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AUTUMN 2013 ISSUE
LIVESTOCK MATTERS
14
MAST I T I S FEATURE
An environmental challenge turns contagious
Veterinary surgeon
Ben Pedley
XLVets practice
Willows Farm Animal
Veterinary Practice
Their vet, Ben Pedley from The Willows Vet
Group in Northwich, was called in to help
them establish the root cause and get the
matter under control.
Ben said: ‘Immediately after my visit, I rang
the milk procurement manager at the dairy
and explained that we were aware there
was a problem and we were doing
something about it. In such situations,
I always do this. It reassures milk buyers,
who are usually keen to co-operate.’
Ben identified the main culprit as
Streptococcus uberis. He explains: ‘This
is often classified as an environmental
pathogen. However, once an udder has
become infected, it then becomes a
contagious mastitis problem, and the
infection can spread from cow to cow in
the milking parlour.’
Changes to the milking routine were needed,
and chronic high cell count cows were
identified with a view to being culled.
Ben identified three priorities - the first was to
get the bulk milk cell count down as quickly
as possible to protect the milk cheque.
This was a balancing act, as Richard
explains: ‘In a herd of 90 milking cows,
culling a few animals has a significant
impact on our milk volume. So we identified
the problem cows from our milk recordings,
and took the approach of temporarily
dumping it.’
Then Jenny used a testing kit to monitor cell
count levels in the cows, and once they
dropped, their milk went back into the tank.
Ben’s second priority was to treat the cows
that were ‘worth it’. He explains: ‘Research
has shown that the success rate of treating a
chronically infected cow if she is in her fourth
lactation or more, is less than 5%.’
Richard Brooks
Farmer, Hill Top Farm
Ben Pedley
Willows Farm Animal
Veterinary Practice
Last summer, the wet weather over-challenged the mastitis defences for Jenny
and Richard Brooks of Hill Top Farm near Winsford in Cheshire. Cell counts
rose to over 300,000 cells/ml, and aroused concern from their milk buyer.
Parlour routine
Ben explains: ‘The third priority was
to prevent the remaining cows from
getting worse. Changes to the parlour
were needed.’
The major change was to introduce
the flushing of units with peracetic acid
in-between cows. A commonly used
option is to dump the whole cluster in
a bucket of peracetic acid, but on
Ben’s advice the Brooks immediately
contacted their dairy engineers who
installed four droplines in the parlour
with a jetter specifically made to
tolerate the acid. This provides fresh
solution ‘on-tap’ in the pit.
Now, after each cow is milked, clusters
are flushed with peracetic acid and
those milking the cows rinse their
gloved-hands with the jets too.
Ben adds: ‘Wearing gloves when
milking is essential; hands harbour
bacteria, whereas gloves stay cleaner
more easily and can be washed with
disinfectant between cows.’
The high cell count cows have been
tail-taped and are milked last into a
dump bucket.
Ben adds: ‘It can take up to a month for
cell counts to drop even when a cow has
been treated successfully. Richard and
Jen acted very promptly once we’d
established the best way of resolving the
situation, and soon had the droplines
installed in order to reduce cross-infection.’
By December, the cell counts were
under control, at around 100,000
cells/ml.
WILLOWS
FARM ANIMAL
VETERINARY PRACTICE
Ben Pedley, Richard and Jenny Brooks
Dropline with specialist sprayer
Showing peracetic acid sprayer