Tackling lameness essential to dairy profits
Lameness in cattle affects production, fertility and longevity adding considerable cost to often fragile farm finances.
Despite this too few producers are picking up the warning signs expressed by affected stock, lameness experts told last weekend’s inaugural National Cattle Mobility Event at Harper Adams College, Shropshire.
Vet Roger Blowey said despite 30 years’ experience with lameness, incidence levels within the UK remained practically unaltered.
Opinion varied over the cause of lameness. In dairy cattle there is a relationship between milk yield and prevalence of lame cattle, he said. “Some think it is down to nutrition, but I’ve yet to see a diet that only affects the hind feet where 80% of lameness occurs and particularly as 80% is found in the lateral claw.”
It requires a more holistic approach. UK research had shown milk yield drops were detected two to four months before lameness was physically seen in milking cattle resulting in 400 litres lost yield, he explained.
Understanding just how much weight a cow puts down each leg highlighted the stress on individual claws, explained National Association of Cattle Foot Trimmers’ Chris Just. “A 460kg cow puts 260kg down the front legs and 200kg down the back. Each rear claw is taking 50kg – two bags of feed – when standing square.
“As soon as she tries to shift weight to alleviate discomfort from a lesion or ulcer in one foot that increases the claw load on the other to 75kg. If she lifts a leg it’s a dramatic 150kg. All that is being carried on a claw just a quarter of the size of a man’s size nine shoe.
According to Swedish lameness specialist Christer Bergsten it’s no surprise to find the UK had the highest lameness incidence at 55% compared to the USA at 35% and France 11%. “In Sweden it is about 1% today. We have 400,000 cows in 7500 herds often in tied stalls and producing 9500kg milk annually.
“In my travels across the world I see greatest lameness in the same breed (black and white). Lameness is not just a management issue, it is a breeding issue. Production traits are easy to select for genetically, but disease resistance is harder,” said Prof Bergsten.
On-farm producers could do more to recognise cows at risk. “Look for the signs. Those with arched backs, standing on the kerb in cubicles, and those at the back of the herd when coming in from grazing or at the back of the holding pen at milking time are candidates.
“If cows spend an excessive amount of time lying they’re in discomfort. In cubicles they cannot swap sides and you get the tell-tale hock lesions. A cow that suffers lameness repeatedly should not be bred (to produce replacements),” suggest Prof Bergsten.
Other practical steps should be taken. Swedish research highlighted risks of lameness fell significantly where cattle had feet trimmed before housing. Also, choice of floor covering made a huge difference. Concrete was abrasive, but became worn over time. Slats are good for hygiene, but not comfort.
“The ideal is rubber coated slats but these are costly (£25-30/sq m) and can make getting muck away through small slots difficult.
“In trials in California cow units laying rubber conveyor matting down cow walkways saw cattle walk in single file along its length. They are voting with there feet as it puts more pressure on the outer claw as a cow would experience at grass,” he said.