Assessing Hearing Loss due to Ototoxic Drugs in the Zebra Finch

Abstract

Aminoglycosides such as kanamycin and amikacin are ototoxic drugs that cause hair cell damage/loss that leads to hearing loss in humans and animals. Previous studies show both hearing loss and recovery following administration in birds. I assessed the effects of aminoglycoside treatment in the budgerigar, canary, and zebra finch using auditory brainstem response (ABR). The purpose of this study was to determine whether the ABR can accurately measure hearing loss following treatment, and to compare the effect of two aminoglycosides on zebra finch hearing sensitivity. After treatment, budgerigar and canary ABR audiograms were similar to those found through behavioral methods confirming the ABR as an efficient tool to measure hearing loss and recovery. Interestingly, zebra finches did not show the expected hearing loss but instead showed small threshold shifts across all frequencies. Overall, the zebra finch appears to be far less susceptible to aminoglycoside induced hearing damage than other birds.