What importing semen from a stallion abroad actually requires

We spent a good part of today writing to breeders outside the UK — Canada, the United States, Australia, Ireland, a run of studs in Germany. A fair number of them are exactly the kind of small, careful operation GenoVaq exists for: a stallion standing at a family farm, semen collected on site, a handful of straws sent out each season to mares an ocean away. It's a reminder that a rare breed's gene pool rarely respects a border, and that the paperwork behind an international straw of semen is one of the least understood parts of the whole trade — including, if we're honest, by us until we sat down to check it properly.

So this is the other side of a listing that simply says "semen available, overseas enquiries welcome": what a buyer bringing that semen into the UK is actually agreeing to stand behind, and what a seller sending it out is required to have already done.

The disease the whole process exists to rule out

The document that governs almost everything here is the Horserace Betting Levy Board's Code of Practice for Contagious Equine Metritis, or CEM — a bacterial venereal disease first identified in Newmarket in 1977, caused by an organism called Taylorella equigenitalis. An infected stallion typically shows no outward signs at all. The bacteria simply sit on the penis and sheath, ready to pass into every mare he covers or every straw collected from him. CEM is notifiable in the UK under the Infectious Diseases of Horses Order 1987, and the Code of Practice that followed its 1977 outbreak is credited with eradicating it from the UK breeding population — it still turns up sporadically here, and rather more often on the Continent.

Two other organisms, Klebsiella pneumoniae and Pseudomonas aeruginosa, are covered by the same Code for the same reason: both can be sexually transmitted, both can contaminate collected semen if a stallion's glands become infected, and neither produces symptoms a breeder would necessarily notice.

What has to happen before a straw is ever frozen

Before any stallion is used for mating, teasing or semen collection in a new breeding season, the Code requires two sets of swabs — taken from the urethra, the urethral fossa and the sheath — at an interval of no less than seven days, cultured both aerobically and microaerophilically. Only once both sets come back clear is he considered free from infection for that season.

For a stallion collected specifically for artificial insemination, there's a further step: alongside the swabs, a sample of raw semen — collected with no extender or antibiotic added, which would otherwise mask a low-level infection — has to be cultured too, and confirmed negative before any of that semen is used to inseminate a mare. If the stallion is going to stand for the whole season, he's swabbed again partway through, and any straws frozen from a subsequent, infected ejaculate have to be destroyed, one straw pulled from every batch and tested, not sampled.

None of this is optional groundwork a breeder can skip because their stallion "seems fine." A PCR test can flag an active infection within a day, but the Code is explicit that PCR alone isn't accepted for official import or export certification in the UK — only the slower culture result is, because culture is what confirms the organism is actually viable and transmissible, not just present.

What travels with the semen

Once a stallion has cleared testing, the export side of the paperwork is handled through an Export Health Certificate — for semen leaving Great Britain for the EU or Northern Ireland, that's certificate 8407, issued by the Animal and Plant Health Agency and applied for online through an official vet, who has to be separately registered with APHA to certify it. The certificate exists to say, formally, that this specific consignment of semen, from this specific stallion, was collected under the conditions the Code requires, and is what the paperwork claims it is.

The Code puts the responsibility on the receiving end just as plainly as the sending end: a mare owner "should not accept semen for AI without obtaining evidence that the donor stallion was free from infection when the semen was collected," and when semen is imported, it "should be accompanied by documentary evidence of freedom from infection with all three bacteria and the original import certificate." In other words, the certificate isn't paperwork to file away once the flask arrives — it's the thing a buyer is supposed to check before a single straw is thawed, in the same way we'd want anyone checking what a stud fee actually buys to read the terms before the mare travels.

Where this leaves a listing

None of this changes what we do with a stallion's page — we still build it from what's publicly published and what the breeder confirms, the same as any other listing, and we still take no fee and no cut of the arrangement between breeder and buyer. But "semen available, ships internationally" is doing a lot of quiet work in that sentence, and a buyer is entitled to ask the same plain question we'd want asked of a passport or a licence: who tested this, when, and can I see the certificate. It sits alongside what a horse passport actually proves and what a stallion's licence actually proves as one more document that looks routine and is, underneath, the record of a specific person doing specific, timed, repeatable work to rule out a specific disease — not a formality, but the whole reason the straw is safe to use at all.

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Sources

• Code of Practice for Contagious Equine Metritis (CEM), Klebsiella pneumoniae and Pseudomonas aeruginosa — HBLB Codes of Practice
• Guidelines on Artificial Insemination (AI) — HBLB Codes of Practice
• Equine semen collected, processed and stored after 20 April 2021 and dispatched to the EU and Northern Ireland: certificate 8407 — GOV.UK / Animal and Plant Health Agency
• Conditions for the import of equine semen — USDA Animal and Plant Health Inspection Service

— Rene