I have been keeping my female guppies virgin for almost 6 months. They have been getting nice and plump. Will be adding them to the boys tomorrow (line breeding). Interestingly I read that if you keep females virgin too long they can get to a point where they no longer are able to have fry.
Wow now I am really disheartened. I didn't realize that there was such a cut off point. Although another breeder wrote that it may just take a little longer because older guppies will have fewer ovulations, especially moscows. in any case i have the trios swimming in about a four gal tub. I hate waiting for results.