Indissoluble cell wall components (cellulose, lignin, some hemicelluloses and pectin) can slow down the fermentation speed. Consequently, the disappearance speed slows down, while the volume of the contents in the large intestine increases.
By adding grain to a ration of hay, the number of anaerobe bacteria will increase in the elephants caecum and colon. These anaerobe bacteria take care of the digestion of the cell wall carbohydrates.
Caecum acidosis will occur less often than rumen acidosis (acidification of the rumen)
The reason for this is that the elephants feed first passes through the stomach and small intestine before it ends up in the caecum and the colon.