Swine Ear Notching Laws in Indiana: What Every Producer Needs to Know

If you raise pigs in Indiana — whether for a 4-H project, a registered purebred herd, or a commercial operation — understanding swine ear notching laws can save you from compliance headaches at weigh-in, at the sale barn, or at the state line. Ear notching is one of the oldest forms of livestock identification in the country, and Indiana still recognizes it under specific, well-defined conditions.

The rules are not complicated once you know which category your animals fall into. This guide walks you through exactly when ear notches count as official identification in Indiana, how the notching system works, what purebred registries require, and how notching stacks up against tags, tattoos, and RFID under state law.

What Is Swine Ear Notching and When It Is Used in Indiana

Ear notching is a permanent method of pig identification in which small V-shaped cuts are made in specific positions along the edges of both ears. Each position on each ear corresponds to a number, and the combination of notches encodes a pig’s litter number and individual number within that litter. It is a traditional method of identification in swine in which pigs are identified based on their birth order within a given farrowing.

Because the notches are cut into cartilage, they remain readable for the animal’s entire life — unlike ear tags, which can fall out or be removed. Ear notching is a permanent form of identification that, if done correctly, will provide identification for the pig’s entire life, and it serves as the enrollment ID for 4-H swine enrollment in Indiana.

In Indiana, ear notching appears in three main contexts: 4-H youth livestock programs, purebred breed registry compliance, and official state identification for registered purebred animals moving between premises. Each context carries its own rules, and mixing them up is a common source of problems at county fairs and livestock markets alike.

Pro Tip: Always orient yourself by looking the pig in the face before reading ear notches. Confusion over which ear is the “left ear” can easily occur depending on whether you view the pig from the front or the rear — looking the pig in the face means reading left-to-right will always give you litter number then pig number.

When Ear Notching Qualifies as Official Identification in Indiana

Not every notched pig has official ID status under Indiana law. The Indiana State Board of Animal Health (BOAH) sets the rules for what counts as official swine identification, and ear notching occupies a narrow but important slot in that list.

BOAH recognizes several forms of identification as official for swine, and some forms are acceptable for exhibition while others are only for approved commercial group or lot movements. Ear notching falls squarely in the first category — it works for exhibition and for movement of registered purebred animals, but it does not substitute for an official ear tag on crossbred or commercial hogs.

Ear notching is accepted as official identification, but only registered purebred swine may move on their ear notch — crossbred swine must have an approved official ear tag. This single rule defines the practical boundary of ear notching as official ID in Indiana. If your pig is not registered with a recognized breed association, a notch alone will not satisfy state identification requirements for movement or exhibition.

At the federal level, ear notching qualifies as official swine identification when the ear notching has been recorded in the book of record of a purebred registry association. Indiana’s rules align with this federal standard under the USDA’s Animal Disease Traceability (ADT) program. Indiana’s BOAH requirements went into effect on January 1, 2015, and Indiana’s rule aligns with USDA’s Animal Disease Traceability program.

For producers moving swine into Indiana from another state, a Certificate of Veterinary Inspection (CVI) is required for entry into Indiana for all swine, both domestic and wild, with limited exceptions for animals traveling directly to slaughter or to a licensed market. The animal’s official identification — including any registered ear notch — must appear on that CVI.

Important Note: Exhibitors should always contact the show manager to verify what form or forms of ID are acceptable for a specific event, since requirements can vary between county fairs, the Indiana State Fair, and other exhibitions.

How the 1-3-9 Ear Notching System Works

The standard ear notching system used in Indiana and across the United States divides each ear into zones, with each zone assigned a numeric value. Reading the notches in both ears together gives you a unique two-part identifier: the litter number and the individual pig number within that litter.

The pig’s right ear is the Litter Ear, where the litter number is notched, and the pig’s left ear is the Individual Pig Ear, where the pig’s number within the litter is notched. This right-ear-for-litter, left-ear-for-individual convention is universal across breed registries and 4-H programs in Indiana.

The zones in each ear carry different values. There are five designated zones — 1, 3, 9, 27, and 81 — in the Litter Ear and three designated zones — 1, 3, and 9 — in the Individual Pig Ear. You add up the values of all notches present in each ear to get the litter number and individual number, respectively.

