During the winter, cows have short walking distances between the cubicles and the milking parlour and a short forage for silage, hard feed and water. Standing in slurry contributes to a softening of the soles. The weather warms and the cows are forced out onto rain-washed and muddy tracks. Small stones work into fissures and soft soles. If it is not removed, that stone can remain for the whole summer.
It is not surprising, therefore, that lameness increases after turnout and muddy brick-strewn gateways result in an even greater increase in lame cows than tracks.
Dr Nick Bell at Bristol University gets quite animated when talking about the mobility of cows. The hands come forward to mimic the difficulties of a cow wanting to place her rear feet where the front ones were.
It is similar to the story of the man trying to describe a spiral staircase: it is very difficult with hands in the pockets. There is a whole team of mobility enthusiasts that form the Healthy Feet Project Team and this winter has seen a major advance in interest. Veterinary practices, farmer groups, commercial companies, milk retailers and milk buyers have all requested workshops, meetings and indepth discussions. The emphasis is not on lameness but on cow mobility. There is no pride in having hobbling cows and the idea is a reality that cows can have pain-free movement to the field and the milking parlour and can get up and down in the cubicles without difficulty.
A mobility scoring enthusiast is John Reader at Kingsfisher Veterinary Practice. There will be technical papers produced from the work in Somerset but an early preview highlights a reduction month on month in grade 2 and 3 mobility cows on a 900-cow dairy.
Historically, lameness on this farm was due to sole ulcers or white line disease rather than digital dermatitis. The system that is working is a weekly viewing of all the cows by an enthusiastic tractor driver who detects any limping cows.
The farm management has an “immediate reaction” to lame cows and these animals are brought to the attention of the practice paraprofessional foot trimmer at the weekly visit. The vet sees any animal that requires further attention, or does not respond in one to two weeks. Foot bathing takes place every two days throughout the year.
What is important is that this is a herd that is virtually zero grazed with an expected lower level of mobility. The measurement of success with the mobility scoring generates genuine on-farm enthusiasm for high production standards.
One of the aspects sometimes overlooked with lameness is that it can get worse. More hobbling cows in a herd. Increasingly, the ability to have a mobility score clarifies the day to day situation.
Cows with full mobility and painfree movement score 0. As mobility decreases, the score moves through 1 to 2. These are the cows that will benefit from early treatment. The limping stage 3 cows can be diagnostically misleading and decisions have to be made as to the viability of retaining the cow in the herd.
Economic factors, including stage of pregnancy, will be relevant so decisions are not simply clinical but the whole thrust is to reduce the score 3 and score 2 cows.
Following a whole herd mobility scoring, on one day, an action list of score 2 cows are presented to have their claws trimmed by a foot trimmer. The competency of the trimming is paramount and the outcome is seen by the ability of the cow to track up.
If the cow places her feet correctly then the risk from stone penetration is reduced. A cow with poor mobility, therefore, has an increased risk and trimmers recognise that lame cows pick up more stones.
If the depth of the sole is 8mm, then a small piece of planings of around 5mm is getting fairly close to the quick and grit on a concrete surface leads to bruising. Once the stones are removed, the cow self resolves, so regular attention, particularly after turnout, saves trouble later on.
There is no set intervention level for the limping score 2 cows that are able to keep up with the herd. High protein and energy fed herds would be expected to have more cows with poor mobility due to greater claw overgrowth.
A dairy herd that is housed in the winter and turned out to grass in the warmer weather might average 15% of cows with score 2 and 5 to 10% with score 3. Although these levels are not acceptable, many farmers get used to having lame cows and need to see a clear direction for improvement.
Foot bathing is important. The various options do not soften the hoof and there is no negative aspect to foot bathing apart from management of the chemical, but there is debate whether formalin hardens the hoof. It is not difficult to see that there will be many variations between high yielding and low yielding cows within a herd, the dry cows and the heifers, let alone the variations between farms.
In-depth discussions are raised within farming groups. For veterinary surgeons, the introduction of mobility scoring provides a means of engagement and communication but it is the sharing of good practice between farmers that energises the search for further improvement.
The official term is “social marketing strategy” which identifies the barriers, benefits and incentives with actions that lead to improved productivity and an increasing pride in the performance of the herd. Farmers can have a sense of isolation, which causes negative attitudes, whereas exchanges of ideas within a group allow all the members to consider ideas that will benefit their situation.
If cows are unable to walk properly, then they are considered less likely to feed correctly and yield and general performance falls away. Measuring that cows are moving well is more empowering than counting problem cows.
To review the procedures that increase mobility, go to www.cattlelameness.org.uk. Contact details for the Bristol team are on the website and various activities and courses are available.
- The Cattle Lameness Conference at Nottingham will be reviewed next month.