Kanamycin induced low-frequency hearing loss in the budgerigar (Melopsittacus undulatus).
The chronic effects of kanamycin (KM) on hearing in the budgerigar were investigated by behavioral audiometry. The birds received a daily intramuscular injection of KM (100 mg/kg or 200 mg/kg) for 10 successive days, and absolute thresholds between pre- and post-treatment were compared. KM induced both transient and permanent low-frequency specific hearing loss; i.e., the elevation of threshold for frequencies below 1 kHz was greater than that for frequencies above 1 kHz. Moreover, the degree of hearing loss was dose dependent. The low-frequency selective effects of KM in the present study were contrary to the high-frequency specificity of aminoglycoside ototoxicity in mammals. To assess the effect of KM on auditory frequency resolution, critical ratios were estimated in pathological birds with low-frequency specific hearing loss. There was a linear relation between shift in critical ratio and shift in absolute threshold, suggesting that the increase in the critical ratio is due to a decrease in the efficiency of the detector mechanism rather than a change in the spectral resolving power of the birds.
Hashino
E
E
Department of Communication, Tokyo Woman's Christian University, Japan.
Sokabe
M
M
D000818:Animals; D001299:Audiometry; D001305:Auditory Fatigue / Q000187:drug effects; D001309:Auditory Threshold / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D034381:Hearing Loss / Q000139:chemically induced*; D007612:Kanamycin / Q000633:toxicity*; D008297:Male; D010240:Parakeets / Q000502:physiology*; D011563:Psittaciformes / Q000502:physiology*
D007612:Kanamycin