New Policy for Stallions regarding Warmblood Fragile Foal Syndrome (WFFS)

May 9, 2018

New Policy for Stallions regarding Warmblood Fragile Foal Syndrome (WFFS)


Media Contact: Jennifer Keeler, Yellow Horse Marketing, May 10, 2018

Statement from the KWPN-NA  Regarding New Mandatory Testing of Stallions for Warmblood Fragile Foal Syndrome
By Jennifer M. Keeler, Yellow Horse Marketing for the KWPN-NA

As previously reported in April, the office of the Royal Dutch Warmblood Association of North America (KWPN-NA) has been closely monitoring the recent developments with Warmblood Fragile Foal Syndrome (WFFS). At that time, our organization encouraged breeders to voluntarily test their breeding stock while we waited for any official policy updates from the KWPN in Holland.

Now, those policy updates have arrived. After the recent publications regarding this disease, it has been found that three KWPN-approved stallions carry the WFFS gene, and it is currently not clear which (if any) other stallions may be carriers of this gene as they have not been tested. Since breeding season is in full swing and there is a sense of urgency regarding this testing, the KWPN-NA has been officially notified that effective immediately, the General Board of the KWPN is requiring testing for all active approved KWPN stallions of which offspring have been registered in the past five years, as well as any stallions that are currently participating in the performance test. All test results must be provided to the KWPN and will be made publicly available on the KWPN website. This decision immediately leads to transparency regarding possible carriage of the WFFS gene.  Therefore, here in North America, the KWPN-NA will now require testing for all activated Approved, Licensed and Foalbook stallions. These results will also be published on the KWPN-NA website so that breeders can make informed decisions.

At this time, testing is available through the UC Davis Veterinary Genetics Laboratory for a discounted price of just $30.00 if tested through the KWPN-NA, and our office will facilitate and coordinate the testing at UC Davis Veterinary Genetics Laboratory. Key points for stallion owners to know about this testing are:

  • If your stallion has already been tested or you have already gotten a notification from the KWPN in Holland that they are testing your stallion, we ask you to please email, fax or mail a copy of the certificate to the KWPN-NA office so that we do not order another test for your stallion. Tests will begin to be ordered on Friday, May 11th.
  • Sufficient DNA is usually still available ‘on file’ with UC Davis from a horse’s original hair sample for KWPN-NA registration to conduct this additional test. But if a stallion was tested through another registry, if the sample was converted from blood, or if it originated in the Netherlands, a new sample will be required and we will be forwarding a new DNA kit to send to UC Davis. If DNA hair samples are not available on the stallion, a semen test can also be done.
  • The KWPN-NA office will pre-order the tests and will receive the results directly from UC Davis. Our office will pass on these results to the stallion owner after the owner submits payment directly to the KWPN-NA to reimburse for the test. No additional administrative or handling fees will be applied.

Through this mandatory testing, breeders can make better choices for their programs and prevent WFFS non-viable foals from being born. The carrier status of stallions for WFFS will be published on the KWPN-NA website and in the stallion directory. Please note the results of this testing do not affect the status of the stallions with the KWPN breeding program and they will remain as approved or licensed, and will continue to be able to be activated regardless of their carrier status. The KWPN is still discussing how this testing will be integrated in the breeding program for mares.

It is the responsibility and in the best interest of all breeders to guarantee a high-quality and healthy breeding program, and the KWPN-NA thanks stallion owners for their cooperation. For more information, visit the KWPN-NA website at