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Jacob sheep

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Jacob
a piebald sheep with four horns
Conservation status
Other names Spanish Sheep
Country of origin United Kingdom
Standard Jacob Sheep Society
Traits
Weight
  • Male: 54 to 82 kg (120 to 180 lb)
  • Female: 36 to 54 kg (80 to 120 lb)
Wool colour piebald – black or grey with white patches
Face colour badger-faced – black cheeks and muzzle, white blaze
Horn status horned in both sexes; may have two or four horns[3]
At pasture near Ashley in Gloucestershire
Four-horned Jacob skull in the anatomy museum of the Royal Veterinary College in London
In the Wildpark Tambach (de), at Schloss Tambach (de) in Weitramsdorf, in Coburg, Bavaria

The Jacob is a traditional British breed of domestic sheep. It combines two characteristics unusual in sheep: it is piebald – dark-coloured with areas of white wool – and it is often polycerate or multi-horned. It most commonly has four horns. The origin of the breed is not known; broken-coloured polycerate sheep were present in England by the middle of the seventeenth century, and were widespread a century later. A breed society was formed in 1969, and a flock book was published from 1972.

The Jacob was kept for centuries as a "park sheep", to ornament the large estates of landowners. In modern times it is reared mainly for wool, meat and skins.

History[edit]

The origin of the Jacob is not known.[4]:4 It has been bred in the British Isles for several hundred years. Sheep of this kind, little different from the modern breed, were shown in paintings from about 1760 at Tabley House in Cheshire, and – by George Stubbs – at Wentworth Woodhouse in Yorkshire.[5]:77

In the de Tabley family, the tradition was that the piebald sheep had come ashore in Ireland from a wrecked ship of the Spanish Armada in 1588, and been brought to England by Sir John Byrne on his marriage.[6]:33

Among the many accounts of ancient breeds of piebald sheep is the story of Jacob from the first book of the Hebrew Bible, called by Christians the Old Testament. According to the Book of Genesis (Genesis 30:31–43), Jacob took every speckled and spotted sheep from his father-in-law's (Laban's) flock and bred them. Due to the resemblance to the animal described in Genesis, the Jacob sheep was named for the Biblical figure of Jacob[7][8] sometime in the 20th century.[9]

In 2009, a study which used endogenous retrovirus markers to investigate the history of sheep domestication found the Jacob to be more closely linked to sheep from Africa and South-west Asia than to other British breeds,[4]:4 though all domestic breeds can be traced back to an origin the Fertile Crescent.[10]

Some believe that the modern breed is actually the same one mentioned in the Bible, having accompanied the westward expansion of human civilisation through Northern Africa, Sicily, Spain and eventually England.[11] Elisha Gootwine, a sheep expert at the Israeli Agriculture Ministry, says that the resemblance of a British breed to the Bible story is a coincidence, that the breed was not indigenous to ancient Israel, and that "Jacob Sheep are related to Jacob the same as the American Indians are related to India".[10]

The Jacob was referred to as the "Spanish sheep" for much of its early recorded history. It has been bred in England for at least 350 years,[8][12] and spotted sheep were widespread in England by the mid–18th century. By that time, Jacobs were often kept as ornamental animals grazed in parks, which probably kept the breed extant.[7]

A breed society, the Jacob Sheep Society, was formed in July 1969.[13] Mary Cavendish, dowager Duchess of Devonshire, who had a flock of Jacob sheep at Chatsworth House in Derbyshire, was the first president of the society.[14] From 1972 onwards, the society published a flock book.[15]

Jacobs were first exported to North America in the early 20th century.[12] Some individuals acquired them from zoos in the 1960s and 1970s, but the breed remained rare in America until the 1980s; registration began in 1985. The first North American association for the breed, the Jacob Sheep Breeders Association, was established in 1989.[citation needed] The Jacob was introduced to Israel in 2016, when a small flock of about 120 head was shipped there from Canada[16][17][18][19][20] by a couple who believes the breed is the same one mentioned in Genesis.[10]

