Identify Pigs by Ear Notching

Guide B-602
Revised by L. Neil Burcham and Jason L. Turner
College of Agricultural, Consumer and Environmental Sciences, New Mexico State University

Authors: Respectively, L. Neil Burcham and Jason L. Turner, Extension Swine Specialist and Extension Horse Specialist, both of the Department of Extension Animal Sciences and Natural Resources, New Mexico State University. (Print-friendly PDF)

An accurate set of records on swine performance is one of the best management tools that a producer can have. In order to keep such records, producers must be able to identify pigs from birth.

The successful manager clips the needle teeth and navel cords as soon after birth as possible. This also offers an opportune time for identification. The simplest method and the one recommended by most breed associations is ear notching. The most common notching system is the 1-3-9 system. For piglets of this size, a small (3/16 to 1/4 inch deep) V-notcher is recommended. If this is your first time ear notching pigs, consult your county Extension agent or an experienced swine producer in your area for assistance to help you develop this skill.

Litter Mark: The right ear is used for litter mark, and all pigs in the same litter must have the same ear notches in this ear. The right ear is on the pig's own right. The litter mark ear is divided into five sections, and each section has a numerical value, either 1, 3, 9, 27, or 81 (Figure 1). Each section, except for 81, can have 1 or 2 notches only.

Fig. 1: Illustration showing numerical values for different ear notch sections in the 1-3-9 system.

Figure 1. Numerical values for different ear notch sections in the 1-3-9 system.


Individual Pig Marks: The left ear is used for notches to show an individual pig's number in the litter. Each pig will have different notches in the left ear. The left ear is divided into three sections, with values of 1, 3, and 9 (Figure 1).

To develop a number, make notches in different parts of the ear in such a way that their numerical values will add up to the desired number. For proper identification to be made, it is essential that the notches be placed in the appropriate area of the ear so that the mark is clearly a 1 versus a 3, or a 9 versus a 27.

Figure 2 shows the proper technique for using a V-notcher, Figure 3 provides examples of ear notches using the 1-3-9 system, and Figure 4 provides examples to help you practice using ear notches.

Fig. 2: Illustration showing proper technique for using a V-notcher.

Figure 2. Using a V-notcher to notch the ears of small pigs for identification.



Fig. 3: Illustrations of example ear notches.

Figure 3. Examples of litter (left number) and individual pig (right number) ear notch numbers.



Fig. 4: Illustrations of un-notched ears to be used for practice.

Figure 4. Practice examples: For the illustrations, draw in the marks that represent the numbers indicated below each figure.

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Revised October 2011 Las Cruces, NM