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O R I G I N A L R E S E A R C H

Hematology, leukocyte cytochemical analysis, plasmabiochemistry, and plasma electrophoresis of wild-caught andcaptive-bred Gila monsters (Heloderma suspectum )

Kerri Cooper-Bailey1, Stephen A. Smith1, Kurt Zimmerman1, Rosalie Lane2, Rose E. Raskin3, Dale DeNardo4

1Department of Biomedical Sciences and Pathobiology, Virginia–Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and

State University, Blacksburg, VA, USA; 2Avian and Exotic Animal Clinical Pathology Laboratory, Wilmington, OH, USA; 3Department of Comparative

Pathobiology, School of Veterinary Medicine, Purdue University, West Lafayette, IN, USA; and 4School of Life Sciences, Arizona State University, Tempe,

AZ, USA

Key Words

Blood values, CBC, cytochemistry,

hemoparasites, lizard

Correspondence

Stephen A. Smith, Department of Biomedical

Sciences and Pathobiology, Virginia–Maryland

Regional College of Veterinary Medicine,

Virginia Polytechnic Institute and State

University, Duck Pond Drive, Phase II,

Blacksburg, VA 24061-0442, USA

E-mail: [email protected]

DOI:10.1111/j.1939-165X.2011.00337.x

Background: The Gila monster (Heloderma suspectum), one of several ven-

omous lizard species in the world, is found within the United States and

Mexico and is recognized as an iconic symbol of the American Southwest.

Thus, Gila monsters are of growing interest in the captive reptile trade and

within zoological and educational institutions.

Objectives: The aims of this study were to determine results for CBCs,

describe cytochemical reactions in WBCs, and obtain plasma biochemical and

protein electrophoresis results from wild-caught and captive-bred H. suspectum.

Methods: Ventral tail vein blood samples were obtained from 16 captive

(14 wild-caught and 2 captive-bred) Gila monsters. CBCs, RBC morpho-

metric analysis, plasma biochemical analysis, and protein electrophoresis

were performed. Leukocytes were stained for peroxidase, Sudan black B

(SBB), chloroacetate esterase, napthyl butyrate esterase, and leukocyte

alkaline phosphatase, and blood smears were examined for the presence of

hemoparasites.

Results: The median (range) PCV was 37% (22–50%) and WBC count was

4.6� 103/mL (3.3–6.4� 103/mL) with approximately 50% heterophils and

fewer lymphocytes, basophils, azurophils, and monocytes in decreasing

order. Cytochemical reactions were unique among reptiles with strong

staining for peroxidase and SBB in monocytes/azurophils. Biochemical

results were similar to those of earlier reports with slight increases in uric

acid and urea concentrations. Plasma electrophoretic results indicated that

albumin was approximately equal to the combined globulin fractions.

Conclusions: Results of blood analysis in healthy wild-caught and captive-

bred H. suspectum may be useful for monitoring health status in this species.

Introduction

The Gila monster, Heloderma suspectum, is one of several

species of venomous lizards in the world.1 Its distribu-

tion is tightly linked to the Sonoran Desert located

within Arizona and the state of Sonora, Mexico, and its

range also extends to extreme eastern California,

southern Nevada, southern Utah, and western New

Mexico.2–5 Growing interest in this species in the

pet trade and research arena has made acquisition of

baseline hematologic and biochemical values for these

animals relevant.

Materials and Methods

Animals and sample collection

Sixteen captive, clinically healthy adult Gila monsters

were used in this study. The animals had normal

behavior and water and food intake, and abnormali-

ties were not detected on physical examination. Four-

teen of the animals were wild-caught and comprised

11 males and 3 females captured in Arizona and main-

tained by one of the authors (D.D.); 2 were captive-

bred and were males owned by another author

316 Vet Clin Pathol 40/3 (2011) 316–323 c�2011 American Society for Veterinary Clinical Pathology

Veterinary Clinical Pathology ISSN 0275-6382

mailto:[email protected]

(K.C.B.). Using manual restraint, approximately 1 mL

of blood was obtained from the ventral tail vein of each

animal using a 23 G needle and 1 mL syringe. Each

sample was divided 3 ways: one drop was used to pre-

pare 2 direct blood smears that were allowed to air dry

and 0.4–0.5 mL were placed in both a lithium heparin

and EDTA tube (Microtainer, Becton Dickinson,

Franklin Lakes, NJ, USA). Plasma was collected from

the lithium heparin samples within 10 minutes of col-

lection following centrifugation at 1400g for 5 min-

utes. Plasma was then transferred to individual 1.5 mL

microcentrifuge tubes (SealRite, USA Scientific Inc.,

Ocala, FL, USA). EDTA samples were thoroughly

mixed by inversion. One blood smear and the plasma

and EDTA samples were sent by overnight courier to a

commercial diagnostic laboratory (Avian and Exotic

Animal Clinical Pathology Laboratories, Wilmington,

OH, USA) within 12–24 hours after collection.

