Concrete surfaces – from the extremes of those that are too smooth to those that are over-grooved and abrasive – are creating a massive problem to the feet of dairy cows.
Yet the simple solution of “scabbling” the concrete is only being undertaken on a handful of UK farms – something leading vet Nick Bell from the Royal Veterinary College finds very difficult to explain.
“Why is it something so straightforward to carry out and which can have such a massive impact on cow mobility hasn’t become a standard approach to concrete management on UK dairy farms?” he asks.
With widespread on-farm problems caused by slippery concrete, Dr Bell is urging more dairy producers to use contractors to achieve a scabbled surface on concrete that has become over-smoothed by excessive wear.
How does it work?
Scabbling is the mechanical process of removing a thin layer of concrete, usually achieved by compressed-air powered machinery. A typical scabbling machine uses several heads, each with several carbide or steel tips to “peck” at the concrete and operates by pounding a number of tipped rods down onto the concrete surface in rapid succession. It takes several passes with the machine to achieve the desired depth.
“There’s no reason why farmers need to put cows at risk by failing to address slippery surfaces when scabbling is an easy solution. I agree there is some confusion about the various concrete treatments that are being offered to dairy farmers, but scabbling – rather than the more widely used grooving – needs to become the priority approach to tackling smoothed surfaces in yards and buildings.
“I can count on the fingers of one hand the number of UK farms where scabbling has been implemented and yet in countries like New Zealand it’s the only way of re-surfacing worn out concrete on dairy farms.”
Scabbling in New Zealand
New Zealand vet Neil Chesterton, who visited the UK earlier this year, says scabbling is widespread among milk producers in New Zealand and is the only method he would recommend to treat the surface of slippery concrete.
“Grooving using concrete cutting saws only lasts for about six months. As soon as the sharp edge rounds off the cows slip again. Some groovers say their “new” method is better by making wider grooves – but basically as soon as the sharp edge wears the cows slip from the top of one square to the top of the next. The slipping risk gets worse when the surface and dung becomes dried.”
Mr Chesterton says scabbling done correctly can last for more than 10 years. “Scabbling doesn’t only roughen the concrete, it also nips the top off the stones in the surface and that’s what provides the grip.”
Dr Bell says far too many cows are culled in the UK because of “doing the splits” caused by having to move around on slippery surfaces – even though scabbling could prevent such accidents.
Hidden lameness costs
“But that’s just the tip of the iceberg,” he says. “There are so many hidden issues such as poor cow flow because animals move slowly and cautiously, not to mention lost bulling activity when cows are unhappy to ride during oestrus.
“Just think of the losses that result from failing to see cows bulling because they are reluctant to display true bulling behaviour on a surface they are unhappy to move around on.”
Although smooth surfaces may not be immediately apparent as the cause of cow lameness, Dr Bell believes there is a hidden risk to cows’ feet.
“While smooth surfaces may not have an enormous impact on cow lameness I’ve seen several dairy farms where old, ‘polished’ concrete leads to an overgrowth of the claw. If these cows were walking on a scabbled surface there wouldn’t be that degree of excessive growth because there is an adequate, but not excessive, element of wear being applied by the scabbled surface.”
Although there are contractors able to undertake scabbling work on dairy farms in the UK – as well as a specialist team from France who make trips here – Dr Bell admits that farmers keen to use their surfaces may have to do some homework to locate them. A recommendation from a farmer who has already benefitted from scabbling may be the best option.
Where to scabble
Because of the abrasiveness of a scabbled surface it’s advisable to avoid areas where cows are undertaking sharp turns – such as parlour exits – but any area where cows are walking in straight lines – as well as the collecting yard – are prime targets for scabbling.
Because of the risks of making a surface over-abrasive, farmers are advised to use a professional contractor rather than attempt the job using a hired machine.
Grooving has been widely undertaken as an improvement measure on concrete within dairy units, but while grooving carried out “to the letter” and following DEFRA’s guidelines can provide an acceptable surface, Mr Bell says the grooving he sees on many farms is too severe and is having an adverse effect on mobility and foot health.
“Many farmers are tempted to make the grooves wide and deeper in the incorrect belief the surface will endure for longer. In effect it can be extremely damaging to cows’ feet.”
Case Study – John David, Aberaeron, Cardiganshire, Wales
Lameness isn’t a problem on John David’s farm at Aberaeron in Cardiganshire: “It’s great when I can say to the Farm Assurance people that I don’t have lame cows – and it’s all because of providing cows with a scabbled concrete surface to walk on,” he says.
Concrete that was laid more than 40 years ago has been scabbled twice – once about 20 years ago and again two years ago. The approximate cost of the most recent work was £250 for two areas – 75ft x 20ft and 60ft x 20ft.
“It’s like taking emery paper to the smooth and slippery concrete. The scabbling cuts through the glaze and the shine and provides a roughened surface, but it doesn’t break through the concrete – in fact I don’t think we swept up more than a few bucketfuls of dust from the entire area,” says Mr David who milk 80 Guernsey cows.
The scabbling was undertaken by a local contractor using a hand-held three-headed scabbler.
“It doesn’t damage the concrete, but it’s not a solution for concrete in poor condition,” he stresses. “It needs to have been mixed well when it was laid and be 4in thick.”
Mr David says scabbling has meant cows are no longer slipping or doing the splits and consequently lameness is not a problem.
Scabbling versus grooving