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Powder down, or pulviplumes, is a special type of down that occurs in a few groups of apparently unrelated birds. In some species, the tips of the barbules on powder down feathers disintegrate, forming fine particles of keratin, which appear as a powder, or "feather dust", among the
Rather, powder down feathers are spread across the body. These have a tendency to disintegrate, and the powder, akin to talcum powder, helps maintain the plumage. [50] Some varieties of domestic pigeon have modified feathers called "fat quills". These feathers contain yellow, oil-like fat that derives from the same cells as powder down.
The gland is invariably present during embryonic development, whereas it can be vestigial in adults of certain orders, families, genera and species. Some or all species in at least nine families of birds lack a uropygial gland, mostly the ones unable to fly or the ones that produce powder down for feather maintenance. [2]
[22] [23] Some species that lack a preen gland instead have powder down feathers which continually break down into a fine dust that the birds apply to their contour feathers while preening. [24] These powder down feathers may be scattered throughout the bird's plumage or concentrated into dense patches. As well as helping to waterproof and ...
The basic color of Ice pigeons is a pale grey. They appear even lighter due to their abundant powder down, which covers the entire plumage in whitish dust; its Polish name Lazurek ("glazed pigeon") refers to this. The English and German names refer to the coloration, which in bright light appears "icy" white, with a very slight bluish hue.
Herons use their bill to break the powder down feathers and to spread them, while cockatoos may use their head as a powder puff to apply the powder. [24] Waterproofing can be lost by exposure to emulsifying agents due to human pollution. Feathers can then become waterlogged, causing the bird to sink.
One type of “pigeon” you are probably familiar with is the broad-tailed all-white dove often released to mark ceremonies or as a symbol of peace. That’s right, folks, doves are also pigeons.
In those species having powder down, signs may be visible immediately, as powder down feathers are continually replenished. It can also be expressed peracutely, ranging from sudden death, particularly in neonates, [ 33 ] to an acute form in nestling and fledglings, characterised by feather dystrophy , diarrhoea , weakness and depression ...