Buchneri Inoculants To
Improve Corn Silage Bunk Life
Silage inoculants are bacteria
that are used to manipulate and enhance fermentation. Until recently,
most inoculants have been homofermentative strains of lactic acid
producing bacteria (LAB). The primary benefits of LAB inoculants are
a more efficient fermentation, resulting in improved dry matter recovery
and improved animal performance. The recent introduction of corn silage
inoculants containing heterofermentative strains of Lactobacillus
is quite different because they also produce acetic acid.
This reduces the growth of yeasts and makes the silage more resistant
to spoilage and heating at feed out and improves silage bunk life.
Aerobic Stability Increases Bunk Life
Lactic acid bacteria increase the fermentation rate, causing the
pH to decline faster and lower. By using a LAB inoculant products
of fermentation are shifted, resulting in more lactic acid and less
acetic acid, ethanol and carbon dioxide. However, lactic acid can
easily be metabolized by yeasts and molds in the presence of oxygen.
Conventional LAB inoculants that reduce acetic acid can actually
reduce bunk life, but this is partially offset by the reduced pH,
particularly in haylage. On the other hand, acetic acid can inhibit
the growth of various yeasts that are responsible for heating when
exposed to oxygen.
Research at the USDA Forage Research Center in Wisconsin and at
the University of Delaware has shown that the inoculation of corn
silage with L. buchneri can reduce yeast and mold growth
at feed out. L. buchneri utilize lactic acid to produce acetic
and propionic acids. Stability is improved, with silage temperatures
not increasing as readily upon exposure to air. Simply put, corn
silage stayed fresher longer. To date, research studies have shown
that L. buchneri treated corn silage with higher acetic acid
levels does not reduce feed intake.
Fermentation Losses Versus Aerobic Spoilage
The increased acetic acid and aerobic (exposed to air) stability
comes at the expense of increased fermentation dry matter losses.
However, dry matter losses due to aerobic spoilage of corn silage
are typically much larger than fermentation losses. In situations
where spoilage at feedout is an issue, the use of L. buchneri
inoculant on corn silage may result in less mold and mycotoxins,
improved palatability and intake, and reduced total dry matter losses.
When To Use Buchneri Inoculants
L. buchneri inoculants should be considered in situations
where aerobic stability is a greater risk. Although L. buchneri
inoculants could work similarly with alfalfa and grass haylages,
aerobic stability is more of a problem with silages that contain
large amounts of starch, such as cereal silage and corn silage.
High dry matter corn silages, and bunk, pile or pit silos with large
exposed surfaces usually have greater problems with aerobic stability
and may benefit more from L. buchneri inoculants. The same
may be true for the top loads in either vertical or horizontal silos.
In tower silos, it is usually the bottom of silo that is fed during
the warmer summer temperatures, when there is increased risk of
Another application where L. buchneri inoculants may be
a benefit is in situations where corn silage is expected to be transferred
from one silo to another. L. buchneri inoculants have also
been shown to increase aerobic stability in high moisture corn.
Remember that aerobic stability is also improved by proper silage
management practices, including recommended moisture and chop length,
rapid filling and packing, sealing, face management, removal rate
and feed bunk management.
Commercially Available Products
There are many strains of L. buchneri and they are not all
necessarily equally effective. Commercially available L. buchneri
inoculant products include Pioneer brand 11A44 (strain 202118) and
Biotal Buchneri 40788. Be sure to follow label recommendations.