pseudoruminanten

Pseudoruminants, or pseudo-ruminants, are a group of foregut-fermenting herbivores distinguished by a three-chambered stomach rather than the four-compartment stomach of true ruminants. In these animals, microbial fermentation of fibrous plant material occurs mainly in the foregut, followed by enzymatic digestion in the glandular stomach. They may also regurgitate and chew cud, a process known as rumination, to improve fiber breakdown.

The best-known members of this group are the camelids—camels (Old World), llamas, alpacas, vicuñas, and guanacos. They inhabit a range of environments, including deserts, high plains, and mountainous regions across Africa, Asia, and the Americas. Their three-compartment stomach is often described in terms of C1, C2 and C3, with C1 and C2 housing fermentation and C3 serving as the true stomach for enzymatic digestion. Unlike true ruminants, which have a distinct omasum, pseudoruminants lack a separate omasum.

Taxonomic placement places camelids within the order Artiodactyla, in the suborder Tylopoda, making them distinct from the typical ruminants (Ruminantia). Their digestive strategy, dental structure, and dentition enable them to utilize coarse, low-quality forage typical of their native habitats, contributing to their ecological and agricultural roles.

In human contexts, several camelids are domesticated for transport, fiber (such as wool from llamas and alpacas), meat, and pack use. The term pseudoruminant is more common in older zoological literature; in modern usage, camelids are often described as having three-chambered foregut fermentation.