Added value through feed preservation By Dr. Gerd Diebold, Technical Marketing Manager Organic Acids, EAWA, BASF Animal Nutrition In times of low sales revenues from animal products, farm-produced
odour to visible mould, and possibly toxin formation, is the consequence
feed becomes particularly important, as does its quality.
of microbe multiplication. Once toxins have formed from fungi or bacteria,
Unpredictable weather patterns and heavy rainfall combined
they are almost impossible to eliminate. Spoiled feed can thus lead to
with a more and more effective harvest chain constantly present new
reduced livestock performance. With advanced spoilage of feed, serious
challenges to the harvest of feed such as hay or grain.
illnesses of the animals, occasionally with fatal consequences, cannot
BASF provides solutions that help optimize the nutrient content and quality of harvested feed and improve the hygiene of by-products
be ruled out. Residues of certain mycotoxins such as ochratoxin and aflatoxin in the final products meat and milk are also known.
and farm-produced feed. This is where the known mould-inhibiting effects of the propionic
Advantages of preservation
acid Luprosil® are particularly useful. Depending on the application,
Natural occurrence of propionic acid
the product Amasil® NA, containing formic acid, is also recommended.
The main active ingredient of the BASF preservation agents is propionic
Formic acid is very effective in specifically preventing the growth of
acid, which is a naturally occurring organic acid. Propionic acid is a
bacteria such as E. coli or Salmonella.
building block in the metabolism of animals and plants. For instance,
BASF also features a number of additional products whose ratio of
up to 1.5 litre propionic acid is formed daily by the rumen microbes
formic acid to propionic acid has been adapted to suit a wide variety of
of dairy cows and this represents an important source of energy for
application areas. The products Lupro-Grain and Luprosil NC contain
the ruminant.
®
®
buffered propionic acid. Lupro-Cid® NA and Lupro-Mix® NA contain additional amounts of formic acid as well. Lupro-Grain® and the ‘NC’ and ‘NA’ products are highly effective and significantly more user-friendly than pure acids, since they are less
Natural propionic acid also occurs in silage. It is found in food too. Swiss cheese contains up to 1 per cent propionic acid which is formed during ripening of the cheese. This concentration is sufficient to preserve grain with a moisture content of 26% for a whole year.
corrosive to infrastructure and are not considered hazardous materials under transport regulations.
Inhibitory effect on fungi, yeasts and bacteria Propionic acid shows broad, antimicrobial activity against fungi, yeasts
Importance of feed hygiene
and bacteria, which lasts up to one year at sufficient doses. The number
Feedstuffs such as grain, maize, pulse crops or even compound feed
of fungi, yeasts and bacteria is reduced drastically by preservation.
have a naturally high population of bacteria, fungi and yeasts. Up to
Subsequent further multiplication of the microbes is successfully
6 million bacteria, 40,000 fungal micro-organisms and 50,000 yeasts
suppressed by Luprosil. These two effects, microbe reduction and
are tolerated as an upper limit per gram of grain. With feed, the micro-
prevention of microbe multiplication, are well illustrated, for example,
organisms have an ideal substrate and under certain conditions can
in a preservation test with winter wheat. The preservation performance
multiply very quickly.
of Luprosil is hardly limited by the grain moisture content. However,
If a high water content coincides with the naturally high microbe
the required Luprosil dose increases in line with rising grain moisture
population, explosive propagation of the fungi, yeasts and bacteria
content and longer storage periods. For instance high-moisture maize,
occurs. In turn, the metabolism of these micro-organisms increases the
even with a water content between 40 and 50%, can be protected
moisture content further and also the temperature of the feed, which
against spoilage for a whole year with Luprosil.
can accelerate the spoilage process.
In addition to preservation in storage, it is particularly important
In the case of oats this critical moisture boundary lies at about 14%.
in practical farming that acid treatment allows the production of low-
Other types of grain can only be kept stable under summer temperature
microbe and hygienically safe feed grain, which relieves the burden on
conditions at grain moisture contents below 15%. Pulse crops such as
the immune system of the animals and has a stabilising effect on the
peas and field beans, as well as rapeseed, spoil at moisture contents
digestive system. This promotes feed intake and digestibility.
in excess of 12% water.
Fungi are virtually completely killed off by Luprosil at the time of
We recommend preservation with Luprosil for a grain moisture
harvesting and reproduction of mould fungi during storage is suppressed.
content of 14% upwards for all grain types and for a moisture content
This successfully prevents the formation of mycotoxins from the time
of more than 12% for pulse crops.
of harvest onwards. However, mycotoxins which are formed up to the
However, acid treatment to reduce the microbe population and to
time of harvesting by field fungi (e.g. the fusariotoxins, zearalenone and
improve the hygiene quality is worthwhile even at lower moisture contents
DON = Desoxynivalenol), cannot be eliminated by acid treatment, and
and is particularly recommended for breeding sow and piglet feeding, as
remain in the grain. Thanks to acid preservation, however, it is possible
well as for use in liquid feed. Feed spoilage, which ranges from a musty
to harvest the grain at the optimum ripening time, despite a relatively
Page 40 September/October 2016 Feed Compounder