I
nAugust,theAKCCanineHealthFoundation(CHF)spon-
soredthe2013NationalParentClubCanineHealthCon-
ferenceinSt.Louis.LindaMurrayandIattendedthe
conferenceonbehalfofthePBGVCAandthePBGVHealth
andRescueFoundation,respectively.Weboththoughtthat
itwasafabulousexperience,withexcellenttalks,abundant
opportunitiestointeractwiththespeakers,andlotsoffree
dogbiscuits!Hereisasynopsisofthepresentationsthatwe
heardattheconference.
CanineEpilepsy:Whereweareandwhereweare
going.Epilepsyisaneurologicaldiseasethatdoesn’tstrike
thePBGVcommunityveryoften;however,whenitdoes
occur,theresultsaredevastatingfortheaffecteddogand
family.WilliamThomas,DVM,MS,DACVIM,Professorof
NeurologyandNeurosurgeryattheUniversityofTennessee,
describedthecausesandtreatmentsofcanineepilepsy.
Mostcommonly,theepilepticseizureproducesexcessive
synchronouselectricalactivityinbothsidesofthebrain,
aconditionknownasprimarygeneralizedseizures.The
generalizedtonic-clonicseizurewillstartwithafrightening
periodofmusclecontraction(tonicphase),followedby
rhythmicjerking,paddlingorrunning(clonicphase),which
canbeaccompaniedbyurinationand/ordefecation.These
seizuresgenerallystopspontaneously,afterwhichthedog
maybewobblyandblindfor15to20minutes.Unlike
generalizedseizures,focalseizuresarerestrictedtoone
regionofthebrain.Theclinicalpicturedependsonthearea
thatisaffected.Forexample,electricalactivityinthevisual
cortexmaycausethedogtoseespotsdancingbeforehim,
leadingtoafly-bitingactivity.
Generalizedtonic-clonicseizuresthatlastfiveminutesor
morearereferredtoasstatusepilepticus.Ifaseizuredoesn’t
stopbyfiveminutes,itgenerallywon’tstop;thiscanbelife
threateningorleadtobraindamage.Multipleseizuresthat
occurwithinashortperiodoftimearecalledclusterseizures.
Dr.Thomasreportedthatonetotwopercentofalldogs
willhavesomeoccurrenceofseizuresinhis/herlifetime.
Sometimestheseizurewillbeduetoadistincttumorwithin
thebrainortoametabolicdisorder.Whentheseizureshave
noknownunderlyingcause,theyarereferredtoasidiopathic.
Idiopathicepilepsyissuspectedtohaveageneticbasis.Sixty
percentofdogswithidiopathicepilepsywillsufferstatusor
clusterseizuresatsomepoint.Thisismorecommoninlarge
dogsandresultsinasignificantlyreducedlifespan.
Thetypicalageofonsetofidiopathicepilepsyisbetween
1and5yearsofage.Priortotheirfirstseizureandbetween
seizures,affecteddogsappeartobeperfectlynormal.
Unfortunately,thereisnotesttopredictwhetheradog
willbeaffected.Theclinicaldiagnosisisbaseduponruling
outotherbraindiseases.Importantdiagnostictestsinclude
brainimagingandanalysisofcerebrospinalfluid.Often
thecerebrospinalfluidwillshowsignsofinflammation.
Currenttreatments,phenobarbitalandbromide,don’tfix
theepilepsy;instead,theysuppresstheseizures.Wewerevery
surprisedtolearnthatbromidewasfirstusedinthe1850’s
andphenobarbitalusebeganinthe1920’s.Incredibly,no
treatmentsthataremoreeffectivehaveemergedsincethen.
Whatdoweneedtodotobeatthisterribledisease?Most
importantly,weneedtoidentifythegenemutationsthat
makeadogsusceptibletoseizures.Thiswillgiveusabetter
understandingofwhatisgoingonduringaseizureand
willleadtobetterdiagnostictests.Itwillalsopermit
developmentofmoreeffectivedrugswithfewersideeffects.
Importantly,identificationofcausativegeneswillleadto
developmentofgeneticteststhatwillallowscreeningfor
carriersandaffecteddogs.
Inheritedcardiomyopathies:Understanding
uniqueclinicalandgeneticaspectsforyourbreed.
Cardiomyopathyliterallymeans“sickheartmuscle.”The
AKCwebsitedescribestwotypesofcardiomyopathiesin
dogs:hypertrophiccardiomyopathyanddilatedcardiomy-
opathy.“Inhypertrophiccardiomyopathy,thewallsofthe
chambersoftheheartthicken,leadingtoadecreasein
pumpingefficiency.Thisformofcardiacfailureisquiterare
indogs.Indilatedcardiomyopathy(DCM),thechambersof
theheartincreaseinsizeandthemusclesthatformthewalls
oftheheartstretchthinner.CanineDCMisoneofthecauses
ofcongestiveheartfailureandisthemorecommontypeof
cardiomyopathyindogs.”Mostinheritedcardiomyopathies
areadultonset;thatis,theyarediagnosedwhenthedogis
5yearsorolderratherthanpresentatbirth(congenital).
KathrynMeurs,DVM,PhD,NorthCarolinaStateUniversity
CollegeofVeterinaryMedicine,discussedcardiomyopathies
andtheirmodesofinheritance.Fortunately,PBGVsarenot
afflictedbyinheritedcardiomyopathies.Nevertheless,itis
worthwhiletouseDr.Meurs’sdiscussionofthesediseasesto
illustratetheprinciplesthatgovernallcaninegeneticdiseases.
DCMintheDobermanisanadultonsetdiseasewithan
autosomaldominantinheritance.Autosomalmeansthatthe
traitisnotcarriedonthesexchromosomesandcanaffect
malesandfemalesequally.Dominantmeansthatadogwill
beaffectedifitinheritsonediseasegenefromeitherparent.
AEuropeanstudytoevaluatetheprevalenceofDCMin
Dobermansofallagesrevealedthestunningfactthat58
percentofthebreedexhibitsclinicalsignsofthedisease(G.
Wess,2010).ThegeneforDCMinDobermansintheUnited
Stateshasbeenidentified;itencodesaproteinimportantfor
mitochondrialfunction.The
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www.pbgv.org
December2013
ISaberTails
ITheHealthyPNGV
byLauraLiscumonbehalfofthePBGVCAHealthCommittee
PhotosbyJaneSwanson
The2013AKC
CanineHealth
Foundation
Conference
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