Just because you can’t read a sheep’s expression doesn’t mean it isn’t feeling emotion, says animal behaviour scientist Temple Grandin.
When sheep are sick or hurting, they tend not to show it, Grandin told a sheep symposium here recently. Lambs haven’t developed the ability to cover up their fear or pain, but adult sheep mask these emotions.
“When a sheep is separated from a lamb, they show it, but that’s a different fear system. That’s separation anxiety and that’s different from pain,” she said.
Grandin, a professor of animal science at Colorado State University, is a high-functioning autistic, which has given her some insight into how animals react to their surroundings. She is known for designing livestock-handling systems that result in more humane and stress-free handling, but says facilities aren’t the only answer to reducing stress.
“Good corral design is half the equation. The other half is that people realize the importance of good handling.”
CALM PEOPLE, CALM ANIMALS
Grandin said calm animals are productive animals. Studies have shown calm beef cattle gain more weight, and calm dairy cows habituated to people give more milk. When animals are screamed at, they experience stress and their heart rates increase, said Grandin.
“When an animal co-operates with handling and voluntarily goes with the handler, you’ll have less stress than when you force it.”
Circuits in animals’ brains have been mapped to show how they experience stress, which isn’t necessarily only from fear or rough handling. Many animals, including horses, sheep and dogs, do not like being alone and find isolation to be stressful. Grandin said sheep experience two types of stress – fear of rough handling and fear of isolation.
Calm handlers can mean calm sheep, she said.
“When you rough handle animals, their fear and stress goes up and their cortisol (known as the “stress hormone”) goes up.”
Grandin said herding dogs can have the same effect. Studies have shown that sheep’s cortisol levels will rise when they are bitten by dogs. Grandin said it takes about 15 minutes for the sheep’s cortisol level to rise after the animal has been hurt.
Various causes of stress such as transport, temperature and lameness can cumulate, Grandin said. Animals housed in large, noisy operations have higher stress levels. Females who have not given birth have higher estrogen levels and are generally more excitable than males or pregnant females.
Grandin encouraged her audience to get inside their handling systems to see what the animals are seeing. Many animals, such as cattle and sheep, will react strongly to things that seem to be distractions, such as shiny metal objects, flags or chains hanging down.
An animal’s first experience with a new person, new place or new piece of equipment needs to be positive, Grandin said. Animals will remember negative first experiences and this can result in problems.
Animal thinking is very specific, she said. They do not think in language, but store their memories as a collection of pictures, sounds and senses. Animals can make generalizations such as preferring women to men, because they have been hurt by a man in the past, said Grandin.
“When something really bad happens, the animal will associate it with something it was looking at when it happened.”
Grandin cited an example of a horse who was scared of people wearing black cowboy hats, even though the horse would not react to a white cowboy hat or a black cowboy hat placed on the ground.
Animals should get used to different people, vehicles and situations, she said. Animals who are shown should also be habituated to flags, bikes and balloons, all of which move rapidly and are brightly coloured. Animals should be allowed to voluntarily approach and investigate new things.
Grandin also recommends that orphaned animals should be raised with like animals, so that they learn to act like those animals. She said animals such as sheep and cattle should never be touched on the forehead, as this encourages butting. People should never put their forehead next to an animal’s and should never allow an animal to push against them.
People can stop this behaviour by stopping treats or by removing their hands from the animal’s body when an animal does this, not screaming or pushing back, she said.
Grandin is a strong advocate of using leader animals with sheep, who will gladly follow their leader. She said sheep will stick together because they have a much stronger herding instinct than cattle.