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Successful and accurate feather sexing in commercial one day-old chicks is very important. Be aware that one single sexing error made by the observer in the parent stock can generate plenty of offspring in which feather sexing can no longer be successfully applied. Especially parent stock males can have a big impact as they mate with so many females. In the white parent stock flocks, the sexing errors can easily be identified by the status of their comb: all leghorns males with non-dubbed combs should be taken out, this also accounts for the parent stock females with dubbed combs.
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