Cellulose Digestion in Ruminants
The digestive system of ruminant animals such as cow, goat, buffaloes or sheep exhibits pre‐gastric fermentation. This means the site of microbial digestion and anaerobic fermentation of cellulose occurs before digesta reaches the small intestine, the place in the digestive tract where nutrients are absorbed by the body for productive function.
Ruminants are a group of mammals, including cows, sheep, and deer, that have a unique digestive system with four compartments: the rumen, reticulum, omasum, and abomasum. They are animals which chew the cud, which is unchewed grass taken into the rumen which is returned to the mouth for chewing (regurgitation). Reticulum is responsible for regurgitation, forcing the cud back into the cow’s mouth as part of rumination.
The rumen is the largest compartment of the ruminant digestive system. It serves to store partially digested food, provides physical mixing of digesta with ruminal fluid, and is an anaerobic fermentation chamber. The ruminant and ruminal microbes possess a symbiotic relationship. First, the ruminant provides the perfect home for those microbes i.e., an anaerobic environment, perfect temperature and abundance of food. The microbes break that food down, including cellulose, which would be otherwise useless to the animal, and then use nutrients for their own growth. Eg. Fibrobacter succinogenes, Ruminococci .
Also Read: Human Digestive System
Cellulose In Digestion – Herbivores, Termites, & Ruminants
Cellulose is a type of fiber that cannot be digested by the human digestive system. The presence of beta-acetal linkages in cellulose distinguishes it from starch and determines its digestion. The organisms that are capable of digesting the cellulose with their cellulase enzyme are microorganisms such as bacteria, fungi, and protozoa.
Except for a few multicellular organisms, such as termites, most higher organisms cannot digest cellulose without the help of microorganisms. In this article, we will discuss cellulose in digestion and why humans can digest starch but not cellulose.
Table of Content
- What is Cellulose?
- Structure of Cellulose
- Cellulose Digestion in Ruminants
- Cellulose Digestion in Termites
- Cellulose Digestion in Herbivores
- Reasons Why Humans Cannot Digest Cellulose
- Importance of cellulose in digestion
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