Changes

Under moderate heat stress, ruminants pant with a closed mouth.  Under significant heat stress, however, all animals pant with open mouths.  This means that air with a high water content cannot condense on the mucosa of the nasal cavity, thus maximising the heat lost through evaporation.  There is also some evaporation from the oral membranes.

Under moderate heat stress, ruminants pant with a closed mouth.  Under significant heat stress, however, all animals pant with open mouths.  This means that air with a high water content cannot condense on the mucosa of the nasal cavity, thus maximising the heat lost through evaporation.  There is also some evaporation from the oral membranes.