Sample analysis

Samples were processed immediately upon receipt,

and a complete ‘‘reptile analysis,’’ including a CBC,

plasma biochemical analysis, and plasma electropho-

resis, was performed. PCV was determined by centrif-

ugation of the EDTA sample using a microhematocrit

centrifuge, and the buffy coat was examined for

microfilaria under low magnification (�100) on a glass

slide. Hemoglobin concentration was determined by

an automated procedure using a hemoglobinometer

(Coulter Electronics, Hialeah, FL, USA). Erythrocyte

counts were performed manually using a hemocyto-

meter (American Optical, Scientific Instrument Divi-

sion, Buffalo, NY, USA), and WBC counts were

performed by the direct method with Natt and Her-

rick’s solution.6 Blood smears were stained with

Wright–Giemsa stain (Wescor 7120 Aerospray Hema-

tology Stainer, Wescor Inc., Logan, UT, USA). A mini-

mum of 100 sequential WBCs were counted from each

sample for determination of leukocyte differential val-

ues. All differential counts were performed by the

same individual (R.L.) and then reviewed by a second

individual (medical technician trained in reptilian

blood evaluation). For wild-caught animals (n = 14),

erythrocyte morphologic and morphometric charac-

teristics (total cell area, area of the nucleus, cell length,

and width) were determined for cells in 10 random

fields on the Wright–Giemsa stained smears (K.Z.)

using a combination of software programs (ImageJ, NIH,

Bethesda, MD, USA; NIS Elements Laboratory Imaging

Software, Nikon Instruments Inc., Melville, NY, USA).7

Cytochemical analysis of WBCs for peroxidase,

chloroacetate esterase (CAE), naphthyl butyrate est-

erase (NBE), Sudan black B (SBB), and leukocyte

alkaline phosphatase (LAP) staining was qualitatively

assessed (R.E.R.) on blood smears from each animal

(n = 16) using standard cytochemical techniques.8–14

Immunocytochemical analysis for expression of B lym-

phocyte antigen (BLA.36, mouse monoclonal anti-

body, Novacastra, New Castle Upon Tyne, UK), CD3

(rabbit polyclonal antibody, Dako, Carpinteria, CA,

USA), and CD79a (mouse monoclonal antibody, Dako)

was also performed using additional blood smears;

however, these reagents have not been validated for

use in this species, and immunoreactivity was negative

in all cells (data not shown).

Plasma biochemical analysis was performed using

an automated chemistry analyzer (Cobas, Roche Diag-

nostics Limited, West Sussex, England, UK). Plasma in

a volume of 10 mL was analyzed by agarose gel electro-

phoresis using a semi-automated Sebia Hydrasys sys-

tem (Sebia Inc., Norcross, GA, USA).

Statistical analysis

Numeric data from the CBC, plasma biochemical, and

electrophoretic data were analyzed for normality and

descriptive statistics determined using commercial sta-

tistical software (Minitab 15, Minitab Inc., State Col-

lege, PA, USA).

Results

The CBC (Table 1) and RBC morphometric data

(Table 2) for all 16 Gila monsters and 14 wild-caught

animals, respectively, were normally distributed ex-

cept for WBC counts and absolute heterophil and

azurophil counts. PCVs ranged from 22% to 50%.

