. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. TERRESTRIAL-BREEDING FROGS 169 in GVBD but also in ovulation (de Albuja el ai. 1983). The responses of G. riobambae oocytes to these hormones are equivalent to A', laevis and suggest that there are similar mechanisms for the conversion of an oocyte into an egg. The time of the response is longer in G. riobambae. The large oocytes of G. riobamhac need an exposure of 15- 24 h to progesterone to undergo GVBD compared to 6- 8 h for A", laevis oocytes (de Albuja et a/.. 1983). To induce ovulation, female G. riobambae are inj
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. TERRESTRIAL-BREEDING FROGS 169 in GVBD but also in ovulation (de Albuja el ai. 1983). The responses of G. riobambae oocytes to these hormones are equivalent to A', laevis and suggest that there are similar mechanisms for the conversion of an oocyte into an egg. The time of the response is longer in G. riobambae. The large oocytes of G. riobamhac need an exposure of 15- 24 h to progesterone to undergo GVBD compared to 6- 8 h for A", laevis oocytes (de Albuja et a/.. 1983). To induce ovulation, female G. riobambae are injected intraperitoneally with hCG. The amount given ranges from 200 to 1000 IU of hCG, administered in one or two doses at 6-24 h intervals. Ovulation and egg release oc- curred 29-76 h after hormone injection (de Albuja et ai, 1983). When a female injected with hCG is placed in a terrarium with male frogs, amplexus and mating occur readily. In some instances, the male was simultaneously stimulated by the intraperitoneal injection of 200-500 IU of hCG. Hormonal stimulation of amplexus and mating in G. riobambae greatly facilitates the study of reproduc- tion in this frog. The maternal pouch as an indicator of the female's re- productive condition. The pouch of G. riobambae is a sac of integument located on the back of the female, under the dorsal skin. The pouch is essentially independent from the skin, except at the aperture, where it is continuous with the dorsal skin. Pouch integument of frogs that are not incubating embryos is similar to frog skin. It differs from skin by the presence of abundant mucous glands, fewer serous glands, and the lack of keratinization of the epithelial layer (Jones et a/., 1973; del Pino et a/., 1975). The pouch of G. riobambae opens in the midline of the female's back and the aperture has an inverted V or U shape. The pouch can be open or closed according to the reproductive condition of the female (Fig. 1). The pouch of females with small ovarie
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
