CATTLE LAMENESS: WHITE LINE DISEASE

White line disease is a non-infectious claw horn disease of cattle. The white line is the area of the sole of the hoof where the wall horn meets the sole horn. The horn along this junction is prone to damage, particularly from shearing (sideways) forces. Sole thinning as a result of increased wear can also cause the sole to flex more with resultant damage to the white line structure.

The feet may be subjected to shearing forces if cows have to turn tight corners, or change direction suddenly, for example if being herded forcefully or if trying to escape a bully cow.

If the white line becomes damaged it can become impacted with stones and debris. The resulting infection leads to the formation of an abscess and a sudden onset of lameness. Any cow exhibiting a sudden onset of lameness should have the affected foot lifted and examined at the earliest opportunity. The foot should be trimmed using the five-step Dutch method and the area where the white line has been damaged should be carefully explored until the abscess can drain. Anti-inflamatories should be administered and a block should be fitted to the healthy claw. Early treatment promotes faster resolution and minimises the impact the lameness will have on milk production and fertility.

Key areas to focus on to prevent white line disease include:

• Optimising cow flow and ensuring cows are handled quietly. Improving cow flow will reduce pushing, twisting and turning forces on feet. Ensure backing gates are used appropriately.
• Improving cow comfort to improve lying times – this includes cubicle design, lying surface, bedding provision and stocking density. Over stocking results in a greater likelihood of bullying interactions and greater competition for lying space. Cubicle buildings should provide at least 5% more cubicles than cows. Straw yards should provide 1m2 per 1,000 litres of milk, e.g. a 10,000l cow should have 10m2 lying space. The target is for cows to be lying for at least 12 hours per day.
• Reduce standing times. The longer cows stand on concrete the greater the risk of white line damage, sole ulcers, and other claw horn problems. Ideally cows should not stand for more than 1 hour at milking times.
• Improve flooring – repair areas of uneven concrete and use rubber matting in areas of high traffic and at tight turns such as exits from the parlour. Walking surfaces should be non-slip and as clean as possible.
• Manage cow tracks and gateways – avoid stones and manage muddy areas. Consider upgrading tracks with AstroTurf and sweep regularly. Tracks should never be used by machinery.
• Nutrition. Inclusion of biotin in the diet at 20mg/cow/day has been shown to reduce the incidence of WLD by as much as 50%. However, this is a long-term strategy and due to the time taken for new horn growth, improvements may take at least six months to be seen.

For more details on the five-step Dutch foot trimming method:
https://ahdb.org.uk/knowledge-library/trimming-cows-feet-the-five-step-dutch-method