THE 2014 Cattle Lameness
Conference, held in Worcester last
month, drew some 80 researchers,
veterinary surgeons and company
specialists. Nick Bell, who
introduced the speakers with
enlightening cartoons, pointed
out that since the last conference
there had
been over 500
peer-reviewed
papers
published.
The growing
evidence-base
was applauded
but by the end
of the day the
overall impression was that there is still
very much more to be unravelled about
issues to do with the bovine hoof.
Sole ulcers
Professor Karl Nuss (University of
Zurich) gave an in-depth review of
the development of sole ulcers and
associated pain. Sole ulcers are painful
when pressure is applied but they do
not always result in lameness. Cows are
able to hide their pain and gait is not
always affected but as a risk for culling,
sole ulcer is considered to be a major
factor.
Utilising videos of cows walking
on a moving treadmill, the normal
weight-bearing attitude of the foot was
demonstrated. The images showed the
twisting and placement of the claws of
the hoof.
It was shown that the greatest
pressure was when the hoof has rst
contact, then lower pressure when the
leg is upright with increased pressure as
the cow moves forward.
These points of pressure explain
how damage to the hoof occurs. The
lateral claw touches the ground first
and the heel, in both the fore and hind
limbs, impacts first.
Comparisons with elk indicate that
paired toes of the bovine foot differ in length and there is a natural genetic
disposition to claws of different
lengths. This difference has not been
shown to result in an increase in sole
ulcers. The mechanical impact that is
transferred from the pelvis directly to
the longer lateral digit in the hind limb
may play a role in the pathogenesis of sole ulcer. Further studies are ongoing.
Observations of claws from cows
leaving pasture and after the cows are housed show a rapid change in the
contour and shape of claws. On hard
ground there is “an overwhelming
predisposition of the lateral claw of
the pelvic limb to overload and develop
a sole ulcer”.
Prof. Nuss said that mechanical
factors rather than systemic
inflammatory factors are the main
cause of sole ulcers.
In discussion he indicated that the
detection of early sole ulcers is best
carried out when the cow is standing
as cows can mask the pain when they
walk. Monitoring the standing cow is
expected to be suitable for automated
detection.
Claw lesion treatment
Margit Groenevelt (University of
Bristol) introduced the ndings of a
combined study involving veterinary
and social science to advance effective
claw lesion treatment.
Her colleague Sue Horseman had
carried out farmer interviews and
assessments. Four dairy herds were
involved and the cows scored for
lameness every two weeks. Cows
were matched for parity and stage of lactation and randomly
allocated to a treatment and
control group.
As a cow showed score
two in the treated group
she was treated using the
Dutch five-step method
within 48 hours.
Control cows were
treated as the farmer saw t. Sole haemorrhage and
digital dermatitis were the
most prevalent conditions.
Recovery rates at two weeks after treatment were 78% for the
treated cows and 21% for the controls.
It was discussed that the poor
results from farmer self-treatment
explains why farmers get demoralised
by lameness treatments as they see
little success for their efforts. The
motivation to identify and treat lame
cows is limited. It was commented that
“never getting cows lame is probably
the best cure”.
Telephone interviews with 84
farmers and face-to-face discussions
with 12 of them investigated farmer
attitudes to detection and treatment
of lame cows. The majority of the
farmers were con dent in their ability
to detect lame cows and half of them
expected to treat lameness within 48
hours.
Different
understanding
The term “lameness” was reserved
by farmers for “severely lame” and
therefore the low detection levels
recorded by other workers may be
correlated more with alternative
language than low detection ability.
An understanding of “treatment” also
differs.
Hoof trimming and placing a cow
on straw may or may not be considered
as treatment. Understanding
a farmer’s point of view
towards lameness is
important if improvements
are to be achieved.
Hettie Thomas
(University of Nottingham)
described a treatment study
for newly lame cows in one
claw. The nal analysis of
the results will be published
later.
The “control” was a five-stage therapeutic foot
trim which would provide a
resolution in about 67% of
cases. Adding a hoof block
improved matters further.
Hoof trimming with
a NSAID increased the
success rate to around
three quarters of cases
and the best outcome was
from trim, hoof block plus
NSAID.
In terms of herds rather than
cows, early treatment resulted in no
severely lame cows with the overall
incidence of cases falling. It is clearly
important to have accurate assessments
of the effectiveness of treatment
programmes.
