Many producers provide minerals to the cowherd to enhance cow fertility and productivity. But minerals are just as important for calf performance as well. Here's why:

Research indicates a calf receiving trace minerals prior to entering the feedlot tends to wean off heavier and stay healthier once put on feed. "We've found that when calves are put into a stressful situation, such as co-mingling or entering the feedlot, their immune system doesn't work as well if they are deficient in certain trace minerals," says John Maas, an Extension veterinarian with the School of Veterinary Medicine at the University of California – Davis.

Bottomline, deficient cattle are more susceptible to diseases, do not respond normally when vaccinated, and cost more money for treatments, according to Maas.

For example, severe selenium, zinc and copper deficiencies among calves often result in decreased feed intake, reduced efficiency and lower weight gains. A zinc deficiency can also lead to increased foot problems. Moderate deficiencies of these minerals can be harder to recognize but cause similar symptoms. Hence, it is often a deficiency in minerals that may be the underlying cause of poor performance in the feedlot.

Minerals To Watch
So, which minerals are most important for peak calf performance? Unfortunately, there is no exact recipe for mineral supplementation. Maas points out that mineral deficiency varies depending on forage quality, soil factors, region of the country, time of year, and even type of animal.

As an example, plants don’t require several of the trace minerals, such as selenium, for growth, but cattle do. So, unless the soil has some selenium in it that the plant will capture, cattle will likely be deficient in that trace mineral. Moreover, as cattle are bred for better performance—higher reproductive rates, increased weaning weights, growth, carcass characteristics, etc.—their nutritional requirements also increase.

Thus, to determine the mineral needs of your cattle, livestock specialists advise testing forage and water samples, blood samples, or both. Such analysis allows producers to provide minerals cost-effectively and to the best benefit of the cow-calf pair.

When conducting such an analysis, pay close attention to the major minerals – calcium, phosphorus and magnesium – and the trace minerals – copper, zinc, sulfur, manganese, iron and selenium. Here are a few factors to consider:

1) Pay special attention to selenium. Across the U.S., Maas reports that selenium is the most common trace mineral deficiency among cattle.

2) Evaluate phosphorus. Phosphorus content in forages can vary greatly during the year and is generally lower in dried winter forages. Thus, stockers grazing mature, dried forages will likely require a high phosphorus mineral. But keep in mind that calcium and phosphorus supplementations should be considered simultaneously because of their role in bone metabolism.

The recommended calcium-to-phosphorus ratio for ruminants is usually 2:1. With growing calves, this ratio is especially important. Deviating from it can result in abnormal bone growth and a condition among steers known as water-belly. This condition can block normal urine excretion and cause death in steers when left untreated.

3) Consider zinc. Feeding trials have reported that including zinc in the diet may improve carcass characteristics. But if you consider boosting the amount of zinc that is offered, be sure to monitor copper levels, as zinc can tie up the copper available to the animal.

Lastly, recognize that as we become better farmers and soils are continuously cropped and plant yields are increased, trace minerals may become less available or more diluted. If cattle obtain their feed from a single pasture or hay from one specific area, it becomes even more critical to monitor mineral deficiencies. When the site of feed production is deficient in trace minerals, then cattle will be deficient as well since they have no alternate source for nutrition.

Mineral Management
Once you have your mineral program mapped out, there can be one more challenge: Getting calves to eat the mineral, according to Maas. Despite all the benefits minerals provide, cattle don’t typically like the bitter taste of minerals.

"It can be tough to get cattle to eat what they need to eat, especially in an open range or pasture setting," Maas says. He says research has shown it can take up to 120 days to get cattle on a mineral mix.

Therefore it's best to make minerals available to calves early on, especially as the cow’s milk production decreases over the summer and calves move to a grass-based diet. Minerals are critical for calves at this time because forage alone doesn’t provide all of their nutritional needs. And, as calves get closer to weaning, providing them a mineral supplement can help boost their immune system, as well as get them accustomed to being on feed.

Tricks to try to make minerals more palatable include feeding it with salt (which is a mineral cattle will actually seek out), providing minerals in a molasses or pellet mix when economical, and administering oral mineral boluses when severe copper or selenium deficiencies are evident. Including yeast culture or distillers' grains, a co-product of the ethanol process, can also improve the palatability of a mineral mix. By improving the taste and smell of the mineral mixture, calves are more likely to eat it and get the nutritional benefits the minerals provide.

Finally, keep in mind that there is no reason to go to extremes in offering a certain mineral unless there are unusual circumstances. These are called trace minerals because cattle need only small amounts. Too much of a certain trace mineral can be an unnecessary feed expense, and in some cases can be toxic to animals.