elasmobranch medicine: history, clinical exams and...

Elasmobranch medicine: Elasmobranch medicine:

history, clinical exams and history, clinical exams and

diagnosticsdiagnostics

Catherine A. Hadfield MA VetMB MRCVSCatherine A. Hadfield MA VetMB MRCVS

January 2008January 2008

What is an elasmobranch?What is an elasmobranch?

•• Jawed fish (gnathostoma)Jawed fish (gnathostoma)

•• Cartilaginous skeleton (chondrichthyes)Cartilaginous skeleton (chondrichthyes)

•• Maxilla not fused to skullMaxilla not fused to skull

What is an elasmobranch?What is an elasmobranch?

•• 1,125 extant species 1,125 extant species (Compagno 2005)(Compagno 2005)

•• Shark ordersShark orders–– Fusiform, lateral gill slitsFusiform, lateral gill slits

•• Batoid orders Batoid orders –– skates, rays, guitarfish, sawfishskates, rays, guitarfish, sawfish–– DV flattened, ventral gill slitsDV flattened, ventral gill slits

ElasmobranchsElasmobranchs

•• Respiratory systemRespiratory system

–– Gills for gaseous exchangeGills for gaseous exchange

•• 5 (or 65 (or 6--7) paired gill arches 7) paired gill arches

–– Use pressure changes to move water over gillsUse pressure changes to move water over gills

•• In through mouth or spiraclesIn through mouth or spiracles

•• Out through gill slitsOut through gill slits

–– Some ram ventilatorsSome ram ventilators


•• Cardiovascular systemCardiovascular system

–– 2 chambered heart2 chambered heart

–– Hematopoiesis in spleen, epigonal and Leydig organsHematopoiesis in spleen, epigonal and Leydig organs

–– Innate and learned immunityInnate and learned immunity


•• GI tractGI tract

–– Oral cavity, esophagus, stomach, intestine with Oral cavity, esophagus, stomach, intestine with

spiral valve, rectum, rectal gland, cloacaspiral valve, rectum, rectal gland, cloaca

•• Liver Liver

–– Two large lobes Two large lobes ±± gall bladdergall bladder

–– Rich in fatsRich in fats

•• Spleen + pancreasSpleen + pancreas


•• Urogenital systemUrogenital system

–– Male: Paired testes, deferent duct, claspersMale: Paired testes, deferent duct, claspers

–– Female: Paired ovaries, only one is active, oviduct + Female: Paired ovaries, only one is active, oviduct +

glands, bicornate uterus, cervixglands, bicornate uterus, cervix

–– Mating is extremely aggressiveMating is extremely aggressive

–– Various reproductive strategiesVarious reproductive strategies

•• Oviparous e.g., zebra sharks, skatesOviparous e.g., zebra sharks, skates

•• Ovoviviparous e.g., sting raysOvoviviparous e.g., sting rays

•• Viviparous e.g., hammerheadsViviparous e.g., hammerheads


•• MusculoskeletalMusculoskeletal

–– Cartilaginous skeletonCartilaginous skeleton

•• IntegumentIntegument

–– DenticlesDenticles

–– Fins: dorsals, pectoral, pelvic, anal, caudalFins: dorsals, pectoral, pelvic, anal, caudal


•• Sensory systemSensory system

–– VisionVision

–– Chemoreception: nares, tasteChemoreception: nares, taste

–– Vibration: inner ear, lateral lineVibration: inner ear, lateral line

–– Electroreception: ampullae of LorenziniElectroreception: ampullae of Lorenzini

–– Electric organs in electric raysElectric organs in electric rays

Now, for the waterNow, for the water……

•• Fish are completely dependent on the water forFish are completely dependent on the water for

–– OxygenOxygen

–– TemperatureTemperature

–– Waste excretion (HWaste excretion (H++, CO, CO22, N, N22))

–– Ionic balanceIonic balance

•• These can all be measured in the waterThese can all be measured in the water

•• Abrupt changes in these parameters are very Abrupt changes in these parameters are very

detrimentaldetrimental

Water parametersWater parameters

•• OxygenOxygen

–– Dissolved oxygen (DO) is provided by water flow, air Dissolved oxygen (DO) is provided by water flow, air

pumps and photosynthesispumps and photosynthesis

–– Measured using O2 metersMeasured using O2 meters

•• Should be > 6Should be > 6--15 ppm (mg/L) or > 90 %15 ppm (mg/L) or > 90 %

–– Assumed to be low withAssumed to be low with

•• Low water flowLow water flow

•• High tempsHigh temps

•• High organic loadHigh organic load


•• TemperatureTemperature

–– Ectotherms Ectotherms

–– Evolved to live within specific temp rangesEvolved to live within specific temp ranges

