NAVLE Prep Questions And Answers
Ax1xyearxoldxGermanxShepherdxisxpresentedxwithxax2-
weekxhistoryxofxlameness.xAlthoughxthexdogxlimpsxonxthexrightxforelegxasxitxentersxthexexa
mxroom,xthexownerxreportsxthatxthexdogxwasxlamexonxthexleftxhindlegxlastxweek.xOnxphysica
lxexam,xthexdogxreactsxpainfullyxonxpalpationxofxthexlongxbonesxofxthexrightxforeleg.xWhichxo
nexofxthexfollowingxchoicesxisxthexmostxlikelyxdiagnosis?
ValuexNormal
99.8xFx(37.7xC)x99.5-102.5xF,x37.2-39.2xC
HR=100xbpmx0-120
RR=24xbrpmx15-34
Ax-xPanosteitis
Bx-xMultiplexcartilaginousxexostosesx
Cx-xHypertrophicxosteodystrophyx
Dx-xHypertrophicxosteopathy
Ex-xRetainedxulnarxcartilagexcoresx-xCORRECTxxANSWER-
Thexhallmarkxofxpanosteitisxisxanxacute-
onsetxshiftingxlegxlamenessxwithxlongxbonexpainxinxaxyoungx(5xmos-
2xyears),xmediumxtoxlargexbreedxdog.
GermanxShepherdsxarexreportedxtoxbexatxhighestxriskxofxpanosteitis.xBassetxhoundsxmayxb
exover-represented.
Hypertrophicxosteodystrophyx(HOD)xisxcharacterizedxbyxbilateralxmetaphysealxpain,xswelli
ngxinxdistalxradiusxandxulna,xfever,xanorexiaxandxdepression.xTypicallyxaxdiseasexofxyoung,x
growingxlargexandxgiantxbreedxdogs.
Hypertrophicxosteopathyx(HO)xisxaxdiffusexperiostealxproliferativexdiseasexofxlongxbonesxinx
dogsxSECONDARYxtoxneoplasticxorxinfectiousxmassesxinxthexthoracicxorxabdominalxcavity.
Multiplexcartilaginousxexostosesxisxcharacterizedxbyxnon-
painfulxossifiedxswellingsxonxmetaphysealxcorticalxsurfacesxofxlongxbones,xvertebrae,xandxr
ibsxinxyoungxdogsxandxcats.xAnimalsxmayxhavexnoxsignsxatxall.
Diagnosisxisxconfirmedxbyxpalpationxandxradiography.xClickxherextoxseexaxradiographxofxcar
tilaginousxexostoses
Retainedxulnarxcartilagexcoresxarexcharacterizedxbyxlamenessxandxeventually,xangularxlim
bxdeformityxinxyoung,xlargexbreedxdogs.
,Ax1-
yearxoldxfemalexspayedxDobermanxPinscherxhasxpresentedxafterxbeingxhitxbyxaxcar.xInitialxc
hestxradiographsxshowxmildxcontusions,xandxthexpatientxappearsxtoxbexotherwisexstable.xAx
rightxmid-shaftxlongxobliquexfemoralxfracturexhasxbeenxidentified.xRoutinexpre-
operativexbloodxworkxisxunremarkable.xAxbuccalxmucosalxbleedingxtestx(BMBT)xisxelevated
xatx6xminutes.xWhatxwillxyouxadministerxpriorxtoxsurgery?
