Difference Between Monogastric and Ruminant

Monogastric vs Ruminant

Mammals, being the most developed organisms, possess highly sophisticated digestive systems to feed on a variety of food types available in the world. Monogastric and ruminants are the two main types of mammals based on their types of digestive systems. Most of the mammals fall in the category of monogastrics, yet the ruminants pose a high level of importance for the mammalians and to the entire biosphere. Anatomy, fermentation, and the diet are the main differences between the two types of organisms and those are discussed in this article. 


Monogastrics are the organisms with a simple and single-chambered stomach in their digestive system. The most obvious example for a monogastric would be the humans; however, there are many other organisms of this type such as all the omnivores and carnivores. Rats and pigs are omnivorous monogastrics while cats and dogs come under carnivorous type. However, only a part of the herbivores falls under monogastric category such as rabbits and horses. It would be important to notice that these herbivores are capable of digesting cellulose through microbial fermentation. However, the fermentation process takes place in the hindgut (caecum and colon) of the monogastric herbivores. Small herbivores viz. rabbits have caecal fermentation while large animals such as rhino and horse have colonic fermentation.

The digestive system of monogastrics becomes active during digestion but tends to rest afterwards. Salivation starts as soon as the food being ingested and the digestion starts, which is mainly of two aspects known as mechanical and chemical. The single-chambered stomach secretes enzymes and acids to facilitate chemical diction while the spleen secretes alkali to maintain the pH of the system. Additionally, the gall bladder secretes the bile salts to breakdown fats. The monogastrics are capable of feeding on a variety of foods; hence, their prevalence in the world is dominant.


Ruminants are fascinating creatures in the animal kingdom with the presence of a very interesting digestive system equipped with a four-chambered stomach. Their especially modified stomach is known as the Rumen, and that is the reason for their referred name ruminants. Ruminants are always herbivores as the rumen is developed to digest a herbivorous diet. Cattle, goat, sheep, deer, giraffe, camel, antelopes, and koala are some of the ruminants.

The four compartments of ruminant’s stomach are known as the Rumen, Reticulum, Omasum, and Abomasum. First, the ingested food mixed with saliva is temporarily stored inside the rumen for about four hours where the food is separated into two layers, solid and liquid. The liquid layer is passed into the reticulum, and the solid portion, known as the cud, is regurgitated into the mouth through the oesophagus. The cud is finely ground by the molar teeth of the mouth and is passed back into the stomach. Cellulose particles are broken down into volatile fatty acids while other nutrients are also chemically digested with enzymes. They are called foregut fermenters as the fermentation is taken place in the stomach. The water and inorganic elements are absorbed into blood vessels at the mesum. The abomasum secretes functions almost the same ways as the monogastric stomach and the completely digested food is passed into the small intestine for absorption of nutrients. Ruminants are capable of extracting almost all the nutrients of the food that they feed on, which features an extremely important adaptation for food scarcity with an efficient digestive system.

What is the difference between Monogastric and Ruminant?

• Monogastrics have a single-chambered stomach, but ruminants have a four-chambered stomach.

• Ruminants are always herbivores while monogastrics show all types of food habits.

• The digestive system of ruminants is more efficient than the monogastric system in breaking down food and absorbing nutrients.

• Ruminants regurgitate the ingested food during digestion, but monogastrics do not.

• Ruminants are foregut fermenters while monogastric herbivores are hindgut fermenters.

• The number of monogastric species is higher than ruminant species.