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Published on: June 2, 2018
Tonometry in adult yellow-footed tortoises (Geochelone denticulata)
A L Selmi1, G M Mendes, C MacManus
1Faculdade Anhembi Morumbi São Paulo, São Paulo, Brazil. andre_selmi@yahoo.com.br
Objective:
To determine intraocular pressure (IOP) in adult yellow-footed tortoises using applanation tonometry.
Animals:
Fifteen healthy adult captive yellow-footed tortoises (eight males and seven females).
Procedures:
Intraocular pressures were estimated for tortoises by using an applanation tonometer after topical anesthesia. Body length, measured from nuchal to anal scutes, ranged from 27.5 to 57.2 cm. Five measurements from each eye were obtained by a single observer in an ambient temperature of approximately 30 degrees C.
Results:
Mean +/- SEM IOP of 30 eyes of 15 yellow-footed tortoises was 14.2 +/- 1.2 mmHg. Range of IOP was 6-30 mmHg for tortoises. Significant differences were detected neither between right and left eyes (P = 0.357) of individual tortoises, nor between males and females (P = 0.524). Observer's readability was good (intraclass coefficient = 0.65), and IOP did not change over the ordered five measurements.
Conclusions:
There was no significant difference in IOP between males and females in this specie. Tonometry values for normal eyes may represent a useful diagnostic methodology for recognition and treatment of ocular diseases in reptiles.