–– Temp affects Temp affects

•• Food intake + digestionFood intake + digestion

•• Immunity, pathogen load and drug PkImmunity, pathogen load and drug Pk

•• Water chemistry (DO, toxicities)Water chemistry (DO, toxicities)

–– Appropriate temp provided by heat exchangersAppropriate temp provided by heat exchangers


•• Waste excretionWaste excretion

–– Proteins are broken down to Proteins are broken down to toxic urea, NHtoxic urea, NH33 andand TMAOsTMAOs

–– Urea Urea

•• Stays in plasma at levels toxic to all other vertebratesStays in plasma at levels toxic to all other vertebrates

•• Commensal ureolytic bacteria (Commensal ureolytic bacteria (Clostridium Clostridium and and VibrioVibrio) in tissue ) in tissue

•• TMAOs in blood to protect proteinsTMAOs in blood to protect proteins

–– NHNH33

•• Excreted across the gills Excreted across the gills

•• Oxidized by bacteria in environmentOxidized by bacteria in environment

•• These essential bacteria are cultivated in These essential bacteria are cultivated in biological filtersbiological filters


FishFish Plants + algaePlants + algaebacteriabacteria

fungifungi

Nitrosomonas Nitrosomonas + ? + ? Nitrobacter Nitrobacter + ?+ ?

ureaurea NHNH33/NH/NH44++ NONO22

-- NONO33--

OO22 OO22

Ideal:Ideal: <0.02 ppm<0.02 ppm

Not:Not: >0.2 ppm>0.2 ppm

NHNH33, NO, NO22--, and NO, and NO33

22-- measured measured

using commercial assaysusing commercial assays

Tropical fish centre, UKTropical fish centre, UK



•• IonsIons

–– Salinity = all saltsSalinity = all salts

•• Most sp are marine (25Most sp are marine (25--35 ppt or g/L); some freshwater; some 35 ppt or g/L); some freshwater; some

euryhaline (bull sharks!)euryhaline (bull sharks!)

–– pH = pH = -- log [Hlog [H++]]

–– Alkalinity = anions (buffering capacity) e.g., HCOAlkalinity = anions (buffering capacity) e.g., HCO33--

–– Hardness = cations (essential minerals) e.g., CaHardness = cations (essential minerals) e.g., Ca2+2+, Mg, Mg2+2+

–– Measured using conductivity meters + commercial assaysMeasured using conductivity meters + commercial assays

So, onto the actual case...So, onto the actual case...

1. Signalment and history1. Signalment and history

•• Animals affected and other speciesAnimals affected and other species

•• System, water and diet informationSystem, water and diet information

2. Clinical exam2. Clinical exam

•• Observation of animals and environmentObservation of animals and environment

•• HandsHands--on exam where necessaryon exam where necessary

3. Further diagnostics3. Further diagnostics

4. Differential list4. Differential list

5. Treatment plan5. Treatment plan

HistoryHistory

•• Animals affectedAnimals affected

–– Species, size, date of acquisition, medical history, clinical Species, size, date of acquisition, medical history, clinical

signs, onset and progression (acute/chronic)signs, onset and progression (acute/chronic)

•• Other species in systemOther species in system

–– Fish, plants, invertebratesFish, plants, invertebrates

–– Most recent introductionsMost recent introductions

–– Biosecurity (cleaning, disinfection, vaccination, Biosecurity (cleaning, disinfection, vaccination,

quarantine)quarantine)

HistoryHistory

•• System informationSystem information

–– Type (open, flowType (open, flow--through, closed)through, closed)

–– SizeSize

–– Time in operationTime in operation

–– ‘‘Life supportLife support’’ -- these ALL require maintenancethese ALL require maintenance

•• Air pumps, water pumpsAir pumps, water pumps

•• Mechanical filters e.g., protein skimmers, sand filtersMechanical filters e.g., protein skimmers, sand filters

•• Biological filters e.g., canister Biological filters e.g., canister

•• Chemical and other filters e.g., ozone, UV sterilizersChemical and other filters e.g., ozone, UV sterilizers

