Falling on Concrete Causes “Un-seen” injuries in Cattle
“Falls” on slippery floors are criteria measured during Humane Handling Audits in U.S. and E.U. Slaughterhouses. According to the AMI (American Meat Institute) Guidelines, 1% or fewer falls where the body touches the ground are acceptable, more than 1% is not OK, and 5% or more indicates a severe problem. Severe injuries to the hocks and knees can occur after falling on concrete, and bruises in the loin, back, and shoulders happen often. Hard falls on concrete cause large areas of muscle damage, a significant source of financial loss to the industry. The fear of falling is natural and common in humans and mammals. Fear of falling causes anxiety in cattle and makes quiet low stress handling difficult.
Deeply Grooved Concrete
Non-slip concrete floors are best for cattle, but when cattle fall, they can be easily injured. The finish on concrete should be deep grooved in high traffic areas to prevent slips and falls and rough broom-finished where people walk. However, Do not use deeply grooved concrete on floors cattle stand on every day. A less aggressive groove should be used in holding areas or on the feed apron where cattle stand to eat.
The shape of the groove is essential. V-shaped grooves work better than square grooves and are easier to clean when sediment gets packed in the grooves. The best groove is a 1-1/2-inch wide (38 cm) x 1-1/2-inch deep (38) groove in an 8-inch (203 cm) diamond pattern. Lay the grooves down on a 45-degree angle to the direction of cattle movement. Use smaller 1/2-inch (1.3 cm) grooves for sheep and pigs.
Concrete Grooving Tools
Make the grooves by modifying a concrete bull float by mounting angle iron (1-1/2 in. x 1-1/2 in.) pieces mounted on the float, spaced 8 in. (203) apart. Cut the angle iron pieces longer than the bull float is wide, heat the ends, and shape the points like a canoe. Weld the bolts on the inside of the angle iron canoe. Drill holes in the modified float to mount the angle iron. Shape a second single piece of angle iron and install a rebar handle for finishing grooves along the edges of the fence.
Pouring the Floor
Prepare the site before the concrete. Set all the posts and build the forms. Clear the area inside the concrete forming from all debris and expose the bare earth. Place and compact a sub-base of fill gravel unless the soil is compact and stable.
A 6-inch (15cm) deep concrete slab is recommended. To make a curb, place the forms 6-inches outside of the fence posts. Use a minimum of 3000 psi concrete for a top-quality floor slab. This concrete mix ratio is 1 part cement, three parts sand, and three parts aggregate to produce approximately a 3000 psi concrete mix. The gravel should not contain dirt or clay mixed with the sand. Mixing soil with sand and gravel makes the concrete wear out quickly.
The most common mistake is pouring too much concrete at one time. Pour one half of a standard mixing truck or 4 to 6 yards at a time, maximum. Concrete consistency is essential to make good grooves. The grooves fill in if the concrete is too wet. The grooves are difficult to get deep if the concrete is too dry. The good idea is to practice on a test slab. Make a 10-foot x 10-foot test pad and build concrete forms. Learn when it’s time to pour and how to use the tools before pouring the floor. Concrete sets faster when the weather is hot and slower in cold weather.
Make a single pass over the concrete with the bull float, first on one side of the fence and then the other, forming a diamond pattern. Do not attempt to smooth the concrete at this stage. The grooves will fill in. Any rough edges eventually smooth out after a small number of cattle have walked on it.
Washing the Floor
Curved cattle handling systems built with solid steel sides need a 2-inch gap (maximum) at the bottom of the fence for washout. A more significant gap at the bottom of the fence can cause serious injury if an animal gets a leg under it. The bottom rail should be no lower than 12-inches from the ground on open-sided fences. High-pressure water is helpful for washing concrete. Some people believe the ease of cleaning is more important than providing non-slip floors. I don’t see it this way and stress that cattle are injured when they fall on concrete. Bruises are most evident when cattle fall at the slaughter plant; the bruises are easy to see and must get cut from the carcass. At the ranch or feed yard, the bruises are less evident and sometimes heal before slaughter.
The Cow’s Point of View
Where cattle walk, the floors need to look the same from one end to the other—no drains or other contrasts that look different.
Cattle have slit-shaped pupils and have poor depth perception because their vertical vision is around 60 degrees. Cattle have to look down to see down.People have about 140 degrees of vertical vision and don’t have to look down to see down. Also, as a defense mechanism, cattle hold their head high during handling or when under stress. Because of this, shadows or drains look like a hole or ditch. When cattle are not under pressure when crossing a ditch or gutter, they lower their head to check it out.
Properly grooved floors make the difference between a quality low-stress facility and one where cattle are nervous and more likely to be injured. The concrete is about one-third of the cost of an average ranch handling system. Concrete contractors without experience in deeply grooved concrete floors should have this information and understand the critical aspects of non-slip floors. A job done right requires practice. A small concrete test pad is inexpensive and worthwhile.