Formation process:
Food is digested in the stomach, mainly through various digestive enzymes. The colon does not produce enzymes, only bacteria can digest them. There are many kinds of bacteria in the colon, including Escherichia coli 70%, anaerobic bacteria 20%, streptococcus, Proteus, staphylococcus, lactobacillus, spores and yeast.
There are few protozoa and spirochetes. The important function of intestinal bacteria is to produce substances needed by physiology. For example, vitamin K, vitamin B 1, B2, vitamin H, vitamin B 12, B6, tretinoin, folic acid, racemic pantothenic acid, etc. can be synthesized in the intestine in the absence of vitamins in food. It can also produce indole, fecal odorant and hydrogen sulfide, which makes feces stink.
Extended data:
The formation of feces has no important relationship with food, and there is no significant difference between fasting and normal feeding animals, but the amount of feces is reduced. The composition of feces is the same: it contains indigestible cellulose, connective tissue, upper digestive tract secretions, such as mucus, bile pigment, mucin, digestive juice, digestive tract mucosal fragments, epithelial cells and bacteria.
If you don't eat vegetables, the composition of coarse grain manure is often the same, that is, 65% moisture and 35% solid. The solid part of bacteria can reach up to 50%, but most of them are dead when they are discharged.
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