30 Saber Tails Spring 2016
Petit Basset Griffon Vendéen Club of America
O
FA lists the prevalence of HD (radiographic) by
breed on it’s website and PBGVs are listed as 97th
out of the 173 breeds for which at least 100 evaluations
have been completed to date. The general trend is that
larger dogs have more dysplasia than smaller dogs.
F
inally, the cost effectiveness of widespread screen-
ing for any condition needs to be taken into account.
The common CERF (eye) screening is generally under
$50 and is frequently available free at national special-
ties. The POAG test (without the current subsidy) will
run about $70 for fees and postage. OFA hip exams
without anesthesia will start at $150 and range upwards
to more than $400 plus a $35 OFA filing fee. Consider-
ing all the dogs tested in the years since hip evaluations
became part of PBGVCA’s CHIC requirements, 8 dogs
with radiographic HD were identified at an approximate
total cost to all owners of at least $40,000. Extrapolating
from what we do know about clinical outcomes, it seems
likely that few of these dogs will ever exhibit clinical
symptoms of hip dysplasia.
I
f the CHIC program is to be an effective tool used by
parent clubs to promote wider testing of breeding
stock, it needs to address the health issues in the breed
as they currently exist and to provide a mechanism for
adjustments as these health issues change over time.
The POAG test is definitive and predictive to the extent
that no dogs affected with POAG should ever be pro-
duced again. It is possible that in a few generations
even carriers will disappear from the gene pool. At some
point in time, it might very well be pointless to test for
a gene that has been effectively eliminated from the
breed.
I
t is useful to think of CHIC criteria as a fluid system
that will evolve as different health issues are identified,
targeted, and hopefully significantly minimized if not
eliminated. It is in this context that the Board of Direc-
tors has elected to add POAG testing and eliminate hip
evaluations from the screening protocol.
T
his change in CHIC criteria does not imply that PB-
GVCA believes that hip screening evaluations never
provide useful information for the owner/breeder. Ca-
nine athletes in particular may benefit from the informa-
tion provided by hip and other orthopedic evaluations.
Additionally, dogs with an unusually strong potential
to affect the future of the breed (frequently used sires,
top winning dogs in any venue) should probably be
screened for any potential genetic issue for which a test
whose x-rays indicated some degree of dysplasia are not
identified publically on the OFA database. Using the OFA
search function to identify those dogs whose owners gave
permission to publish the results, regardless of outcome,
10 dogs were identified with a rating of mild hip dysplasia
and 2 were listed as having moderate hip dysplasia. An
attempt was made to determine the clinical outcome for
these 12 dogs and this was accomplished for only five
of the listed dogs, none of which ever displayed clinical
symptoms. The sample size is small and incomplete but
there is little evidence that the OFA rating system is a good
predictor of eventual clinical HD in individual PBGVs.
O
f perhaps greater concern is the possible unreliability
of these ratings in predicting risk to the offspring of
tested dogs. Using the same OFA database, the pedi-
grees of all twelve radiographically dysplastic dogs were
retrieved. Five of the dogs were out of tested sires and
dams: one was out of two parents who tested good, four
were from matings between one good and one fair parent.
Four dogs were out of matings between one tested and
one untested parent in which all of the tested parents were
fair. Three dogs were from untested parents most of whom
were imported. If knowing the hip status of breeding stock
was useful in assessing the risk of passing on hip dysplasia
to offspring, it isn’t obvious from this casual survey.
T
he incidence of any level of HD (radiographic) in PBGVs,
up to its inclusion as a CHIC criterion in 2007,
in the US is approximately 10% of tested dogs or less than
2% of the total population of PBGVs registered with AKC.
The incidence since the CHIC program was implemented
for PBGVs is about 3% of tested dogs (perhaps less than
0.5% of all dogs. It is true that the picture painted by the
OFA database is incomplete in that there is no requirement
that owners submit negative results to OFA (unless they
want an ‘official’ reading) and there is no requirement that
these results be published (unless they want to receive a
CHIC number). It is also true that the sample size is too
small and too spotty to make any claims about statisti-
cal significance. Anecdotal information is just that--but
reports of clinical hip dysplasia in PBGVs are extremely rare.
T
here is also no doubt that extensive screening for hip
dysplasia has had a beneficial effect in those breeds
with high levels of the condition. These breeds are invari-
ably large breeds such as Newfoundlands, Saint Bernards
and several retriever breeds.