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Hematological analyses of specimens of D. coriacea are rare. Deem et al. (2006) collected blood samples from 35 females laying eggs on the coast of the Republic of Gabon, using the interdigital veins of the posterior fins, a technique described by Wallace & George (2007). Werneck et al. (2008) employed this method on a leatherback in rehabilitation on the coast of Brazil and Montilla et al. (2008) used the technique on specimens found in Venezuela.

Here we describe an alternative site for collecting blood from leatherbacks, which was used on a 146 cm. curved carapace length male leatherback found stranded on a beach in the state of São Paulo, Brazil and subsequently sent to rehabilitation. Upon admittance to the rehabilitation center, the turtle was found to be emaciated and its left rear flipper was amputated at the humerus-radius-ulna joint. The distal portion of the humerus was exposed and the entire surrounding tissue was scarred. The longitudinal crests on the left side of the carapace were damaged and scarred.

Figure 1. Blood collection from the tail of a male leatherback from Brazil. (Photographed by Paula Baldassin).

The turtle was placed daily on a wooden board for topical treatment of the wounds and for collection of blood samples. Prior to sampling, the entire post-cloaca region was cleaned with running water and a povidone-iodine solution, followed by antisepsis with iodated alcohol. The tail was maintained in the horizontal position and the 25 G x 7 in. needle was inserted in the ventral midline (at 90º), approximately 10-15 cm. posterior to the cloacal aperture, in the middle between the cloacal aperture and the final tail. The needle was inserted approximately 2 cm. into the skin (Fig 1). There was no contact with the bone during the procedure. The method was successfully used for blood collection throughout the turtle days in treatment.

Owens & Ruiz (1980) describe the dorsal cervical sinus as the site of choice for blood collection in sea turtles. This site has been widely used with success for hard-shelled sea turtles. However, Wallace & George (2007) noted the disadvantages of the dorsal cervical sinus as a collection site for adult leatherbacks, mainly due to the neck size, and some authors describe the interdigital veins as the preferred site in this species, which provide safety during the collection process and allow a great amount of blood volume for analysis.

Blood collection from the caudal veins has been employed on non-marine chelonians, lizards and crocodilians (Jenkins 1996). We found that collecting blood from the vessels of the tail was safe, it was easily accessible and it allowed sufficient volume of blood to be collected, which is an important characteristic describes by Wallace & George (2007). However, we recognize male leatherbacks have a longer tail than females, thus the efficacy of the technique should be tested on females. As well, because our study animal was in rehabilitation, it was logistically easy for us to access the tail; it may be logistically challenging for researchers to access the caudal veins of the tails of adult female leatherbacks nesting on sandy beaches. Finally, we were unable to verify that blood hematology results were the same for samples collected from the dorsal sinus and the caudal vein (see Wallace & George 2007). Subsequent investigations of different blood collection sites could clarify this
issue in these animals.

Acknowledgements. The authors thank Olé Web staff, Marcella Baldassin and José Carlos Barroso for the image help.

DEEM, S.L., S. DIRENFELD, G.P. SOUNGUET, A.R. ALLEMAN, C. CRAY, R.H. POPPENGA, T.M. NORTON & W. KARESH. 2006. Blood values in free-ranging nesting leatherback sea turtles (Dermochelys coriacea) on the coast of the Republic of Gabon. Journal of Zoo and Wildlife Medicine 37: 464-471.

HARMS, C.A., S.A. ECKERT, S.A. KUBIS, M. CAMPBELL, D.H. LEVENSON & M.A. CROGNALE. 2007. Field anaesthesia of leatherback sea turtles (Dermochelys coriacea). Veterinary Record 161: 15-21.

JENKINS, J.R. 1996. Diagnostic and clinical techniques. In: Mader, D.R. (Ed.). Reptile Medicine and Surgery. W. B. Saunders, Philadelphia. pp. 264-276.

LUTCAVAGE, M.E., P.G. BUSHNELL & D.R. JONES. 1990. Oxygen transport in the leatherback sea turtle Dermochelys coriacea. Physiological Zoology 65: 1012-1024.

MONTILLA F., A.J., J.L. HERNÁNDEZ R. & H.J. GUADA M.. 2008. Hematological values in leatherback sea turtles (Dermochelys coriacea) in Querepare beach, Paria peninsula, Sucre state, Venezuela. In: Rees, A.F., M. Frick, A. Panagopoulou & K. Williams (Comps.). Proceedings of the 27th Annual Symposium on Sea Turtle Biology and Conservation. NOAA Tech Memo NMFS-SEFSC-569. pp. 15-16.

OWENS, D.W. & G.J. RUIZ. 1980. New methods of obtaining blood and cerebrospinal fluid from marine turtles. Herpetologica 36: 17-20.

WALLACE, B.P. & R.H. GEORGE. 2007. Alternative techniques for obtaining blood samples from leatherback turtles. Chelonian Conservation & Biology 6: 147-149.

WERNECK, M.R., G.H.P. DUTRA & B.M.G. GALLO. 2008. Analysis of a live stranded leatherback, Dermochelys coriacea, in Brazil. Marine Turtle Newsletter 122:8-9.