Conservation status[edit]

In 2012 the total Jacob population in the UK was reported to the DAD-IS database of the FAO as 5638, of which 2349 were registered breeding ewes.[21] In 2017, the Rare Breeds Survival Trust listed the Jacob in Category 6 ("Other UK Native Breeds") of its watchlist, in which categories 1–5 are for various degrees of conservation risk, and category 6 is for breeds which have more than 3000 breeding females registered in the herd-book.[2] Small numbers of Jacobs are reported from four other countries: the Czech Republic, Germany, the Netherlands and the United States, with conservation status in those countries ranging from critical to endangered-maintained.[22]

Characteristics[edit]

The Jacob is a small, multi-horned, piebald sheep that resembles a goat in its conformation. However, it is not the only breed that can produce polycerate or piebald offspring. Other polycerate breeds include the Hebridean, Icelandic, Manx Loaghtan, and the Navajo-Churro, and other piebald breeds include the Finnsheep and the West African Dwarf.

Mature rams (males) weigh about 54 to 82 kg (120 to 180 lb), while ewes (females) weigh about 36 to 54 kg (80 to 120 lb).[23] The body frame is long, with a straight back and a rump that slopes toward the base of the tail. The rams have short scrotums free of wool which hold the testicles closer to the body than those of modern breeds, while the ewes have small udders free of wool that are also held closer to the body than those of modern breeds.[23] The head is slender and triangular, and clear of wool forward of the horns and on the cheeks.[23] The tail is long and woolly, extending almost to the hock if it has not been docked. Jacob owners do not usually dock the tail completely, even for market sheep, but instead leave several inches (several centimetres) to cover the anus and vulva. The legs are medium-length, slender, free of wool below the knees, and preferably white with or without coloured patches. The hooves are black or striped.[23] It is not unusual for Jacobs to be cow-hocked. They provide a lean carcass with little external fat, with a high yield of meat compared to more improved breeds.[11]

Horns[edit]

The most distinguishing features of the Jacob are their four horns, although they may have as few as two or as many as six.[7][9][12][24] Both sexes are always horned, and the rams tend to have larger and more impressive horns.[7] Two-horned rams typically have horizontal double-curled horns. Four-horned rams have two vertical centre horns which may be 61 cm (2 ft) or more in length, and two smaller side horns, which grow down along the sides of the head. The horns on the ewe are smaller in diameter, shorter in length and appear more delicate than those of the ram.[24] British Jacobs most often have two horns, while American Jacobs are more often polycerate. Polled (hornless) sheep are not registrable, since this trait is considered an indication of past cross-breeding, and as such there is no such thing as a polled purebred Jacob.[25]

The horns are normally black, but may be black and white striped; white horns are undesirable. Ideally, horns are smooth and balanced, strongly attached to the skull, and grow in a way that does not impede the animal's sight or grazing abilities. Rams have larger horns than ewes. The horns in two-horned sheep, and the lower horns in four-horned animals, grow in a spiral shape. The rostral set of horns usually extend upwards and outwards, while the caudal set of horns curls downwards along the side of the head and neck. On polycerate animals it is preferred that there is a fleshy gap between the two pairs of horns. Partial or deformed horns that are not firmly attached to the skull, often referred to as "scurs", are not unusual but are considered undesirable.[23]

Markings[edit]

a piebald ewe suckling a lamb
Ewe suckling her lamb

Each Jacob has distinctive markings that enable the shepherd to identify specific sheep from a distance. Desirable colour traits include an animal which is approximately 60% white, with the remaining 40% consisting of a random pattern of black or "lilac" (brownish-gray)[7] spots or patches.[23] The skin beneath the white fleece is pink, while skin beneath coloured spots is darkly pigmented. Both rams and ewes exhibit black markings, some of which are breed specific and some of which are random.[23]

Breed specific markings include large, symmetrical dark patches incorporating the ears, eyes and cheeks, and a dark cape over the dorsal part of the neck and shoulders. The face should have a white blaze extending from the poll to the muzzle. The muzzle itself should be dark. The classic Jacob face is often referred to as "badger-faced", consisting of black cheeks and muzzle with a white blaze running down the front of the face.[24] In addition to these markings, random spots may occur on the rest of the body and legs (including the carpi, hocks, and pasterns). Certain markings are common in particular lines: large muzzle markings, lack of leg markings, lack of muzzle markings, etc.[24]

Diseases[edit]

Several rare or unusual diseases have been identified in Jacob sheep.