•• Heaters/chillersHeaters/chillers

•• LightsLights

HistoryHistory

•• WaterWater

–– Source (tapSource (tap--water, sea water)water, sea water)

–– Additions (conditioners, salts, meds), contaminantsAdditions (conditioners, salts, meds), contaminants

–– Water turnover (volume + frequency of changes)Water turnover (volume + frequency of changes)

–– Water parameters (target + actual)Water parameters (target + actual)

•• TemperatureTemperature

•• Dissolved oxygenDissolved oxygen

•• SalinitySalinity

•• pHpH

•• NHNH33, NO, NO22--, NO, NO33

22--

•• Alkalinity, hardnessAlkalinity, hardness

•• CuCu2+2+, Zn, Zn2+2+

HistoryHistory

•• DietDiet–– Food fed (historic and recent)Food fed (historic and recent)

–– Frequency and weightFrequency and weight

–– Storage and thawingStorage and thawing

–– Supplements (MUST add vit B1, C, E, iodide)Supplements (MUST add vit B1, C, E, iodide)

•• Dietary deficiencies are very commonDietary deficiencies are very common

•• Food intake is essential for hydrationFood intake is essential for hydration

Clinical exam Clinical exam -- observationobservation

•• Observation of the animalsObservation of the animals

–– Alertness, responsiveness (Alertness, responsiveness (‘‘BARBAR’’))

–– VentilationVentilation

–– Swimming behavior and positionSwimming behavior and position

–– Body conditionBody condition

–– External lesionsExternal lesions

•• Eyes, mouth, skin, fins and claspers, cloacaEyes, mouth, skin, fins and claspers, cloaca

•• Always compare to the species normalsAlways compare to the species normals

Clinical exam Clinical exam -- observationobservation

•• Observation of the environment Observation of the environment

–– Tank and dTank and déécor cor

–– Tank matesTank mates

–– Life support systemsLife support systems

–– WaterWater

•• Are these all suitable? Are these all suitable?

•• Aggression, trauma and poor water quality are Aggression, trauma and poor water quality are

extremely commonextremely common

Clinical exam Clinical exam -- restraintrestraint

•• First, do you really need to get hands on?First, do you really need to get hands on?–– Risk of traumaRisk of trauma

–– Risk of acidosisRisk of acidosis

•• Second, do you need manual or chemical restraint?Second, do you need manual or chemical restraint?–– Manual: Manual:

•• Sufficient personnelSufficient personnel

•• Calm species (Calm species (‘‘tonic immobilitytonic immobility’’ in VD recumbency)in VD recumbency)

•• NonNon--invasiveinvasive

–– Chemical: Chemical: •• Fractious species (e.g., reef sharks, pelagic rays)Fractious species (e.g., reef sharks, pelagic rays)

•• Invasive procedureInvasive procedure

Clinical exam Clinical exam -- restraintrestraint

Some general principals:Some general principals:

•• ALWAYS have all the equipment readyALWAYS have all the equipment ready

•• Use original source water Use original source water

•• Keep the gills and skin wet Keep the gills and skin wet

•• Consider temp, NH3, DOConsider temp, NH3, DO–– Aerate wellAerate well

–– Obligate ram ventilatorsObligate ram ventilators

–– Monitor if procedure is longMonitor if procedure is long

Clinical exam Clinical exam -- manual restraintmanual restraint

Some hazards!Some hazards!

Cut the spines fromCut the spines fromstingraysstingrays

Hold sharks + sawfish behind Hold sharks + sawfish behind the head (avoiding gill slits)the head (avoiding gill slits)

Clinical exam Clinical exam -- chemical restraintchemical restraint

•• MSMS--222 bath (tricaine methane sulfonate, Finquel)222 bath (tricaine methane sulfonate, Finquel)

–– 4040--50 ppm or mg/L for sedation50 ppm or mg/L for sedation

–– Up to 100 ppm for anesthesiaUp to 100 ppm for anesthesia

–– Licensed in fin fish in US + UK, not CanadaLicensed in fin fish in US + UK, not Canada

–– Wear glovesWear gloves

•• Eugenol (in clove oil) bathEugenol (in clove oil) bath

•• Propofol IV or ICePropofol IV or ICe

•• Ketamine Ketamine ±± medetomidine or xylazine IM medetomidine or xylazine IM

Clinical exam Clinical exam -- chemical restraintchemical restraint

•• Stages of anesthesiaStages of anesthesia–– Early: Ataxia, excitementEarly: Ataxia, excitement

