Evaluation of milk urea concentration as useful indicator for dairy herd management: A review

Abstract

Protein is an expensive ingredient of dairy cattle feeds. Overfeeding of protein contributes to environmental pollution and higher feed costs. Although, high dietary protein stimulates milk production, increased protein has been found to be detrimental to reproductive performance of the animal. Efficiency of protein feeding is a function of nitrogen supply to the rumen as well the cow. Consequently, a system to monitor protein feeding must account for rumen as well as post ruminal supply and efficiency. Milk Urea Nitrogen (MUN) has potential to be utilized as a non-invasive input to a system to monitor the crude protein status in a dairy herd on a regular basis. The MUN in a dairy herd provides an opportunity to formulate the dietary protein constituency that optimizes nitrogen utilization for milk production and avoids possible negative effects on herd fertility. Milk urea varied by season, month, parity group, stage of lactation and sample type. Researchers should consider controlling for these variables as potential confounders when exploring the relationship between MU and nutritional management or measures of performance such as production or reproduction. © 2011 Academic Journals Inc.