What is MUN?
Most milk tests report milk urea nitrogen (MUN) levels, and these values can provide significant insight into how dairy cows are using ration protein. MUN is a natural occurrence in cows, and is caused by protein consumption. When cows ingest protein, it is either broken down in the rumen to become available to rumen microbes or escapes to be an available supply of protein and amino acids to the cow for milk production.
Excess ammonia from the breakdown of protein from either source is converted to urea in the liver, where it enters the blood and is removed by the kidneys. The concentration of urea in blood is very similar to urea in milk, so measurements from milk provide a convenient, non-invasive tool for evaluating the protein status of the dairy herd.Read More