Erythrocytes were oval, measured approximately

18� 11 mm, had a typical orange cytoplasm, and had

central, round, homogenous, pale basophilic nuclei

(Figure 1A). Slight anisocytosis and polychromasia

were noted among the erythrocytes. Five different leu-

kocyte types were noted in this study: heterophils,

lymphocytes, basophils, azurophils, and monocytes

(Figure 1B–F) in order of decreasing number. Eosino-

phils were not identified in any of the samples. He-

terophils measured approximately 12 mm in diameter,

contained numerous, distinct, oval to sharp-pointed,

red-orange, cytoplasmic granules, and an oval, lightly

basophilic eccentric nucleus (Figure 1B). The median

heterophil percentage was 45% with several individu-

als, irrespective of the presence of hemoparasites, hav-

ing 4 50% heterophils. Most of the lymphocytes were

large lymphocytes, measuring approximately 7 mm in

diameter. These cells were round and slightly larger

Vet Clin Pathol 40/3 (2011) 316–323 c�2011 American Society for Veterinary Clinical Pathology 317

Cooper-Bailey et al Hematology and biochemistry of Gila monsters

than thrombocytes, contained round nuclei with

smudged chromatin, and had a faint rim of basophilic

cytoplasm (Figure 1C). Basophils were distinct with

their numerous dark purple granules partially obscuring

an oval eccentric nucleus and measured approximately

10mm in diameter (Figure 1D). Azurophils measured

approximately 10mm in diameter, contained faint azur-

ophilic granules with blue-grey cytoplasm, which lacked

vacuoles, and had slightly indented basophilic nuclei

(Figure 1E). Monocytes were similar to azurophils in

size, color, and nuclear shape, with the only difference

being the lack of azurophilic granules (Figure 1F).

Thrombocytes were approximately 5mm in diameter

and round with dark, basophilic, homogenous nuclei,

and scant cytoplasm ranging from almost colorless to

pale grey-blue containing a few indistinct vacuoles

and basophilic granules (Figure 1G). Platelet numbers

were not evaluated. Four of the animals were parasitized

with an unidentified filarial parasite (Figure 1H).

Leukocytes had variable staining patterns for per-

oxidase, SBB, CAE, and NBE (Table 3, Figure 2).

Heterophils and azurophils/monocytes had similar

positive staining for peroxidase and SBB. In hetero-

phils peroxidase staining was weak and granular. In

monocytes SBB staining was stronger and more glob-

ular. Basophils had trace positivity for SBB between

granules, which were negative. Lymphocytes and

thrombocytes did not stain with any of the cytochem-

ical stains tested except for rare focal positivity for CAE

in lymphocytes. Heterophils stained for both CAE and

NBE between the granules, and the cytoplasm of

azurophils/monocytes stained diffusely. None of the

leukocytes stained for LAP (Table 3).

Plasma biochemical (Table 4) and protein electro-

phoretic (Table 5) profiles were determined. Data for

biochemical analytes were normally distributed except

for phosphorus and bile acid concentrations and crea-

tine kinase activity. For plasma electrophoretic values

only albumin and b-fractions were normally distrib-

uted. A representative electrophoretic tracing from

one of the study animals was compared with a tracing

from an animal (outside the study) with leukocytosis

resulting from retained eggs (Figure 3). The tracing

from the ill animal showed a relative increase in the a-,

b-, and g-globulin fractions as well as increased bridg-

ing of the b–g region.

Discussion

Baseline values for wild populations of threatened or

endangered species are valuable for reference in

Table 2. Morphometric analysis of erythrocytes from 14 wild-caught Gila monsters (Heloderma suspectum).

Measurement Mean SD Minimum Q1 Median Q3 Maximum

Total area (mm2) 150.57 21.20 103.77 136.45 149.13 164.03 197.35

Area of nucleus (mm2) 22.40 3.24 15.00 19.98 22.32 24.82 31.54

Length (mm) 17.83 1.30 14.80 16.97 17.86 18.72 21.77

Width (mm) 10.57 1.05 7.61 9.93 10.57 11.33 13.08

Q, quartile.

Table 1. Hematologic data from 16 Gila monsters (Heloderma suspectum).

