Agricultural production systems are adapting operations to meet the increasing demand for wholesome and affordable food. Attention has focused on the long-term impact on ecosystems of both crop and animal production. With reference to animal agriculture, concerns have been expressed about the concentration of minerals in manure and its subsequent effect on soil mineral content and phytotoxicity.

1. T
he US Environmental Protection
Agency has placed some metals such
as copper (Cu), nickel (Ni) and zinc
(Zn) on their list of priority pollutants,
as they are considered among the most
toxic elements in the environment when
improperly managed. Trace minerals
cannot be degraded through chemical
or biological processes, and therefore
remain in the soil for long periods of time.
The benefits of supplementing copper, zinc and manganese in
animal feed are critical to animal health and wellbeing, as well as
overall production and performance improvements. For example,
pork producers supplement diets with copper for enteric benefits.
A swine study has shown injected copper could result in a 19.8
percent increase in weight gain and 16.9 percent improvement
in feed conversion. These benefits, along with 9.4 percent
improvement in loin muscle weight relative to live body weight,
underscore the role of available copper in grow/finish pigs. An
important trace mineral for red blood cell health, reproduction
and immune function, copper is also a metal co-factor for an
enzyme responsible for collagen development and is critical for
strengthening tendons, bones, skin and intestines.
In addition, without adequate available zinc in poultry diets,
young birds may not receive the maximum protective benefit of
a vaccination program. Zinc deficient birds are more susceptible
to diseases, resulting in increased mortality, poor efficiency
and ultimately, economic loss for the producer. Deficiencies
can lead to structural defects, as well as compromised growth
performance. Because zinc, as well as copper, has low natural
bioavailability and absorption in the animal, it must be
supplemented to realize the animal’s full performance potential.
Many studies have identified both copper and zinc, when
used at elevated levels, can have a significant effect on the
environment through excretion into the manure. Traditionally,
supplemental copper has been offered in inorganic forms as
copper sulfate (CuSO4) or tribasic copper chloride (TBCC).
Depending on the source of minerals fed, as little as 20 percent of
the inorganic copper may actually be utilised by the animal, with
the remaining 80 percent excreted in the manure.
Producers routinely over-supplement inorganic mineral salts,
believing this is the best way to get the maximum benefit of a
mineral program. However, this over supplementation does not
necessarily optimise animal performance, and in fact the majority
of these minerals will be excreted in the faeces. In broilers, for
example, it can be calculated that 75 percent of the dietary zinc
is wasted in this way. Over time, these minerals can accumulate
in the soil and can affect plant growth, crop production and
ecosystem integrity. The over exposure of some minerals to
plants can reduce photosynthesis, brown the root tips, inhibit
growth and ultimately cause death. The microbial population
in the soil is also affected by minerals contamination when
accumulation has occurred.
Environmental
impact of
micronutrients in
livestock feeding
by Jake Piel, Sustainability Manager,
Novus International
Agricultural production systems are adapting
operations to meet the increasing demand for
wholesome and affordable food. Attention has
focused on the long-term impact on ecosystems
of both crop and animal production. With
reference to animal agriculture, concerns have
been expressed about the concentration of
minerals in manure and its subsequent effect on
soil mineral content and phytotoxicity.
50 | November 2015 - Milling and Grain
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2. Mineral pollution of water resources is also a problem in many
world areas. This is typically due to heavy industrialisation and
urbanisation; however, leaching of minerals from the soil into
water reservoirs often occurs, as well as the transport of soil due
to heavy rains and runoff. The aquatic environment is highly
susceptible to the effects of mineral toxicity as these organisms
are in close and constant contact with soluble minerals over an
extended period of time.
Currently, there are limited regulations for mineral pollution
in many areas. In fact, a recent report indicating poor soil
environment conditions has ignited talks in China, so much so
that, “the State will strengthen its regulatory role and set up a
lifelong accountability mechanism for soil contamination; tighten
the supervision and inspection on the performances of heavy
polluters; and strictly control the misuse and abuse of agricultural
inputs during the agricultural production activities.”
In Europe, KRAV standards limit the highest average
applications of copper and zinc over five years of products
applied to the soil including feed, feed minerals and medicines to
500 and 700 g/ha/yr., respectively (KRAV 2006). Much emphasis
has been placed on strategies for reducing the amount of copper
and zinc excreted in this region.
Recently, the maximum permitted levels of trace minerals
supplemented to swine diets are 170 mg/kg DM for the growing
phase and 25 mg/kg DM for the fattening stage (Lopez-Alonso
2012). It is important for both animal producers and legislative
authorities to have proper dialogue to encourage positive
outcomes in terms of animal wellbeing and good environmental
stewardship.
Reducing the mineral load in the surrounding environment is a
component of sustainable agriculture. The single most effective
measure is the reduction in trace mineral levels supplemented
in the feed. Furthermore, this can be done while increasing the
minerals available for metabolic uptake. It is known that mineral
elements bound to an organic ligand are more stable in the
gut, as the cation does not interact with the other antagonistic
components during digestion. As a result, these organic trace
minerals (OTMs) are delivered to the site of absorption, thus
increasing their bioavailability to the tissues.
In 2014, 117 million pigs were produced in the United States.
Potentially, more than 2 million pounds of copper excreted
in the environment could have been avoided with the use of
MINTREX® Cu from Novus. A recommended lifetime loading
limit for copper in soil is 77 pounds of copper per acre. Using this
recommendation, and supplementing with MINTREX Cu, means
that 27,000 fewer acres are required to manage this mineral
load. This is relatively small if we consider that half of the pigs
produced in the world, about 476 million, are in China. If all pig
feed in China was supplemented with MINTREX Cu, as opposed
to inorganic trace minerals, the result is a savings of 982 million
pounds of copper excreted to the environment as waste. Using
the same US copper loading rates, this is equivalent to almost 13
million acres.
As the global population approaches nine billion by 2050,
food production capacities must increase to accommodate the
nutritional needs of more people. Technological advances in
agriculture and livestock production, as well as sustainable
practices, are critical to achieving this goal. The reduction
of environmental pollution by minerals is one area in which
significant improvements can be made through supplementing
healthy diets with a more bioavailable mineral solution.
References available on request
Turnkey
Feed Mill
Systems
www.yemtar.com
600 Evler Mah. Balikesir Asfaltı Sol Taraf Cad.
No:65 BANDIRMA / BALIKESİR / TURKEY
P(+90)266 733 85 50 | F(+90)266 733 85 54
G e a r D r i v e n P e l l e t M i l l
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