–– Surgical: Loss of responses, slow and shallow respsSurgical: Loss of responses, slow and shallow resps

–– Excessive depth: Loss of resps, cardiovascular collapse Excessive depth: Loss of resps, cardiovascular collapse

•• MonitorMonitor–– Aeration (flow of water, gilling rate, gill color)Aeration (flow of water, gilling rate, gill color)

–– Heart rate (Doppler or BHeart rate (Doppler or B--mode US)mode US)

–– TemperatureTemperature

•• Allow full recovery before reAllow full recovery before re--introducing tank matesintroducing tank mates

Clinical examClinical exam

•• Clinical examClinical exam

–– Examine eyes, nares, oral cavity, spiracles, gill slitsExamine eyes, nares, oral cavity, spiracles, gill slits

–– Examine entire skin surfaceExamine entire skin surface

–– Examine claspers, cloaca Examine claspers, cloaca

–– Palpate coelom, M/S systemPalpate coelom, M/S system

DiagnosticsDiagnostics

•• The list...The list...

–– MorphometricsMorphometrics

–– Skin scrapesSkin scrapes

–– Fecal analysisFecal analysis

–– Diagnostic imagingDiagnostic imaging

–– Biopsies/aspiratesBiopsies/aspirates

•• Gills, massesGills, masses

–– Blood samplingBlood sampling

–– NecropsyNecropsy

MorphometricsMorphometrics

•• Always obtain a weight Always obtain a weight

•• Sharks Sharks

–– Total lengthTotal length

–– Precaudal lengthPrecaudal length

–– Clasper lengthClasper length

•• Batoids Batoids

–– Disc widthDisc width

–– Clasper lengthClasper length

Skin scrapesSkin scrapes

•• MethodMethod

–– Use scalpel bladeUse scalpel blade

–– Add drop of tank water and a coverslipAdd drop of tank water and a coverslip

–– Examine under direct microscopy ASAP at x40Examine under direct microscopy ASAP at x40--400400

•• Abnormalities include monogene trematodes Abnormalities include monogene trematodes

(flukes) e.g., (flukes) e.g., Dermopthirius Dermopthirius and and DermophthiodesDermophthiodes

Fecal analysisFecal analysis

•• MethodMethod–– Obtain by cloacal washObtain by cloacal wash

–– Direct, float, DifDirect, float, Dif--Quik stain, Gram stainQuik stain, Gram stain

•• Abnormalities include Abnormalities include –– CoccidiaCoccidia

–– NematodesNematodes

–– TrematodesTrematodes

–– CestodesCestodes

–– White blood cellsWhite blood cells

–– Significant Gram positive floraSignificant Gram positive flora

Diagnostic imagingDiagnostic imaging

•• UltrasonographyUltrasonography

–– Excellent soft tissue detail (cardiac, GIT, liver and gall Excellent soft tissue detail (cardiac, GIT, liver and gall

bladder, pancreas, spleen, UG tract)bladder, pancreas, spleen, UG tract)

–– Good for dystocia, pyometra, neoplasia, goiterGood for dystocia, pyometra, neoplasia, goiter

Diagnostic imagingDiagnostic imaging

•• RadiographyRadiography

–– Good cartilage detail and gaseous detail (e.g., Good cartilage detail and gaseous detail (e.g.,

necrotic pups)necrotic pups)

–– Contrast studies provide good GIT detailContrast studies provide good GIT detail

Tissue samplingTissue sampling

•• Biopsies/aspirates/endoscopyBiopsies/aspirates/endoscopy

–– Biopsy gill filamentsBiopsy gill filaments

–– Aspirate or biopsy any masses or fluid accumulationsAspirate or biopsy any masses or fluid accumulations•• CytologiesCytologies