Ax-x1,25xdihydrocholecalciferol
Bx-xDesmopressinxacetate
Cx-xVitaminxK
Dx-xWholexbloodxtransfusionx-xCORRECTxxANSWER-B
Thexcorrectxanswerxisxdesmopressinxacetatex(DDAVP).xAdministrationxofxdesmopressinxre
sultsxinxreleasexofxvonxWillebrandxfactor,xwhichxwillxhelpxthisxpatientxwithxclotting.xGivenxthis
xdog'sxbreedxandxelevatedxBMBTxtherexisxaxveryxstrongxlikelihoodxshexisxafflictedxwithxvonx
Willebrand'sxdisease.xInxDobermansxthisxresultsxinxanxinabilityxtoxformxaxclot.xThisxcanxbexlif
exthreateningxifxthexdogxisxtakenxtoxsurgery.x
AxwholexbloodxtransfusionxdoesxnotxprovidexanxadequatexsourcexofxvonxWillebrandxfactorxb
utxmayxbexnecessaryxifxthexpatient'sxbleedingxcannotxbexcontrolledxdespitexappropriatexpre-
operativexmeasures.x1,25xdihydrocholecalciferolxisxthexactivexformxofxvitaminxDxwhichxaidsx
intestinalxresorptionxofxcalcium.xThexBMBTxdoesxnotxassessxfactorsx2,x7,x9,xorx10xandxthere
forexvitaminxKxisxnotxindicated.
Ax1.5-
yearxoldxQuarterxHorsexgeldingxisxpresentedxtoxyouxforxsymmetricxataxia,xweakness,xandxs
pasticityxofxallxlimbs,xbutxworsexinxthexhindxlimbs.xWhenxwalking,xthexhorsexfrequentlyxdrags
xhisxtoesxandxthexhindxlimbsxfrequentlyxinterferexwithxonexanother.xBasedxonxthexsignalment
,xhistoryxandxphysicalxexaminationxfindings,xwhichxofxthexfollowingxisxthexmostxlikelyxcausex
ofxthesexclinicalxsigns?
Ax-xEquinexProtozoalxMyeloencephalitisx(EPM)
Bx-xEquinexMotorxNeuronxDiseasex(EMND)
Cx-xBotulism
Dx-xEquinexDegenerativexMyeloencephalopathyx(EDM)
Ex-xCaudaxEquinaxSyndromex-xCORRECTxxANSWER-D
ThexhorsexinxthisxquestionxhasxclinicalxsignsxmostxconsistentxwithxEDM;xcervicalxvertebralx
malformationx(wobblers)xisxalsoxaxpossibility,xbutxwasxnotxprovidedxasxanxanswer.xThexcaus
exofxEDMxisxunknown,xbutxthisxdiseasextypicallyxaffectsxyoungxhorsesx(<x2-
3xyearsxofxage;xbutxolderxhorsesxcanxdevelopxdisease).xClinicalxsignsxarexaxresultxofxdiffusex
neuronalxfiberxdegenerationxofxvariousxportionsxofxthexcentralxnervousxsystem.xThisxdiseas
exhasxbeenxassociatedxwithxlowxserumxvitaminxExconcentrations,xsuggestingxthatxoxidative
xdamagexmayxplayxaxrolexinxthexdevelopmentxofxdisease.x
,EMNDxisxtypicallyxassociatedxwithxmusclextremors,xshiftingxofxweightxwhilexstanding,xmuscl
exatrophyxandxrecumbency.xBotulismxisxassociatedxwithxgeneralizedxmusclexweakness.xC
audaxequinaxsyndromexcausesxanalgesiaxofxthexperineum.xEPMxcanxcausexaxrangexofxclini
calxsigns,xbutxisxtypicallyxwithxasymmetricxneurologicxdeficits.
Ax1.5-year-oldxspayedxfemalexcatxpresentsxwithxax7-
dayxhistoryxofxvocalizing,xrolling,xandxallowingxaxmalexneuteredxcatxinxthexhouseholdxtoxmou
ntxher.xThexcatxhasxgonexthroughxonexsimilarxepisodex1xmonthxago.xShexotherwisexhasxbee
nxbehavingxnormallyxandxhasxnoxotherxhealthxproblems.xYouxperformedxanxovariohysterect
omyxonxthexcatxatx3xmonthsxofxage.xYouxperformxvaginalxcytologyxwhichxshowsxsomexcornif
iedxepithelialxcellsxbutxisxinconclusive.xYouxmeasurexserumxlutenizingxhormonexofx0.2xng/m
lx(normalxforxanxovariectomizedxfemalexisx>1xng/ml).xWhichxofxthexfollowingxisxthexmostxapp
ropriatexcoursexofxaction?
