Page 20 - AWA-41-No.1 issue

DAIRY FARMING

Fine-tuning trace mineral nutrition

for more sustainable dairy farming

ustainability on a dairy farm should
Sbe looked at from different angles.
The nutrition angle is an important one
here. Not only which raw materials we
choose, but also the trace mineral source
matters.
There is a clear need to provide trans-
parency around the environmental impact
of milk production. Considerable prog-
ress has already been made across the
industry. However, there is still room for
increasing the transparency around the
environmental impact of dairy production,
applying improved practices, and better
monitoring progress.
In the quest to build ‘the sustainable
dairy cow’ we must consider short (di-
rect)- and longer-term (indirect) actions. endogenous origins. When we look at Zn, lised, the upper and lower boundaries of
While things like prolonging longevity Cu, and Mn, animals have evolved highly regulatory homeostatic mechanisms, and
and reducing replacement rates have a regulated homeostatic mechanisms to what the cow (in different stages) in the
more mid to-longer term effect, supplying prevent both deficiency and toxicity. For end really needs. The use of advanced
dairy cattle with feeds that are more sus- example, when we feed more zinc, the dairy modelling is a great way to predict
tainable directly lowers the environmental absorption of zinc by the animal goes when the supply is either above or below
footprint of the milk they produce. It can down and endogenous secretion goes the lower boundary and can calculate the
be as simple as changing a fat source or up. However, data illustrating these regu- impact of a supplemental feeding strategy.
using certain circular ingredients. The role latory mechanisms for Zn, Cu, and Mn in Over the years, these insights have led to
of trace minerals in sustainability and the ruminants are scarce. In combination with better defined trace mineral recommen-
differences between sources is also in- attempts to mitigate any possibility of defi- dations and nutritional practices in dairy
creasingly recognised and confirmed. ciency, this has resulted in (too) generous cows, leading to immediate economic and
supplementation of these trace metals in environmental benefits.
Trace minerals – zinc (Zn), manganese modern dairy production systems.
(Mn), Selenium (Se), copper (Cu) and iron Different trace mineral sources, dif-
(Fe) – have a key role in maintaining long- But more insights are gained to better ferent outcomes
term productivity in dairy cows. While fine tune trace mineral nutrition and to After determining the correct level of
supplementing too little can reduce health prevent over or under supplementation. supplementation, it is also very important
and productivity, we must be careful not At DairyNutriVision, research by Daniel to consider the quality and source of the
to overfeed certain trace minerals, as this et al (2023) was shared, addressing that trace mineral used. This is required given
can be toxic for the animal, but also lead to we should not neglect the role of volun- that the mode of action, stability, and bio-
higher amounts of unused trace minerals tary dry matter intake. The study showed availability can vary between the various
in the faces and urine, hence negatively that dry matter intake can vary a lot from trace mineral sources such as (oxides,
affecting the environment (e.g. soil and late lactation through the subsequent sulphates, organics and hydroxy). Re-
water quality). Feeding too little of a trace mid-lactation. When dry matter intake search has shown that the source chosen
mineral can reduce health, reproduction is high, combined with current Zn, Mn, can make a big difference – especially in a
and productivity. and Cu supplementation practices, it can vulnerable group such as transition cows.
Understanding regulatory homeostat- lead to exceeding regulatory homeostatic Transition cows go through a significant
ic mechanisms mechanisms resulting in potential body number of metabolic changes. Next to a
accumulation of certain trace minerals. drop in Ca blood serum levels, we also
Trace mineral nutrition is an art and The study also proved the resilience of see a drop in vitamin E, vitamin A and zinc
many things are affecting when and how the homeostatic system when faced with levels in the blood at calving and onset of
much of a specific trace mineral should a temporary low dietary supply of trace lactation.
be supplied. The homeostatic process in metals, which should be acknowledged
the gut of the animal is the backbone here when making recommendations on trace At DairyNutriVision, a recent transition
and mainly regulated by 2 key processes: metal feeding. cow study was presented which com-
1), the secretion of bile, and mucosa into pared sulphates and Selko® IntelliBond®
the gastrointestinal tract from endogenous The work done by Daniel et al and others hydroxy trace minerals (Zn, Cu and Mn),
sources via the pancreas and 2) regulated all help to get a better understanding how fed at the same levels pre- and post-par-
absorption of minerals from dietary and the minerals are absorbed and metabo- tum. The study showed that Selko® Intel-
18 Vol. 41 No. 1