Variable Mean SD Minimum Q1 Median Q3 Maximum

RBC (� 106/mL) 0.50 0.13 0.22 0.42 0.53 0.61 0.67

PCV (%) 37 8 22 32 37 44 50

Hemoglobin (g/dL) 7.4 0.9 6.0 6.5 7.5 8.0 9.5

MCV (fL) 812 370 415 537 648 978 1773

MCHC (g/dL) 20.9 5.3 14.0 17.0 21.0 23.0 36.0

WBC (� 103/mL)� 4.72 0.84 3.30 4.20 4.60 5.20 6.40

Heterophils (� 103/mL)� 2.17 0.61 1.35 1.69 2.08 2.57 3.31

Lymphocytes (� 103/mL) 1.54 0.80 0.58 0.73 1.61 2.01 3.39

Basophils (� 103/mL) 0.57 0.23 0.21 0.44 0.54 0.64 1.05

Azurophils (� 103/mL)� 0.38 0.27 0.00 0.14 0.38 0.47 1.14

Monocytes (� 103/mL) 0.07 0.08 0.00 0.00 0.00 0.16 0.19

Eosinophils (� 103/mL) 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Total solids (g/dL) 6.3 1.0 5.0 5.5 6.0 7.0 8.4

�Distribution of data not normal.

Q, quartile.


Cooper-Bailey et alHematology and biochemistry of Gila monsters

captive health and conservation programs. In addition,

with growing interest in the Gila monster as an orna-

mental, educational, and scientific study animal, base-

line values for captive individuals are needed for the

veterinary community and its work with exotic spe-

cies.11,15–18 Variations due to availability of resources,

diet, climatic changes, and activity are often found

between captive and wild populations of reptiles; this

trend was also suggested by our results. Further anal-

ysis of the data (not shown owing to low numbers of

animals in groups) also suggested a possible influence

of wild-caught versus captive-bred status on hemato-

logic, biochemical, and protein electrophoretic data;

the need for independent reference intervals should be

considered.

Quantitative and morphologic characteristics of

blood cells are important in the assessment of reptilian

health, but may vary among species.19–24 In a previous

study, erythrocytes and leukocytes of the Mexican

beaded lizard, Heloderma horridum, the sister species of

the Gila monster, were described and served as a guide

for the current study.22 PCVs from this study were in

agreement with those reported as normal for reptiles,

20–40%.21,25,26 For leukocyctes, heterophils were

most numerous. It has been reported that heterophil

percentages can be as high as 40% of the overall leu-

kocyte count for some normal reptilian species.21,25,27

In this study, Gila monsters had a higher median he-

terophil percentage than is typical of other

reptiles. The next most common leukocyte type was

Figure 1. Blood from a wild-caught captive Gila monster (Heloderma suspectum). Modified-Wright’s stain, bars = 10 mm. (A) Erythrocyte with hemoglo-

binized cytoplasm, elliptical shape, and oval central basophilic nucleus. (B) Heterophil with numerous distinct oval to pointed red-orange granules and a

basophilic oval eccentric nucleus. (C) Lymphocyte with a round nucleus, smudged chromatin, and faint basophilic cytoplasm. (D) Basophil with dark

purple granules obscuring an oval eccentric nucleus. (E) Azurophil with faint azurophilic granules, blue-grey cytoplasm lacking vacuoles, and a reniform

basophilic nucleus. (F) Monocyte with a nucleus similar to that of the azurophil, but with slightly more basophilic cytoplasm and lacking azurophilic

granules. (G) Thrombocyte with a round dense homogenous nucleus and scant colorless to pale grey-blue cytoplasm with a few indistinct vacuoles. (H)

Unidentified filarial parasite seen in 4 blood samples; larva were approximately 200� 8 mm with a pointed anterior end and a rounded posterior end, no

apparent body cavity, and numerous 2-3 mm oval dark basophilic nuclei.

Table 3. Cytochemical staining reactions of WBCs from Gila monsters (Heloderma suspectum).

Stain/reaction Heterophil Lymphocyte Basophil Azurophil/monocyte Thrombocyte

Peroxidase 1 (Granular) - - 11 (Granular) -

SBB 1 (Diffuse) - 1 � 111 (Granular) -

CAE 1 1 (Rare focal) - 11 (Diffuse) -

NBE 1 - - 11 (Diffuse) -

LAP - - - - -

SBB, Sudan black B; CAE, chloroacetate esterase; NBE, naphthyl butyrate esterase; LAP, leukocyte alkaline phosphatase; � , negative; 1, weakly pos-

itive; 11, moderately positive; 111, strongly positive; �, intergranular reaction.



Figure 2. Blood from Gila monsters (Heloderma suspectum) stained for chloroacetate esterase (A, B), peroxidase (C, D), naphthyl butyrate esterase (E,

F), and Sudan black B (G–I). h, heterophil; m, monocyte/azurophil; b, basophil; l, lymphocyte; t, thrombocyte. See text for details.

