Ruminants true digestibility

Ruminants include those animals that we normally think of as cud-chewing, or ruminating animals common examples include cattle, sheep, and goats. The most unusual feature of these animals involves their digestive system, and in particular their multi-compartmented stomach. They are commonly referred to as having four stomachs. The true stomach, that part comparable to the stomach of man, is preceded by 3 other compartments. These are, in order, the rumen, reticulum, omasum, and abomasum. 

TId True intestinal digestibility of non-degraded dietary proteins in ruminants, in... 

Table 13.10 Comparison of estimates of the efficiency of utilisation of truly digested true protein made in some protein evaluation systems for ruminants...

Abomasum The fourth chamber of the ruminant stomach, also called true stomach. The abomasum secretes digestive enzymes and hydrochloric acid. 

It has been claimed that llamas should be superior to the true ruminants in their ability to digest and utilize low protein feeds (Van Saun, 2006 Hinderer and von Engelhardt, 1975). The aim of this study was to investigate (1) if this superiority of the llama can be ascribed to an altered strategy for nitrogen metabolism and excretion from the body, and (2) whether the anatomical distinctive features of the llama foregut is associated with less synthesis and emission of methane from fermentation than in true ruminants. 

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