Non-protein nitrogen (or NPN) is a term used in animal nutrition to refer collectively to components such as

urea Urea, also known as carbamide, is an organic compound with chemical formula . This amide has two amino groups (–) joined by a carbonyl functional group (–C(=O)–). It is thus the simplest amide of carbamic acid. Urea serves an important r ...

biuret Biuret is a chemical compound with the chemical formula . It is a white solid that is soluble in hot water. A variety of organic derivatives are known. The term "biuret" also describes a family of organic compounds with the chemical formula , where ...

, and

ammonia Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogenous was ...

, which are not proteins but can be converted into proteins by

microbes A microorganism, or microbe,, ''mikros'', "small") and ''organism'' from the el, ὀργανισμός, ''organismós'', "organism"). It is usually written as a single word but is sometimes hyphenated (''micro-organism''), especially in olde ...

in the

ruminant Ruminants (suborder Ruminantia) are ungulate, hoofed herbivorous grazing or browsing mammals that are able to acquire nutrients from plant-based food by Enteric fermentation, fermenting it in a specialized stomach prior to digestion, principally ...

stomach. Due to their lower cost compared to plant and animal

proteins Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...

, their inclusion in a diet can result in economic gain, but at too high levels cause a depression in growth and possible ammonia toxicity, as microbes convert NPN to ammonia first before using that to make protein. NPN can also be used to artificially raise

crude protein Proteins are essential nutrients for the human body. They are one of the building blocks of body tissue and can also serve as a fuel source. As a fuel, proteins provide as much energy density as carbohydrates: 4 kcal (17 kJ) per gram; in cont ...

values, which are measured based on nitrogen content, as protein is about 16% nitrogen and the only major component of most food which contains nitrogen is protein. The source of NPN is typically a chemical feed additive, or sometimes chicken waste and cattle manure.http://jas.fass.org/cgi/reprint/57/Supplement_2/221.pdf

References

Agricultural chemicals Fertilizers Adulteration Food safety Nitrogen Nitrogen cycle {{livestock-stub

See also

References