Biology:Sebright chicken

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Short description: British breed of bantam chicken


Sebright
Sebright Gold Doré.jpg
A Golden Sebright cock
Conservation status
Country of originUnited Kingdom
DistributionWorldwide
UseFancy
Traits
Weight
  • Male:
    620 g[4]:268
  • Female:
    510 g[4]:268
Egg colourWhite
Comb typeRose
Classification
APAYes[5]
EEyes[6]
PCGBTrue bantam[7]
APSTrue bantam softfeather light breed
  • Chicken
  • Gallus gallus domesticus

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.

History

Background

Sir John Saunders Sebright (1767–1846) was the 7th Sebright Baronet, and a Member of Parliament for Hertfordshire.[10] In addition to breeding chickens, cattle and other animals, Sir John wrote several influential pamphlets on animal keeping and breeding: The Art of Improving the Breeds of Domestic Animals (1809), Observations upon Hawking (1826),[11] and Observations upon the Instinct of Animals (1836).[10]

A Silver Sebright hen

Charles Darwin read Sir John's 1809 pamphlet, and was impressed with a passage that elaborated on how "the weak and the unhealthy do not live to propagate their infirmities".[12] These writings, along with Darwin's correspondence via their mutual friend William Yarrell,[13] aided Darwin in the inception of Darwin's theory of natural selection.[12] Darwin's seminal work On the Origin of Species, first published in 1859, cited Sir John's experiments in pigeon breeding,[14] and recalled "That most skilful breeder, Sir John Sebright, used to say, with respect to pigeons, that 'he would produce any given feather in three years, but it would take him six years to obtain head and beak.'"[15] Darwin also cited Sir John extensively regarding the Sebright bantam, as well as pigeon and dog breeding, in his 1868 work Variation of Plants and Animals Under Domestication, his 1871 The Descent of Man, and Selection in Relation to Sex, and his book on Natural Selection (which was not published in his lifetime).[16]

Sebright set out to create a very small bantam chicken with laced plumage similar that of the laced Polish.[12] Although the exact makeup of the breed is uncertain, it is thought that he created the gold Sebright by cross-breeding a buff Nankin bantam hen, a small gold-spangled Hamburgh-like hen and a small hen-feathered Pit Game cock; he later created the silver Sebright by crossing his golds with a white Rosecomb cock bought from the new Zoological Gardens of the Zoological Society of London, established in 1826.[1][17] It is also possible that the hen-feathering characteristic derived from the Belgian Campine breed rather than from Pit Game.[17] In about 1810, Sebright founded The Sebright Bantam Club, which was the first single-breed association for chickens.[18] In 1853 the Sebright was described in the Poultry Book of William Wingfield and George William Johnson, with an illustration by Harrison Weir.[19]:190 It was included in the original Standard of Excellence in Exhibition Poultry of William Bernhard Tegetmeier in 1865,[20]:47 and in the first Standard of Perfection of the American Poultry Association in 1874.[citation needed] Today, the breed is one of the ten most popular bantam chickens, according to the American Bantam Association.[21]

Characteristics

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] Lua error in Module:Multiple_image at line 163: attempt to perform arithmetic on local 'totalwidth' (a nil value). 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]

Husbandry

Sebrights are neither outstanding meat birds nor prolific egg layers – hens lay some 60–80 creamy-white eggs per year.[9] They can prove to be particularly difficult to raise, especially for beginners. Hens rarely go broody and chicks usually have high mortality rates. Adults are generally hardy, but are especially susceptible to Marek's disease.[28] Like many bantams, they fly well, so are sometimes kept in confinement, and not allowed to range freely.[22] Due to their genetic makeup, males may on occasion be born infertile, further complicating breeding.[9]

