The need for vitamins and minerals in cattle operations during the winter months
Many cattle operations lean heavily on hay or stockpiled tall fescue as a primary source of nutrition for their livestock in the winter months. These dormant forages contain lower mineral concentrations compared to vegetative, growing forages. Thus, creating a need for producers to offer vitamins and mineral supplements to their cattle.
Clinical Deficiencies
It takes time for nutrient deficiencies to manifest in cattle. An animal that fails to receive the vitamins and minerals it needs is not going to show clinical deficiencies overnight. “If your cow does not get any copper today, they are not going to die. The body stores vitamins and minerals in reserve for times when feeds are lacking,” Eric Bailey, Ph.D., State Extension Beef Nutrition Specialist in Missouri, said.
Additionally, most feeds and dormant forages still contain some minerals. “Feeds rarely have zero concentration of one or more minerals,” Bailey explained. “Even dormant forage usually contains some concentration of mineral. This makes the time horizon of clinical symptoms of deficiency manifestation even longer.”
Broad Mineral
According to Bailey, though dormant forage often lacks lower mineral concentrations than lush forage; there are not substantial deficiencies known to the forage system in Missouri. Therefore, he recommends producers feed a broad supplement that contains several minerals and vitamins.
“I prefer to use mineral supplements that contain at least 20 percent salt, and have copper, selenium, zinc, manganese and vitamin A,” Bailey stated. Other minerals such as calcium, phosphorus, magnesium, potassium and vitamin D are usually included in the broad mineral product, but they are less likely to be deficient.
Feeding Supplements
Cows can be productive while consuming less than the required amounts of mineral for 30 to 60 days, but beef nutrition specialists advise producers not to allow cattle to go much longer than that without some form of supplementation.
Even though dormant forage still has minerals present, the amount of each mineral varies greatly. “It is difficult to say all forages in Missouri are x-percent deficient in this specific mineral during these months of the year,” Bailey said. “Hence, we pursue a strategy of putting a blend of various mineral supplements together in hopes of filling any gaps.”
Consumption Rates
Typically, mineral supplements are fed as loose mineral in bags, or solid form in blocks or lick tubs. The commercial mineral supplements are sold with recommended consumption rates listed on the labels. Many loose minerals are designed to be consumed at a rate of 4 ounces per cow per day.
Following the recommendation of feeding loose mineral at the rate of 4 ounces per cow per day, then a beef cow would ideally consume approximately two 50-pound bags of mineral per year. “When farmers call or email about mineral supplements, I rarely hear of cows eating that amount. It is very often two to three times more than the recommended intake,” Bailey stated.
Beef nutrition specialists recommend if a cow is overconsuming mineral, remove it from her diet until consumption reaches the set target over time. For example, if a cow eats a half a bag a month, do not give it to her for another 30 to 45 days.
