Effect of hoof characteristics on the propensity of cattle to slip

A Novel Method of Assessing Floor Friction in Cowsheds and Its Association with Cow Health

Simple Summary

The objective of this paper was to test a simple method of measuring the extent of the slipperiness of different types of floors in cow shelters. Excessively slippery floors, which are less abrasive, are known to reduce a cow’s ability to walk, lie down, and get up without slipping and causing injury to herself. A moderate level of friction between the cows’ hooves and the floor is required for cow comfort and prevention of foot disease and injuries. This study developed a rapid method that welfare assessors can use to measure the slipperiness of floors in cowsheds. The data obtained were then validated by comparing them with the various animal-based and resource-based welfare parameters assessed in each shelter. The analyses done in this study show that there is a link between excessively slippery floors and various parameters such as frequency of cleaning the floors, the gradient of floors, wounds on the bodies and joints of the cows, and the presence of dirty hind limbs. All of these ultimately affect the welfare of cows in shelters. These results suggest that this simple measure of floor friction could be useful in cow welfare assessments. Further work on the repeatability of this method is recommended.

Abstract

Measurement of friction of cowshed floors to determine slipperiness potential is important for cow comfort. Existing methods require elaborate equipment and procedures. A quick method for assessment of friction characteristics is proposed. Friction was measured in 54 cattle housing and yard facilities with earth, brick, concrete, and stone floors, and its association with cattle health parameters was investigated through assessment of 30 animals per facility. A 156 g cuboidal wooden block attached to a spring balance was pulled over 3 m, and the coefficient of friction was recorded as the force required to move the block at a constant speed. The coefficient of friction ranged from 0.3 to 0.7 and was lowest for concrete and highest for earth floors. A multivariate analysis found that cows were standing more and could be more easily approached when they were on floors with high friction levels. The proportion of cows with dirty hind limbs declined with increasing friction of the floor, probably reflecting the fact that they felt more confident to stand rather than lie on high friction floors. This simple measure of frictional characteristics of cattle floors offers promise to be included in welfare measures as an indicator of cow welfare.

Determination of coefficient of friction between the equine foot and different ground surfaces: an in vitro study

Slippery surfaces are a continuous concern in equine veterinary practice during both treatment and orthopaedic work-ups, especially when horses have to trot on circles. Sliding of the equine foot on the ground with the potential of injury is prevented if the horizontally acting accelerating or decelerating forces on the foot do not exceed maximal friction. Friction can be calculated and therefore anticipated if the coefficient of friction (μ) between the foot of the horse and the particular ground surface is known. Friction between shod and unshod cadaver equine hooves and different ground surfaces (concrete, tarmac and rubber) was determined by pulling the hooves horizontally in a uniform motion. Horizontal forces (Fh) were measured on a force plate and with a portable digital electronic force meter. The coefficient of friction (μ) was calculated as the quotient between Fh and the gravity force (N) of the object, hence: μ = Fh /N. This study has shown that the coefficient of friction between equine hooves and a specific ground surface can be determined using a portable digital force meter or a force plate. Friction significantly depended not only on the type of surface but also on shoeing of the equine foot. Bare feet showed more friction with the hard surfaces (bricks and tarmac), the shod feet showing more friction with the rubber surfaces. Coefficients of friction could be used to estimate the possibility of injuries occurring in the equine industry during exercise and/or lameness or pre-purchase examinations.

Frictional Forces Required for Unrestrained Locomotion in Dairy Cattle

Most free-stall housing systems in the Netherlands are equipped with slatted or solid concrete floors with manure scrapers. A slipping incident occurs when the required coefficient of friction (RCOF) exceeds the coefficient of friction (COF) at the claw-floor interface. An experiment was conducted to measure ground reaction forces (GRF) of dairy cows (n = 9) performing various locomotory behaviors on a nonslippery rubber-covered concrete floor. The RCOF was determined as the ratio of the horizontal and vertical components of the GRF. It was shown that during straight walking and walking-a-curve, the RCOF reached values up to the COF, whereas for sudden stop-and-start responses, the RCOF reached values beyond the maximum COF that concrete floors can provide. Our results indicate that concrete floors do not provide enough friction to allow natural locomotory behavior and suggest that tractional properties of floors should be main design criteria in the development of better flooring surfaces for cattle.

