Swine Ear Notching Laws in South Dakota: What Every Pig Producer Needs to Know
August 12, 2026
If you raise pigs in South Dakota — whether for a purebred breeding program, 4-H, or commercial production — understanding ear notching rules can save you from compliance problems when you sell, show, or move animals across state lines. Ear notching is one of the oldest swine identification methods in the country, and it still plays a real role in modern South Dakota livestock law.
This guide breaks down exactly when ear notching is legally recognized, how the standard notching system works, when a registry record is required, and how ear notching stacks up against ear tags, tattoos, and RFID in today’s regulatory environment. You will also find the South Dakota-specific rules that govern swine identification on and off your premises.
What Is Swine Ear Notching and When It Is Used in South Dakota
Ear notching is a permanent identification method in which small V-shaped cuts are made in specific locations on a pig’s ears. Each notch position carries a numerical value, and the combination of notches on both ears gives every pig a unique litter-and-individual number that lasts its entire life. No tag can fall out, no ink can fade — the mark stays with the animal.
In South Dakota, ear notching is used across several production contexts. Purebred breeders apply it at birth to satisfy breed registry requirements. Producers moving livestock across state lines may rely on registry-recorded notches as a recognized form of official identification. Youth exhibitors in 4-H and FFA programs also use the system to document their project pigs from enrollment through fair day.
Ear notching provides a permanent ID system, gives individual identity to all animals, and is an inexpensive means of identification that enables producers to keep an accurate set of records. That combination of permanence and low cost is why the practice remains common on South Dakota farms even as electronic options expand.
Pro Tip: Notch piglets at 1–3 days old whenever possible. If pigs are notched at 1–3 days of age, the task is much easier. If you allow pigs to become large (100 lb), the task is considerably more demanding mentally and physically.
When Ear Notching Qualifies as Official Identification in South Dakota
Not every set of ear notches on a pig counts as “official identification” under state or federal law. The distinction matters because official ID is what allows swine to move interstate legally and appear on certificates of veterinary inspection (ICVIs).
Ear notching qualifies as official identification when the ear notching has been recorded in the book of record of a purebred registry association. Without that registry record, the notches are useful for on-farm management but do not satisfy the legal identification standard for interstate movement or official health paperwork.
The South Dakota Animal Industry Board (SDAIB) lists the forms of ID it accepts for swine on official documents. Official eartags (NUES and 840/AIN tags) are used for ID on interstate certificates of veterinary inspection, test charts, and other records. USDA premises tags printed with a unique herd management number may be used as official ID on non-slaughter swine. Breed registration tattoos are used on ICVIs and test charts for swine. Ear notching with a registry record fits within this framework as an accepted alternative for purebred animals.
Effective as of March 11, 2013, USDA’s animal disease traceability rule established general regulations for livestock that move interstate. Under the rule, unless specifically exempted, livestock moved interstate must be officially identified and accompanied by an interstate certificate of veterinary inspection. South Dakota producers moving registered purebred swine should carry a copy of the registration certificate alongside the ICVI to confirm the notch record.
Important Note: Copies of issued ICVIs must be maintained for two years for swine. Keep those records organized and accessible on your premises.
How the 1-3-9 Ear Notching System Works
The most common notching system is the 1-3-9 system. It assigns numerical values to specific positions on each ear, and you identify a pig by adding up the values of all notches present. The system is straightforward once you know the layout.
The litter number is notched in the pig’s right ear and the individual pig number in the pig’s left ear. Every pig from the same litter shares identical notches in the right ear; only the left ear differs to show each piglet’s unique number within that litter.
Right ear — litter number: The litter mark ear is divided into five sections, and each section has a numerical value, either 1, 3, 9, 27, or 81. Each section, except for 81, can have 1 or 2 notches only. In zones 1, 3, 9, and 27, there can only be two notches, thus if there are two notches in all four zones, that would represent Litter 80. Then a notch in zone 81 basically doubles the system.
Left ear — individual pig number: 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.
