Quote Originally Posted by joepythons
Gently open his mouth and look to see if it has a slimy like substance inside.If it does then yes its URI.If its totaly clear then it could be something else.Since you had the heat problems in the begging and leaving soon it will not hurt to have him looked at.Even if it turns out he is ok it will ease your mind .Keep us posted
URI can be identified way earlier than the point where enough mucus starts to develop in the mouth that it is easily distinguished from saliva ... at that point it has potentially progressed pretty far along and can actually be in the process of moving to the lower lung.

A vet and a culture is the absolute best way to determine whether or not your animal has a URI if you don't have any previous experience with the disease.

-adam