For the first and second points, you can anticipate based factors. But for the third point, the necessary special tips such as the following.
The feathers are too thick either the male and female parent could hinder the process of fertilization. It was also difficult for the males when they wanted to marry a female. It is necessary for actions that are important, namely to cut feathers around the cloaca.
Trim or shave that is too thick around the cloaca of walnuts will give you a greater chance of success when mating.
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