Ax-xOrderxMRIxofxthexbrainxtoxrulexoutxaxpituitaryxtumor
Bx-xMeasurexserumxtestosteronexlevels
Cx-xExploratoryxlaparotomyxtoxremovexthexovarianxremnant
Dx-xMeasurexserumxestrogenxandxprogesteronexlevelsx-xCORRECTxxANSWER-C
Thisxisxaxclassicxdescriptionxofxovarianxremnantxsyndrome,xwhichxisxwhenxaxcatxgoesxintoxe
strusxafterxpreviouslyxhavingxanxovariohysterectomyx(OVH).x
ThisxcanxoccurxanywherexfromxweeksxtoxyearsxafterxOVHxandxtypicallyxthexclinicalxsignsxco
nsistentxwithxestrusxarexsufficientxtoxconcludexthatxthexcatxisxinxestrusxandxhasxovarianxtissu
expresent.xAdditionalxdiagnosticxtestsxthatxarexconsistentxwithxovarianxremnantxsyndromexi
nclude:x
Serumxestrogenx>70xpmol/Lxindicatexthatxthexcatxhasxestrogenxproductionxfromxthexovary.x
Thexproblemxwithxthisxtestxisxthatxestrogenxmeasurementsxmayxfluctuatexandxcanxbexunreli
able.xSerumxprogesteronex>6xnmol/Lxafterxinducedxovulationxisxsufficientxtoxconcludexthatx
corporaxluteaxformedxandxreleasedxprogesterone.xTestingxforxserumxLHxlevelsxcanxalsoxhel
pxconfirmxthexdiagnosis.xInxintactxqueens,xLHxisxconsistentlyxmaintainedxatxbasalxlevelsxdue
xtoxnegativexfeedbackxfromxovarianxestradiolxsecretion.xAfterxOVH,xthisxcontrolxisxlostxandxL
Hxconcentrationsxincrease.xLHx<1xng/mLxisxconsistentxwithxthexpresencexofxanxovaryxasxitxis
xinxthisxcase.x
Surgeryxisxthextreatmentxofxchoice.xManyxpractitionersxpreferxtoxdoxsurgeryxduringxestrusxor
xdiestrusxwhenxthexovarianxtissuexisxenlargedxandxeasierxtoxlocate.xRemnantsxmayxbexbilat
eralxsoxaxcompletexexploratoryxlaparatomyxisxnecessary.xOvarianxtissuexisxmostxcommonly
xatxthexovarianxpediclexbutxcanxalsoxbexinxthexmesenteryxorxelsewhere.x
YouxshouldxbexawarexthatxovarianxremnantxsyndromexisxNOTxassociatedxwithxnewxgraduat
esxorxinexperiencedxsurgeonsx(itxisxnotxlikelyxthexfaultxofxthexinitialxsurgeon).xItxisxsuspectedx
thatxaccessoryxovarianxtissuexseparatexfromxthexovaryxwithinxthexovarianxligamentxorxprope
rxligamentxofxthexovaryxmayxbecomexfunctionalxandxcausexthisxconditionxinxmostxcases.
, Ax10xyearxmalexcastratedxGermanxShepherdxdogxpresentsxforxanxacutexonsetxofxptosis,xdro
opingxofxthexlip,xandxdroopingxofxthexcheekxallxonxthexleftxside.xWhatxnervexhasxbeenxdamag
ed?
Ax-xCNxVI
Bx-xCNxV
Cx-xCNxIII
Dx-xCNxVIIx-xCORRECTxxANSWER-D
ThexcorrectxanswerxisxCNxVII.xThisxisxthexfacialxnervexwhichxisxresponsiblexforxmotorxofxthexf
acialxmusclesxasxwellxasxsensationxinxthexearxandxlacrimation.xCNxVxisxmostlyxresponsiblexf
orxsensation.xCNxIIIxisxthexoculomotorxnervexandxservesxinxmovementxofxthexeye.xCNxVIxisxa
lsoxinvolvedxinxmovementxofxthexeye.
Ax10xyearxoldxQuarterhorsexgeldingxpasturedxinxthexnortheasternxUnitedxStatesxisxpresente
dxforxweaknessxandxdepression.xThexownerxreportsxthatxthexhorse'sxurinexisxanxunusuallyxd
arkxbrownxcolor.