The condition known as split eyelid is a congenital defect common to several polycerate British breeds, and is genetically linked to the multi-horned trait. In mild cases, the eyelid shows a "peak" but does not impair vision or cause discomfort. Extreme cases (Grade 3 or higher) result in a complete separation of the upper eyelid in the middle.[23][26]

In 1994, an unusual form of asymmetric occipital condylar dysplasia was found in two Jacob lambs; a possible link to the multi-horn trait has been suggested.[27]

In 2008, researchers in Texas identified the hexosaminidase A deficiency known in humans as Tay–Sachs disease in four Jacob lambs.[28][29] Subsequent testing found some fifty carriers of the genetic defect among Jacobs in the United States.[30] The discovery offers hope of a possible pathway to effective treatment in humans.[31]

Husbandry[edit]

The Jacob is generally considered to be an "unimproved" or "heirloom" breed (one that has survived with little human selection).[32] Such breeds have been left to mate amongst themselves, often for centuries, and therefore retain much of their original wildness and physical characteristics. American breeders have not subjected Jacobs to extensive cross-breeding or selective breeding, other than for fleece characteristics.[7] Like other unimproved breeds, significant variability is present among individuals within a flock. In contrast, the British Jacob has been selected for greater productivity of meat, and therefore tends to be larger, heavier and have a more uniform appearance. As a result, the American Jacob has retained nearly all of the original phenotypic characteristics of its Old World ancestors while its British counterpart has lost many of its unimproved physical characteristics through cross-breeding and selective breeding. The British Jacob has thus diverged from the American Jacob as a result of artificial selection.[7]

Jacobs are typically hardy, low-maintenance animals with a naturally high resistance to parasites and hoof problems.[11] Jacobs do not show much flocking behaviour. They can be skittish if not used to people, although with daily handling they will become tame and make good pets. They require shelter from extreme temperatures, but the shelter can be open and simple. They tend to thrive in extremes of heat and cold and have good or excellent foraging capabilities. They can secure adequate nutrition with minimal to no supplementation, even in the presence of suboptimal soil conditions.[32][33]

Due to their low tail dock and generally unimproved anatomy, Jacob ewes are widely reputed to be easy-lambing.[24] Jacobs are seasonal breeders, with ewes generally cycling in the cooler months of the autumn. They will begin to cycle during the first autumn following their birth and most often the ewe's first lamb is a single. Subsequent gestations will typically bear one or two lambs in the spring, and triplets are not unusual. The lambs will exhibit their spotting and horn characteristics at birth, with the horn buds more readily apparent on ram lambs. Lambs may be weaned at two months of age, but many shepherds do not separate lambs and allow the ewe to wean the lamb at about 4 months of age.[24] Jacob ewes are instinctively attentive mothers and are protective of their lambs. They are included in commercial flocks in England because of their ease of lambing and strong mothering instincts.[11][8]

Use[edit]

Wool and skins[edit]

Photograph of a Jacob ewe in full fleece
Ewe in full fleece near Ewhurst in Sussex

Jacobs are shorn once a year, most often in the spring. The average weight of the fleece is 2–2.5 kg (4–6 lb). The wool is medium to coarse: staple length is about 8–15 cm (3–6 in) and fibre diameter about 32–34 microns (Bradford count 48s–56s).[34]:830

In general, the fleece is light, soft, springy and open, with little lanolin (grease);[citation needed] there may be some kemp.[citation needed] In some sheep (particularly British Jacobs, which have denser fleeces), the black wool grows longer or shorter than the white wool. This is called "quilted fleece", and is an undesirable trait.[35]

