title: Pattern of gonadal differentiation and development up to sexual maturity in the frogs, Microhyla ornata and Hylarana malabarica: A comparative study.
abstract: Gonadogenesis was studied in Microhyla ornata (Family: Microhylidae) and Hylarana malabarica (Family: Ranidae) up to sexual maturity. Indifferent gonads of M. ornata directly differentiated into either testes or ovaries while those of H. malabarica differentiated into ovaries in all the individuals followed by testicular differentiation in males through an ovarian phase. In some tadpoles of M. ornata, formation of a central cavity at Gosner stage 27 marked ovary differentiation while meiosis was initiated at stage 29. Folliculogenesis was evident at stage 39. Vitellogenesis was initiated in females 9 months post-metamorphosis that attained maturity around 11 months after the completion of metamorphosis. Gonads of males with uniformly distributed germ and somatic cells remained undifferentiated until stage 41. Germ and somatic cells reorganized into seminiferous cords at stage 42. One month after completing metamorphosis, testes contained seminiferous tubules while those of 3 months old males exhibited all spermatogenic stages. In H. malabarica, germ cells entry into meiosis marked ovary differentiation at stage 29 while, ovarian cavity was discernable around stage 35. Post-metamorphosis, ovaries of 1-6 month old females contained pre-diplotene oocytes. Females were immature even 1 year after the completion of metamorphosis. In all the tadpoles, ovaries with central cavity and meiocytes were present up to the completion of metamorphosis. Gonads of prospective males displayed an obliterating ovarian cavity along with degenerating oocytes at the end of metamorphosis. Germ and somatic cells reorganized into seminiferous cords in males 3 months after the completion of metamorphosis. Testes of 4 months old males exhibited distinct seminiferous tubules while those of 6 months old exhibited meiosis. All spermatogenic stages were observed in testes of 9 months old males indicating maturity.
authors.affiliation: Department of Zoology, Savitribai Phule Pune University, Ganeshkhind, Pune, India.
authors.forename: Prajakta Vijay
authors.initials: PV
authors.lastname: Mali
authors.affiliation: Department of Zoology, Savitribai Phule Pune University, Ganeshkhind, Pune, India.
authors.forename: Narahari Prabhakar
authors.initials: NP
authors.lastname: Gramapurohit
mesh_terms: D000818:Animals; D001001:Anura / Q000254:growth & development*; D005260:Female; D006066:Gonads / Q000254:growth & development*; D007814:Larva / Q000254:growth & development; D008297:Male; D008675:Metamorphosis, Biological; D009865:Oocytes; D010053:Ovary / Q000254:growth & development; D011898:Ranidae / Q000254:growth & development; D012733:Sex Differentiation; D013091:Spermatogenesis; D013737:Testis / Q000254:growth & development