Oh those cute smushed faces of dogs such as Boxers, Pugs, Boston Terriers, Bullmastiffs and Bulldogs! Dogs with smushed or pushed-in faces are technically known as brachycephalic dogs. The word brachycephalic is derived from Greek words meaning short head, and these dogs’ pushed-in faces are the result of selective breeding for disproportionately short muzzles and noses. These anatomical changes have created the potential for special health concerns that all owners of brachycephalic dogs need to be aware of.

First, brachycephalic dogs are less tolerant of heat than are dogs without pushed-in faces. Dogs’ primary cooling mechanism is breathing and panting. When your dog pants and breathes, excess moisture is removed from the tongue and respiratory tract surfaces. The moisture evaporation cools these parts of your dog’s body and cools the blood located within these body parts. The cooled blood then circulates to other areas within your dog, providing heat relief to the entire body. Brachycephalic dogs, however, must work much harder to breathe and pant and thus cool off. In addition, because the anatomical changes required to create smushed faces often mean that these dogs’ breathing passageways are shortened or pressed flat, there is less surface area for evaporation. Thus, you need to be very careful to avoid situations – including strenuous exercise – in which your brachycephalic dog may become overheated. Overheating can quickly lead to heatstroke, a dangerous condition in which your dog’s body generates more heat than it can get rid of. For more information on heatstroke, click here.