While other British and Northern European multi-horned sheep have a fine inner coat and a coarse, longer outer coat,[36] Jacobs have a medium grade fleece and no outer coat.[11][24] Lambs of the more primitive lines are born with a coat of guard hair that is protective against rain and cold; this birth coat is shed at 3–6 months.[24]

Some individual sheep may develop a natural "break," or marked thinning, of the fleece in springtime, which can lead to a natural shedding of the fleece, particularly around the neck and shoulders. The medium-fine grade wool has a high lustre, and is highly sought after by handspinners if it is free of kemp.[citation needed] The colours may be separated or blended after shearing and before spinning to produce various shades of yarn from a single fleece, from nearly white to nearly black.[24] Tanned Jacob sheepskins also command high market prices.[12]

References[edit]

General
Specific
  1. ^ Barbara Rischkowsky, D. Pilling (eds.) (2007). List of breeds documented in the Global Databank for Animal Genetic Resources, annex to The State of the World's Animal Genetic Resources for Food and Agriculture. Rome: Food and Agriculture Organization of the United Nations. ISBN 9789251057629. Accessed May 2017.
  2. ^ a b Watchlist 2017–18. Stoneleigh Park, Warwickshire: Rare Breeds Survival Trust. Accessed May 2017.
  3. ^ Breed Standard. Exeter, Devon: Jacob Sheep Society. Accessed May2017.
  4. ^ a b Chessa B, Pereira F, Arnaud F, Amorim A, Goyache F, Mainland I, et al. (2009). "Revealing the History of Sheep Domestication Using Retrovirus Integrations" (PDF). Science. 324 (5926): 532–6. ISSN 0036-8075. PMC 3145132Freely accessible. PMID 19390051. doi:10.1126/science.1170587. Retrieved 9 June 2017. 
  5. ^ J.A. Fraser Roberts (1926). Colour Inheritance in Sheep, II: The Piebald Pattern of the Piebald Breed. Journal of Genetics 17 (1): 77–83. doi:10.1007/BF02983308.
  6. ^ Henry John Elwes (1913). Guide To The Primitive Breeds Of Sheep And Their Crosses On Exhibition At The Royal Agricultural Society's Show, Bristol 1913. Edinburgh: Printed by R. & R. Clark.
  7. ^ a b c d e f g American Livestock Breeds Conservancy (2009). "Jacob Sheep". Pittsboro, North Carolina: American Livestock Breeds Conservancy. Retrieved 5 May 2011. 
  8. ^ a b c American Jacob Sheep Registry (2006). "About the Jacob Sheep...". McKean, Pennsylvania: American Jacob Sheep Registry. Retrieved 5 May 2011. 
  9. ^ a b "Jacob". Breeds of Sheep. Oklahoma State University. Retrieved 5 May 2011. 
  10. ^ a b c Farmers On Mission To Return 'Old Testament Sheep' To Holy Land
  11. ^ a b c d e Jacob Sheep Breeders Association (2009). "About Jacob Sheep". Dexter, Oregon: Jacob Sheep Breeders Association. Retrieved 5 May 2011. 
  12. ^ a b c d Simmons and Ekarius, Chapter 2: Breeding and Breeds, pp. 30–98 in Simmons and Ekarius (2009)
  13. ^ History of the Jacob Sheep Jacob Sheep Conservancy. Accessed May 2017.
  14. ^ The Society: History & Function. Exeter, Devon: Jacob Sheep Society. Accessed May2017.
  15. ^ [Jacob Sheep Society] (1972). Flock book / Jacob Sheep Society. Ringwood: The Society.
  16. ^ Udasin, Sharin (29 June 2015). "Canadian Couple Aiming to Help Jacob Sheep 'Make Aliyah". Jerusalem Post. 
