Visual identification of both cows and calves is an important management tool. Identification of calves makes it easier to monitor them to ensure they are doing well and to check on any that might be sick or have some type of problem.
The most common form of identification of calves is a visual eartag. Visual eartags come in a few different sizes and either two-piece (tag and button) or one-piece options. The same size tag used in cows can also be used in newborn calves if desired. Larger size tags are easier to read and desirable if some of the heifer calves will be kept as replacements. Tag and text color also influence tag readability. White or yellow tags with black text are common because many people find them easier to read. In some situations, tag color may be used to identify different sexes or groups. Tags can also be custom printed with numbers on both the front and the back or with additional information like the owner’s name or phone number.
Calves may be tagged in numerical order or to match their dams; both strategies have advantages. One advantage of numerical order is the calf can be tagged without knowing the dam. Calves can then be watched to match the pair up later.
Which ear the tag is placed in depends on user preference. Consider how the alley and squeeze chute are set up, and put the tag in the ear that will be easiest to read. Many producers place tags in the left ear for this reason. Putting the tag in the left ear is also beneficial for replacement heifers because it doesn’t interfere with brucellosis tattoos or tags.
Eartags should be applied about halfway between the base of the ear and the tip of the ear in the middle rib of the ear. Whenever possible, try to avoid any large blood vessels. When applying tags, it is important to keep the eartag applicator and the tags clean to help prevent infections. Disinfecting the equipment can also be helpful. If an infection does develop and the ear starts to hang lower than normal, the eartag should be removed to allow the ear to heal. After the ear is healed, the tag can be cleaned and reused or a new tag can be applied.