The Sebright (IPA: /ˈsiːbraɪt/) is a British breed of bantam chicken. It is a true bantam – a miniature bird with no corresponding large version – and is one of the oldest recorded British bantam breeds.^[8] It is named after Sir John Saunders Sebright, who created it as an ornamental breed by selective breeding in the early nineteenth century.^[9]

The first poultry breed to have its own specialist club for enthusiasts, Sebrights were admitted to poultry exhibition standards not long after their establishment. Today, they are among the most popular of bantam breeds. Despite their popularity, Sebrights are often difficult to breed, and the inheritance of certain unique characteristics the breed carries has been studied scientifically. As a largely ornamental chicken, they lay tiny, white eggs and are not kept for meat production.

In accordance with the intentions of their creator, the Sebright is an ornamental bantam, and is commonly seen in competitive poultry shows. As a true bantam, all Sebrights are very small in stature; males weigh an average of 22 ounces (620 grams) and females 20 oz (570 g). Their short backs, proportionally large breasts, and downward-pointing wings combine to create an angular, jaunty look.^[22]

In the United Kingdom, two colour variants are recognised, gold and silver; these have a base of either dark gold or whitish silver, evenly laced around the edges with black. In other European countries other colours have been created: a black-laced lemon Sebright arose as a sport in Holland in the mid-twentieth century, and a chamois or white-laced buff variant was bred towards the end of the century; it is recognised by the Entente Européenne.^[17][6] The birds have unfeathered legs with slate-blue skin, and their beaks are ideally a dark horn colour. Cocks carry a rose comb covered with fine points, and a small spike that sweeps back from the head (called a leader). Combs, earlobes and wattles were originally a purple colour referred to in the fancy as mulberry,^[23] but today are often bright red though mulberry is still desired according to the standards in most countries.^[21] Some breeders consider hen feathering to have an adverse effect on the fertility of male Sebrights, and may use cocks that don't carry the trait for breeding purposes, despite their automatic disqualification in shows.^[24]

Characteristically, Sebrights are only one of a few chicken breeds in which the cocks are hen-feathered, meaning they have none of the long, sickle-shaped feathers common in most cocks that appear in the tail, neck and saddle. Due to the unique characteristic hen feathering, molecular biologists have found the Sebright bantam a useful model organism in the study of sex hormones.^[25] This is because they carry a mutation that causes the tissues of their skin to convert an unusually large amount of male sex hormones (androgens) into female sex hormones (oestrogens).^[26][27]

• List of chicken breeds
• Pigmy Pouter (An English breed of fancy pigeon believed to also be developed by Sir John Sebright though the subject is debatable) ^[29]
• Campine (chicken) A small breed of chicken that also comes in gold and silver variants; is often compared to the Sebright.
• Hen feathering in cocks