Here is how the math works in practice:

• A single notch in the “9” zone of the right ear = Litter 9
• A notch in the “3” zone plus a notch in the “1” zone of the left ear = Individual pig 4
• That pig would be recorded as Pig 9-4

Each ear is divided into four parts, each area representing the numbers 1, 3, 9, or 27, and in each of the four areas you can have up to two notches. When those positions are filled in the right ear, an 81-notch placed at the tip doubles the system, and only one notch may be at the 81 position. This extension allows the system to handle large operations with many litters per farrowing season.

The Certified Pedigreed Swine registry notes that the right ear is used for the litter mark, all pigs in the same litter must have the same notches in the right ear, the left ear identifies individual pigs in the same litter, and all littermates must have different notches in the left ear.

Ear	Purpose	Zone Values Available	Max Notches per Zone
Right Ear	Litter Number	1, 3, 9, 27, 81	2 (1 at zone 81)
Left Ear	Individual Pig Number	1, 3, 9	2 per zone

Ear notches help breeders maintain accurate records for registration and for health records on the farm, including vaccination records. When you notch correctly and record the notch in your breed registry’s book, you create a paper trail that supports both state traceability requirements and your own herd management records.

Ear Notching for Purebred Registry Compliance in Indiana

If you show or sell registered purebred swine in Indiana, your ear notches must match the notches recorded on the animal’s registration certificate. This is not just a best practice — it is a hard rule enforced at weigh-in at county fairs and at the Indiana State Fair.

All 4-H gilts must be ear notched, and the ear notches of purebred gilts must be recorded on their registration papers, which must be presented for verification to the Swine Superintendent. The same standard applies to purebred barrows. Purebred gilts without registration certificates, gilts whose ear notches do not match the notches recorded on their registration certificate, and gilts whose registration certificate indicates the animal was mis-notched will not be allowed to show in purebred classes.

Mis-notching is a disqualifying error — not a paperwork fix. If a pig was notched incorrectly at birth and the registration certificate reflects the wrong notch, the animal cannot compete in purebred classes regardless of its actual breed quality. These gilts will be eligible for the crossbred section, so long as their ear notches match the notches listed on the 4-H member’s online swine enrollment information and they have met all other 4-H rules.

For producers using the Purdue Extension ear notching reference guide, the key takeaway is that notching must happen correctly at farrowing and must be reported to the registry before the animal changes hands. Retroactive corrections are not recognized by BOAH or by breed associations as a substitute for proper original records.

For the Indiana State Fair, in addition to ear notching ID for barrows and gilts, DNA hair samples are required for all swine to be eligible, and the hair samples are due in the county Extension office by May 15th. This additional requirement means ear notching alone is not sufficient for ISF eligibility — plan ahead for both steps.

Pro Tip: Notch piglets within the first few days of birth when the ear cartilage is soft and the procedure causes minimal stress. Recording the notch with your breed registry immediately after farrowing prevents discrepancies between the physical notch and the registration paperwork.

Ear Notching vs. Ear Tags, Tattoos, and RFID in Indiana

Ear notching is one of several identification methods BOAH recognizes for swine, and each method has a different scope of acceptance. Knowing which method applies to which situation keeps you compliant whether you are moving animals to a sale barn, crossing state lines, or entering a show ring.

Swine should bear only one official ear tag per animal placed in either ear, but in addition to one official ear tag, the animal may also bear an approved official tattoo, approved USDA back tag, registered ear notches, and/or a Group Identification Number (GIN). This layered approach means ear notches and official ear tags are not mutually exclusive — they can coexist on the same animal.

Here is how the main identification methods compare under Indiana and federal rules:

ID Method	Accepted for Purebred Movement	Accepted for Crossbred/Commercial	Accepted for Exhibition	Accepted for Slaughter Channels
Registered Ear Notch	Yes	No	Yes (purebred only)	No
Official Ear Tag (USDA-approved)	Yes	Yes	Yes	Yes
PIN Tag	Yes (with unique animal ID)	Yes (slaughter)	Yes (with unique animal ID)	Yes
Tattoo (premise ID)	Yes	Yes (market hogs, 4+ characters)	Varies	Yes
RFID / Electronic Implant	Limited (breed-registered only in some contexts)	Emerging	Varies by show	Varies

Tattoos of at least four characters may be used on market hogs but may not be used on sows or boars. This restriction makes tattoos unsuitable as the sole identification method for breeding stock moving through Indiana markets, which is another situation where a registered ear notch or official ear tag becomes necessary.

