These are large fans that help to circulate fresh air within the barn.
Proper ventilation ensures a steady supply of oxygen and the removal of moisture, carbon dioxide, ammonia and excessive heat from the barn. Large fans and adjustable openings are built into the walls to allow for continuous air movement throughout the facility without harmful drafts.
Chicken farmers try to keep their barns at a constant temperature all year round. This helps to prevent the barn from being too hot in the summer or too cold in the winter. Some barns also have a misting system in them. If the temperature gets too hot in the summer months, the system gently mists the barn with water to cool the birds down.