Tail-feather picking seems to begin by the birds' using each others' tail
feathers to clean their beaks of mash. Although it does not ordinarily
damage the birds for market, the habit ruins their appearance and
decreases their salability as breeding stock. It is not always possible
to prevent tail-feather picking entirely, especially in flocks raised in
confinement or in small range lots, but it may be prevented partially by
providing tightly stretched wire in or over the mash feeders. Baling wire
stretched tightly or strips of ordinary light-weight poultry wire may be
used.
Feeding the mash moist will also aid in preventing tail-feather picking.
The kind of mash may also be a factor. A rather coarse mash containing
considerable ground corn, some bran, and some coarsely ground oats or
barley, including the hulls, seems to be more palatable than a fine mash
and is not so likely to clog the beaks of the birds.