Using Milk Urea Nitrogen as a Nutritional and Environmental Decision-Making Tool to Improve Dairy Sustainability

Project Overview

Project Type: Research and Education
Funds awarded in 2024: $349,999.00
Projected End Date: 07/31/2027
Grant Recipient: University of Idaho
Region: Western
State: Idaho
Principal Investigator:
Dr. Izabelle Teixeira
University of Idaho
Dr. Mireille Chahine
University of Idaho
Pedram Rezamand
University of Idaho
Dr. Bruce Richards
Utah State University
Amy Skibiel
University of Idaho
Dr. Hernan Tejeda
University of Idaho


  • Animals: bovine


  • Animal Production: feed management

    Proposal abstract:

    Dairy operations face increasing concerns about environmental
    pollution caused by nitrogen excretion from dairy cattle. The
    mitigation of the environmental impact associated with dairy
    farming can be achieved by ensuring that cows receive an
    appropriate amount of protein for efficient milk production. Milk
    urea nitrogen (MUN) is a valuable tool for monitoring dietary
    protein and nitrogen excretion. However, the interpretation of
    MUN values is constrained by its high variability, which is
    attributed to a wide range of factors that are not
    comprehensively elucidated. This proposal aims to refine the use
    of MUN as a decision-making tool to enhance nitrogen utilization
    efficiency in dairy cows and reduce the environmental impact of
    dairy farming. We will collect data over two years from three
    dairy farms in Idaho and one in Utah to determine the
    relationships between MUN and animal characteristics, production,
    and diet composition. Subsequently, we will derive
    computer-assisted mathematical models to relate MUN and animal,
    production, and diet parameters. Our study will also quantify how
    changes in MUN are associated with economic and environmental
    outcomes. To evaluate the impact of environmental factors, such
    as heat stress and wildfire smoke, on MUN variability, controlled
    experiments will be conducted over two years at the University of
    Idaho Dairy Center. Our educational plan includes implementing
    the Pacific Northwest Dairy Nutrition Practices School (PNW-DNPS)
    to educate producers, nutritionists, feeders, mid-herd managers,
    students, and other professionals about the importance of good
    feeding management practices for delivering an effective
    nutrition program. Furthermore, we will disseminate information
    about using MUN as a decision-making tool through traditional
    outreach methods and various media formats, targeting
    professionals involved in dairy nutrition and advising producers.
    To facilitate the practical application of our research, we will
    develop a user-friendly web-based tool called MUNTune, which
    integrates the derived equations to monitor MUN on dairy farms.
    Model adequacy will be evaluated using an independent database
    from published studies. By refining the use of MUN as a
    decision-making tool, dairy farmers can enhance nutrient
    utilization, reduce environmental impact, and promote the
    long-term viability of dairy farming practices. This proposal
    will contribute to the sustainability of the dairy industry by
    improving protein efficiency, achieving cost savings, and
    reducing nitrogen excretion.

    Project objectives from proposal:

    1) Derive MUN equations based on on-farm data and quantify
    economic effects on MUN of varying animal, production, and diet
    characteristics; 2) Evaluate the effect of the environment on the
    variability of MUN in dairy cows; 3) Develop and deliver the
    Pacific Northwest Dairy Nutrition Practices School (PNW-DNPS); 4)
    Disseminate information and educate the public about the use of
    MUN as a decision-making tool to enhance nitrogen efficiency of
    dairy cows; 5) Develop a mobile-friendly web-based tool (MUNTune)
    for producers and nutritionists to help them monitor the diet of
    dairy cows, given their site-specific characteristics.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.