Although a lameness incidence of
20% is achievable, there is a discussion
around what that really means and
whether such figures are acceptable.
Clearly, 0% category three cows is a
clear achievement at the herd level.
Role of treponemes
Following the development of
antibody-based technology, treponemes
have been isolated, identified and their
role in digital dermatitis examined.
Stuart Carter (University of Liverpool)
explained that three treponeme
phylotypes were shown to be present
together in almost all bovine digital
dermatitis (BDD) lesions but were not
detected on normal cattle foot skin.
Investigations have also shown that
the main, and probably only, infection
site is the BDD lesion. Slurry samples
have proved to be negative.
The same organisms are responsible
for DD in goats and sheep. Lesions
in cattle have typically been recorded
between the heel bulbs but lesions are now seen on the coronary band at the
front of the hoof. The treponemes
penetrate the skin through the hair
follicles, form a lesion which is then
colonised by secondary bacteria which
leads to a full-blown incidence of
digital dermatitis.
Antibiotics only attack the secondary
infection. It is believed that the lower
incidence of BDD with cows at grass
is because of the reduced risk from
secondary infection.
Treponemes have been detected
within bacteriophages and this may
provide a means of transfer between
cows.
Prevention has to be the best
approach and work is ongoing to
identify suitable vaccine candidates.
With BDD, cows generate a non
protective antibody response which is
maintained during clinical disease and
any vaccine will need to overcome this.
Additionally, there may be
opportunities with genetics as BDD
has a host-specific susceptibility. The
future for BDD management is seen
as a mixture of vaccines, good farm
practice and effective treatment.
Niamh O’Connell
(Queens University
Belfast) has looked
into practical
solutions on farm
to the problem of
digital dermatitis.
The time spent
standing in slurry
has been linked to
BDD incidence but
this may be due to
an increase in skin
permeability.
Some cows
persistently suffer
from BDD and
others do not
and this may be linked to different
behaviour of individuals within a
group regarding standing time and
slurry immersion.
Foot-bathing is commonly carried
out on farm but there are wide
differences between the products used
and the management of baths. Parlour
washings and hypochlorite have been
shown to have no beneficial effect but
are commonly used.
The environmental concerns
regarding the disposal of a 5%
solution of copper sulphate indicate
unacceptable usage but this has been
found to be the most effective for
disease control.
Lower concentrations are not
effective but many farmers surveyed
do not know the concentration of the
copper sulphate being used. There is
a need for clear, practical advice to
farmers.
Practitioner’s view
The impact of lameness from a practitioner’s point of view was highlighted by Jim Willshire (Endell
Veterinary Group).
Clinical lameness decreases lactation
yield but the timing of the lameness
influences the effect. The pain of
lameness increases lying down time
and reduces feeding, leading to an
energy imbalance with an increase in
metabolic disorders.
Stating that thin cows get lame and
that lame cows get thin, he said that
once thin a cow is more likely to get
lame. The impact of reduced mobility
on udder health is a concern and poor
foot health may lead to more clinical
mastitis.
Foot lesions have been shown to
increase the calving to conception
interval by up to 40 days. Cows visited
every two weeks that are lame at both
visits before AI have shown a 49%
drop in conception rate. The effects on
fertility are not straightforward.
Lameness leads to an increase
in culling, both for direct lack of
mobility and also concurrent disease.
The results of a study into the effect
of lameness on conception, from an 18-month study of 836 cows, are due for publication.
Steering group
In 2013 the Dairy Cattle Mobility Steering Group was set up. This involves all aspects of cattle lameness with representation encompassing the technical and the practical.
Jo Speed (DairyCo) described the background to the establishment of the group and the aims. Basically it appears that information will be gathered and communicated with activities and recommendations brought to the attention of the industry.
Achievable, affordable and effective measures to minimise lameness and maximise mobility are being targeted to eradicate severe lameness.
Posters
Seven poster presentations were judged by the delegates and the best poster awarded to a combined team from the RVC, Bristol and Oxford on “Quantifying transitions between different levels of mobility score in dairy cows”. With fortnightly mobility scoring, the majority of cows will be detected as MS2 before progressing to MS3.
The conference was organised by the RVC, The Dairy Group and Nottingham University. For the proceedings, visit the website www.cattlelamenessconference.org.uk.
