A comparison of the brainstem auditory evoked response in healthy ears of unilaterally deaf dogs and bilaterally hearing dogs

M Plonek,K Kubiak,J Nicpoń,M Wrzosek

doi:10.1007/s11259-016-9668-3

M Plonek, K Kubiak + Show 2 more

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https://doi.org/10.1007/s11259-016-9668-3

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Abstract

AimsAuditory plasticity in response to unilateral deafness has been reported in various animal species. Subcortical changes occurring in unilaterally deaf young dogs using the brainstem auditory evoked response have not been evaluated yet. The aim of this study was to assess the brainstem auditory evoked response findings in dogs with unilateral hearing loss, and compare them with recordings obtained from healthy dogs.MethodsBrainstem auditory evoked responses (amplitudes and latencies of waves I, II, III, V, the V/I wave amplitude ratio, wave I-V, I-III and III-V interpeak intervals) were studied retrospectively in forty-six privately owned dogs, which were either unilaterally deaf or had bilateral hearing. The data obtained from the hearing ears in unilaterally deaf dogs were compared to values obtained from their healthy littermates.ResultsStatistically significant differences in the amplitude of wave III and the V/I wave amplitude ratio at 75 dB nHL were found between the group of unilaterally deaf puppies and the control group. The recordings of dogs with single-sided deafness were compared, and the results showed no statistically significant differences in the latencies and amplitudes of the waves between left- (AL) and right-sided (AR) deafness.ConclusionsThe recordings of the brainstem auditory evoked response in canines with unilateral inborn deafness in this study varied compared to recordings from healthy dogs. Future studies looking into electrophysiological assessment of hearing in conjunction with imaging modalities to determine subcortical auditory plasticity and auditory lateralization in unilaterally deaf dogs are warranted.

Highlights

The peripheral auditory system serves to change sound wave energy into electrical impulses, and animals have learnt to use it primarily for communication in the course of evolution
A statistical significance was noted between the amplitudes of wave III in groups A and B (p < 0.05) at 75 dB, with the mean amplitudes higher in group of unilaterally deaf dogs (group A) (1.03 vs 0.70 μV, Fig. 3)
A statistical significance was noted between the V/I wave amplitude ratio at that sound intensity (Fig. 4)

Summary

Introduction

The peripheral auditory system serves to change sound wave energy into electrical impulses, and animals have learnt to use it primarily for communication in the course of evolution. Canine congenital sensorineural deafness occurs in at least 90 breeds of dogs, predominantly due to cochleosaccular degeneration taking place within six weeks after birth (Strain 1996). The mode of inheritance of deafness in predisposed breeds has not yet been established autosomal recessive, autosomal pleiotropic recessive and polygenic mechanisms have been suggested. Many of these studies closely associate hearing impairment with pigmentation (Strain 2004). Several studies have suggested a higher incidence of unilateral deafness than bilateral hearing loss in affected breeds (Holliday et al 1992; Rak and Distl 2005; Strain 2004)

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