Broschüre 2004 zum Download (pdf | 1994,28 KB) - H. Wilhelm ...

ROTH-MAIER
And what is done with the penalized milk?
DRIEHUIS
It’s too late for measures, because analysis takes 4
days, then the milk is already in the cheese factory.
ROTH-MAIER
And afterwards? With these farmers, which are
producing this milk, what is done?
DRIEHUIS
If they have this penalty, they will be analysed the
next time again, 2 weeks of 4 weeks later, and the
farmer is kindly asked to do something else, take hygiene
measures or take another silage, or whatever.
But because it costs him a lot of money, he probably
will do so.
JANKNECHT
Ich hätte eine Frage zu den letzten Untersuchungen
auf dem Betrieb. Sie haben gesagt, Sie haben Proben
genommen an der Frontseite des Silos, und es ist ja
bekannt, dass wir mit dem Eintritt des Sauerstoffs die
Reaktionenfolge auslösen. Je weiter wir in das Silo
hineinkommen, umso geringer sind die Probleme.
Sind dort auch Proben im Abstand 1 m, 2 m, 3 m
von der Frontseite gezogen worden? Die Frage zielt
aus pragmatischer Sicht darauf, was der Landwirt machen
kann. »Verdichtung« ist eine Sache, die andere
die angepasste Silogröße auf dem Betrieb.
DRIEHUIS
There are more measures possible, because it’s not
only the consolidation, the compaction, it’s also the
feeding rate, controlling aerobic instability. Another
possibility is the use of special silage additives which
reduce the risk of aerobic instability. But that should not
be the primary measure. The primary measure should
be, make a good silage first. But to answer the first part
of your question, we do not take samples at different
depths of the silage. We just took the material that was
in front, and one hour later was moved to the cows.
KNEIFEL
I should like to come back to the distribution of
the clostridia within the silage package. May be, there
could be some theory behind this and may be this
theory is based on a methodological artefact which
could be caused by the following phenomenon: If
you consider the surface layer of the silage, there
are the clostridia and they react against the oxygen
by the production of spores. If you put the sample
from there, going to the NPN, you have to perform
heat treatment to perform the NPN-Test. During
the treatment you kill the vegetative cells, and only
the spores survive. So you get many positive results
from the spores, but if you go to the inner core of
the silage package you have more or less vegetative
cells, and you are going to kill the vegetative cells by
the NPN-Test. So, this could be the reason to have a
lower count inside than outside, but in fact the total
count, if you compare vegetative cells with the spores,
could be the same.
DRIEHUIS
You are correct, that we analyse spores, we do not
analyse vegetative cells. And, of course, there must
be a step that the spores germinate and grow and,
in the end, sporulate again, but we don’t have any
indication that in the centre of the material there are
a lot of vegetative cells. If it would be, you would
expect some butyric acid, for instance. We do heat
treatment on all samples. That’s the classical way of
measuring spores.
The reason, we think, is, that in the surface layer
the spores, may be due to the oxygen, also probably
due to the increasing pH, start to germinate, grow and
sporulate again, and in the central part you do not
necessarily have high numbers of vegetative cells.
SAUERWEIN
All your approaches to solve the problem in the
cheese were so far focussed on the silage itself.
Would you see any chance to tackle the problem via
in creasing milking hygiene.The numbers Prof. Bauer
was talking about, about 1 g of faecal contamination
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