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Selecting a breed of sheepThere are more than 1,000 breeds of sheep worldwide and more than 50 in the United States and Canada. While only a handful of sheep breeds are of economic importance, all breeds of sheep are important, as they contribute to the genetic diversity of the species and industry. Pictures and descriptions of more than two hundred sheep breeds can be found at www.sheep101.info/breeds.html.Deciding which breed (or breeds) to raise is an important decision that each shepherd must make. The goal(s) for raising sheep should be the primary consideration when deciding upon a breed (or breed type). This is because if you're interested in producing wool for the hand spinner's market, your breed choice would be much different than if meat will be your primary product to sell. Conversely you wouldn't choose "wool" breeds, if the majority of your income is going to come from meat. If your children want to compete in junior market lamb shows, choice of breed(s) will affect success in this segment of the sheep industry. Price and availability will also have a bearing on which breeds or crosses are chosen. At the same time, it is important to remember that there are no "best" breeds of sheep. All breeds have traits which may be good or bad, depending upon the production situtation. In addition, there is usually as much difference within a breed as between breeds. Crossbred, Purebred, or Registered? A crossbred is an animal whose sire (father) and dam (mother) are different breeds or breed types, while a purebred animal's parents are of the same breed or type. A registered or pedigreed animal has a known ancestry. However, it could be crossbred (percentage purebred) or purebred (fullblood), depending upon the registration policy of its breed association. Most sheep breeds have closed flock books, meaning only 100% purebred animals with registered parents can be registered in the flock book. Some breed associations have open flock books (e.g. Katahdin and Dorper) which allow percentage "purebreds" to be recorded by the breed association. Percentage sheep are usually recorded as part of an upgrading program. While purebred sheep usually sell for higher prices than crossbred sheep and registered animals tend to cost more than non-registered animals, breed type (or purity) or registration status is in no way indicative of quality or productivity. In fact, crossbred animals tend to be hardier and more productive than purebreds. This is due to "heterosis" or "hybrid vigor," a natural phenomenon in which the performance of crossbred offspring is superior to the average performance of the parents. Heterosis is maximized when a crossbred ewe is mated to a crossbred ram. Heterosis occurs to a lesser degree in "composite" breeds, such as the Katahdin and Polypay. Another advantage to crossbreeding is breed complementarity. This is when the weaknesses of one breed are offset by the strengths of the other breed(s) and vice versa. Unless the objective is to raise and market purebred and/or registered sheep, it is better to raise crossbred sheep. This is especially true for beginners. It's better to practice shepherding with hardier, less expensive animals. Breed Categories Oftentimes, it is more useful to look at breed "types" rather than individual sheep breeds. Breed types tend to share common characteristics and can usually be substituted for one another in a breeding program. The are several ways in which sheep breeds are categorized. They include purpose, use, face color, fiber type, and various physical or performance attributes. Purpose The most useful way to categorize sheep breeds is by their primary purpose: meat, wool, or dairy. While most sheep breeds are dual-purpose (i.e. they produce both meat and wool) and some are even triple-purpose (dairy, meat, and wool), most sheep breeds excel in either the production of meat, wool, or dairy -- seldom two or all three. Thus, if you want to milk sheep, you shouldn't choose a meat breed, even though it produces milk to feed its lambs. Nor should you choose a wool breed, if your primary purpose for raising sheep is meat production, even though wool breeds are harvested for meat. Use Sheep breeds are often categorized as to whether they are more suitable as a ram or ewe in the breeding program. Ram or "sire" breeds should excel in growth and carcass (meat) characteristics whereas ewe or "dam" breeds should excel in fitness (e.g. longevity, parasite resistance) and reproductive traits (early puberty, prolificacy, milk production). Sire breeds are often called "terminal sires" because their offspring from their matings are all marketed (terminated) whereas lambs sired by a ewe breed ram, such as Finnsheep, are often kept as flock (ewe) replacements. The most popular terminal sire breed in the United States is
the Suffolk. In Europe, it is the Texel. Some sheep breeds are
considered dual-purpose, because they have traits which make
them suitable as either a ram or ewe breed. Examples of dual
purpose breeds include Dorset, Columbia, and North Country Cheviot. Fiber or Coat Type Fine wool sheep Fine-wool sheep tend to be hardy and long-lived. Most trace their
ancestry to the Spanish Merino. Fine-wool sheep have a strong
flocking instinct and are well adapted to arid regions, such
as South Africa, Australia, and the western United States and
Canada. Fine wool sheep and their crosses are the most numerous
sheep in the U.S. sheep industry. Worldwide, they comprise approximately
50 percent of the sheep population. Medium wool sheep Hair Sheep Hair sheep are also categorized by their place of origin. Some
hair breeds originate from tropical climates (e.g. Barbados
Blackbelly and St. Croix). These breeds tend to be more resistant
to internal parasites. Other breeds originate from arid regions
and are best-adapted to similar conditions (e.g. Dorper and
Damara). The desert breeds tend to be heavier muscled than the
tropical breeds, whereas the tropical breeds tend to have superior
maternal characteristics.
