brood patch

In most birds a brood patch on the abdomen is developed. This bare area is fluid-filled (edematous) and highly vascularized; it directly contacts the eggs during incubation. Its development during the breeding season is under hormonal control. When the parent is off the nest, adjacent feathers are directed over…

…blood vessels), forming the so-called brood patches. Usually the female develops these patches, which serve to transfer more effectively to the eggs the warmth from the adult’s body. It has been shown that, like much of parental behaviour in the higher vertebrates, brood patches and “broodiness” are controlled by several…

Many birds develop a brood patch—an area of bare, featherless skin on the underbody—in preparation for incubation and brooding. A network of blood vessels in the skin of the brood patch raises the temperature locally. After the hatch, the parent birds brood their young, keeping them warm by spreading…