Why a stable identifier matters more than your animal's name

Names exist to call an animal in from the garden, not to link two archives. They carry three structural flaws that no amount of goodwill repairs: they are not unique, they are not stable and they are not always written the same way. In any neighbourhood there are dozens of cats answering to the same name. After an adoption the name almost always changes. Across a prescription, a passport and a shop record you will find different capitalisation, missing accents, and a second name that sometimes appears and sometimes does not.

On top of that sits a less visible trap: even the pair of animal name plus owner surname is not enough, because the owner can change while the animal stays the same. A foster placement, a separation, a move abroad, a transfer from a shelter to a family. If the animal's identity depends on who owns it, every change of ownership breaks the clinical history at precisely the moment it needs to be whole.

A useful identifier has four properties, and they are worth memorising because they let you judge in seconds any code somebody proposes as a key.

• Uniqueness: two different animals cannot share the same value, not even through a plausible transcription error.
• Stability: the value does not change when the owner, the name, the address or the usual clinic changes.
• Verifiability: there is a way to check that the value belongs to the animal in front of you, not just to the paperwork.
• Portability: the value means something outside the system that generated it, otherwise it only serves its creator.

The fourth property is what separates a public identifier from an internal one. A clinic's file number is unique and stable inside that clinic, but outside it means nothing: nobody can use it to tell whether your animal is the one another document is talking about. That is why a serious system always keeps at least two, one internal for its own consistency and one external for talking to the world.

There are few codes in circulation and they play different roles. Mixing them up is a common error: the microchip number identifies the animal, the passport number identifies a document, and a document can be replaced while the animal stays the same.

Three points about microchips are worth clearing up. The standard code has 15 digits, the first three of which indicate the country of registration, or the manufacturer when they start with 900. Standard reading happens by radio frequency at 134.2 kilohertz, which is why a compliant reader also reads chips implanted elsewhere in Europe. Finally, and this bears repeating every time, a microchip is not a tracker: it has no battery, transmits nothing on its own and says nothing about where the animal is. It exists so that a number can be read when somebody brings a reader close.

Three games are played whenever two archives meet, and whoever designs the crossing decides which one to lose. Being too strict about recognising the same animal creates duplicates; being too permissive merges the histories of different animals. The second error is far more serious than the first and far less visible.

1. Duplication: the same animal appears twice with differently spelled names, and vaccinations split between the two records so neither looks complete.
2. Wrong merge: two different animals end up in one record because they share a name, a breed and a birth month. This is the case where a recorded allergy belongs to another animal.
3. Lost link: the record still exists but no code ties it to the documents, so the history is orphaned and starts again at the next visit.
4. Partial link: the connection works for vaccinations and not for laboratory results, because each data flow used a different key.

The most effective defence is banal and almost never applied: when transferring, carry the code, not the description. A file holding 15 microchip digits is worth more than one holding name, breed and coat colour, even though the second looks richer. And when the code is missing, say it is missing instead of substituting resemblance for it.

Five habits hold a clinical history together, cost a few minutes a year and apply identically to the owner, the clinic and the shop providing a service.

1. 1

   Write the code on every document

   The microchip number belongs on the report, on the prescription, on the service record and in the application record. A document without the code is a document somebody will have to relink by hand.

2. 2

   Verify the reading, not the paperwork

   At least once a year, and always before travelling, ask for the chip to be scanned and compare the digits with those written on the documents. A mistyped number survives for years until somebody compares it.

3. 3

   Update contact details where they are registered

   A new phone number or address has to reach the registry where the animal is entered, not only the application. They are separate archives and they do not talk to each other.

4. 4

   Record the change of ownership as an event

   Whoever receives the animal takes the code and the history; whoever hands it over notes the date. If this step stays implicit, the record splits into two stumps with no join date.

5. 5

   Export occasionally and look at what comes out

   A periodic data export shows immediately whether the code travels with the rest or stays on screen only. It is the fastest proof that the history is genuinely portable.

On the tooling side, the product keeps the code as a field of the animal record and carries it along when data leave. The features that bear directly on this topic are listed below, with their real availability.

• Microchip registry inside the animal record, available on web and on iOS, included in the free plan.
• Microchip check in the travel section, available on the web, meant for the pre departure control.
• Pet passport, available on the web and not included in the free plan.
• Single record export and full account data export, both available on the web and included in the free plan.
• QR tag and found page, for the case where somebody finds the animal and needs to reach a contact.
• Read only sharing of the record, useful for a facility that needs to consult without editing.

What is absent deserves saying too. Animiyo queries no national or regional animal registry: the declared external sources cover medicines, substances, foods, weather, maps and calendars, and none of them is an identification database. The practical consequence is that registering and updating a registry entry stays a task to complete with whoever runs it, and the application stores the code without validating it on your behalf.