Design of Chutes, Ramps, and Races for Cattle, Pigs, and Sheep
by Dr. Temple Grandin
Meat&Poultry, October 2005, pg. 52
I have received drawings of livestock handling facilities from many processing plants around the world. Many companies ask me to check their designs to see if I can point out any design problems before they are constructed. Some have been really great and could be built as drawn. However, others contained serious design mistakes. These oversights would cause animals to refuse to enter the chute, fall down, pile up or jam.
One of the most critical parts of the handling system is the junction between the crowd pen and the single file chute. The correct design will enable animals to move smoothly from a group into a single file, while the wrong design will cause the animals to either refuse to enter or the animals to jam up the entryway.
Modern, curved-chute systems with round crowd pens will work better than straight chutes, but they must be laid out correctly. Here are four tips on how to avoid some common mistakes:
- Never dead end the entrance of the single-file chute. Animals have to be able to see a place to go. They will not enter if the entrance looks like a wall. The junction between a crowd pen and the single-file chute is one of the most critical points of the system. An animal standing at the single-file chute entrance must be able to see at least three body lengths up the single-file chute before it turns. That will be about 20 feet (6m) for cattle and 12 feet (4m) for pigs and sheep. Animals will move easily through tight bends after they have entered the first section near the entrance.
- Correct crown pen angle at the single-file chute entrance. For cattle and sheep, one side must be on a 30 degree angle and the other side should be straight. This recommendation applies to both circular and crowd pens and straight ones. For pigs, the junction between the single file and the crowd pen should be abrupt. A very gradual transition or a crowd pen that narrows gradually causes jamming. I received two sets of drawings this year that contained this very serious mistake.
- The crowd pen and staging area must be level. Crowd pens, staging areas and holding pens built on ramps will cause animals to fall down and pile up. Groups of animals held stationary on a ramp will move back and pile on the back gate. A slight drainage slope will not cause a problem. If the system has a ramp, it should be in the single-file chute part of the system. Newer facilities for pigs should contain no ramps and be level. Cattle and sheep will stand quietly in single file on a ramp.
- Design single-file chutes to the correct length. A common mistake is to make the single-file chute too short. If the chute is too short handlers have to hurry and push animals too hard to keep up. The chute should be long enough to hold enough animals so that the handlers have plenty of time to refill the crowd pen without running out. The chute also needs to be long enough to take advantage of natural following behavior. It is possible to make a chute too long. For large cattle plants processing 100 or more cattle per hour, the minimum length is 80 feet (25m).
An animal standing at the single-file chute entrance must be able to see at least three body lengths up the single file chute before it turns.
Click here to return to the Homepage for more information on animal behavior, welfare, and care.