Improving Water Quality and Dairy Production

Posted: 19-Mar-2009; Updated: 08-Apr-2009

Dairy cows eat a ration that maintains their health and a high level of production, with less excess nutrients excreted in their manure. (Photo: Courtesy Kelly O'Neill)

Reducing the nutrient content in livestock rations is an important way to achieve clean water. Nitrogen and phosphorus are essential for aquatic ecosystems, but at excessive levels they throw these ecosystems out of balance. Improving feed efficiency is one of the easiest ways to improve both the environment and farm profitability at the same time.

Precision feeding improves feed efficiency by eliminating excess nutrients while maintaining or improving milk production. Matching nutrients in feed to cows’ production requirements will help to:

Manage feed more efficiently, so that more nutrients are used for milk production and fewer nutrients are wasted. In many cases, milk production will be maintained or improved while reducing feed costs.
Decrease excreted nitrogen and phosphorus in urine and manure by as much as 25 to 60%.

Tom Nauman, a nutritionist at Hoober Feeds of Gordonville, Pennsylvania, has seen it happen. “We have enrolled a number of our customers on a precision feeding program to improve farm profitability while benefiting the environment,” he says. “They've reduced feed costs by anywhere from 5 to 15 cents per cow per day with no negative effects on milk or milk component production.”

Reducing excess dietary phosphorus

Phosphorus is essential for strong bones and a healthy metabolism. Recommendations for phosphorus were once much higher, but several years of research have shown that milk production and reproductive performance don’t improve with higher phosphorus use. Excess phosphorus in the diet is excreted, adding to the challenge of managing manure in areas where soil phosphorus levels are high.

High quality pastures provide an important part of these cows' diet to keep them healthy and producing milk. (Photo: Courtesy Kelly O'Neill)

Herds with dietary phosphorus levels below 0.4% actually had higher production levels and pregnancy rates than those fed more phosphorus in a University of Pennsylvania study of 65 herds. This clearly demonstrates that removing excess dietary phosphorus didn’t cause problems with reproduction and production. It is likely that other management improvements also contributed to the increases in production levels and pregnancy rates.

Protein and improving nitrogen efficiency

Protein is rich in nitrogen, and it’s one of the most expensive components of dairy rations. Inefficient protein use prevents optimum production because the cow must spend metabolic energy to excrete excess nitrogen, rather than using this energy for milk production.
Some steps to improve protein efficiency include:

Use routine forage and grain testing to determine nutrient content.
Use more highly digestible feeds, such as higher quality forages, more finely processed corn or correctly roasted soybeans so that nutrients are used more efficiently.
Work with a feed professional to evaluate opportunities for improvement.

Help available for dairy farmers

Dairy farmers interested in precision feeding should consult their local Natural Resources Conservation Service office. NRCS’s Environmental Quality Incentives Program provides assistance for developing and implementing a feed management plan as a part of a Comprehensive Nutrient Management Plan. In addition, many feed companies employ nutritionists who are listed on the NRCS Technical Registry and who are trained to help producers develop a plan specific to their herds.

Chesapeake Bay Foundation fact sheet on precision feeding

Conservation Incentives thanks Kelly O'Neill for this article. She is an Agricultural Policy Analyst at Chesapeake Bay Foundation, a non-profit organization and CCI partner that works to improve the environmental health of the Bay.