The most effective way of taking a pet's temperature is by placing a thermometer in his/her rectum for 30-60 seconds (blech!). Digital thermometers ~ well-lubricated of course ~ are commonly used and do alert the user with a beep when the thermometer is ready to be read. Not all dogs and cats, needless to say, are always too happy with this procedure!
Love... and other stuff too
Office Coordinators -cum- Receptionists
Animal Relocations Officers