To read a pig’s identity, you add up the notch values in each ear separately. If a pig has notches at the 9 and 3 locations on the right ear, the litter number is 12. If the left ear has a single notch in the bottom inside (3) location, that pig is individual number 3 from litter 12. That pig’s full identity is written as 12-3.
One orientation rule trips up many beginners. The reference to left and right ear refers to the pig’s left or right ear, as viewed from the rear of the pig. Left and right does not refer to the viewer’s left or right in a situation where the pig is facing the viewer. A practical shortcut: a good way to remember which is the left ear is to always look the pig in the face. Then, if read left-to-right, it would always be litter number then pig number.
| Ear | Purpose | Zone Values | Max Notches per Zone |
|---|---|---|---|
| Right (pig’s own right) | Litter number | 1, 3, 9, 27, 81 | 2 (except 81 — only 1) |
| Left (pig’s own left) | Individual pig number | 1, 3, 9 | 2 per zone |
Avoid making notches too shallow, as they may become hard to read or possibly heal shut. Leave at least 1/4 inch between notches, and avoid making notches too close to the head. For piglets of this size, a small (3/16- to 1/4-inch-deep) V-notcher is recommended.
Ear Notching for Purebred Registry Compliance in South Dakota
For South Dakota producers raising registered purebred swine, ear notching is often a breed association requirement, not just a personal management choice. Major swine breed registries — including those for Duroc, Hampshire, Yorkshire, Berkshire, and Chester White — have historically required ear notching as the primary method of permanent identification for registration purposes.
The simplest method and the one recommended by most breed associations is ear notching. When you submit a litter registration to a breed registry, the notch pattern you record becomes the permanent identifier in the association’s book of record. That recorded entry is what elevates the notch from a farm management tool to legally recognized official identification under federal traceability rules.
Certified Pedigreed Swine (CPS), one of the major registry bodies for show and purebred swine, uses the notching system as a core enrollment tool. The right ear is used for litter mark. All pigs in the same litter must have the same notches in the right ear. The left ear identifies the individual pig. Submitting accurate notch records at registration ensures the pig can be traced back to your herd at any point in its life.
If you are showing purebred pigs at South Dakota county fairs or state-level shows, confirm with the show secretary whether a copy of the registration certificate must accompany the animal. Each state in which registry shows are hosted has regulations for animal health and the identification of swine that move across state lines. These regulations vary from state to state. Carrying the registration paperwork eliminates disputes at check-in.
Pro Tip: You will often see similar notches among pigs from the same litter, with only the left ear differing to reflect each pig’s unique number. Use this as a quick visual check to confirm you have notched a litter consistently before the piglets are weaned.
Ear Notching vs. Ear Tags, Tattoos, and RFID in South Dakota
South Dakota producers have several identification options available, and understanding when each method satisfies official requirements — and when it does not — keeps your operation compliant and your paperwork clean.
The SDAIB recognizes multiple forms of official ID depending on the class of swine and the purpose of movement. Official eartags are a recognized form of ID. USDA backtags can be used only when used on swine moving in slaughter channels. Official swine tattoos issued and authorized by state or federal animal health officials apply to swine moving in slaughter channels.
On the RFID front, the landscape is shifting quickly. APHIS is offering no-cost radio frequency identification (RFID) eartags to eligible swine producers. This program will enhance the speed and accuracy of disease response efforts across the swine industry. On August 21, 2025, USDA APHIS announced its new initiative to provide no-cost RFID ear tags for show and exhibition swine beginning fall of 2025. South Dakota received a significant allocation of these tags — South Dakota received 79,000 from Michigan as part of a broader redistribution effort among states.
