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. <i>Anser cygnoide</i> (<i>AC</i>) is superior in reproduction, growth and feather quality, while <i>Anser anser</i> (<i>AA</i>) has an advantage in feather yield. Understanding the development of feather follicles facilitates deliberate crossbreeding. Here, we compared feather follicles morphogenesis between <i>AC</i> and <i>AA</i>. 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 <i>AA</i> has undergone a ‘black dorsum’ stage and cavity formation in <i>AC</i> was earlier. Furthermore, different trends in molecular hub expression helped explain the phenotypical and morphological differences: the upregulated Wnt signals in <i>AC</i> at E12 and/or E15, as well as in <i>AA</i> at E18, were associated with early epidermal placode formation and cavity formation in <i>AC</i>, also, related to the development of the secondary feather follicles and ‘black dorsum’ in <i>AA</i>. Summarily, breed-specific expression patterns of Wnt signalling pathway between <i>AC</i> and <i>AA</i> might participate in the shaping of breed-specific feather follicles morphogenesis and feather phenotypes. This work provides references for feather follicles development in geese.