The Effects of Altering the Protein Efficiency of Lactating Dairy Cows on the Whole-Farm Nitrogen Efficiency of Dairy Farms.

View the project final report

Commodities

• Animals: bovine
• Animal Products: dairy

Practices

• Animal Production: animal protection and health, manure management
• Crop Production: nutrient management

Average whole-farm N balance for dairies in the West was consistent with other studies in that imported feed was the single largest N input and animal products, milk and meat, were the largest source of output. The most important subsystem was how efficiently feed N was converted to product N. Manure handling should not overshadow herd and crop N efficiencies in attempts to improve N balances. Milk urea nitrogen was not a good predictor of whole-farm nitrogen balance because of the inclusion of nonlactating animals in the summary.

1. Verify the accuracy of MUN analysis for predicting nitrogen (N) and the N (protein) metabolism of lactating cows in independent digestion studies.

2. Determine the potential use of MUN analysis and a recently developed computer worksheet for predicting N losses and whole-farm efficiencies on commercial dairies in UT and ID.

3. Disseminate all results to agricultural scientists and consultants as well as dairy producers.

Sub-objectives of the University of Maryland as they relate to the overall project are:

1) to improve computer worksheets for calculating whole farm balances by adapting them to the Western region and by implementing changes identified by using the worksheets in this region,

2) to assist with evaluation and improvement in MUN analysis based on research conducted at Utah State University, and

3) to disseminate information from this project to farmers via extension publications and the World Wide Web.