(A) Cellular morphology of CVC. (B) Cellular morphology of CVT. (C) Oil red staining of CVC. (D) Oil red staining of CVT. (E) Triglyceride content in CVC and CVT. (F) The relative mRNA expression of six genes related to differentiation and adipogenesis in duck adipocyte. *P < 0.05, ** P< 0.01.