"Undercoat" redirects here, but this term is also used to mean a layer of
paint below the top layer.Down hairs, also called the ground hairs, are the very fine, fluffy hairs closest to the
skin on some
mammals. The hairs are short and crimped, which makes them highly efficient for trapping
air and insulating the
animal. In the
hobby of
animal fancy, the down hair is collectively called the undercoat and is an important
conformation point in shows, particularly
dog and
cat shows.
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