Feces

Encyclopedia : F : FE : FEC : Feces

This biological article about feces refers to animals in general. For feces derived from the human body, see human feces.

Rabbit feces are usually 8-10 mm in diameter, and dry to the touch.

Feces, faeces, or fæces (see spelling differences) is waste product from an animal's digestive tract expelled through the anus (or cloaca) during defecation. In humans, defecation may occur (depending on the individual and the circumstances) from once every two or three days to many times a day. Hardening of the feces may cause prolonged interruption in the routine and is called constipation.The word faeces is the plural of the Latin word fæx meaning "dregs". There is no singular form in the English language [link].

The distinctive odor of feces is due to bacterial action. Bacteria produce compounds such as indole, skatole, and thiols (sulfur containing compounds), as well as the inorganic gas hydrogen sulfide. These are the same compounds that are responsible for the odor of flatulence. Consumption of foods with spices may result in the spices being undigested and adding to the odor of feces. Certain commercial products exist that can reduce the odor of feces.

The feces of animals is often used as fertilizer; see manure.

Some animal feces are used as a fuel source, especially for cooking.

Contents

1 In science
2 Related terminology
3 Fecal contamination
4 Human feces
5 See also
6 External links and references

In science

For scientists, feces can provide insight to an animal's diet and life. By carefully analyzing the consistency and odors of the feces, the scientist can understand the contents that comprise the scat. Then, a careful analysis can be conducted which reveals the creature's eating habits.

Feces can be used to determine more than just diet in animals. DNA from sloughed off intestinal cells and metabolites from various hormones can be used to identify genetic differences and stress respectively.

Coprophagia is the practice of eating feces. This is unusual, but some herbivores with a high-fibre/low-protein diet (such as rabbits) eat their own feces as a normal part of metabolism. Plant matter the animal consumes is digested in two passes, with the product of the first pass being re-ingested directly from the anus. After the material is re-digested, the indigestible waste that remains is excreted and left alone.

Fossilized feces are known as coprolites, and form an important class of objects studied in the field of paleontology. Fossilized feces is most commonly found in the form of dinosaur droppings.

Related terminology

Scatology is the study of feces. Informally, the words "excrement", "turds", "crap", and "crud", poop and poopie have become synonymous with feces. The word shit is a vulgar term for feces in English.

Coprophilia, also known as fecophilia, is a sexual attraction to fecal matter. Coprophobia, also known as fecophobia, is a strong fear of feces or human excrement in general.

Fecal contamination

Fecal bacteria at 10,000x magnification

A quick test for fecal contamination of water sources or soil is a check for the presence of E. coli bacteria performed with the help of MacConkey agar plates or Petri dishes. E. coli bacteria uniquely develop red colonies at temperature of approximately 43 °C (110 °F) overnight.

While nearly all strains of E. coli are harmless, their presence is indicative of fecal contamination, and hence a high possibility of other, more dangerous organisms.

Human feces

View: [a picture of human feces]

Human fecal matter varies significantly in appearance, depending on diet and health. Normally it is semisolid, with a mucus coating. Its brown colouration comes from a combination of bile and dead red blood cells. In newborn babies, fecal matter is initially yellow/green after the meconium. This colouration comes from the presence of bile alone. In time, as the body starts expelling excess dead red blood cells, it acquires its familiar brown appearance, unless the baby is breast feeding, in which case it remains soft, pale yellowish, and not-unpleasantly scented until the baby begins to eat significant amounts of other food. Throughout the life of an ordinary human, one may experience many types of feces. A "green" and sometimes "clay-like" appearance to the feces is a result in a lack of blood cells expelled. Bile overload is very rare, and not a health threat. Problems as simple as serious diarrhea can cause blood in one's stool, turning it black. Food may sometimes make an appearance in the feces. Common undigested foods found in human feces are seeds, nuts, corn, and beans, mainly because of their high fiber content.

External links and references

[A FAQ site on poop]
[Short but detailed biological explanation of why feces are brown]
[Liver biochemistry]
History of Shit by Dominique Laporte. ISBN 0262621606
[MedFriendly's Article on Feces]