Cystoscopic sex identification of posthatchling chelonians.

OBJECTIVE

To describe a noninvasive technique for sex identification of posthatchling chelonians and to assess its safety in Hermann's tortoises (Testudo hermanni).

DESIGN

Validation study and clinical trial.

ANIMALS

15 recently dead posthachling chelonians and 25 healthy posthatchling Hermann's tortoises.

PROCEDURES

Cystoscopy was performed on both dead and anesthetized live chelonians. Dead chelonians ranged in body weight from 32.4 to 75.1 g (0.07 to 0.17 lb; median, 45.7 g [0.10 lb]). Dead chelonians were dissected immediately after cystoscopy, and gonads were collected for histologic examination. Urinary bladder was macroscopically evaluated in situ to assess its integrity after retrograde injection of saline (0.9% NaCl) solution. Hermann's tortoises ranged in body weight from 27.3 to 57.8 g (0.06 to 0.13 lb; median, 37.0 g [0.08 lb]). Cystoscopic examination of live tortoises was performed following induction of general anesthesia with a mixture of morphine, dexmedetomidine, and ketamine administered IM. The Pearson coefficient was used to assess the consistency between procedure time and body weight; κ statistic was used to evaluate agreement between sex identified by cystoscopy and histologic examination beyond that expected by mere chance.

RESULTS

Visualization of gonads was feasible through the thin, transparent urinary bladder wall in all the animals evaluated in this study. Blinded histologic examination confirmed the results of cystoscopic gonad identification in all dead chelonians (κ = 1.0). The urinary bladder did not have evidence of macroscopic leakage or microscopic alterations of normal tissue architecture within the representative sections chosen for histologic examination. In live tortoises, median procedure time (range) was 90 (39 to 345) seconds. No significant correlations were found between procedure time and body weight.

CONCLUSIONS AND CLINICAL RELEVANCE

Cystoscopy performed by means of rigid endoscopy with fluid instillation was found to be an effective method for sex identification of immature chelonians. Furthermore, no complications were observed when this procedure was performed in vivo.