Talk:Cat Development

Developmental changes of Müllerian and Wolffian ducts in domestic cat fetuses

Inomata T, Ninomiya H, Sakita K, Kashiwazaki N, Ito J, Ariga M, Inoue S. Exp Anim. 2009 Jan;58(1):41-5. PMID: 19151510

Development of external genitalia in fetal and neonatal domestic cats

J Vet Med Sci. 2009 Feb;71(2):139-45.

Inomata T, Ariga M, Sakita K, Kashiwazaki N, Ito J, Yokoh K, Ichikawa M, Ninomiya H, Inoue S.

Department of Laboratory Animal, School of Veterinary Medicine, Azabu University, Sagamihara, Kanagawa, Japan. inomata@azabu-u.ac.jp Abstract Development of the external genitalia of fetal and neonatal cat were studied macroscopically, paying attention to the formation of the labia and the sexual differentiation. The female urogenital folds budded from each side of the genital tubercle and, gradually extended to the tip of the genital tubercle by the 6.8 cm stage in crown-rump length. Then, the well-developed urogenital folds ensheathed completely the genital tubercle to form the prepuce of clitoris and the labia, flanking the external opening of vagina as the folds of skin which were equivalent to the labia minora in humans. The genital swellings known to become the labia majora in humans were clearly recognized in the caudolateral region of the genital tubercle during the fetal stage. These swellings became flat and obscure after birth. Thus, in cats the genital swellings did not join to the formation of the labia in the same way as in humans. The sex difference in the external genitalia was first observed at the 3.2-3.3 cm stages. In the male, the anogenital raphe appeared and the caudal portion of the genital swellings moved and fused each other at the caudal region of the genital tubercle. In the female, both features were not easy to observe.

PMID: 19262023