Onxphysicalxexam,xthexhorsexisxtachycardicxandxtachypneic.xThexmucousxmembranesxarex
axdarkxyellowishxbrown.
Thexhorse'sxplasmaxhasxaxpinkxtinge.xAxCBC,xbloodxsmear,xbiochemistryxpanel,xandxurinal
ysisxindentifyxintravascularxhemolyticxanemia,xhemoglobinemia,xmethemoglobinemia,xand
xhemoglobinuria.
ErythrocytesxarexseenxonxthexbloodxsmearxwithxHeinzxbodiesxandxeccentrocytosis.
Ingestionxofxwhichxonexofxthexfollowingxplantsxisxmostxlikelyxtoxcausexofxthisxspectrumxofxclin
icalxsignsxinxthisxcase?x
Ax-xTetradymiaxsppx(Horsebrush)
Bx-xQuercusxsppx(Oak)
Cx-xAcerxrubrumx(Redxmaple)x
Dx-xVeratrumxsppx(Skunkxcabbage)
Ex-xXanthiumxsppx(Cocklebur)x-xCORRECTxxANSWER-C
IngestionxofxAcerxrubrumx(Redxmaple)xisxmostxlikelyxthexcausexofxhemolyticxanemiaxandxth
exresultantxpathologyxinxthisxhorse.
Wiltedxorxdryxleavesxandxbarkxofxredxmaplextreesxcontainxoxidantsxwhichxdamagexredxblood
xcellx(RBC)xmembranes,xresultingxinxthexformationxofxHeinzxbodiesxandxeccentrocytes.xAcu
texintravascularxhemolysis,xhemoglobinemia,xmethemoglobinemia,xhemoglobinuria,xandx
methemoglobnuriaxfollow.
Clinicalxsignsxofxtoxicityxinclude:xweakness,xdepression,xtachypnea,xtachycardia,xicterus,xc
yanosis,xandxbrownxdiscolorationxofxbloodxandxurine.
Ax1xyearxoldxGermanxShepherdxisxpresentedxwithxax2-
weekxhistoryxofxlameness.xAlthoughxthexdogxlimpsxonxthexrightxforelegxasxitxentersxthexexa
mxroom,xthexownerxreportsxthatxthexdogxwasxlamexonxthexleftxhindlegxlastxweek.xOnxphysica
lxexam,xthexdogxreactsxpainfullyxonxpalpationxofxthexlongxbonesxofxthexrightxforeleg.xWhichxo
nexofxthexfollowingxchoicesxisxthexmostxlikelyxdiagnosis?
ValuexNormal
99.8xFx(37.7xC)x99.5-102.5xF,x37.2-39.2xC
HR=100xbpmx0-120
RR=24xbrpmx15-34
Ax-xPanosteitis
Bx-xMultiplexcartilaginousxexostosesx
Cx-xHypertrophicxosteodystrophyx
Dx-xHypertrophicxosteopathy
Ex-xRetainedxulnarxcartilagexcoresx-xCORRECTxxANSWER-
Thexhallmarkxofxpanosteitisxisxanxacute-
onsetxshiftingxlegxlamenessxwithxlongxbonexpainxinxaxyoungx(5xmos-
2xyears),xmediumxtoxlargexbreedxdog.
GermanxShepherdsxarexreportedxtoxbexatxhighestxriskxofxpanosteitis.xBassetxhoundsxmayxb
exover-represented.
Hypertrophicxosteodystrophyx(HOD)xisxcharacterizedxbyxbilateralxmetaphysealxpain,xswelli
ngxinxdistalxradiusxandxulna,xfever,xanorexiaxandxdepression.xTypicallyxaxdiseasexofxyoung,x
growingxlargexandxgiantxbreedxdogs.
Hypertrophicxosteopathyx(HO)xisxaxdiffusexperiostealxproliferativexdiseasexofxlongxbonesxinx
dogsxSECONDARYxtoxneoplasticxorxinfectiousxmassesxinxthexthoracicxorxabdominalxcavity.