•• Fluid analysisFluid analysis

•• CulturesCultures

•• HistologyHistology

•• Viral isolationViral isolation

•• Electron microscopyElectron microscopy

Blood samplingBlood sampling

•• AnticoagulantsAnticoagulants

–– Sharks Sharks

•• Dry EDTA preferableDry EDTA preferable

•• Dry heparinDry heparin

–– BatoidsBatoids

•• Dry heparin preferableDry heparin preferable

Remember these blood cells are fragile Remember these blood cells are fragile

and the plasma is very concentratedand the plasma is very concentrated

Venipuncture sites Venipuncture sites –– all speciesall species

•• Ventral tail veinVentral tail vein

–– MUST be midlineMUST be midline

Venipuncture sites Venipuncture sites -- sharkssharks

•• Posterior cardinal veinsPosterior cardinal veins

–– Caudolateral to either dorsal finCaudolateral to either dorsal fin

Blood sample processingBlood sample processing

1.1. Blood cultureBlood culture

2.2. Blood smearsBlood smears•• Wright or DifWright or Dif--Quik for differentialQuik for differential

•• Gram stain for bacteria Gram stain for bacteria

3.3. PCV, TS, iPCV, TS, i--STATSTAT

4.4. Total cell countsTotal cell counts•• Modified NattModified Natt--HerrickHerrick (Old 2006, Arnold 2005) (Old 2006, Arnold 2005)

5. 5. Plasma/serum separatedPlasma/serum separated•• Allow 2Allow 2--4hrs to clot4hrs to clot

•• Dilute for BUN, Na, ClDilute for BUN, Na, Cl

Whole blood will not survive overnightWhole blood will not survive overnight

Blood cellsBlood cells

•• Red blood cellsRed blood cells

–– Large (2.5x mammals) and nucleatedLarge (2.5x mammals) and nucleated

–– Immature forms common Immature forms common

–– HCT lower than mammalsHCT lower than mammals

–– RBC very unreliableRBC very unreliable

•• ThrombocytesThrombocytes

–– Some species have 2 typesSome species have 2 types

White blood cellsWhite blood cells

•• WBC count >> mammals, up to 40,000/mmWBC count >> mammals, up to 40,000/mm33

•• Leukocyte nomenclature very confusingLeukocyte nomenclature very confusing

–– Species differencesSpecies differences

–– Different stages of cell maturityDifferent stages of cell maturity

White blood cellsWhite blood cells

•• Lymphocytes Lymphocytes •• Most common cell typeMost common cell type

•• Coarse eosinophilic granulocytes (CEG) Coarse eosinophilic granulocytes (CEG) •• Major phagocytesMajor phagocytes

•• Fine eosinophilic granulocytes (FEG) Fine eosinophilic granulocytes (FEG) •• Have been called heterophilsHave been called heterophils

•• Neutrophils Neutrophils

•• Monocytes Monocytes

•• Basophils Basophils •• Common in rays onlyCommon in rays only

1000x

ChemistriesChemistries

•• Plasma osmolality Plasma osmolality •• 800800--1100 mOsm/kg1100 mOsm/kg

•• Proteins Proteins •• TS by refractometer ~ 2 x TP by colorimetric assay TS by refractometer ~ 2 x TP by colorimetric assay

•• Albumin very lowAlbumin very low

•• Glucose Glucose •• Lower than other vertebratesLower than other vertebrates

•• Tissue enzymes vary by speciesTissue enzymes vary by species

•• pH ~7pH ~7•• Acidosis commonAcidosis common

EuthanasiaEuthanasia

•• Recommended (AVMA, 2006)Recommended (AVMA, 2006)–– MSMS--222 bath, >500 mg/L for 15mins following loss of 222 bath, >500 mg/L for 15mins following loss of gillinggilling

–– Sedation followed by pentobarbital IV or intracardiac, Sedation followed by pentobarbital IV or intracardiac, >100 mg/kg>100 mg/kg

–– Cranial concussion, decapitation then pithingCranial concussion, decapitation then pithing

•• NOT approvedNOT approved–– Eugenol (clove oil)Eugenol (clove oil)

–– Cooling/freezingCooling/freezing

–– AsphyxiationAsphyxiation

NecropsyNecropsy

•• Must be SOONMust be SOON

•• Plan samples before startingPlan samples before starting

–– Cultures (bacterial, fungal, VI)Cultures (bacterial, fungal, VI)

•• Liver + CSF Liver + CSF

–– Squash prepsSquash preps

–– Stained impression smears (DQ, GS)Stained impression smears (DQ, GS)

–– FormalinFormalin--fixed and frozen tissue fixed and frozen tissue

Necropsy Necropsy -- sharkshark

Necropsy Necropsy -- batoidbatoid

Necropsy Necropsy –– ‘‘squash prepssquash preps’’