Table 4. Plasma biochemical data from 16 Gila monsters (Heloderma suspectum).

Analyte� Mean SD Minimum Q1 Median Q3 Maximum

Total protein (g/dL) 6.3 0.5 5.4 6.1 6.3 6.6 6.9

Glucose (mg/dL) 48.3 24.2 4.0 36.3 48.0 58.5 109.0

Phosphorus (mg/dL) 3.4 1.8 1.1 2.3 2.8 4.0 8.60

Sodium (mmol/L) 144 3 140 141 143 147 151

Potassium (mmol/L)w 3.9 0.5 2.8 3.5 4.0 4.230 4.6

Ionized calcium (mmol/L) 1.26 0.10 1.09 1.19 1.23 1.32 1.50

pH 7.66 0.09 7.48 7.60 7.67 7.74 7.79

Total calcium (mg/dL) 12.2 0.8 10.2 11.7 12.2 13.0 13.4

Creatine kinase (U/L)w 600 457 144 253 464 830 1812

Aspartate aminotransferase (U/L) 42 13 20 30 42 51 66

Bile acids (mmol/L)w 16.2 13.3 2.6 7.0 12.4 21.7 55.1

Urea (mg/dL) 15 6 6 13 14 17 30

Uric acid (mg/dL) 16.8 4.2 9.8 14.1 17.2 19.0 24.7

�Total protein measured by biuret reaction; glucose, hexokinase; phosphorus, phosphomolybdate-UV; sodium, potassium, ionized calcium, pH, direct

undiluted measurement by ion selective electrodes; total calcium, arsenazo III dye; creatine kinase, UV-kinetic; aspartate aminotrasferase, IFCC UV-

kinetic; bile acids, 3a-HSD; and urea and uric acid, kinetic spectrophotmetry.wDistribution of data not normal.

Q, quartile.



lymphocytes. Although both small and large lympho-

cytes have been reported from various species of rep-

tiles, the majority of the lymphocytes observed in this

study were large. The wide range in lymphocyte per-

centages is common in many species of reptiles and

thus was considered normal.15,21,22,25 Basophils, the

next most common leukocyte, were similar in percent-

age to those described for other reptiles.20,21,26 The low

percentages of azurophils and monocytes and absence

of eosinophils in these study animals are in agreement

with reports in the reptilian literature.21,25

Heterophils from chelonians (turtles and tortoises)

and crocodilians (alligators, caimans, and crocodiles)

have been uniformly reported as being peroxidase-

negative.9,12,28,29 Similarly, heterophils and azurophils

from some Squamata (lizards and snakes, eg, the east-

ern diamondback rattlesnake, Crotalus adamanteus)

have also been reported as being peroxidase-negative,

whereas heterophils and azurophils from other squa-

mates, eg, the green iguana, Iguana iguana, have been

reported as being peroxidase-positive.8,11,12,28,30,31 In

this study, both heterophils and azurophils of the Gila

monster demonstrated varying degrees of peroxidase

staining in the cytoplasm. However, staining in azuro-

phils/monocytes was much stronger than in heterophils,

which is in contrast to reports in other lizards in which

peroxidase staining was negative in azurophils.11 SBB

staining was also distinct in our study animals as

azurophils/monocytes were strongly positive and

heterophils were weakly positive. In green iguanas,

heterophils were found to be strongly positive for SBB

and azurophil/monocytes were negative.11 Also unique

among most species of reptiles was the positive cyto-

plasmic staining by SBB within the basophils of Gila

monsters.8,10,11,21,28 In addition, in contrast to reports in

green iguanas where both heterophils and azurophils

were found to be CAE negative, in this study CAE pos-

itivity was seen in both heterophils and azuruphils, as

well as in some lymphocytes with focal staining.11

Most biochemical values were consistent with those

reported for the congeneric Mexican beaded lizard, as

well as with those reported for other reptilian spe-

cies.22,23,25 The only noteworthy differences between

the 2 species of Heloderma were the plasma urea and uric

acid concentrations, which were higher for the Gila

monsters in this study.22 High concentrations of these

analytes may suggest renal disease, prerenal azotemia,

or high dietary intake of protein. Prerenal azotemia from

dehydration was considered less likely because the indi-

viduals with higher PCVs or total protein concentrations

were not those with the higher urea and uric acid con-

centrations. These concentrations were most likely due

to dietary intake as captive reptiles are often fed high

protein diets consisting of whole rodents at increased

frequencies compared with wild-caught animals in the

beaded lizard study.

