Heaves is a respiratory disease of horses 6 years of age or older, characterized by difficulty breathing, chronic coughing, abnormal lung sounds and decreased exercise tolerance. These signs manifest themselves as a result of narrowing of the small airways of the lungs. This narrowing is caused by inflammation and thickening of the lung tissues, constriction of the smooth muscles surrounding the lungs and accumulation of mucous and exudate within the lumens of the lungs. The end result is known as emphysema or a trapping of air in the lungs.
Extreme cold temperatures are dangerous not only to humans, but to animals as well. If at all possible, for the overall health of your pet, keep him/her inside with you and your family. If your dog or cat stays outside, you must provide adequate shelter. 
