What is Non-Protein Nitrogen (NPN)?

Guaranteed that if you handle animal feed on a regular basis you will have seen the letters NPN on the packaging. NPN stands for Non-Protein Nitrogen, so what do you need to know about it?

Where does NPN come from?

Feed-grade urea is most commonly used as a source of NPN, but other sources are also available. Ammonium sulphate, ammonium chloride and mono-ammonium phosphate are among other sourecs of NPN. Molatek, uses only feed-grade urea.

Why is NPN included in animal feed?

Non-ruminants like humans, pigs and poultry can only utilise amino acids from natural protein sources like soya bean oilcake and cottonseed oilcake. On the other hand, ruminants like cattle, sheep and goats can utilise non-protein nitrogen sources thanks to ruminal microbes. These are microbes like protozoa and bacteria found in the rumen of the animal that can use NPN to synthesise protein. This is fortunate for the animal because it means that a portion of their diet doesn’t have to come from a natural protein source – their rumen microbes make it for them.

NPN is included in feed because it is more economical than feeding natural protein. NPN has been added to ruminal feeds for years and is not harmful to the animal as long as it is carefully managed.

Why is there a warning on the label?

Careful management of NPN is essential to ensure that urea toxicity does not occur. When too much urea is eaten by a ruminant, ammonia is produced by the rumen microbes and results in hyperammonemia, also known as urea poisoning, if absorbed.

Always be sure to follow the guidelines according to the feed manufacturer’s feeding recommendations and be sure to store fertilisers and NPN containing feeds safely away from ruminants.