Maybe it was the full lecture theatre. Maybe the review by Becky Whay of the levels of pain experienced by cattle had primed the response.
More likely it was the picture of the hoof knife embedded in the foot to the hilt that began the sequence of events and the example of coring to maintain drainage, the binder twine to prevent healing, the tubes to allow cleansing and the electric drill bit passing through the claw.
Certainly, when the picture of the amputated foot, hanging before the audience like the Sunday joint before roasting, appeared on the screen there was a huge intake of breath and a dull thud as the first delegate fainted, followed in short measure by a second.
Chris Watson, of the Wood Veterinary Group, halted his talk and looked a little bemused as first one delegate and then the other recovered and left for a cup of sweet tea. The slide remained on screen throughout until the likely cause was identified and the screen moved on, together with the talk.
Something for everyone
The inaugural Cattle Lameness Conference, at the School of Veterinary Medicine at the University of Nottingham, was a well-attended, wellmanaged and successful event. Some 170 delegates registered from a mix of veterinary surgeons, commercial interests, academics and technical organisations. There was something for everyone from the papers and the impressive line-up of posters.
Two veterinary practices, Lambert, Leonard and May from Whitchurch and Synergy Farm Health from Crewkerne presented their projects along with three posters from the Netherlands, two from the Bristol Animal Welfare and Behaviour Group and a combined study with a University of Nottingham team, who also summarised their experiences with mobility.
Writtle College has studied lameness in zero grazed herds and SAC, Edinburgh, lameness factors in organic and non organic herds. But it was the use of novel social marketing techniques in the management of cattle lameness that carried off the best poster shield, applied by the team at Bristol.
Laura Green of the University of Warwick raised some very important questions about lameness and provided some of the answers. Drawing also on studies in sheep, it was noted that although a ewe was “barely lame” for three days, she suffered a drop in body condition, had fewer lambs and the lambs took longer to mature. Cows are lame for much longer and when they are treated their yield rises. Some cows have been shown to be lame for a year.
There are lots of cases of lameness with lots of causes of lameness. Seasonal effects are greater than months after calving. Wet feet lead to a softer hoof and walking on concrete shows a higher incidence of white line disease. Slurry accumulates in the grooves on concrete, providing a surface that is slippery and a problem as cows turn. Laura indicated a personal view that she “really, really does not like concrete”.
Cows have lesions but they may not limp. One of those important questions was “Can cows be detected well before they are seen lame?” Furthermore, “Do low lameness incidence herds detect and treat earlier or do they genuinely have less damage or infection?”
The Treponema species is being studied, in great depth, by Stuart Carter and a team at Liverpool. Worldwide the organism has been difficult to isolate but ways have been developed and their role in bovine digital dermatitis (BDD) is being studied. Some of the information presented has been very recently collated and the work is ongoing.
Three phylogroups
Three quarters of the infections found in BDD foot lesions were made up of three phylogroups and a new species, Treponema pedis, has been identified. Hair follicles and sebaceous glands were found to harbour the organisms and these routes are considered to be the likely entry points for infection. No other locations within the farm environment have shown significant reservoirs of infection. The highest susceptibility is to penicillin and erythromycin.
BDD was first identified in the UK in 1987 and Contagious Ovine Digital Dermatitis in 1997. All countries with dairy cattle report the disease and it spreads between cows, between farms and between species. There is no immunity protection as a result of natural infection, no single effective treatment and no effective vaccine.
In cattle it is a disease of the rear foot. Transmission is from foot to foot with a brief survival period in slurry. The spirochaetes found in lesions are not found on normal skin. Treponemes associated with BDD are not found in the environment but non BDD associated forms are being identified from farm samples.
The indications are that some cows are more susceptible to BDD than others. New work has shown that bacteriophages carry treponemes and the question is raised whether other bugs can also be involved with disease transfer. As well as BDD the organisms have been found in samples from clinical cases of toe necrosis.
Genome sequencing is considered to be a major resource for data mining to determine the pathogenic mechanisms involved in BDD/CODD and provide molecular targets for therapeutic intervention and vaccine development. A trial is on-going with an antimicrobial and the target is elimination of BDD from a dairy farm.
The Faculty of Veterinary Science at Liverpool is continuing to research the role of spirochaetes found in digital dermatitis and other foot lesions in cattle and sheep. Their work has advanced sufficiently that they are now in a position to develop a vaccine. Commercial companies with an interest are invited to contact scarter@liv.ac.uk.
Becky Whay of the University of Bristol is in no doubt that animals do suffer pain and that “they also benefit greatly from receiving the best treatment that we can offer them”.
The effective management of pain requires recognition of lameness, rapid and effective treatment, sympathetic care with limited walking and not having to compete for food together with an environment where the cow can rest comfortably.
The quicker and more complete the recovery, the greater the likelihood of avoiding long-term complications and chronic pain. Analgesia will interrupt or modulate the pain experienced by cattle, promote recovery and reduce the risk of prolonged suffering together with production losses.
“Managing pain will not mask the problem” and “pain is not an instrument for keeping the animal still” were two memorable points. The aim of a lameness improvement programme is to detect lesions, not just lameness. It has to be recognised that sometimes lesions develop after lameness has been observed.
Statistics on prevalence
Jon Huxley, of the University of Nottingham, in his introduction before chairing the session, provided information on the UK prevalence of lameness (0 to 74% of the herd), incidence (of up to 60 cases per 100 cows per year), causes (sole ulceration, white line disease, digital dermatitis, local sole bruising, foul in the foot, interdigital hyperplasia, foreign body penetration, heel horn erosion, heel abscess) with a figure of over £170 for the cost of an average case. Milk yield losses, infertility, weight loss and involuntary culling were all identified. Chris Brown from ASDA Stores Ltd identified that the public require reassurance about welfare, rather than information. The market place requires that lameness and other diseases are managed well and that improvements are made at all levels of dairy cow performance. The carbon footprint of cows is a significant consideration and 500 milk providers to ASDA are being assessed. The top producing herds have a lower carbon footprint and the bottom 25% the highest.
Chris Watson pointed out that the clinician needs to assess, before proceeding with surgery, whether the farmer has the time and education to provide aftercare following treatment.
His talk was full of valuable practical observations, such as backloading of the collecting yard prior to milking maintains the herd social order whereas side loading means that cows of a lower standing are pushed to the back and stand for long periods. Footbaths in parallel offer a better cow flow. The lameness incidence of a herd is three times the lameness score at housing.
Horn necrosis is an emerging condition and Chris advocates a consensus from vets, farmers and technicians on the causes and effective treatments. A step by step guide to investigating lameness is in the proceedings. For future talks to a mixed audience, in order to prevent delegate removal, he may consider it worthwhile headlining that the surgical procedures presented are carried out under anaesthetic.
- Copies of the proceedings of the Cattle Lameness Conference 2009 are available from barbara.hepworth @nottingham.ac.uk or see www.cattlelameness.org.uk.
