PSSM1
The Swedish NF Society carried out extensive testing during 2020 and unfortunately a UKbred mare tested positive, but she was not from the currently recognised lines known to be
affected with PSSM1. NFPBCS carried out tests on some deceased stallions to help narrow
down the source – Buckland Dragonslayer, Pilley Prince William, Portmore Prince and
Farriers Rambler all tested clear/negative. We thank our colleagues in Belgium who kindly
tested an old sample of Monkshorn Trooper – again he was negative.

Following this additional testing we have identified the ‘source’ as the mare SKYLARK OF
SOWLEY (b. 1981) – we cannot go back any further than this, but for the record, her sire
was Gilpins Apollo, and dam-sire was Mockbeggar Cream Cracker. Her two daughters
Sowley Ivory (1990) and Sowley Dunlin (1992) were both definitely affected. Testing
continues on the Bella VI daughter line, but so far they are all clear. We do not yet know
the status of the two daughters Sowley Linnet (1988) and Buckland Walnut (1996).

If you have any descendants of these ponies, then please contact us and we can advise you
on how to get your pony tested.

Naturally, it is very disappointing that another ‘pocket’ of PSSM1 has been found, but it is
not really surprising, and we always knew that more would be found. We are very grateful
to all those owners who have had their ponies tested and made their results available to us,
so that we can build a bigger picture. And this new find serves as a timely reminder to all
breeders on how important it is to test all breeding stock. We have heard some very
upsetting stories about affected ponies, and while we cannot do anything about older ponies
bred before we became aware of PSSM1 in our breed, we can stop future owners from
suffering the same heartbreak, and we can stop future ponies from suffering pain.

We know that many mares, fillies and filly foals have been bought recently for breeding
purposes and the responsible way forward is for these mares and fillies to be tested, so that
you know they are definitely clear of PSSM1 before putting them into your breeding
programme. Foals that are ‘clear by parentage’ are given a sticker in Section IX of their
passport.

For current breeding herds, we are always willing to advise on the best way to test your
herd. Generally, it is best to test the older active breeding mares, then their daughters
(provided they are by tested stallions) are clear by parentage, and do not need testing
themselves. Testing is therefore a one-time exercise and many breeders will not have to
test all their mares.

Council has recently drawn up a PSSM1 Breeding Policy, which has immediate effect, and
is posted on the website.

The list of PSSM1 clear stallions is now also available on the website (www.newforestpony.com).

Maj 2021