Tag: biology

The rumen is the largest chamber of the ruminant stomach and contains a complex ecosystem of microorganisms that ferment cellulose.

The rumen acts as a fermentation vat where symbiotic bacteria and protozoa break down cellulose into volatile fatty acids.

Bacterial action, which is essential for the digestion of cellulose, occurs primarily in the rumen.

Ruminants are animals that possess a specialized stomach to digest plant-based food by initially eating it and then regurgitating the semi-digested food (the cud) to chew it again.

Ptyalin (salivary amylase) functions in an alkaline or neutral environment. When it reaches the stomach, the highly acidic environment created by HCl denatures the enzyme, rendering it inactive.

Cellulose is broken down to short chain fatty acids in ruminants ,during cellulose fermentation by anaerobic bacteria.

Ruminants include cattle, sheep, goats, buffalo. These animals all have a digestive system that is uniquely different from our own. Instead of one compartment to the stomach, they have four. Of the four compartments, the rumen is the largest section and the main digestive center

Vertebrates lack the ability to hydrolyse the beta glycosidic bond of plant cellulose due to the lack of the enzyme cellulase. Thus, ruminants must completely depend on the microbial flora, present in the rumen or hindgut, to digest cellulose. Digestion of food in the rumen is primarily carried out by the rumen microflora. Since, the environment inside a rumen is anaerobic, most of these microbial species are obligate or facultative anaerobes that can decompose complex plant material, such as cellulose, hemicellulose, starch, and proteins. As bacteria conduct fermentation in the rumen, they consume approximately 10% of the carbon, 60% of the phosphorus, and 80% of the nitrogen that the ruminant ingests. To reclaim these nutrients, the ruminant then digests the bacteria in the abomasum. The enzyme lysozyme has adapted to facilitate digestion of bacteria in the ruminant abomasum. Pancreatic ribonuclease also degrades bacterial RNA in the ruminant small intestine as a source of nitrogen. 

• Rumination is also called second chewing. 
  
• Ruminant stomach: The stomach of a ruminant is divided into four chambers – the rumen, reticulum, omasum and abomasum. 
• The process of digestion is as follows: The food is chewed and swallowed quickly and passed into the first stomach called Rumen. The microorganisms help in breaking down the food. Digestive juices of the rumen partially digest the food. The partially digested food in the rumen is called cud. Hence, The partially digested food in the stomach of ruminants is called cud.