Abstract: The gastric groove is a vital part of the digestive system of the suckling ruminants. It consisted of two well-developed lips and a floor between them. The floor of the reticular groove had longitudinal folds and macroscopical papillae. These papillae were randomly dispersed in the proximal parts and clustered at the entrance of abomasum at the point of the reticulo-omasal orifice. A comparative qualitative and quantitative studies were applied on the suckling and the adult goat. The same studies were conducted on the suckling and the adult sheep. In the present study, the mucous glands were found only in the adult sheep. These glands were found in the tunica submucosa at the level of the lips-floor junction, then it was found in the tunica muscularis among smooth muscle fibers of the outer longitudinal layer of the lips. Interestingly, no mucous glands were found in the suckling sheep, the suckling goat and the adult goat. Overall, the present study reveals some interesting facts where the individual layers of the reticular groove have a clear and straightforward development from the proximal to the distal parts with prominent increase with age.