It is hard to tell without a thermometer. Sometimes their nose will be warm, but not all the time. Just get a rectal thermometer at a drug store or Wal-mart, they are fairly cheap and check it, in fact we just use a regular one and it works fine. Just lube it up with KY or Vaseline and insert it about 1/2 to 3/4 of an inch in his rectum to check. Their normal temp is 100 to 102.5 deg. F.