A healthy chicken can go a long time without food. Water is the #1 concern. It depends on the temperature and weather conditions. In extremely hot and dry, windy conditions, chickens with no source of water will die in a matter of a day or two. In ideal conditions a chicken could last several days and even longer with no access to water. Given ample access to water a chicken can last week or longer with no food. Egg production will fall off within a couple of days with no access to food.
