title: Histological evaluation of gonadal differentiation in fathead minnows (Pimephales promelas).
abstract: The timing of sex determination and the pattern of sex differentiation have not been studied in fathead minnow even though this species of fish are commonly used as a research model for toxicological studies. In this study, the developmental histology of gonadal development was investigated. Fish were cultured in the laboratory conditions and spawning obtained at a photoperiod of 16 h-light and 8 h-dark. Samples were collected from day 7 fish post-spawning (day 7 fps) to day 150 fps and their gonads were processed for histological examination. Developmental histology was assessed by using a light microscopy. The results showed that ovarian differentiation normally occurs at around day 13 fps, while testicular differentiation normally occurs at around day 22 fps.
authors.affiliation: Department of Medical Biology and Genetics, Faculty of Veterinary Medicine, Afyon Kocatepe University, Afyonkarahisar, Turkey. cuguz@aku.edu.tr
authors.forename: Cevdet
authors.initials: C
authors.lastname: Uguz
mesh_terms: D000818:Animals; D003530:Cyprinidae / Q000196:embryology*; D005260:Female; D005854:Germ Cells / Q000166:cytology; D006066:Gonads / Q000166:cytology* / Q000196:embryology*; D008297:Male; D008540:Meiosis; D010053:Ovary / Q000166:cytology*; D011418:Prophase; D012733:Sex Differentiation; D013737:Testis / Q000166:cytology*; D013997:Time Factors