Multiplexcartilaginousxexostosesxisxcharacterizedxbyxnon-
painfulxossifiedxswellingsxonxmetaphysealxcorticalxsurfacesxofxlongxbones,xvertebrae,xandxr
ibsxinxyoungxdogsxandxcats.xAnimalsxmayxhavexnoxsignsxatxall.
Diagnosisxisxconfirmedxbyxpalpationxandxradiography.xClickxherextoxseexaxradiographxofxcar
tilaginousxexostoses
Retainedxulnarxcartilagexcoresxarexcharacterizedxbyxlamenessxandxeventually,xangularxlim
bxdeformityxinxyoung,xlargexbreedxdogs.
,Ax1-
yearxoldxfemalexspayedxDobermanxPinscherxhasxpresentedxafterxbeingxhitxbyxaxcar.xInitialxc
hestxradiographsxshowxmildxcontusions,xandxthexpatientxappearsxtoxbexotherwisexstable.xAx
rightxmid-shaftxlongxobliquexfemoralxfracturexhasxbeenxidentified.xRoutinexpre-
operativexbloodxworkxisxunremarkable.xAxbuccalxmucosalxbleedingxtestx(BMBT)xisxelevated
xatx6xminutes.xWhatxwillxyouxadministerxpriorxtoxsurgery?
Ax-x1,25xdihydrocholecalciferol
Bx-xDesmopressinxacetate
Cx-xVitaminxK
Dx-xWholexbloodxtransfusionx-xCORRECTxxANSWER-B
Thexcorrectxanswerxisxdesmopressinxacetatex(DDAVP).xAdministrationxofxdesmopressinxre
sultsxinxreleasexofxvonxWillebrandxfactor,xwhichxwillxhelpxthisxpatientxwithxclotting.xGivenxthis
xdog'sxbreedxandxelevatedxBMBTxtherexisxaxveryxstrongxlikelihoodxshexisxafflictedxwithxvonx
Willebrand'sxdisease.xInxDobermansxthisxresultsxinxanxinabilityxtoxformxaxclot.xThisxcanxbexlif
exthreateningxifxthexdogxisxtakenxtoxsurgery.x
AxwholexbloodxtransfusionxdoesxnotxprovidexanxadequatexsourcexofxvonxWillebrandxfactorxb
utxmayxbexnecessaryxifxthexpatient'sxbleedingxcannotxbexcontrolledxdespitexappropriatexpre-
operativexmeasures.x1,25xdihydrocholecalciferolxisxthexactivexformxofxvitaminxDxwhichxaidsx
intestinalxresorptionxofxcalcium.xThexBMBTxdoesxnotxassessxfactorsx2,x7,x9,xorx10xandxthere
forexvitaminxKxisxnotxindicated.
Ax1.5-
yearxoldxQuarterxHorsexgeldingxisxpresentedxtoxyouxforxsymmetricxataxia,xweakness,xandxs
pasticityxofxallxlimbs,xbutxworsexinxthexhindxlimbs.xWhenxwalking,xthexhorsexfrequentlyxdrags
xhisxtoesxandxthexhindxlimbsxfrequentlyxinterferexwithxonexanother.xBasedxonxthexsignalment
,xhistoryxandxphysicalxexaminationxfindings,xwhichxofxthexfollowingxisxthexmostxlikelyxcausex
ofxthesexclinicalxsigns?
