A comparative histological study on the uterovaginal junction in the laying hen in embryonated and non-embryonated egg producers

The uterovaginal junction, part of the reproductive duct, was studied in domestic hens, specifically the special tubular structures known as the sperm host gland. The results were compared between two groups—non-embryonated and embryonated egg producers. Relevant samples were collected, processed to paraffin wax blocks, and sections cut and stained with H&E and PAS stains. Two types of glands were observed in the lamina propria and submucosa. The results from the sperm host glands in chicken’s oviduct suggested that it might have a functional role in oviductal sperm storage in and release of spermatozoa from the sperm host glands of native hens. Sperm storage structures in the form of tubules are observed in the wall of the uterovaginal junction. These tubules are lined by both ciliated and secretory cells and may play a role in the storage of sperm. These features showed better development in the group of egg-laying hens producing embryonated eggs in comparison to the ones producing non-embryonated eggs.