Which stomach chamber is referred to as the true glandular stomach in ruminants?

The abomasum is referred to as the true glandular stomach in ruminants because it is the chamber where the digestion of food occurs in a manner similar to that in monogastric animals. This chamber secretes digestive enzymes and gastric juices, allowing for the breakdown of proteins and other complex nutrients. Unlike the other stomach chambers in ruminants, such as the rumen, omasum, and reticulum, which primarily serve to store, ferment, and help in the mechanical breakdown of feed, the abomasum has a role more akin to the stomach of non-ruminant animals.

The rumen, primarily involved in fermentation and microbial digestion, serves as the primary site for the breakdown of fibrous plant material but does not have the same glandular function. The omasum acts as a filter for food particles and absorbs water and nutrients, while the reticulum is involved in mixing and transferring food but does not perform enzymatic digestion. Hence, the abomasum stands out as the chamber where enzymatic digestion takes place, confirming its designation as the true glandular stomach.