Cow comfort: Walking
The quality of floors, in terms of shape, hardness, friction and hygiene is of great importance for the health of cow feet and legs. Large groups that spend a long time in a waiting area, more frequent milking, long feeding time and long walking distances on concrete floors can be contributing factors for excessive wear and overburdening of the hooves.
A quick survey of hoof health in a herd and detection of lameness can be made by observing whether cow’s backs are arched during walking and/or standing. A cow arching her back when walking or standing and showing lameness in her feet, is likely to have a severe foot lesion.
An ideal floor must be hygienic, comfortable to walk on and have an even, slip-resistant surface without being too abrasive. The floors must be simple to construct, durable, easy to manage and maintain. Concrete has long been the most common material for floors in confined animal systems, but a softer and more resilient material like rubber might be a future alternative. The use of modified mastic asphalt seemed very promising, but it is very heat sensitive to apply. This has led to mastic asphalt releasing the stones (which are part of the asphalt) too easily, which results in increasing lameness and hoof problems. In the meantime, management solutions that facilitate cow traffic and reduce excessive involuntary standing and walking on concrete floors must be encouraged.
All walking surfaces should be slip-resistant. This reduces injuries and increases mobility to feed, water and resting areas. It also encourages oestrus activity. If you notice cows walking very slowly or timidly with rear feet spread wide, it could be a sign of poor traction.
All concrete should be grooved to make it less slippery. Before placing cows on freshly poured and grooved concrete, be sure to smooth off rough or sharp edges to prevent hoof injury. On-farm observations of ‘new concrete disease’, when cows are introduced to a new concrete surface, suggest that newly grooved concrete can cause hoof problems. Instances of lameness, related to acidosis and poor feeding management, are often exacerbated when cows are moved from dirt to concrete or from old concrete to newly poured and grooved concrete. Invariably, productivity of the herd suffers under these conditions.
To prevent hoof problems related to new concrete, reduce the abrasiveness of new concrete. Beginning several weeks prior to introducing the cows into the facility, drag a 900 kilogram block of concrete with a tractor over the new and grooved alleys, lanes and holding pens. Some farmers have used street cleaners to remove particles and dust sanded off during this process. This or similar approaches effectively sand off rough edges without reducing the effectiveness of the grooving. An excellent point to consider is that if the floor is uncomfortable for people to walk on in bare feet, the same is probably true for the cow as well.
When allowed a choice, cows often prefer to stand on a rubber surface rather than concrete. Consider installing rubber mats to improve the daily routine of eating, drinking, walking and resting. In barns with worn out concrete, consider installing rubber coverage to prevent hoof problems. Besides the barn, the waiting area and parlour are very common places to put rubber coverage as the cows will be standing there for a while and impacting their hooves. Recent on-farm experience has indicated the usefulness of using dry cows or heifers to condition a new facility prior to introducing the lactating herd. By having these animals in the facility a week or so before the milking herd, it gives the new barn a cow smell and puts some manure in the alleys. This technique recognizes the importance of accommodating normal cow behaviour and facilitating cow comfort to reduce stress when designing the cow’s environment.
To reduce the chance of hoof injuries, dairy cows should be kept in conditions that allow their hooves to stay dry as much as possible. Pieces of claw horn and whole digits from hooves of dairy cows absorb water rapidly when soaked in water, and much of the water is absorbed during the first hour of soaking. As water is absorbed, the hooves become progressively softer. In comparison with water absorption rate, water loss tends to be slower when the hooves are allowed to dry out. Regions of the hooves differ in hardness. Hoof walls are the hardest, the sole is softest. However, all parts of the hoof absorb water and become softer. When cows are forced to stand on damp surfaces, their hooves will rapidly become softer, which increases the chances of hoof injury and lameness.
Way of walking
A healthy cow walking on pasture places the rear foot into the position vacated by the front foot on the same side. On slippery floors or in dark conditions that alter a cow’s confidence, she places her rear foot outside the track of the front foot while altering the stride, step length and walking speed. This altered walking behaviour provides greater stability but places greater stress on the outside claw.
Choices of flooring and lighting influence walking behaviour, foot health and cow movement. Foot placement, length of stride, step and walking speed provide indicators of cow health and the quality of the environment. Cows walking slowly with small steps but not showing lameness are often a sign of poor quality walkways.
Observation of walking patterns provides an opportunity to assess floors for traction and flatness of the surface for the hoof to rest upon. ‘Birdbaths’ in concrete floors are health risks that pool wastes, contaminate feet and tails and allow splashing onto beds, teats or legs.
A good alley has a non-slippery, preferably soft surface for cows to walk on. It also needs to be as dry, clean and have sufficient light for a cow to see where she walks. On top of that, there should be enough space for one cow to pass by another cow, even if this one is eating and therefore likely to be standing in a 90 degree angle to the walking direction.
Barn planning – crossovers
Crossovers or escape alleys should be established on each end of a cubicle section. If the cubicle row consists of more than 20 cubicles, the farmer must establish additional crossovers to achieve a free cow circulation.