Swine producers and state animal health officials can now order RFID eartags at no cost. To place an order, producers must have a valid premises identification number and provide shipping and contact information. They must also report the number of sows onsite (for commercial sow farms) or the number of show pigs (for exhibition swine).
| ID Method | Permanent? | Official ID for Interstate Movement? | Best Use Case in SD |
|---|---|---|---|
| Ear Notching | Yes | Yes — only if recorded with a purebred registry | Purebred breeding programs, 4-H/FFA |
| Official Ear Tags (NUES/840) | Yes | Yes | All classes of swine, ICVI documentation |
| RFID Tags (840 EID) | Yes | Yes | Sow farms, exhibition swine, disease traceability |
| Breed Registry Tattoo | Yes | Yes — if recorded with registry; not accepted by all states | Purebred breeding swine, show animals |
| USDA Backtag | No | Slaughter channels only | Market hogs going directly to slaughter |
Tattoos share some characteristics with ear notching but work differently in practice. Ink placed inside the ear lasts the life of the animal and cannot be lost or altered easily, which is why breed registries often require them. The limitation is readability: you need to restrain the animal and flip the ear to read a tattoo, making it impractical for quick sorting at a distance. Ear notches, by contrast, are visible without restraint once you know the system.
For producers who show pigs through the National Swine Registry, the NSR requires all animals being exhibited at NSR or NJSA events to be identified with an official, permanently-numbered ear tag. Ear notches alone will not satisfy that show-day requirement — you will need an official tag as well.
State-Specific Swine Identification Rules That Affect Ear Notching in South Dakota
South Dakota’s swine identification framework is governed by the South Dakota Animal Industry Board (SDAIB) under SDCL Title 40, with federal overlay from USDA APHIS regulations. Understanding where state rules align with — and where they add to — federal requirements helps you stay compliant in every scenario.
A livestock owner may choose to identify animals using any methods set forth in 9 C.F.R. part 86, as adopted on January 9, 2013, as well as any additional methods that are later approved by the South Dakota Animal Industry Board. This gives the SDAIB authority to recognize identification methods beyond the federal baseline, including registry-recorded ear notching for purebred swine.
Any identification program implemented pursuant to the relevant statutes shall be for the sole purpose of maintaining animal health and ensuring the safety of the food supply. That stated purpose shapes how the SDAIB evaluates new ID technologies and maintains existing ones like ear notching.
For intrastate movement within South Dakota, official ear tags and breed registration tattoos cover most scenarios. When swine cross state lines, the federal traceability rule kicks in and the ICVI requirement applies. The federal traceability rule requires that all issued ICVIs be forwarded to the state office in Pierre within 7 calendar days of the date of issue. Your veterinarian handles that submission, but you should confirm it happened.
If your operation also raises other livestock species alongside swine, it is worth reviewing the open range laws in South Dakota and the state’s broader livestock transportation rules, since identification requirements can interact with movement and fencing obligations. Producers keeping goats alongside pigs should also check goat ownership laws in South Dakota for species-specific ID rules.
For exhibition swine specifically, the SDAIB has been active in distributing RFID tags to producers. USDA APHIS announced its initiative to provide no-cost RFID ear tags for show and exhibition swine beginning fall of 2025. Once available, producers and state animal health officials can order swine tags on the Merck Animal Health website. The board discussed that this will be beneficial but stressed the importance of notifying producers.
- Ear notching alone is not sufficient official ID for interstate movement — registry documentation must accompany the animal.
- ICVIs for swine must be submitted to the SDAIB office in Pierre within 7 calendar days of issuance.
- South Dakota recognizes breed registration tattoos on ICVIs, but not all destination states do — verify before you ship.
- RFID (840 EID) tags are now available at no cost to South Dakota sow producers and exhibition swine owners through the USDA APHIS swine identification program.
- Contact the South Dakota Animal Industry Board to confirm current accepted ID methods before interstate shipment.
Key Insight: South Dakota’s identification rules for swine are tied directly to the federal Animal Disease Traceability framework. Maintenance of an efficient, reliable system of animal disease traceability is essential to decrease negative effects and to preserve animal health when a disease outbreak occurs. Effective traceability can also limit the number of animal owners impacted by an outbreak and reduce the economic impact to herd owners and affected communities.
Staying current with both SDAIB guidance and USDA APHIS updates is the most reliable way to keep your swine identification program compliant. If you are uncertain whether your current notch records satisfy a specific movement or show requirement, contact the SDAIB directly or work with your accredited veterinarian before the animals leave your premises. You can also explore related South Dakota animal law topics — from pet import laws to backyard chicken regulations — to get a fuller picture of how the state manages livestock and animal ownership across species.