In fact, shocking a cow or hitting her can reduce milk yield by 10 percent. Cows that are fearful of people are less productive, documents Australian Paul Hemsworth. Fearfulness was determined by the degree of restlessness the cow displayed when a person was close to her during milking. Cows that avoided people and became restless when a person was nearby had lower milk production. Still further, observations at a large dairy indicated that tame cows gave more milk.
Animals have excellent memories for both good and bad experiences.
Research on the brain by Joseph LeDoux at New York University shows that animals can experience fear memories that cannot be erased. These fear memories are located in a part of the brain called the amygdala which is the lower more primitive part of the brain under the cortex. Fear memories are permanent. Back in the times when cows were wild animals, they would be more likely to be eaten by predators if they forgot where they had encountered a lion. Over time, animals can learn to override a fear memory and become less fearful of the place where a scary experience occurred.