Trachea is a part of the upper respiratory tract. It connects the upper parts of respiratory system to the lower parts. The lungs are the lower part of respiratory system. If the conduction of air from upper to the lower respiratory tract is blocked, the animal requires emergency attention. This blockage is mostly due to any foreign object engulfed by the dog. The inner surface of trachea contains microscopic hair in a mucus layer that trap any inhaled particles. If these particles reach lungs without being filtered, they can cause damage to the lungs. The trapped material is collected by the hair on the trachea and sent back to mouth. If the animal is unable to clear the trapped debris, this can lead to infection in the lungs. Some cats are more likely to develop this problem as compared to other species and breeds.