Ax-xEquinexProtozoalxMyeloencephalitisx(EPM)
Bx-xEquinexMotorxNeuronxDiseasex(EMND)
Cx-xBotulism
Dx-xEquinexDegenerativexMyeloencephalopathyx(EDM)
Ex-xCaudaxEquinaxSyndromex-xCORRECTxxANSWER-D
ThexhorsexinxthisxquestionxhasxclinicalxsignsxmostxconsistentxwithxEDM;xcervicalxvertebralx
malformationx(wobblers)xisxalsoxaxpossibility,xbutxwasxnotxprovidedxasxanxanswer.xThexcaus
exofxEDMxisxunknown,xbutxthisxdiseasextypicallyxaffectsxyoungxhorsesx(<x2-
3xyearsxofxage;xbutxolderxhorsesxcanxdevelopxdisease).xClinicalxsignsxarexaxresultxofxdiffusex
neuronalxfiberxdegenerationxofxvariousxportionsxofxthexcentralxnervousxsystem.xThisxdiseas
exhasxbeenxassociatedxwithxlowxserumxvitaminxExconcentrations,xsuggestingxthatxoxidative
xdamagexmayxplayxaxrolexinxthexdevelopmentxofxdisease.x
,EMNDxisxtypicallyxassociatedxwithxmusclextremors,xshiftingxofxweightxwhilexstanding,xmuscl
exatrophyxandxrecumbency.xBotulismxisxassociatedxwithxgeneralizedxmusclexweakness.xC
audaxequinaxsyndromexcausesxanalgesiaxofxthexperineum.xEPMxcanxcausexaxrangexofxclini
calxsigns,xbutxisxtypicallyxwithxasymmetricxneurologicxdeficits.
Ax1.5-year-oldxspayedxfemalexcatxpresentsxwithxax7-
dayxhistoryxofxvocalizing,xrolling,xandxallowingxaxmalexneuteredxcatxinxthexhouseholdxtoxmou
ntxher.xThexcatxhasxgonexthroughxonexsimilarxepisodex1xmonthxago.xShexotherwisexhasxbee
nxbehavingxnormallyxandxhasxnoxotherxhealthxproblems.xYouxperformedxanxovariohysterect
omyxonxthexcatxatx3xmonthsxofxage.xYouxperformxvaginalxcytologyxwhichxshowsxsomexcornif
iedxepithelialxcellsxbutxisxinconclusive.xYouxmeasurexserumxlutenizingxhormonexofx0.2xng/m
lx(normalxforxanxovariectomizedxfemalexisx>1xng/ml).xWhichxofxthexfollowingxisxthexmostxapp
ropriatexcoursexofxaction?
Ax-xOrderxMRIxofxthexbrainxtoxrulexoutxaxpituitaryxtumor
Bx-xMeasurexserumxtestosteronexlevels
Cx-xExploratoryxlaparotomyxtoxremovexthexovarianxremnant
Dx-xMeasurexserumxestrogenxandxprogesteronexlevelsx-xCORRECTxxANSWER-C
Thisxisxaxclassicxdescriptionxofxovarianxremnantxsyndrome,xwhichxisxwhenxaxcatxgoesxintoxe
strusxafterxpreviouslyxhavingxanxovariohysterectomyx(OVH).x
ThisxcanxoccurxanywherexfromxweeksxtoxyearsxafterxOVHxandxtypicallyxthexclinicalxsignsxco
nsistentxwithxestrusxarexsufficientxtoxconcludexthatxthexcatxisxinxestrusxandxhasxovarianxtissu
expresent.xAdditionalxdiagnosticxtestsxthatxarexconsistentxwithxovarianxremnantxsyndromexi
nclude:x
Serumxestrogenx>70xpmol/Lxindicatexthatxthexcatxhasxestrogenxproductionxfromxthexovary.x
Thexproblemxwithxthisxtestxisxthatxestrogenxmeasurementsxmayxfluctuatexandxcanxbexunreli
able.xSerumxprogesteronex>6xnmol/Lxafterxinducedxovulationxisxsufficientxtoxconcludexthatx
corporaxluteaxformedxandxreleasedxprogesterone.xTestingxforxserumxLHxlevelsxcanxalsoxhel
pxconfirmxthexdiagnosis.xInxintactxqueens,xLHxisxconsistentlyxmaintainedxatxbasalxlevelsxdue
xtoxnegativexfeedbackxfromxovarianxestradiolxsecretion.xAfterxOVH,xthisxcontrolxisxlostxandxL
Hxconcentrationsxincrease.xLHx<1xng/mLxisxconsistentxwithxthexpresencexofxanxovaryxasxitxis
xinxthisxcase.x
Surgeryxisxthextreatmentxofxchoice.xManyxpractitionersxpreferxtoxdoxsurgeryxduringxestrusxor
xdiestrusxwhenxthexovarianxtissuexisxenlargedxandxeasierxtoxlocate.xRemnantsxmayxbexbilat
eralxsoxaxcompletexexploratoryxlaparatomyxisxnecessary.xOvarianxtissuexisxmostxcommonly
xatxthexovarianxpediclexbutxcanxalsoxbexinxthexmesenteryxorxelsewhere.x
YouxshouldxbexawarexthatxovarianxremnantxsyndromexisxNOTxassociatedxwithxnewxgraduat
esxorxinexperiencedxsurgeonsx(itxisxnotxlikelyxthexfaultxofxthexinitialxsurgeon).xItxisxsuspectedx
thatxaccessoryxovarianxtissuexseparatexfromxthexovaryxwithinxthexovarianxligamentxorxprope
rxligamentxofxthexovaryxmayxbecomexfunctionalxandxcausexthisxconditionxinxmostxcases.