  17. ^ Lou, Ethan (2 March 2016). "Israeli Couple Bringing Home Biblical Sheep from Canada". Reuters. 
  18. ^ Levin, Dan (4 March 2016). "Biblical Nomads will Return to the Holy Land Thanks to a Canadian Farm". New York Times. 
  19. ^ Friends of the Jacob Sheep (1 April 2016). "About". Friends of the Jacob Sheep. 
  20. ^ Lidman, Melanie (28 December 2015). "Baa Baa Biblical Sheep, Do you have an Israeli Passport". Times of Israel. 
  21. ^ Breed data sheet: Jacob/United Kingdom. Domestic Animal Diversity Information System of the Food and Agriculture Organization of the United Nations. Accessed May 2017.
  22. ^ Transboundary breed: Jacob. Domestic Animal Diversity Information System of the Food and Agriculture Organization of the United Nations. Accessed May 2017.
  23. ^ a b c d e f g h Jacob Sheep Breeders Association (2009). "JSBA Breed Standard". Dexter, Oregon: Jacob Sheep Breeders Association. Retrieved 5 May 2011. 
  24. ^ a b c d e f g h i Horak F, Horak J (2010). "What is a Jacob Sheep?". Lucas, Texas: Jacob Sheep Conservancy. Retrieved 5 May 2011. 
  25. ^ American Jacob Sheep Registry (2005). "Description of the Jacob Sheep". McKean, Pennsylvania: American Jacob Sheep Registry. Retrieved 5 May 2011. 
  26. ^ Elizabeth Henson (1981). A Study of the Congenital Defect 'Split Eyelid' in the Multi-Horned Breeds of British Sheep. ARK VIII: 84–90.
  27. ^ Gayle C. Johnson, James R. Turk, Terry S. Morris, Dennis O'Brien, E. Aronson (1994). Occipital condylar dysplasia in two Jacob sheep. The Cornell Veterinarian 84 (1): 91–98.
  28. ^ Porter BF, Lewis BC, Edwards JF, Alroy J, Zeng BJ, Torres PA, Bretzlaff KN, Kolodny EH (2011). "Pathology of GM2 Gangliosidosis in Jacob Sheep". Veterinary Pathology. 48 (3): 807–13. ISSN 0300-9858. PMID 21123862. doi:10.1177/0300985810388522. 
  29. ^ Horak F (2009). "Jacob Sheep Shed Light on Tay Sachs Disease". ALBC Newsletter. Pittsboro, North Carolina: American Livestock Breeds Conservancy. Retrieved 5 May 2011. 
  30. ^ Kolodny E, Horak F, Horak J (2011). "Jacob sheep breeders find more Tay-Sachs carriers". ALBC Newsletter. Pittsboro, North Carolina: American Livestock Breeds Conservancy. Retrieved 5 May 2011. 
  31. ^ Torres PA, Zeng BJ, Porter BF, Alroy J, Horak F, Horak J, Kolodny EH (2010). "Tay-Sachs disease in Jacob sheep". Molecular Genetics and Metabolism. 101 (4): 357–63. ISSN 1096-7192. PMID 20817517. doi:10.1016/j.ymgme.2010.08.006. 
  32. ^ a b Wooster and Hansen, Chapter 2: Choosing a Flock, pp. 11–28 in Wooster and Hansen (2005)
  33. ^ Simmons and Ekarius, Chapter 3: Pasture, Fences, and Facilities, pp. 99–134 in Simmons and Ekarius (2009)
  34. ^ Valerie Porter, Lawrence Alderson, Stephen J.G. Hall, D. Phillip Sponenberg (2016). Mason's World Encyclopedia of Livestock Breeds and Breeding (sixth edition). Wallingford: CABI. ISBN 9781780647944.
  35. ^ Jacob Sheep Breeders Association (2006). "Jacob sheep in the show ring: information for judges" (PDF). Dexter, Oregon: Jacob Sheep Breeders Association. Retrieved 5 May 2011. 
  36. ^ Dýrmundsson, ÓR; Niżnikowski, R (2009). "North European Short-tailed Breeds of Sheep: a Review". Animal. 4 (8): 1275–1282. ISSN 1751-7311. doi:10.1017/S175173110999156X. Retrieved 5 May 2011. 

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