• Introduction

Thin sole is the result of excessive wear. Diagnosis is based on soles that give under finger pressure (<7 mm) or pain when tested with hoof testers in zone 5. Cows tend to take short, cautious steps and may even show cramp-like reactions.

Thin sole is easily underdiagnosed and often masked by secondary lesions, such as toe ulcers, sole ulcers, or white line disease. Therefore, detection rates above 1% should raise a red flag.

It has traditionally been associated with extensive systems, but its frequency is increasing on large farms, especially those with three milkings per day, long walking distances, sand bedding, new housing facilities, and particularly during the summer season.

• Factors

It results from the combination of four factors:

• Softened hooves: due to mud, poor drainage, water/slurry accumulation, or flushing systems, the hoof tends to absorb water and become softer. Poor hoof horn quality can also contribute to this. Within the same herd, hooves affected by thin sole have a higher moisture content. 
• Abrasive flooring: either from fresh concrete or newly grooved concrete. Also from sand bedding. 
• Excessive standing time. 
• Walking along long alleys, three milkings per day, and crowd gates that move cows too quickly.

Why is it more prevalent in summer? Possibly because animals spend more hours standing, crowding in the same wet areas, and sprinkler systems used to reduce heat stress can also be an important factor.

• Control

Rubber flooring in transit areas and the holding area (only needed in the front half) is the first option. On farms with abundant dry manure/compost available, the cow alleys could be bedded with it (see photo).

Increase the frequency of manure scrapers to keep alleys dry.

Formalin/copper sulfate footbaths may help by hardening the hoof, although there are no published studies on this.

Minimize walking and standing time on hard surfaces. This is difficult in practice, as it has other implications, but some solutions could include smaller milking groups or switching from three to two milkings per day during summer. If the problems are associated with first-lactation cows or early lactation, we would recommend separating them into a lower-density group to minimize social hierarchy pressure, which forces them to spend more hours standing.

Supplementation to ensure good hoof horn quality.

Review how cows are pushed towards milking and apply low-stress handling as much as possible. In very long cow alleys leading to the milking parlour, using a double alley system is highly recommended, one for entry and one for exit.

If the problem comes from “fresh” concrete, scrape the floor with the tractor bucket.

If the problem comes from sand, review the type of sand. Sand with very large grains causes more wear, so consider using finer sand or calcium carbonate.

• Treatment

House affected animals in comfortable pens, such as bedded-pack barns with warm or cold bedding, close to the milking parlour. Some authors even recommend milking acutely affected animals only once a day to minimize walking time.

Hard blocks should be used on all lame animals on the farm, whether or not they have thin sole, such as oak wood blocks or Easy Bloc. Never use softwood blocks, the standard ones, as they wear down quickly.

For animals with thin sole in several hooves, we would recommend using soft polyurethane blocks, such as blue TP Blocks.

Anti-inflammatory treatment is highly indicated to relieve pain.

References:

Thin Sole in Cattle, 2015 Petrovski 

Moisture Content, Thickness, and Lesions of Sole Horn Associated with Thin Soles in Dairy Cattle. 2004 S. R. van Amstel,