Livestock enclosures, also known as PENS, are structures used to contain and protect animals such as cattle, sheep, and horses. They are typically made of wood, metal, or wire fencing and provide a safe and secure environment for the animals. PENS are an important part of animal husbandry and are used to keep animals from straying, prevent them from coming into contact with predators, and provide a place for them to rest and graze.