Comb (anatomy)

A comb is a fleshy growth or crest on the top of the head of gallinaceous birds, such as turkeys, pheasants, and domestic chickens. Its alternative name cockscomb (with several spelling variations) reflects that combs are generally larger on males than on females (a male gallinaceous bird is called a cock). There can be several fleshy protuberances on the heads and throats of gallinaceous birds, i.e. comb, wattle, ear lobes and nodules, which collectively are called caruncles, however, in turkeys caruncle refers specifically to the fleshy nodules on the head and throat.

Chicken combs are most commonly red (but may be black or dark purple in breeds such as Silkies or Sebrights), but in other species the color may vary from light grey to deep blue or red; turkey combs can vary in color from bright red to blue.

The comb may be a reliable indicator of health or vigor and is used for mate-assessment in some poultry species.

Comb shape varies considerably depending on the breed or species of bird. The "comb" most often refers to chickens in which the most common shape is the "single comb" of a rooster from breeds such as the Leghorn. Other common comb types are the "rose comb" (e.g. the Rosecomb) or "pea comb" (e.g. the Brahma or the Araucana). Other distinctive shapes have been selectively bred for, such as the "buttercup comb" of the Sicilian Buttercup, "V combs" (popularly called "devil horn") in the Houdan and other breeds, the "cushion comb" of the Chantecler, and "walnut comb" of Malay game.

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