The one biological fact that changes every recommendation
Dogs do not sweat through their skin. Sweat glands in dogs are located almost exclusively in their paw pads, a surface area so small it contributes negligibly to cooling. The primary mechanism is panting: rapid, shallow breathing that evaporates moisture from the tongue, mouth, and upper respiratory tract. A 2006 paper in the Journal of Thermal Biology confirmed that evaporative respiratory cooling accounts for the dominant share of heat dissipation in domestic dogs, with paw-pad sweating playing a minor supplementary role.
