October 28, 2004

Phosphorous Level Awareness in Beef Cattle May Be Cost-saving

Checking phosphorus levels in beef cattle can be cost saving as well as beneficial to the environment, according to recent research conducted at Iowa State University.

Beef producers have a common practice of having phosphorus (P) supplements available for their cattle at all times. However, supplementary phosphorus is not always necessary. Too much phosphorus in a cow's diet can lead to excess phosphorous excretion in fecal matter, which can be harmful to the environment.

Knowledge of phosphorus levels in cattle can help beef producers know when supplementary phosphorous is necessary. The information can also help producers financially, because costly supplementary phosphorus will not be necessary if there is sufficient phosphorous in the forage they are feeding their cattle.

The research conducted at ISU found that cattle fed on younger forages generally had higher phosphorous levels than those fed on more mature forages. This indicates that cattle fed on younger forages are less likely to require supplementary phosphorus, although variations may still occur.

"The only reliable way to know for sure is to test phosphorus levels in your cattle," said Jim Russell, professor of animal science at ISU.

In the future, new federal regulations may govern how much manure-phosphorus may be land-applied by beef producers. Those regulations are not in place yet, though, and their potential extent is not certain, says Angie Rieck-Hinz, an ISU Extension specialist.

"These new rules won't ban the use of phosphorus," Rieck-Hinz said. "Right now the important things for beef producers are to have current soil tests to all areas they apply manure to, and to assess any conservation practices they have so that they can know their phosphorus index rating."

The phosphorus index rating will be used by the future federal regulations to determine how much phosphorus may be applied.