Cecum and large colon
The caecum and the large colon together form the horse's large fermentation chamber, where the fibre is digested.
General information, not individual feeding or ration advice. For your own horse, consult your vet or a nutritionist.
How does it work?
The caecum and the large colon together, also called the hindgut, form the largest part of the digestive tract. The caecum works as a big mixing vat in which micro-organisms ferment the fibre. This produces volatile fatty acids that the horse takes up as its main source of energy, plus B vitamins. The hindgut is also a large water reservoir, and feed stays there for a long time, up to several days, to ferment thoroughly.
Why it matters
The hindgut turns grass and hay into usable energy while also holding a water reserve. Precisely because the fermentation runs on a delicate microbial balance, a stable, fibre-rich ration is so important.
Common misconceptions
- Digestion does not end in the small intestine; the fibre digestion in the hindgut provides most of the daily energy.
- The large intestine is not a passive drainpipe, but an active fermentation chamber.
What to watch for
The hindgut is sensitive to sudden feed changes and to a large starch load that reaches the large intestine. Both can kill off the gut flora, lower the acidity and increase the chance of colic and laminitis. So always change feed gradually.
Discover more
Sources: Ohio State University Extension · Iowa State University Extension.