RFID and electronic identification are growing in the swine industry, but Indiana has not mandated RFID for swine the way it has for cattle ear tags. Ear notching, still used in some swine and registry systems, raises welfare concerns due to the tissue removal involved — a consideration that has pushed some producers toward electronic alternatives for commercial herds, even while notching remains the standard for purebred registry work.

For producers who sell breeding stock to major pork processors, PIN tags are intended for culling breeding swine, and to be official for interstate movement and exhibition, PIN tags must include a premises number and unique animal ID imprinted by the manufacturer. A registered ear notch does not replace a PIN tag for this purpose.

State-Specific Swine Identification Rules That Affect Ear Notching in Indiana

Indiana’s swine identification framework sits within a broader state and federal regulatory structure. Several state-specific rules directly shape when and how ear notching fits into your compliance plan.

BOAH requires premises registration of all sites associated with the sale, purchase, and/or exhibition of cattle, swine, sheep, goats, and cervids. This means that before your ear notches can function as official ID for movement purposes, your farm must have a registered Premises ID Number (PIN) on file with BOAH. You can contact BOAH at animalid@boah.in.gov or (317) 544-2400 to register or retrieve a lost premises ID.

Record-keeping requirements also apply to anyone who distributes official animal identification devices. Any person or organization, including a veterinarian, that distributes official animal identification devices is required to keep a record for five years of the device identification number as well as the name and address of the device recipient, and these records must be kept in a readily accessible record system and/or entered into a USDA-approved database.

At livestock markets, ear notches are part of the transaction record. Licensed livestock markets in Indiana must maintain a record of individual animal identification, including ear tags, ear notches, back tags, tattoos, or brands. Making a false entry or statement in any report or record is illegal, as is willfully removing, destroying, changing, or concealing the true identity or identification of any animal required by state or federal law to be identified. Altering notches to misrepresent an animal’s litter or registry status is a legal violation, not just a fair rule infraction.

For swine moving out of Indiana, unless otherwise exempt, if covered animals are moved interstate they must be officially identified and accompanied by an interstate certificate of veterinary inspection or other movement document. A registered ear notch satisfies the identification requirement for purebred swine crossing state lines, but the CVI requirement is separate and must also be met.

Indiana also prohibits certain swine from entering the state entirely. Feral swine and swine that originate from a herd that has been fed garbage may not be transported into Indiana. No form of identification — ear notch or otherwise — overrides this prohibition.

Important Note: Pre-entry permits are required for most swine entering Indiana that need a paper CVI. A pre-entry permit is required for all swine that require a paper certificate of veterinary inspection, but a pre-entry permit is not required when the CVI is submitted to BOAH electronically prior to movement. Filing electronically can simplify the process significantly.

Indiana’s swine identification rules connect to a wider set of animal ownership and livestock laws in the state. If you manage other livestock or pets alongside your swine operation, you may also want to review the goat ownership laws in Indiana and the beekeeping laws in Indiana, both of which involve separate BOAH premises registration considerations. For broader livestock and animal law context, the animal cruelty laws in Indiana outline the legal standards that apply to all livestock handling practices in the state.

Producers showing animals at county fairs or the Indiana State Fair should also be aware that show-specific rules — including what ID forms are accepted at weigh-in — can differ from BOAH’s baseline movement rules. Always confirm requirements with the show superintendent well before the event, and keep your registration papers and premises ID documentation accessible throughout fair season. For questions about other livestock-related regulations that may affect your farm, the rooster laws in Indiana and backyard chicken laws in Indiana cover poultry-side rules that often apply to mixed-species operations.

The bottom line: ear notching remains a legally recognized and practically useful identification method in Indiana, but only within its defined lane. Keep your notches accurate, register them with your breed association, maintain your premises ID, and pair notches with the additional documentation BOAH requires for movement and exhibition. When in doubt, contact BOAH directly at (317) 544-2400 or visit the BOAH swine entry requirements page for the most current guidance.