Dairy Management
Managing Dairy Cattle Lameness in Wet Conditions
Prolonged exposure to moisture causes the hoof to soften, making bruising, penetration injuries and white-line disease more prevalent. The skin between the toes and around the foot also softens and macerates leaving skin more prone to infections such as footrot.
Why is Lameness Important in Dairy Cows?
Lameness is associated with acute pain and can:
- Decrease the cow’s ability to graze
- Cause loss of milk production
- Lead to lowered reproductive performance
- Increase the chance of a cow being culled
- Cause loss of income, and loss of profits through the additional cost of treatment
The overall cost of each case of lameness was estimated in ‘On Track’ at between $200 and $300 per case (2003), so the costs of a herd outbreak can quickly become substantial.
Increased Risk of Lameness in Dairy Cows in Wet Conditions
The most common causes of lameness in extremely wet conditions or floods are:
1. Cows that stand in water for days at a time, will have their hoof walls and sole softened by the constant contact with moisture. Softened hoof soles are very susceptible to penetrating wounds, stone bruising and excessive abrasion of the sole surface. Cows can’t see the stones if they arehidden in mud and walking them along damaged track surfaces compounds the risks. Penetrating wounds allow bacterial infection to enter the foot and form abscesses.
2. Inter-digital skin, the usually hard skin between the claws, becomes soft, macerates and forms cracks on long exposure to wet conditions. This skin is then prone to injury from any sharp object such as buck-shot gravel or even crop stubble. This allows the footrot organism to gain entry.
Footrot infection should be suspected if the foot is swollen, hot and painful above the hoof and where the cow shows extreme reluctance to place weight on that foot. Washing the mud off the foot may reveal a crack in the inter-digital skin and a foul smell from the dead skin on each side of the crack.
3. Soft hooves are more prone to developing fine cracks along the white line, especially if they a returning on abrasive concrete. The white line is often thicker and softer with many cracks running across it following prolonged wet conditions. Bacteria can enter into theses cracks and lead to theformation of abscesses in the foot.
4. Mud coating the feet and lower legs can conceal many other problems. Wire or debris left in the paddocks from floods can become wrapped around the claws; sticks and stones can become trapped between the claws; cuts and open wounds are more common as the cows cannot see sharp objects in the mud. The only way to find these problems is to thoroughly wash the feet and examine them.
Strategies to Prevent Lameness
1. Patience in Handling Stock
Allow the herd to move slowly and give them as much time as possible to choose where they place their feet. If there are sections of track washed away then allow the cows to work out their preferred alternative route even though this may take longer. Refrain from using honking horns or barking dogs.
Minimise the use of the backing gate in the yard and let cows move into the shed at their own speed. Cows pushed up tight may result in sole injuries and loss of hoof sole as cows pivot on the concrete surface. Soft hooves are easily worn away by twisting and turning on abrasive concrete.
2. Protect Hooves from Rough Surfaces
Damaged tracks can be topped with sawdust, woodchips or limestone as a temporary fix in areas that have deteriorated during wet conditions, particularly in the last 20-30 meters in the lead up to the concrete holding yards. Similarly, areas of concrete that pose a danger to hooves (ie at the entry onto the concrete, cow turning areas) can be covered with carpet or matting in the short term. A foot wash at yard entry can wash sand and small stones from the feet before they reach the concrete.
Longer term the tracks need to be constructed properly with a camber that promotes water to run off the surface and drainage that takes the water away from the foundation material. Trees and hedges shade the track surface and can prevent drying. Keep drains unblocked and scrape away mud and repair damaged surfaces quickly to prevent serious deterioration. Tracks should never be topped with road screenings, rough screed, broken concrete, large river stones or builder’s rubble. If it is comfortable foryou to walk along with bare feet then it should also be OK for the cows.
3. Fence Off High Risk Areas
If flooding and debris have created particularly muddy or rough areas, these should be removed or fenced off to prevent stock from accessing these hazards.
Treatment Strategies for Lameness
Remove any cow showing lameness from the herd, place her in a paddock near the milking shed, and consider once-a-day milking. Once a day milking is covered in more detail in a related sheet ‘Managing milking in wet conditions’. Walking less improves welfare and prevents the injury becoming serious.
Early examination and treatment of lame cows not only improves welfare but also limits the financial losses from a loss of body condition, milk production and the culling of affected cows.
The use of 5% formalin or 5% copper sulphate foot-baths or treated hoofmats may be useful to prevent and treat large outbreaks of footrot and bacterial infections. Footbath chemicals can be dangerous and should be handled with care.
Footbaths should be at least 2.5m long and the raceway through them should allow cows to go through in single file. They should be used once daily. Treated hoofmats can be placed on the way into the dairy to increase the time cows are standing on them. They should be recharged regularly and can be used at every milking.
Biotin and zinc supplements in the diet can be useful to strengthen the hoof in the long term.
When examining lame feet be sure to consider the occupational health and safety aspects of treating lame cows. If you are unsure of the cause of the lameness or the best treatment to be using it is important to discuss the problem with your veterinarian.
Summary
- Prompt and effective treatment of cows that are lame is a win-win situation for both businessperformance and for managing cow welfare.
- Small efforts to rectify lameness problems early will save the larger effort and expenditure of trying to fix the problem later when it has become untreatable.
Further Resources
If you require any professional advice on the treatment of lameness please contact your veterinarian.
Additional valuable information on lameness prevention and treatment can be found in the references listed below.
Irwin R and Malmo J (2003). ‘On-track’ – The treatment and prevention of lameness in dairy cattle
CowTime’s Guidelines and Quick Notes contain information on stockhandling, yard and track design
For further information, please visit:
www.dairyaustralia.com.au/Managing-In-Wet-Conditions Dairy Australia