All animals commonly referred to as buffalo are ruminants. This classification is based on the specialized digestive system they share with animals like cattle, sheep, and goats. These large herbivores consume high-fiber plant matter like grass and forage. They rely on a unique biological mechanism—the fermentation of food in a complex, multi-chambered stomach—to extract necessary nutrients and thrive on diets other mammals cannot efficiently digest.
What Defines a Ruminant
A ruminant is characterized by a digestive system featuring a single stomach divided into four distinct compartments: the rumen, the reticulum, the omasum, and the abomasum. This arrangement allows for foregut fermentation, a process where food is broken down by microorganisms before reaching the true stomach. The rumen, the largest compartment, acts as a massive fermentation vat, hosting a dense, symbiotic population of bacteria, protozoa, and fungi.
When a buffalo first consumes tough plant material, it chews it only minimally and swallows it quickly for storage in the rumen and reticulum, which together are sometimes called the reticulorumen. Later, when the animal is resting, this partially-digested material, called cud, is regurgitated back to the mouth for thorough rechewing. This behavior, known as rumination, mechanically reduces the particle size of the forage, which dramatically increases the surface area for microbial action.
The microorganisms in the rumen produce the enzyme cellulase, which vertebrates do not produce, enabling the breakdown of cellulose, the primary component of plant cell walls. This microbial activity converts the complex carbohydrates into volatile fatty acids (VFAs), such as acetate, propionate, and butyrate, which are then absorbed through the rumen wall and serve as the animal’s main energy source. The last chamber, the abomasum, functions as the true stomach, secreting acid and enzymes to digest the microbes themselves, providing the buffalo with its primary source of protein and B vitamins.
Types of Buffalo and Their Classification
The term “buffalo” can be confusing because it applies to several large bovids across different genera. However, all of these animals belong to the family Bovidae and the suborder Ruminantia, confirming their biological classification as ruminants. The three main groups often called buffalo are the African Buffalo (Syncerus caffer), the Water Buffalo (Bubalus bubalis), and the American Bison (Bison bison).
The African Buffalo (sub-Saharan Africa) and the Water Buffalo (native to Asia) are considered the “true” buffalo, belonging to the genera Syncerus and Bubalus, respectively. Although the American Bison is scientifically distinct, it is commonly referred to as the American buffalo. Despite these differences in genus, all three are members of the tribe Bovini and share the characteristic four-chambered stomach that defines a ruminant.
The Ruminant Process in Buffalo
The buffalo’s specialized digestive process is a direct adaptation to its herbivorous diet, which is largely composed of high-cellulose grasses and forages. The vast capacity of the rumen allows the animal to rapidly ingest large quantities of low-quality, fibrous feed, a necessary adaptation for grazers that spend significant time in open environments where predators may be present. This fast initial consumption is followed by the more secure, leisurely process of rumination later.
Water buffalo, in particular, show a digestive efficiency that allows them to utilize coarser, lower-protein feeds better than domestic cattle. Their digestive anatomy features a larger rumen relative to body size and a potentially slower rate of food passage. This extended retention time maximizes the microbial fermentation of tough plant fibers, allowing the buffalo to extract a higher percentage of available nutrients from its food. The resulting volatile fatty acids fuel the animal’s metabolism.