Abstract
Background:
The largest portion of the dromedary camel’s stomach, known as Compartment 1, plays a vital role in the microbial fermentation of ingested food.

Aim:
This study aimed to investigate the prenatal development of Compartment 1 in camel fetuses during the three gestational trimesters.

Methods:
Stomach samples were collected from 21 healthy camel fetuses of both sexes at various gestational ages (79–390 days). The samples were fixed in 10% buffered formalin and histologically examined.

Results:
The primitive stomach wall consisted of three layers in the early first trimester (79 days): epithelial, pluripotent blastemic tissue, and myoblastic. By 87–115 days, the wall displayed smooth to undulating surface regions and comprised four layers: epithelium, lamina propria-submucosa, tunica muscularis, and serosa. At 120–128 days, the smooth surface region of Compartment 1 was lined with stratified epithelium comprising a basal layer of cuboidal cells and 2–3 layers of lightly stained polyhedral cells. In contrast, the undulating surface was lined with pseudostratified columnar epithelium. During the second trimester (163–234 days), the smooth surface region differentiated into a nonglandular zone composed of three layers: stratum basale, spinosum, and granulosum. The folded surface developed into a glandular region characterized by multiple folds and deep pits forming chamber-like structures. These folds exhibited distinct epithelial linings: stratified epithelium at the apices, pseudostratified epithelium on the lateral sides, and simple columnar epithelium in the chambers. In the third trimester (270–390 days), a superficial layer of squamous cells forming the stratum corneum appeared above the three epithelial strata in the non-glandular region. Additionally, the glandular region’s lamina propria contained simple tubular glands lined by simple columnar epithelium.

Conclusion:
Compartment 1 of the dromedary camel undergoes marked histological differentiation throughout gestation, evolving from a simple three-layered wall to a highly specialized organ. Notably, the apical folds develop lateral vertical projections in the glandular region where the stratified epithelium transitions into the pseudostratified epithelium, demonstrating regional specialization and functional differentiation.

Key words: Compartment 1; Dromedary camel; Glandular and non-glandular regions; Histology.