Because a cow's stomach includes four different chambers with their own chemical processes and biological functions, the chemical composition of cow dung includes a variety of different substances. These substances include things like microorganisms, products of digestion, secretions from different parts of the digestive tract and the stomach chambers, and water. Of all these different components, the dung is primarily composed of dead organic cells and undigested food.
A cow's stomach and digestive tract are compartmentalized into chambers and intestinal sections that perform a variety of different functions. Some chambers begin the food breakdown process with fermentation and microorganisms, while others absorb water and other minerals. Because of this complex series of steps, each stage in the cow's digestive process adds different chemicals and substances to the chemical makeup of the dung.
The primary components of cow's dung are the metabolic remnants of living tissue and parts of the food that it was unable to digest, like cellulose and lignin. These undigested substances usually come from the cell walls of plant cells that the cow has consumed. Other examples of materials that can be found in the composition of cow's dung include bile salts, mucus, keratinized tissue and calcium salts from fatty acids.