See also

  • 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

Notes

  1. ↑ 1.0 1.1 Sebright. Rare Breeds Survival Trust. Accessed January 2019.
  2. ↑ "Chooks - Rare Breeds List". Rare Breeds Conservation Society of New Zealand. http://www.rarebreeds.co.nz/chooks.html#true. 
  3. ↑ "Status of Rare Breeds of Domestic Farm Livestock in Australia 2004". Rare Breeds Trust of Australia. http://www.rbta.org/Pdf%20Files/Status%20of%20Rare%20Breeds%20in%20Australia%20v10.pdf. 
  4. ↑ 4.0 4.1 Victoria Roberts (2008). British poultry standards: complete specifications and judging points of all standardized breeds and varieties of poultry as compiled by the specialist breed clubs and recognised by the Poultry Club of Great Britain. Oxford: Blackwell. ISBN:9781405156424.
  5. ↑ APA Recognized Breeds and Varieties: As of January 1, 2012. American Poultry Association. Archived 4 November 2017.
  6. ↑ 6.0 6.1 Liste des races et variétés homologuée dans les pays EE (28.04.2013). Entente Européenne d’Aviculture et de Cuniculture. Archived 16 June 2013.
  7. ↑ Breed Classification. Poultry Club of Great Britain. Archived 30 June 2017.
  8. ↑ Chickens: True Bantam. Poultry Club of Great Britain. Archived 27 October 2018.
  9. ↑ 9.0 9.1 9.2 Hobson, Jeremy and Lewis, Cecilia. Choosing & Raising Chickens: The complete guide to breeds and welfare. David and Charles publishing. London. 2009. p 85.
  10. ↑ 10.0 10.1 Lee p. 1108
  11. ↑ Sir John Sebright (1826). Observations upon Hawking. London" J. Harding.
  12. ↑ 12.0 12.1 12.2 Ekarius p. 152
  13. ↑ "Letter 613 Darwin, C. R. to Yarrell, William, [5 or 12 Sept 1842"]. Darwin Correspondence Project. http://www.darwinproject.ac.uk/darwinletters/calendar/entry-613.html. 
  14. ↑ Darwin 1859, p. 20.
  15. ↑ Darwin 1859, p. 31.
  16. ↑ "The Complete Work of Charles Darwin Online". http://darwin-online.org.uk/content/search-results?freetext=Sebright. 
  17. ↑ 17.0 17.1 17.2 Christopher Parker (October 2018). Sebrights. Aviculture Europe 14 (5), section 3. Accessed January 2019.
  18. ↑ Graham p. 144
  19. ↑ William Wingfield, George William Johnson, Harrison Weir (illustrator) (1853). The Poultry Book: comprising the characteristics, management, breeding and medical treatment of Poultry. London: Wm. S. Orr and Co.
  20. ↑ William Bernhard Tegetmeier (editor). The Standard of Excellence in Exhibition Poultry, authorized by the Poultry Club. London: Groombridge and Sons, for the Poultry Club, 1865.
  21. ↑ 21.0 21.1 Ekarius p. 153
  22. ↑ 22.0 22.1 Graham p. 145
  23. ↑ Australian Poultry Standards, 2nd Edition, published 2012 by Victorian Poultry Fanciers Association Ltd. trading as Poultry Stud Breeders and Exhibitors Victoria.
  24. ↑ Graham p. 144-145
  25. ↑ Fredrick, George W.; Noble, Janet F.; Wilson, Jean D. (July 1981). "Female Feathering in Sebright Cocks Is Due to Conversion of Testosterone to Estradiol in Skin". Science 213 (4507): 557–559. doi:10.1126/science.213.4507.557. PMID 17794843. Bibcode: 1981Sci...213..557G. http://www.sciencemag.org/cgi/content/abstract/213/4507/557. Retrieved 20 April 2008. 
  26. ↑ Matsumine, H; Wilson, JD; McPhaul, MJ (1990). "Sebright and Campine chickens express aromatase P-450 messenger RNA inappropriately in extraglandular tissues and in skin fibroblasts". Molecular Endocrinology 4 (6): 905–911. doi:10.1210/mend-4-6-905. PMID 1700281. http://mend.endojournals.org/cgi/content/abstract/4/6/905. Retrieved 20 April 2008. 
  27. ↑ Carefoot, W.C. (May 1992). "Inheritance of the lace-tailed laced plumage pattern of the sebright bantam". British Poultry Science 33 (2): 297–302. doi:10.1080/00071669208417468. 
  28. ↑ Hobson p. 119
  29. ↑ Holland, Bill. Golden and Silver Sebright Bantams. American Bantam Association: 1980. pp. 2-3

References



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