The effect of shoe material on the kinetics and kinematics of foot slip at impact on concrete

Previous studies on shoeing have demonstrated that shoe material alters the time taken from foot impact to the foot stopping sliding (slip time) and the distance slid. These are assumed to reflect differences in the craniocaudal ground reaction force (GRF) between the shoe and the ground during foot slip. This study tested the hypothesis that the slip time and distance are reflected in the resistance to slippage of the foot after impact. The forefeet of 8 horses were shod in horseshoes constructed of steel, plastic and rubber. Each horse was trotted for 8 placements per forefoot in each shoe type over a concrete topped forceplate and simultaneous kinematic data recorded at 240 Hz. Slip distance and slip time were calculated from the kinematic data and craniocaudal (Fy), and vertical (Fz) GRFs determined during slip the averaged for each shoe type. The slip time and distance were variable between runs in all 3 shoe types, and there was no significant difference between the mean values for the 3 shoe types. Fy reached a value of 0.98 +/- 0.17 N/kg during slip in the plastic shoes which was significantly lower than the rubber shoes, at 1.13 +/- 0.17 N/kg, P = 0.02. The Fy/Fz ratio (a measure of dynamic friction) was significantly lower in the plastic shoes, 0.34 +/- 0.08, compared to the steel shoes, 0.46 +/- 0.04, P = 0.003. This study is being extended to investigate effects of shoe slippage at the end of the stance phase and the energy dissipation during foot slip in the different shoe types. Future investigations should aim to identify the optimum slip characteristics to modulate loading (magnitude and rate) during impact, with the aim of reducing the risk of injury.

The locomotion of dairy cows on floor surfaces with different frictional properties

The locomotion of dairy cows was evaluated on floors with a smooth epoxy resin surface or with a surface-applied bauxite aggregate of mean diameter 0.5, 1.2, or 2.5 mm (coefficients of static friction, mu 0.35, 0.42, 0.49, and 0.74, respectively). Locomotion was recorded as cows walked to receive a food reward. Cows on the floor with least friction walked rapidly (0.85 m/s), with frequent, short steps. At the start of the supporting phase the upper limbs were more vertical. Joint arcs during this phase were reduced. Cows on 0.5-mm aggregate also walked rapidly (0.84 m/s); they had the least vertical limb angles and long steps but held the hoof more vertical, probably to offset any increased slip risk. On floors with larger aggregate, cows decreased speed and step frequency but maintained long steps, keeping their upper forelimbs more vertical to reduce the supporting limb phase. It is concluded that on a low friction floor (mu < 0.4), cows walk quickly with frequent, short steps. As mu increases to 0.5, step length increases and the number of steps decreases to maintain speed at increased friction, producing an optimal coefficient of friction between 0.4 and 0.5. Further increases in mu may increase the hanging limb phase at the expense of the supporting limb phase, to reduce friction, while maintaining a long stride to expedite arrival at the reward.

The locomotion of dairy cows on concrete floors that are dry, wet, or covered with a slurry of excreta

Six dairy cows were trained to individually walk down a concrete aisle for a food reward. Their locomotion was then examined in a switchback experiment as the floor surface of the aisle was changed from dry to wetted concrete or concrete covered by shallow (5 cm) or deep (12.5 cm) slurry from cattle excreta. The static and dynamic frictional coefficients were measured by a tribometer, but did not give a clear indication of the risk of slipping. Cow locomotion was measured over the second half of the aisle, and limb angles recorded as the cow passed a video camera. Wetting the floor did not affect the walking or stepping rate, but it reduced the arc made by the joints of the hindlimb during the supporting phase. Slurry caused the cows to keep their legs more vertical at the end of the support phase, probably to aid lifting the limb out of the slurry. It also caused the cows to place their forelimbs down less vertically at the start of the support phase, probably because of the reduced risk of slip in the slurry. When the floor was covered with either the deep or, to a lesser extent, the shallow slurry, the cows' walking and stepping rates were reduced, and on the floor covered with deep slurry their step length was increased. Therefore slurry reduces the cow's walking speed and alters limb angles during the support phase, producing a different walking pattern from cows on dry or wetted concrete.

Frictional properties of cattle hooves and their conformation after trimming

The conformation of the hooves of nine heifers obtained from an abattoir was measured and their coefficient of static friction (mu) was determined for movement in forward, backward and sideways directions. The hooves were trimmed by the Dutch method and their conformation and p were measured again. Trimming increased mu, and decreased the length of the digit and the angle between it and the floor. The value of mu was considerably greater for movement in a forward or backwards direction than sideways. The relationship between the value of mu for sideways movement and hoof conformation was examined by using 52 lower limbs from a variety of cattle breeds. Although mu was greater for Belgian blue than other cattle breeds, there were no relationships between mu and hoof conformation, including a measure of the roughness of the sole.