Strain differences in song and hearing in canaries (Sernius canarius)

Abstract

Breeders have bred canaries either for specific song characteristics (song canaries) or morphology/plumage (type canaries) for centuries. Type canaries (e.g., Border and Gloster strains) retain song characteristics that are typically quite similar to those of wild canaries. By contrast, song canaries (e.g., Belgian Waterslager and Roller strains) have been selected for song types pleasing to the human ear, resulting in songs that, in most cases, are less complex, lower pitched, and narrower in a frequency range than songs from wild canaries. We now suspect that song selection in the Belgian Waterslager song canary has either directly or indirectly resulted in high-frequency hearing loss associated with hair cell abnormalities. Here, we compare hearing in the Belgian Waterslager and several other type and song canaries including the American Singer Canary. Though bred only since the 1930s, American Singer canaries also have a high-frequency hearing loss that looks very similar to that of the Belgian Waterslager and may have similar pathologies. Illumina whole genome sequencing has preliminarily identified a number of high-impact SnpEff variants in Belgian Waterslager and American Singer Canaries, some of which are related to deafness genes in mammals.