Int. J. Dev. Biol. 58: 819 - 827 (2014)
doi: 10.1387/ijdb.140147rp
© UPV/EHU Press

Bidder’s organ – structure, development and function

Rafal P. Piprek*,1, Malgorzata Kloc4,5 and Jacek Z. Kubiak2,3

1Department of Comparative Anatomy, Institute of Zoology, Jagiellonian University, Krakow, Poland, 2CNRS, UMR 6290, Institute of Genetics and Development of Rennes, Cell Cycle Group, France, 3Université Rennes 1, UEB, UMS Biosit, Faculty of Medicine, Rennes, France, 4Department of Surgery, The Houston Methodist Hospital, Houston, USA and 5The Houston Methodist Research Institute, Houston, USA

ABSTRACT Bidder’s organ is an ovary-like structure, which develops from the anterior part of the gonadal ridge in anuran amphibians belonging to the Bufonidae family. Bidder’s organs form in both males and females. Because Bidder’s organ contains female germ cells (oocytes), the bufonid males are de facto hermaphrodites. Due to similarity with the undeveloped ovary, Bidder’s organ was, in early literature, described, inaccurately, as a structure present only in males. Due to the fact that Bidder’s organ is a unique structure present only in Bufonidae, it is not well studied and its function still remains a mystery. Here we describe the development and structure of Bidder’s organs, summarize the knowledge on gene expression and steroidogenic activity in these organs, and present hypotheses regarding Bidder’s organ function.


Bidder’s organ, testis, ovary, oocytes, sex hormones

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