29 April 2014

5 minute read

Lameness is detrimental to animal welfare and fertility, and it is one of the three main reasons for involuntary culling, according to Swedish animal production expert, Christer Bergsten.

When dairy cows are confined, as in a free stall system, their feet and legs are affected by wear, trauma, and by microorganisms, writes the Swedish University of Animal Sciences expert.

He emphasises that the cow’s ability to rest, stand and walk must be optimized.

Key messages

Invest in management:

• Look after hygiene, management of floors and possible traps for traumatic injuries
• Reduce unnecessary exposure of feet and legs to hard, abrasive and unhygienic floors by excellent cow comfort with one cubicle per cow
• Reduce wait-time for milking
• Provide enough space at the manger and feed for all cows 24 hours every day

Invest in construction:

• Invest in soft resilient flooring with rubber of excellent quality
• Invest in drainage of urine on solid floors by sloping floors with cleansing urine canals
• Preferably invest in rubber, matted, slatted flooring with scrapers, traditional or robotic
• Invest in feed stalls with rubber mats
• Prepare firm and water drainable exits and gateways to pasture

Exposure and Cow Traffic

The comfort of the lying area, such as its space and softness, influence the cow’s lying time. Since the cow rests 40-60 per cent of the day, the other 60-40 per cent of the day is spent standing for different activities such as moving to feed, to milking etc.

Any decrease in lying time will have an adverse effect on feet and threaten claw health, if alley flooring is poor. Another reason for prolonged exposure of the feet could be overstocking.

Overstocking by having two heifers per stall has been shown to increase standing time, lameness and sole horn lesions. Cow traffic means the availability of different resources for the cows.

Well-planned cow traffic should reduce the risk for competitive interactions between cows for milking, feeding, drinking and finding a resting place.

Flooring

Even if the lying area is of outmost importance it cannot compensate for poor flooring, because animals still have to move around to socialize, to feed and to be milked.

The ability to exert each specific activity such as resting, standing and walking must therefore be optimized. This means a soft yielding floor with enough friction to reduce claw over-growth, yet preventing over-wear and avoiding poor hygiene by ensuring as dry and clean floors as possible.

A study that compared six different floorings with different surface and structure showed that locomotion was best and friction highest on rubber floors.

Concrete is the most common base for floors in cubicles and alleys, and the alleys are either slatted or solid and scraped. Concrete has advantages and disadvantages, such as abrasiveness of new concrete and slipperiness of older worn concrete. The disadvantage of slipperiness with aging concrete has to be calculated for when planning a barn.

Grooving the hard concrete is normally better than stamping pattern. If the grooves in the concrete are not satisfactorily sharp, with time the flooring will be less comfortable, compared to a floor in which grooves are cut with sharp edges.

Concrete flooring can be covered with materials such as rubber or mastic asphalt which alter the growth and wear of claw horn.

Mastic asphalt has very good frictional properties but the wear off rate (abrasion) could be too high. The slipperiness of the rubber matting of floors depends on the rubber quality and softness of rubber. If rubber is hard and smooth, it can be as slippery as smooth concrete.

Several studies show that the introduction of softer alleys with rubber surface improves walking comfort of cows and results in less laminitis-related claw diseases. Another study shows that dairy cows had a preference of 80 per cent both for standing and for walking on rubber compared to concrete.

In a recent study by Bergsten, first calving heifers were housed on slatted concrete or slatted rubber mats during their first lactation. The cows on slatted concrete were 3,5 times more likely to be lame.

There is a high risk for lameness, claw and leg lesions impairing behavior and welfare when dairy cows are introduced to a new barn. A study compared the hoof health on cows that were introduced on new concrete vs. new rubber mat flooring, in a cubicle system with scraped alleys.

It showed that rubber alley flooring can prevent and reduce such problems and rapidly pay back the investment. In this study it was 10 times more likely for a cow to become lame on concrete than on rubber floors.

According to Christer Bergsten one dead or euthanized cow less per year will pay an investment of 300 m2 of rubber mats in 10 years. (In Sweden a dead cow is estimated to cost approximately 2 300 EURO or 3 000 USD.)

Hygiene

All types of floors should separate urine to reduce ammonia emission. This is most easily done with slatted flooring where urine is separated instantly.

Most of the manure is drained through the slats depending on the design of the slats, manure consistence, cow traffic and presence of scrapers or not. Urine can also be separated and drained on solid floors if the floors are sloped to a midway parallel canal.

It is contra-preventive for claw health if a ‘wave’ of manure flushes the feet when scraping. The use of feed-stalls can protect the feet from dirt and if it is equipped with rubber it provides soft flooring when feeding.

Feed stalls also allow the cows to avoid any manure ‘wave’. Scrapers are also efficient on slatted flooring and in robot milking systems. Robotic scrapers are becoming more common and they improve claw health and stall hygiene because less dirt is transported in to the stall.

Foot Bathing

Foot bathing can prevent and treat infectious claw diseases but can be difficult to manage. Copper sulphate in different concentrations has been widely used and is the only solution with documented effect besides formalin.

Because of environmental and health concerns with copper and formalin, respectively, alternatives are needed.

The old way of foot bathing has to be developed into easier systems to wash and treat feet. New foot washing systems are under development with promising results. Washing feet automatically is most likely “the” method for the future.

If skin is clean bacteria will starve to death and the possibility for disinfecting substances to act is better than today’s walk through foot baths which are depending on heavy metals or formalin, which are unwanted substances.