In Europe in general, such as the Netherlands / Belgium in particular, many breeders are selecting indukkan to be farmed, so only the big berbodi paired and bred. The result is that the body seedlings big. If the big berbodi constantly mated with another large body after a few generations, there was a large body of standardization in the lovebird.
Problem issues / myths that imports lovebird is barren, is NOT TRUE. I think the reality is, it takes a stage adaptation of the European regions (four seasons and the dry air humidity) to Indonesia (hot all year + of rain and high humidity regions). Not to mention the adjustment phase of shock / trauma air travel to bring them here. According to my experience with the Dutch import of birds, the adaptation time is about 6 months before they are accustomed and begin laying eggs. The children of these sires must have been accustomed to the climate of Indonesia so no need to adapt again after they become adults.
Link: lovebird holland