PMC:514616 / 19157-21044
Annnotations
{"target":"https://pubannotation.org/docs/sourcedb/PMC/sourceid/514616","sourcedb":"PMC","sourceid":"514616","source_url":"http://www.ncbi.nlm.nih.gov/pmc/514616","text":"Conclusions\nIn an effort to conserve declining populations of animals, the development of protocols for the artificial manipulation of reproduction is of great interest. In the case of the neotropical frog E. coqui, we have observed that a large proportion of eggs that are laid unfertilized auto-activate. We showed that E. coqui eggs are easily activated by mechanical stimuli, leading to a need for careful manipulation of unfertilized eggs in all reproduction studies. Further, the cleavage pattern seen in mechanically activated eggs is similar to that of both auto-activated and chemically activated eggs, suggesting that mechanical stress, probably incurred in during oviposition, is responsible for the auto-activation mentioned above (table 1). Facile auto-activation of eggs has been reported in other species, complicating reproductive manipulation [48]. In E. coqui, this phenomenon may relate to internal fertilization, and it would be interesting to investigate auto-activation of unfertilized eggs in closely related, externally fertilizing species such as E. antillensis [38]. Some E. coqui eggs, however, remain intact and can be manipulated, showing signs of activation both at the morphological level, through the initiation of development, as well as the functional, through the slow block to polyspermy. By careful handling, we are now able to fertilize over half of the remaining, functionally viable eggs using a simple procedure. Finally, we have shown that E. coqui eggs do not degenerate rapidly and are capable of undergoing activation up to ten hours after deposition, thus creating a window of time for carrying out experimental procedures. Our results demonstrate efficient IVF in an internally fertilizing, terrestrial-breeding frog and help lay the foundation for future research and conservation possibilities in this unusually large genus of amphibians.","divisions":[{"label":"Title","span":{"begin":0,"end":11}}],"tracks":[{"project":"2_test","denotations":[{"id":"15296510-14512506-133587975","span":{"begin":861,"end":863},"obj":"14512506"}],"attributes":[{"subj":"15296510-14512506-133587975","pred":"source","obj":"2_test"}]}],"config":{"attribute types":[{"pred":"source","value type":"selection","values":[{"id":"2_test","color":"#93b4ec","default":true}]}]}}