The milk urea nitrogen, or MUN, concentration in a bulk tank sample can help dairy farmers monitor their feeding and management programs, says Donna Amaral-Phillips with the University of Kentucky Dairy Extension Team. 

When herd values deviate from expected values, it's a good idea to review your feeding and management program, Amaral-Phillips says.

MUN ultimately reflects what occurs during the digestion of feeds in the rumen, Amaral-Phillips says. The rumen microbes use ammonia, peptides, and fermentable carbohydrates to make microbial protein. Between 60 to 75% of a cow's protein needs can and are met by microbial protein, so this process is very important to the cow for her to produce milk. When inadequate or excessive amounts of certain types of protein, known as rumen degradable protein (RDP) or inadequate amounts of carbohydrates are present in the rumen, the MUN concentration in milk changes. These changes in MUN content can be used to pinpoint problem areas within a feeding and management program.

Click here to read more in the latest issue of Kentucky Dairy Notes.

Source: Kentucky Dairy Notes, February 2012