Feather Eumelanin Distribution Variations in Buff Orpington, New Hampshire and Rhode Island Red Breeds of Fowl

Abstract

DUNN (1922, 1923) was the first investigator to recognize that a recessive gene, which he designated as em, was responsible for the Columbian restriction pattern in fowls homozygous for it. This gene restricts black pigment (eumelanin) to the areas of the hackle, primary and secondary flight feathers, primary flight coverts, and the tail feathers. In 1922, Dunn established that em was the recessive allele of Em, the determiner for extension of black pigment to all areas of the plumage. Self-blacks, however, had previously been analyzed by Lippincott (1918) in his studies with the Blue Andalusian, and their phenotype attributed to a dominant gene given the symbol E. Due to this priority, em has been referred to as e in most references since Dunn’s report.The buff-red breeds of fowl all have the black plumage pigment restricted to the above mentioned regions of the body, although there is considerable variation in …