Measurement of Tear Production Using the Phenol Red Thread Test in the Common Mynah ( Acridotheres tristis ).

Abstract

To evaluate tear production in the common mynah ( Acridotheres tristis ) using the phenol red thread test (PRTT) and to make a comparison of measurements with the PRTT placed in the fornices of lower and upper eyelids, tear production of both eyes in 22 healthy adult captive mynah birds was evaluated. After positioning of threads in the fornices of upper and lower eyelids, the PRTT values of the birds were 17.5 ± 3.1 mm/15 s and 19.2 ± 2.5 mm/15 s, respectively. A significant difference was found between PRTT values for upper eyelids and lower eyelids (P = 0.01). This study provides novel data for normal reference ranges of PRTT values in healthy common mynah birds and shows that a difference is found depending on where the PRTT thread is placed.