To improve a good lineage / produce tillers good, it would require a good quality male canary. Results of females mating with males who are not always able to produce good puppies male sex great as his father. However inbred female sex from a male great potential as a good parent to produce a good stud, though his brother might be ugly.
Many breeders canary does not allow the females to improve his line. When the canary females produce offspring that have a male canary singing bad quality, this does not mean that the female does not have the potential to produce good offspring. All walnuts, either male or female sex, definitely bring good or bad genes. For example, in a nest with four puppies will have different qualities, perhaps only one or two chicks are good sound quality, and others may have sufficient sound quality or even ugly.
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