In the United States alone, approximately 10 billion land animals are killed each year for food, and 99% of these animals live their entire lives on factory farms, which are large-scale, industrialized farms that are known for treating animals in atrocious ways in the name of profit. Animals living on factory farms live miserable lives from the moment of birth to the moment of slaughter. They are subjected to painful mutilations (e.g., tail-docking and debeaking) without pain relief, confined to cramped cages or overcrowded sheds for their entire lives, denied of opportunities to engage in species-normal behavior, genetically manipulated to grow so large that their bones can’t support their body weight, and they are often victims of random acts of cruelty. Most never see the light of day until they are hauled off to slaughter. Not only are farmed animals subjected to horrible physical pain, but, because of their rich mental lives, they also suffer deeply from loneliness and boredom. They also suffer immense grief when they are separated from their family members, and they moreover feel great fear when they are sent to slaughter. Below, you can find more information about the mental complexity of some of the species that are most exploited in the U.S., and you will learn more about the harms they regularly endure at the hands of the animal agriculture industry.