Reprinted from the May 21, 2008 Issue of Alberta Agriculture's Agri-News

The two most important nutrients in any cattle feeding program, summer grazing or winter feeding programs, are energy and protein. Without these two nutrient requirements being met, any other management practice will be compromised, including the calcium and phosphorus ratio, supplemental feeding of vitamins or minerals - be it inorganic or chelated, or vaccinations to prevent diseases.

"Nutrient use by cows and other animals follows a hierarchy or ranking of importance," says Barry Yaremcio, beef and forage specialist with Alberta Agriculture and Rural Development's Ag-Info Centre, Stettler. "Research done by Dr. Bruce Young, University of Alberta, (1975) found that the first animal function lost when nutrients are deficient is growth. The second function lost is reproduction, and the third is immune function. In many cases, an animal will stop gaining weight or not become pregnant before any symptoms of illness appear. A lack of energy or protein in a ration will appear more rapidly than symptoms of a trace mineral deficiency."

Many producers are willing to put out mineral or protein tubs as supplements, but they are taking this action prior to feed testing their forages and grains. Instead of guessing and spending $100 to $200 for a tub or bags of mineral, producers would be better off spending some of those funds on a feed testing program. This is true even on pasture. A feed test will provide the information to determine where you are starting from and make it possible to then add the nutrients by feeding supplements, vitamins, and minerals that are needed to balance the ration rather than using a shotgun approach. In many situations, producers will save money in the long run.

"Trace minerals are deficient in feeds grown in Alberta," says Yaremcio. "Data from Alberta Agriculture's Soil and Animal (ASANL) Nutrition Lab database provides an insight to levels found in local feeds. The Nutrient Requirements of Beef Cattle (NRC Beef 2000) is considered to be a reliable reference for beef nutrition and provides the 'minimum requirement' for all nutrients."

The left half of the following chart provides nutrient requirement levels that NRC believes is needed for beef cows in early lactation. Four macro minerals and five trace mineral levels are used for the comparison. On the right half of the chart, feed test result values are provided. Requirements are stated as a percent or milligrams per kg of dry feed intake. Maturity and year effects will cause feed test values to change.

Salt and mineral blocks can help provide cattle with the trace minerals that are needed for optimum growth and production. Placing the blocks in areas where the animals are grazing or in areas where excess grass needs to be grazed, improves forage utilization. Placing salt and mineral blocks in watering areas is not recommended as this will only kill out the forages and weeds will establish in these areas.

Cows can consume up to 75 per cent of their salt or salt and mineral product at night, so a salt or mineral station in sleeping areas will improve consumption.

Information provided by Barry Yaremcio 310-3276 (toll-free in Alberta) or 1-866-882-7677; out of province 403-742-7901 or barry.yaremcio@gov.ab.ca.