
Cutting Phosphorus in Dairy Cattle Feed Will
Save Money, Help EnvironmentBy Linda
McGraw July 16, 1999Feeding dairy cows 20 percent less
phosphorus could save U.S. dairy producers $100 million a year and improve
water quality, according to an Agricultural
Research Service dairy scientist in Madison, Wis. Excess phosphorus in
water--runoff from fields--can boost algae and aquatic plant growth in streams
and lakes. Dairy producers have been overfeeding phosphorus to dairy cows.
The National Research Council has
recommended that dairy cows be fed about 3.8 grams of phosphorus per kilogram
of feed dry matter. An average cow eats about 20 kilograms of dry matter per
day. About a year ago, ARS dairy scientist Larry D. Satter conducted a telephone
survey of more than 30 dairy nutritionists, extension specialists, feed
industry representatives and nutrition consultants. He concluded that, in
practice, dairy producers were feeding an average of 4.8 grams of phosphorus
per kilogram of dry matter. Thats 20 percent more than the typical dairy
cow needs. Over the last 20 years, ARS and other research institutions have conducted
13 studies of nearly 800 milk-producing cows eating both high- and
low-phosphorus diets. From these studies, Satter concludes, contrary to common
belief, that cows fed high amounts of phosphorous had no enhanced reproductive
performance compared to animals fed low phosphorus. Satter, based at the U.S. Dairy
Forage Research Center in Madison will present these findings at the 1999
Four-State Applied Nutrition and Management Conference in LaCrosse, Wis.,
August 2-4. Conference attendees include dairy producers and representatives of
the feed industry from Illinois, Iowa, Minnesota, and Wisconsin. California,
Wisconsin, New York, Minnesota and Pennsylvania are among the top dairy
producing states. ARS is the chief scientific research agency for the
U.S. Department of Agriculture. Scientific contact: Larry D. Satter, ARS
U.S. Dairy Forage Research Center, Madison, Wis., phone (608) 264-5353, fax
(608) 264-5147, [email protected]. U.S. Department of Agriculture | |