Fertility – influence of floor surface
The quality of the floors has a big influence on the visibility of heat detection signs. With a non-slippery surface, cows are much more likely to exhibit the activity signs of oestrus.
The hygiene of barn floors has considerable impact on animal health. Problem floors impact the hoof, the udder and milk quality. The design of floors is therefore very important for long-term, consistently profitable, milk production. The floor is the part of the barn with which the animals are in closest contact.
Manure produces an unfavourable environment for hooves by macerating digital skin and horn tissue. It also provides a growth medium for contagious agents.
Solid and slatted floors
Slatted floors normally stay cleaner than solid floors. However poor drainage of slatted floors can occur when cow traffic is too low or when there is too much litter or food on the floor. Scrapers on top of the slatted floor improve hygiene. The cleanliness of solid floors can be improved by sloping with frequent scraping or flushing. The slope should have a maximum incline of 1.5 degrees, positioned towards the middle part of the alley and longitudinally towards the dung channel. The liquids can drain easily from sloped floors which results in drier surfaces. A disadvantage is that manure will be spread over this dry surface by the manure scraper. This is why some farmers prefer a non-sloped surface in combination with a scraper system. Solid floors have the advantage of being more natural and comfortable for cows to walk on.
In a Swedish study, the prevalence and severity of heel horn erosions associated with interdigital dermatitis, were significantly higher in stalls where cows were wrongly positioned. The moisture content of the sole horn was positively correlated to the severity of heel horn erosions. This agrees with an American study which reported a high association of stall moisture with lameness. To position the cows better, rubber-coated slatted flooring in the rear part of the stall was developed and studied. The incidence of heel horn erosion was significantly lower in cows on the rubber-slatted floor than in the matched control animals, which were on solid floors with rubber mats. Epidemiological studies from France and California reveal that the most significant risk factor for heel horn erosion and papillomatous digital dermatitis respectively, is unhygienic conditions. It is thus clearly documented that a more or less permanently manure contaminated environment predisposes for infectious foot diseases.
Treatment and maintenance
Hoof trimming has two main aims:
- Promoting optimal conditions for hoof conformation and locomotion
- Detecting and treating hoof disorders before more serious problems develop and cause lameness
Frequently the hoof trimmer or veterinarian is called to treat cows only when an acute need for trimming has been detected. By then, many cows will have already decreased production and suffered needlessly. In one research project, half the cows in each of the herds being studied were randomly selected to have hooves trimmed an extra time, four months before the yearly scheduled trimming. When hoof disorders were compared at the spring trimming, the animals with just one trimming had 67 percent more lameness and 57 percent more sole ulcers than those trimmed twice. Acute treatments between trimmings were very rare in the group trimmed twice and sole ulcers detected at the extra trimming had a high recovery rate of 80 percent. The extra trimming did not have a significant preventative effect on infectious diseases.
Functional trimming is recommended but the quality of hoof trimming should be better followed up. Hoof shape and cow posture both change in an attempt to compensate for physiological and environmental challenges. Harsh surfaces disturb the balance between outer and inner digits of the rear feet, resulting in an asymmetry between them which can lead to hoof injuries and lameness. Correct foot trimming and a soft foundation can equalise the weight distribution between the hooves and restore the sole concavity by putting more weight on the hoof wall.
Hoof trimming twice a year is recommended. Keeping cows on rubber coverage does not change the interval for trimming, as the hooves still grow. They need preventive trimming twice a year. The best time for hoof trimming is at the start of the dry period, so the cow can start the new lactation without lameness problems.
Foot baths or foot spraying
Most modern dairy management systems are compromises, so some measures are needed to prevent health problems. Foot baths have long been used and are recommended in animal welfare regulations. However, there are different methods and techniques in their management and few studies (Appendix 3) on what is optimal. Foot baths can be either true baths or semi-permeable foam mats. Foot spraying has become an alternative for traditional foot baths. The aim is to use hoof health products in an efficient manner to clean hooves and prevent hoof diseases.
Very few studies have been made to clarify the advantages for different solutions. Dutch studies (Appendix 4) during the eighties showed formalin diluted to four percent to be efficient for infectious dermatitis, but it is hazardous and is now forbidden in many states and countries. Formalin is also painful if the animal has an open wound. Copper-based solutions are probably the most commonly used bath solutions in the dairy industry worldwide, although environmental issues may lead to restrictions. Copper sulphate is already forbidden in many countries because it is hazardous for people, animals and the environment. However there are some good solutions on the market now which are less hazardous and work well. A recent study showed a significant positive effect on healing dermatitis when a copper-based solution was used. A foot bath with an appropriate solution is a very easy preventive way to decrease lameness in your herd.
Waste management – manure
It is recommended to promptly remove manure from all types of floors to keep the feet, bedding and walkways as clean and dry as possible. Different manure scraper systems are commonly used to remove manure. They can be timer controlled and operate automatically.