Hemolymph Cytology, Cell Count, and Electrolyte Reference Values in Cameroon Red Tarantula (Hysterocrates gigas)
American Association of Zoo Veterinarians Conference 2017
Cédric B. Larouche1,2, DVM, IPSAV; Janet Beeler-Marfisi1, BA, DVM, DVSc, DACVP; Lydia Attard2, MSc; Nicole Nemeth1, DVM, PhD, DACVP; Hugues Beaufrère1, DrMedVet, PhD, DACZM, DECZM (Avian), DABVP (Avian Practice)
1Ontario Veterinary College, University of Guelph, Guelph, ON, Canada; 2Toronto Zoo, Toronto, ON, Canada


Theraphosidae is a large family of tarantula spiders commonly kept as pets or display animals in zoological institutions. A variety of diseases and diagnoses have been reported in captive tarantulas.3 There has been a growing interest and demand over the last decade for arachnid medicine, but the range of currently available diagnostic tests is limited. Hemolymph analysis could be a fundamental tool for arachnid health assessment. The objective of this prospective study was to establish reference intervals for hemocyte counts, and acid-base and electrolyte parameters in Cameroon red tarantulas (Hysterocrates gigas). Ninety-nine mature Cameroon red tarantulas from the Toronto Zoo collection were anesthetized using isoflurane in an induction chamber for the collection of 0.35 ml of hemolymph from the dorsal opisthosoma. Electrolytes (sodium, chloride, potassium, ionized calcium, and bicarbonate) were measured using a radiometer (ABL800 FLEX, Radiometer America, Brea, CA, USA), and hemocyte counts were obtained using the Avian Leukopet™ system (Vetlab Supply, Palmetto Bay, FL, USA) and hemocytometer. Cytocentrifuge preparations of hemolymph were Wright’s stained, and a differential cell count was performed on all available cells. Due to rapid coagulation and degranulation of cells, preparations were made immediately after sampling. Reference intervals were calculated using a nonparametric approach with 90% confidence intervals of the reference limits.2 Hemocyte classification was based on the available literature.1,4,5 These results will help establish baseline reference intervals for use in tarantula medicine and will also allow for a more quantitative assessment and thus a better understanding of arachnid health.


This research was supported by an Ontario Veterinary College Pet Trust research fund.

Literature Cited

1.  Bednaski AV, Trevisan-Silva D, Matsubara FH, Boia-Ferreira M, Olivério MM, Gremski LH, Cavalheiro RP, De Paula DMB, Paredes-Gamero EJ, Takahashi HK, Toledo MS, Nader HB, Veiga SS, Chaim OM, Senff-Ribeiro A. Characterization of brown spider (Loxosceles intermedia) hemolymph: cellular and biochemical analyses. Toxicon. 2015;98:62–74.

2.  Friedrichs KR, Harr KE, Freeman KP, Szladovits B, Walton RM, Barnhart KF, Blanco-Chavez J. ASVCP reference interval guidelines: determination of de novo reference intervals in veterinary species and other related topics. Vet Clin Pathol. 2012;41:441–453.

3.  Pizzi R. Spiders. In: Lewbart G, ed. Invertebrate Medicine. 2nd ed. Ames, IA: Wiley-Blackwell; 2011:187–221.

4.  Scherman R. Chelicerates. In: Raticliffe NA, Rowley AF, eds. Invertebrate Blood Cells. New York, NY: Academic Press, Inc.; 1981:355–384.

5.  Soares T, Cavalcanti MG, Ferreira FR, Cavalcanti M do S, Alves LC, Brayner FA, Paiva PM. Ultrastructural characterization of the hemocytes of Lasiodora sp. (Koch, 1850) (Araneae: Theraphosidae). Micron. 2013;48:11–16.


Speaker Information
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Cédric B. Larouche, DVM, IPSAV
Ontario Veterinary College
University of Guelph
Guelph, ON, Canada

Toronto Zoo
Toronto, ON, Canada

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