Breed-specific expression mode of the Wnt signalling pathway is involved in feather follicle morphogenesis between <i>Anser cygnoide</i> and <i>Anser anser</i>

Feathers are important economic products. Anser cygnoide (AC) is superior in reproduction, growth and feather quality, while Anser anser (AA) has an advantage in feather yield. Understanding the development of feather follicles facilitates deliberate crossbreeding. Here, we compared feather follicles morphogenesis between AC and AA. Feathers and dorsal skin were sampled at multiple embryonic days to investigate feather phenotypes, feather follicle morphology and the expression of hub molecules (FZD4, β-catenin, LEF1, TCF4 and c-Myc) in the Wnt signalling pathway. We found a marked difference in plumage colour between the two breeds. Feather colour in AA has undergone a ‘black dorsum’ stage and cavity formation in AC was earlier. Furthermore, different trends in molecular hub expression helped explain the phenotypical and morphological differences: the upregulated Wnt signals in AC at E12 and/or E15, as well as in AA at E18, were associated with early epidermal placode formation and cavity formation in AC, also, related to the development of the secondary feather follicles and ‘black dorsum’ in AA. Summarily, breed-specific expression patterns of Wnt signalling pathway between AC and AA might participate in the shaping of breed-specific feather follicles morphogenesis and feather phenotypes. This work provides references for feather follicles development in geese.