 26 of the rabbit’s gestation period. The expression of GATA4 in rabbit fetuses (18 fetuses) on developmental days (20, 22, and 26) was investigated using quantitative real-time PCR (qRT-PCR). The results indicated that the initial stomach appeared as a fusiform widening in the posterior part of the foregut on day 10. The mucous membrane was significantly thickened, and the formation of the gastric gland commenced on day 18. On day 22, the lining epithelium transformed into the pseudostratified epithelium, and the mucosal folds exhibited more clarity. On day 26, the lining epithelium of the stomach had changed into a simple columnar epithelium. Additionally, the mucosal folds and gastric pits were fully developed in all stomach areas. The stomach glands displayed exceptional transparency and were fully developed. Analysis of qRT-PCR data showed a significant increase in GATA4 mRNA expression in the embryonic stomach on gestational days 20, 22, and 26 as the pregnancy progressed. In conclusion, this study comprehensively described the morphological and histological development of the rabbit stomach. It demonstrated a substantial upregulation of GATA4 mRNA expression as gestation advanced, indicating its crucial role in stomach development. © The Author(s) 2025. This article is licensed under a Creative Commons Attribution 4.0 International License https://creativecommons.org/licenses/by/4.0/.