Data for protein electrophoresis have not been

reported for the genus Heloderma. In this study the

albumin fraction represented the largest single fraction

and was approximately equal to the combined globulin

fractions. Interestingly, the relative percentage of a-1

and -2 globulins was higher than is typical for most

mammalian species.32 Another interesting observation

was the prominence of the a-peak in these animals.

Similar prominent a-peaks have been reported in peo-

ple and species of Salamandra and Iguana and result

from the presence of bisalbuminemia.33,34 The cause of

the prominent a-peak in the Gila monsters is not clear.

It is important to consider that electrophoresis was per-

formed using plasma, and fibrinogen may have been a

contributing factor in the presence of the peak in the

late b and early g fractions. The use of electrophoretic

data is becoming an increasingly important modality

Table 5. Plasma protein electrophoretic values from 16 Gila monsters

(Heloderma suspectum).

Analyte Mean SD Minimum Q1 Median Q3 Maximum

Albumin (g/dL) 2.61 0.28 2.14 2.36 2.60 2.79 3.23

a-1 (g/dL)� 2.09 0.27 1.48 1.95 2.07 2.25 2.60

a-2 (g/dL)� 0.59 0.10 0.44 0.50 0.59 0.67 0.76

b (g/dL) 0.58 0.10 0.41 0.51 0.54 0.66 0.77

g (g/dL)� 0.33 0.13 0.18 0.25 0.33 0.40 0.68

Albumin (%) 42.1 2.2 38.7 40.1 42.0 43.5 46.5

a-1 (%)� 33.8 3.6 23.2 32.6 33.7 36.6 38.8

a-2 (%)� 9.4 1.2 7.3 8.7 9.3 10.4 11.3

b (%) 9.33 1.2 7.9 8.4 9.0 10.1 12.8

g (%)� 5.4 1.9 2.7 4.3 4.6 6.5 10.6

�Distribution of data not normal.

Q, quartile.

Figure 3. Plasma protein electrophoretograms from (A) a healthy wild

bred-captive Gila monster (Heloderma suspectum) with the albumin frac-

tion representing the largest single fraction and approximately equal to

the combined globulin fractions and (B) a captive-bred female with re-

tained eggs showing reduced albumin:globulin ratio. a-Globulins repre-

sented the highest single fraction in this animal, and a relative increase in

bridging between the b and g fractions was present.



for diagnosis of acute and chronic inflammatory dis-

eases, and values are being determined for different

reptilian species. However, comparisons are difficult

owing to species variation.7,35,36 During the course of

this study, electrophoretic data were collected from a

gravid female Gila monster with retained eggs, and

tracings from the healthy animals could be used as a

baseline for comparison. Reduced albumin:globulin

ratio and an increased globulin fraction with a-

globulins representing the greatest single protein frac-

tion were changes typical of those found in association

with chronic inflammation in mammalian species.32,37

Microfilaria have been reported in reptiles and

often do not cause overt clinical disease.23,25 Free-

ranging Gila monsters and 19% of wild-caught Mexi-

can beaded lizards have been reported to be parasitized

with an unidentified filarial parasite with no apparent

anemia or altered blood values.22,38 In this study, all of

the filaria-parasitized animals were asymptomatic and

it is likely that the parasitism did not affect results.

In conclusion, this study provides preliminary ref-

erence values for clinically healthy Gila monsters that

will aid veterinarians in clinical evaluation and moni-

toring of both healthy and ill Gila monsters. Further

work is needed to determine whether significant

differences in values between wild-caught and cap-

tive-bred animals are present.

Acknowledgments

The authors gratefully acknowledge Philip Bailey (Blacks-

burg, VA) and Christian Wright and Karla Moeller from the

School of Life Sciences, Arizona State University, Tempe,

AZ for their time and assistance in handling and sampling of

the animals and personnel from the Avian and Exotic Clin-

ical Pathology Laboratories (Wilmington, OH) for providing

the electrophoretic data.

Disclosure: The authors have indicated that they have

no affiliations or financial involvement with any organiza-

tion or entity with a financial interest in, or in financial

competition with, the subject matter or materials discussed

in this article.

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