bulls that refused to walk less than a quarter of a mile to a good pasture. Why do cattle do this? It may have something to do with instincts to avoid predators. When cattle learn that a certain area is safe, they become reluctant to move to a new area, which may contain danger.
An experiment that Ken Odde and I conducted at Colorado State University indicated the great strength of a bovine's reluctance to change a previously learned safe route. Cattle were given a choice between an alley that led to a squeeze chute and an alley that they could just walk through. The animals quickly learned to avoid the side where they would be restrained in the squeeze chute. When the alleys were switched, most of the cattle refused to switch sides to avoid restraint. Being held in a squeeze chute is slightly uncomfortable, but not so aversive that the animals were willing to change from the previously learned safe route. When something really painful or disagreeable happens, though, most animals will quickly change to avoid it. Mary Tanner, a student at Colorado State University, found that most cows at a dairy were willing to enter both sides of a milking parlor, but a few were very rigid and always entered on the same side.
Preliminary evidence indicates that the more nervous and excitable cows are the ones that are the most reluctant to change a previously learned safe route. Resistance to change may be partially motivated by attempts to reduce anxiety. In my own experience, minor changes in my high school class schedule or switching from daylight savings time to standard time caused severe anxiety. My nervous system and the nervous systems of some other people with autism are in a state of hyperarousal for no good reason. Before I took antidepressant drugs, my nervous system was constantly ready to flee predators. Insignificant little stresses caused the same reaction as being attacked by a lion. These problems were created by abnormalities in my nervous system. Now that the medication has calmed my nerves, I can take small changes in routine in stride.
One of the most stressful events for semiwild cattle is having people deeply invade their flight zone when they are unable to move away. A person leaning over the top of an alley is very threatening to beef cattle that are not completely tame. Cattle will also balk and refuse to walk through an alley if they can see people up ahead. This is one of the reasons that I designed curved single-file alleys with solid sides. They help keep cattle calmer. The solid sides prevent the animals from being frightened by people and other moving objects outside the alley. A curved alley also works better than a straight one because the cattle are unable to see people up ahead, and each animal thinks he is going back where he came from.
Understanding these kinds of sensitivities made it possible for me to figure out ways to calm flighty antelope at the zoo when other people were convinced that it was impossible to train them to cooperate during veterinary procedures. These procedures were often very stressful, because the animals had to be either shot with a tranquilizer dart or grabbed by people. Antelope can be trained to accept new procedures and novel sights and sounds if those things are introduced gradually and quietly, while the animals are fed treats. I worked with students Megan Phillips, Wendy Grafham, and Mat Rooney to train nyala and bongo antelope to enter a plywood box willingly and stand still during veterinary procedures such as blood testing and injections. The solid sides on the box provided the animals with a sense of safety and security. While they munched on treats, the veterinarian worked on them. During training, we had to take care to avoid triggering a massive fright reaction in these prey-species animals. They had to be carefully desensitized to the sound and movement of the doors on the box, and to people reaching into the box and touching them.
The crafty animals quickly learned to enter the box to get the treats and then kick the moment a blood test was attempted. To stop this, we withheld the treat until the animal stood still and cooperated. Trainers have to discriminate between kicking because of fear and kicking simply to avoid doing something the animal doesn't want to do. Withholding a feed reward will stop learned kicking, but it will have no effect on kicking or thrashing due to fear.
People who work with nonverbal, low-functioning people with autism must similarly be able to determine whether a tantrum or other bad behavior is caused by fear or pain or is a learned avoidance response. Sometimes it's because of pain from sounds that hurt their ears or fear of an unexpected change in routine. Like the cattle and the antelope, autistics are afraid of the unexpected. But sometimes they throw tantrums simply to get attention or to avoid doing a certain activity or school lesson. In one study, aggression and outbursts were greatly reduced in very severely handicapped autistic adults by giving them an object to hold fifteen minutes before they were scheduled to have lunch or ride on the bus. A spoon was used before lunch, and a toy bus was used before riding on the bus. Touch was the only sense that was not confused by sensory jumbling, and holding the object let these people get mentally ready for the next event in their daily routine. There were times when I threw a big tantrum just to watch the grownups react. Observant teachers can tell the difference between a massive fear reaction and the calculated use of bad behavior to avoid tasks the person does not want to do.
People Problems
Mistreatment by people is the number-one cause of animals becoming frightened. The best equipment in the world is worthless unless management controls the behavior of plant employees. When I first started designing equipment, I naively believed that if I could design the perfect system, it would control employee behavior. This is not possible, but I have designed equipment that requires very little skill to operate, provided employees are gentle. Good engineering is important, and well-designed facilities provide the tools that make low-stress, quiet handling at slaughter possible, but employees must operate the system correctly. Rough, callous people will cause distress to animals even if they use the best equipment.
Management attitude is the most important variable that determines how animals are treated. I wouldn't be surprised if this were true of any organization. Livestock handling has greatly improved during the past ten years, and managers are becoming more sensitive about animal welfare, but there still needs to be improvement. It is very painful for me to watch somebody abuse an animal, especially when it happens in one of my systems. Some people buy new equipment and think that it is a substitute for good management. Over the years I have seen animal handling improve with a change in management, and I have seen it get rough and nasty when a good manager left. A good manager serves as a conscience for the employees. He has to be involved enough to care but not so involved that he becomes numb and desensitized. One cannot rely on the foreman to enforce good behavior. This person often becomes immune to animal suffering on the slaughter floor. The manager who enforces good animal handling is usually most effective if he is at the plant-manager level. Someone in a distant headquarters office is often too detached from the reality of the slaughter floor to be concerned.
Plants that have high standards of animal welfare enforce strict codes of conduct. One manager built his office so that he could see the stockyards and the cattle ramp that led into the plant. If he saw employees hitting or whipping the cattle, he called the foreman. Employees who handle thousands of animals often become careless and hard. The people who actually kill the animals should be rotated, and complete automation of the actual killing procedure is good for employee well-being. Automation of killing is especially important in very high-speed plants, with rates of over 150 cattle per hour. A person becomes a zombie when he has to shoot thousands of cattle every day. At slower speeds one can take pride in doing the job humanely and treat each animal with respect, but at high speeds it's all one can do to keep up with the relentless movement of the line.
Management also has to be willing to take the time and make the effort to improve handling methods. Employees have to be trained to understand cattle behavior and use the natural instincts of the animals to assist movement. Trained employees learn to time groups of animals so that they will follow the leader. Each group must be driven up to the single-file alley just as the last animal from the previous group is walking into it. If the next group is driven up too quickly, the cattle or hogs will turn around, because there is no place to go. I love nothing more than to watch a plant I've designed run smoothly and efficiently, knowing that the animals are being treated with decency.
I'm always surprised at the number of people who think that the «jungle» still exists at the Chicago stockyards. The Chicago stockyards have been gone for more than thirty years. When I discuss my job with fellow travelers on airplanes, many ask if a sledgehammer is still used. That was banned by the Humane Slaughter Act in 1958 in all meat plants that sold to the U.S. government. In 1978 the act was strengthened to cover all federally inspected plants that sell meat in interstate commerce. The Humane Slaughter Act requires that cattle, pigs, sheep, and goats must be instantaneously rendered insensible to pain prior to slaughter. The act does not cover poultry or ritual slaughter by any religious faith. The law requires that animals are rendered insensible to pain by either
