188.8.131.52. Thermocouple types
There are different types of thermocouples, with different combinations of wire metals, e.g. NiCr/NiAl (Type K), Cu/Constantan (Type T), etc. Thermocouple types may differ considerably in sensitivity (and, irrelevant for biological applications, measurement range). Make sure to always use the correct type of thermocouple, matching the type and size of connector input on your electronic thermometer.
For honey bee body temperature measurement, thermocouple wires have to be thin (diameter <70 µm). For "grab and stab" measurement of body (core) temperature (Stone and Willmer, 1989) the thermocouples have to be inserted within hypodermic needles. Most practical are thermocouples inserted in "thermoneedles" by the manufacturer (available ready for use and in different sizes for example at Omega Engeneering, Inc.).