Page 7 - Livestock Matters - Autumn 2014

Basic HTML Version

DISPLACED ABOMASUM
Preventing DAs
‘The two biggest risk periods for a DA are
at turnout - because of the change in diet -
and in the first eight weeks of calving,’
explains Sotirios.
‘Immediately after calving, cows will have a
poorer appetite as they recover from giving
birth. And over the following days, the cow
will be in a state of negative energy balance
as she produces more milk than she can
consume energy to support.
‘A prolonged lack of energy can lead the
cow to enter a state of ketosis in which she
will mobilise her body fat to supply the
glucose she lacks. Ketones are produced as
a side-product of the process and these in turn
will reduce the mobility of the digestive tract.
The result: rumen ‘stasis’ occurs and upsets the
flow of digestive fluids. This in turn leads to
the production of more gas.
‘This makes nutrition and feeding in the
transition period key to preventing LDAs.
The milking cow diet needs to be introduced
slowly into the non-milking cow.
‘Another factor is the cow herself: those with
a large abdominal cavity are more
predisposed to the phenomenon, e.g. those
which have carried a large calf, twins, or
breeds which are of a large build,
particularly of deep abdomen.’
A - abomasum in early stages of displacement
B - further displacement, but may not be
diagnosed by sloshing or pinging
C - full displacement, detectable by sloshing
and pinging
Left displaced abomasum
(LDA)
On-farm diagnosis
‘In around 10% of cases, the displacement
of the abomasum is self-correcting,’
explains Sotirios, ‘But farmers shouldn’t
wait, the sooner it’s resolved the better.
‘It’s possible to make some diagnosis
on-farm before calling the vet out, using
two techniques.
‘The conventional approach is to flick with
finger and thumb between the ribs where
the gassy abomasum would have risen to,
and listen for a ‘ping’. It’s useful to have
a stethoscope to do this.
‘Another technique is ‘ballottement’ or more
colloquially, sloshing. This involves pushing
a fist in on the cow’s lower flank - if a
sloshing sound is heard then this indicates
there’s a lot of gas.
‘These techniques can help identify if
the abomasum has moved, but if the
displacement is only in the early stages
then it’s hard to tell and the cow’s
behaviour - her apparent lack of appetite
- is the main indicator.’
Treatment options
There are several veterinary procedures
to remedy DAs. The most common is to
perform a laparotomy in which an incision
(approximately 30cm long) is made into
the abdominal space. A very small
puncture can then be made in the
abomasum to release the gas, and the
organ can be tied back into position.
For the past four years, Sotirios has
been using a new technique in which the
operation is performed using endoscopy,
or ‘key-hole surgery’. It requires only two
small incisions of around 1cm diameter
each to be made. One is the ‘optical
portal’ for the endoscope with its camera
on the end, whilst the other is the ‘working
portal’ into which a hollow cannula is
placed which has a trocar inside to create
the puncture. After the gas is released,
the abomasum is secured back into
position, using a clever set-up of needles
and suturing via the working portal.
Sotirios explains: ‘The small size of the two
portals means they don’t require stitching
up after surgery as they will just close up
naturally. This technique is unobtrusive and
there’s minimal bacterial risk. In most cases,
antibiotics aren’t needed and there’s no
milk withhold period to observe. So
although the operation takes longer than
the ‘toggle method’ and costs more to
do, cow recovery is better, and there’s less
milk lost from the bulk tank.’
‘Using the endoscope I can fully visualise
the situation inside the abdominal cavity.
So it can be used for exploratory purposes
and has proven useful in spotting hidden
problems such as ulcers, or perforated guts,
and even some reproductive problems.
Farmer Phil Langley ‘pings’ a suspected LDA case
AUTUMN 2014 ISSUE
LIVESTOCK MATTERS
6
Sotirios in action with endoscope
Abomasum
Abomasum
Abomasum