|
|
Livestock Supplements |
Minerals: What they are and why they
are important?
|
Kay
Dee Feed REPORTS |
Press Release |
| All too often, discussions of dairy nutrition are limited to nutrients
such as energy and protein that have a direct impact on milk production,
notes a North Dakota State University dairy specialist. What about
minerals and why are they important? How much do cows need? What happens
if we don’t provide enough of a particular mineral? Can we provide too
much? While varying mineral levels may not have the immediate impact of a
major shift in energy or protein levels, the long-term effects on animal
health, longevity and growth are significant. |
| "Minerals are inorganic (not of plant or animal origin) elements
required by the body for optimum growth and proper muscle and nerve
function," says J.W. Schroeder, NDSU Extension Service. "Minerals are
essential components of body enzymes, hormones and body cells. Recommended
mineral levels are not constant throughout the life of an animal. In fact,
they vary with changing production, body size, environment and other
dietary factors. In order to calculate a cow’s true mineral need, it is
necessary to know her physiological status by determining if she is
pregnant, how much she is producing, what her maintenance needs are and
how much she is growing." |
| Problems will first be observed in the areas of animal health and
reproduction if mineral levels are not balanced, but the impact will not
be immediate. Many mineral deficiencies are noticed only after a prolonged
period of underfeeding has occurred. Although it may take awhile for
clinical symptoms of a mineral deficiency to appear, sub clinical
deficiencies may have been impairing optimum performance for quite some
time. The primary exception to this rule is mineral toxicity. Extremely
high levels of copper, for example, may actually result in death. |
| "The amount of mineral fed to a cow does not necessarily match the
amount actually used, which complicates our ability to feed specific
mineral levels," Schroeder says. "In fact, mineral absorption is lower
than absorption of most other nutrients. Mineral absorption varies from
one mineral to another and by what form the mineral is. But even when we
have determined how much of the right form of a particular mineral to
feed, our job is not complete, as there are numerous known interactions
between minerals (i.e., high levels of one will decrease utilization of
another) to consider." |
| Known mineral interactions include copper-molybdenum, sulfur-selenium,
calcium-phosphorus, calcium-zinc, calcium-manganese, and
potassium-magnesium. With many minerals, absorption of the mineral
decreases as the amount in the diet increases. It is also important to
note that older animals have more difficulty absorbing minerals. |
| To minimize costs, nutritionists should try to maximize the percent of
minerals provided by typical feedstuffs. However, it is important to
consider that mineral content in concentrates and forages are quite
variable. Frequent forage testing (preferably through a wet chemistry
analysis) is beneficial for economical mineral feeding. Generally,
supplemental trace minerals are supplied through inorganic sources,
typically in the form of sulfates, phosphates, chlorides, carbonates or
oxide forms of the trace mineral. Some inorganic sources of trace minerals
are more available than others (i.e., sulfates are generally more
available than oxides). |
| Organic minerals are often classified as chelates or proteinates and
are bound to amino acids or proteins. "They are usually absorbed in the
intestine by a different mechanism that may increase their bioavailability
and provide a unique function when other minerals are interfering with the
availability of a desired mineral," Schroeder says. "Organic minerals are
generally more expensive, but they may still be advantageous, particularly
as related to immune and reproductive responses. As a rule of thumb, one-
third to one-fifth of trace mineral supplementation should come from
organic mineral sources, depending on the specific mineral desired." |
| Macrominerals are needed in higher amounts and are usually expressed as a
percentage of the ration dry matter. Calcium, phosphorus, magnesium and
sulfur are macrominerals that are important to the dairy cow. |
| Microminerals are needed in smaller amounts and are generally expressed
as parts per million (ppm). Iodine, zinc, iron, copper, molybdenum,
fluorine, cobalt, selenium and chromium are examples. |
| "Minerals are an integral part of any successful herd management
program," Schroeder says. "Often, correcting an imbalance in mineral
levels can solve a nagging problem by improving reproductive performance
or animal health, with very little additional cost. While research
continues to redefine the forms in which minerals are delivered to the
cow, their role in animal performance remains the same." |
| Read More About Minerals |
|
|
|
| SUPPLEMENT FINDER |
|
|
|
 |
| |
|
