Ocular Findings in A Captive Population of African Clawed Frogs (Xenopus laevis) and Tiger Salamanders (Ambystoma tigrinum).

PURPOSE: This study aimed to investigate and report ocular findings in a group of healthy captive African Clawed Frogs (Xenopus laevis) and Tiger Salamanders (Ambystoma tigrinum) and to establish reference data for commonly performed ocular diagnostic tests.

METHODS

Seven female adult captive African Clawed Frogs (ACF) and seven adult captive Tiger Salamanders (TS) were included. All animals underwent ophthalmic examination, Cochet-Bonnet corneal esthesiometry, rebound tonometry (Tonovet Plus), and conjunctival bacterial aerobic culture. Mann-Whitney tests were used for comparisons between species. Significance was set at p < 0.05.

RESULTS

One frog exhibited a typical iris coloboma bilaterally and 2/7 frogs exhibited unilateral punctate cortical cataracts. Retinal evaluation was unremarkable in 13/14 frog eyes. One frog exhibited a large chorioretinal scar in one eye. Tonometry was (median, min-max) 24 mmHg (18-36) and corneal touch threshold (CTT) was (median, min-max) 2.25 mm, (1.0-3.0). Five of seven frogs had positive culture results. Four of the 7 salamanders had bilateral nuclear cataracts and 2 of those 4 also had cortical cataracts. Retinal exam in this species was precluded. Tonometry was (median, min-max) 19.5 mmHg, (14-23) and CTT were > 5.0 cm in all individuals. All TS had positive bacterial cultures, mostly gram-negative rods. ACF had significantly less corneal sensitivity and a significantly higher IOP than TS (p < 0.0001 and p = 0.0003, respectively).

CONCLUSIONS

TS and ACF can be manageable for ophthalmic examination and minimal diagnostic testing without chemical restraint. This study provides preliminary baseline ophthalmic data in captive Tiger Salamanders and African Clawed Frogs examined without sedation.