, Ax10xyearxmalexcastratedxGermanxShepherdxdogxpresentsxforxanxacutexonsetxofxptosis,xdro
opingxofxthexlip,xandxdroopingxofxthexcheekxallxonxthexleftxside.xWhatxnervexhasxbeenxdamag
ed?
Ax-xCNxVI
Bx-xCNxV
Cx-xCNxIII
Dx-xCNxVIIx-xCORRECTxxANSWER-D
ThexcorrectxanswerxisxCNxVII.xThisxisxthexfacialxnervexwhichxisxresponsiblexforxmotorxofxthexf
acialxmusclesxasxwellxasxsensationxinxthexearxandxlacrimation.xCNxVxisxmostlyxresponsiblexf
orxsensation.xCNxIIIxisxthexoculomotorxnervexandxservesxinxmovementxofxthexeye.xCNxVIxisxa
lsoxinvolvedxinxmovementxofxthexeye.
Ax10xyearxoldxQuarterhorsexgeldingxpasturedxinxthexnortheasternxUnitedxStatesxisxpresente
dxforxweaknessxandxdepression.xThexownerxreportsxthatxthexhorse'sxurinexisxanxunusuallyxd
arkxbrownxcolor.
Onxphysicalxexam,xthexhorsexisxtachycardicxandxtachypneic.xThexmucousxmembranesxarex
axdarkxyellowishxbrown.
Thexhorse'sxplasmaxhasxaxpinkxtinge.xAxCBC,xbloodxsmear,xbiochemistryxpanel,xandxurinal
ysisxindentifyxintravascularxhemolyticxanemia,xhemoglobinemia,xmethemoglobinemia,xand
xhemoglobinuria.
ErythrocytesxarexseenxonxthexbloodxsmearxwithxHeinzxbodiesxandxeccentrocytosis.
Ingestionxofxwhichxonexofxthexfollowingxplantsxisxmostxlikelyxtoxcausexofxthisxspectrumxofxclin
icalxsignsxinxthisxcase?x
Ax-xTetradymiaxsppx(Horsebrush)
Bx-xQuercusxsppx(Oak)
Cx-xAcerxrubrumx(Redxmaple)x
Dx-xVeratrumxsppx(Skunkxcabbage)
Ex-xXanthiumxsppx(Cocklebur)x-xCORRECTxxANSWER-C
IngestionxofxAcerxrubrumx(Redxmaple)xisxmostxlikelyxthexcausexofxhemolyticxanemiaxandxth
exresultantxpathologyxinxthisxhorse.
Wiltedxorxdryxleavesxandxbarkxofxredxmaplextreesxcontainxoxidantsxwhichxdamagexredxblood
xcellx(RBC)xmembranes,xresultingxinxthexformationxofxHeinzxbodiesxandxeccentrocytes.xAcu
texintravascularxhemolysis,xhemoglobinemia,xmethemoglobinemia,xhemoglobinuria,xandx
methemoglobnuriaxfollow.
Clinicalxsignsxofxtoxicityxinclude:xweakness,xdepression,xtachypnea,xtachycardia,xicterus,xc
yanosis,xandxbrownxdiscolorationxofxbloodxandxurine.