•• Sample sites: gills, skin, fin, liver, spleen, Sample sites: gills, skin, fin, liver, spleen,

kidney, gonads, GIT, lesionskidney, gonads, GIT, lesions

•• Method: Method:

–– Take a small 1Take a small 1--2mm diameter section2mm diameter section

–– Squash under a coverslip with a drop of salineSquash under a coverslip with a drop of saline

–– Examine at x40Examine at x40--x100x100


•• Abnormalities Abnormalities -- infectious agents:infectious agents:

–– FungiFungi

–– Bacteria (shape and motility)Bacteria (shape and motility)

–– ‘‘SporozoaSporozoa’’, protozoa, protozoa

–– NematodesNematodes

–– TrematodesTrematodes

–– AcanthocephalansAcanthocephalans

–– PentasomidsPentasomids


•• Abnormalities:Abnormalities:

–– GranulomasGranulomas

–– Increased melanomacrophage centers Increased melanomacrophage centers

(chronic stress)(chronic stress)

–– Increased WBCIncreased WBC

•• Also used to identify tissues and Also used to identify tissues and

confirm tissue architecture and sexconfirm tissue architecture and sex

Necropsy Necropsy –– impression smearsimpression smears

•• Sample sites: liver, spleen, kidney, gall bladder, Sample sites: liver, spleen, kidney, gall bladder,

lesionslesions

•• Methods:Methods:

–– Take a small 2mm sectionTake a small 2mm section

–– Dab on tissueDab on tissue

–– Make 2Make 2--3 touch impressions3 touch impressions

–– Gram stain, DifGram stain, Dif--Quik, modified acidQuik, modified acid--fast, PASfast, PAS

Necropsy Necropsy –– impression smearsimpression smears

•• Abnormalities:Abnormalities:

–– FungiFungi

–– Bacteria (size, shape, stain, group)Bacteria (size, shape, stain, group)

–– ‘‘SporozoaSporozoa’’, protozoa, protozoa

–– White blood cellsWhite blood cells

–– Hyperplastic/neoplastic cellsHyperplastic/neoplastic cells

Necropsy Necropsy –– other samplesother samples

•• Histopath Histopath

–– FormalinFormalin--fixed (10% NBF), Bouinfixed (10% NBF), Bouin’’s, Davidsons, Davidson’’s, alcohols, alcohol

–– H+E, GS, AFH+E, GS, AF

–– Where? NW Zoo path, U ConneticutWhere? NW Zoo path, U Conneticut

•• Structural testsStructural tests

–– SEM, TEMSEM, TEM

•• Antibody testsAntibody tests

–– ELISA ELISA

–– IFAIFA

–– Virus neutralizationVirus neutralization

•• DNA testsDNA tests

–– PCR PCR

–– SequencingSequencing

•• ToxicologyToxicology

SummarySummary

•• Elasmobranch health is completely dependent on the Elasmobranch health is completely dependent on the environment, water and diet that is providedenvironment, water and diet that is provided

•• Trauma, poor water quality and dietary deficiencies are Trauma, poor water quality and dietary deficiencies are common, and can be determined from a thorough history common, and can be determined from a thorough history and observationand observation

•• HandsHands--on diagnostics are possible in most clinical settingson diagnostics are possible in most clinical settings

•• Where further diagnostics are required, normal values Where further diagnostics are required, normal values from a conspecific are usefulfrom a conspecific are useful

For more infoFor more info……

•• BooksBooks–– Fish medicine (Stoskopf)Fish medicine (Stoskopf)

–– Fish disease (Noga)Fish disease (Noga)

–– Elasmobranch husbandry manual (Smith)Elasmobranch husbandry manual (Smith)

–– BSAVA manual of ornamental fish (Wildgoose)BSAVA manual of ornamental fish (Wildgoose)

•• JournalsJournals–– Diseases of aquatic organismsDiseases of aquatic organisms

–– Vet clinics of north AmericaVet clinics of north America

–– Exotic pet medicineExotic pet medicine

–– Journal of zoo and wildlife medicineJournal of zoo and wildlife medicine

–– Journal of aquatic animal healthJournal of aquatic animal health

•• ConferencesConferences–– Eastern fish health workshopEastern fish health workshop

–– International association of aquatic animal medicineInternational association of aquatic animal medicine

•• CoursesCourses–– Aquavet and others (Cornell, Penn, Florida, Davis, N Carolina)Aquavet and others (Cornell, Penn, Florida, Davis, N Carolina)

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