Minor breeds grow a variety of different types of wool, from double-coated (e.g. Navajo Churro) to hair (e.g Wiltshire Horn) to black (e.g. Black Welsh Mountain) or spotted (e.g. Jacob). There are several breeds not included ASI's table that can be found in the United States. They include Gotland, Hog Island, Ile-de-France, Lacaune, Leicester Longwool, Santa Cruz, SAMM (South African Meat Merino), and Soay. Some of the breeds are rare, whereas others are being introduced via upgrading programs or embryos. Other characteristics Type of Tail Some breeds are grouped together because they have a special kind of tail. Fat-tailed or fat-rumped breeds make up about 25 percent of the world sheep population. They are well-adapted to arid regions and are found mostly in Africa and Asia. Among U.S. breeds, the Karakul is fat-tailed and the Tunis and Dorper have fat-tail origins. The U.S. is home to several breeds of the Northern European short or rat-tail variety of sheep: Finnsheep, Romanov, East Friesian, Shetland, Icelandic, and Soay. The tails of these short-tailed breeds do not need to be docked. The breeds are also known for their prolificacy (large litters). Prolificy Some breeds of sheep are noted for the birth of large litter sizes. Prolific breeds of sheep include Finnsheep, Romanov, Booroola Merino, Barbados Blackbelly, and British Milk Sheep. The Booroola Merino is noteworthy because it has a single gene that is responsible for its high reproductive rate. The "F" (fecundity) gene can be transferred to other breeds. A single gene affecting prolificacy has also been isolated in Icelandic and Cambridge sheep. In most sheep breeds, litter size is a quantitative trait affected by many different genes. Its heritability is low, approximately 10 percent. Rare and Heritage Breeds There are many organizations and individuals dedicated to the preservation of rare and heritage breeds of livestock. While heritage breeds are usually no longer of commercial significance, it is important to preserve their genetics for the purpose of biodiversity. Some of the heritage breeds are also hardier than many of the more popular breeds that have been exploited by the show ring. Heritage breeds are ideal for small, hobby farms or historical farms or estates. The Navajo Churro is the oldest breed of sheep in the United States. Another breed of great historical significance is the Leicester Longwool. Ewe Breed Selection The most important factors to consider when selecting a ewe breed, type, or cross are: 1. Adaptability to environment Adaptability Type of Wool or Coat Level of Reproduction When to Lamb Level of Care Ram Breed Selection Before choosing a ram breed, you first need to determine his primary purpose. Will he be used to sire market lambs or do you want him to sire ewe lamb replacements? Or both? For producing replacements, you need a ram with the appropriate type of wool/coat and reproductive characteristics. For market lamb production, you need a ram that will sire lambs
that are suitable for your target market(s). For example, if
you want to produce lambs for the mainstream, heavy lamb (100-140
lbs) markets, your choice of a ram breed would be very different
from the ram breed you would choose to sire lambs for the hot
house (35 to 50 lbs) or ethnic markets (60-100 lbs.) Some producers have been able to create a demand for the meat from certain breeds of sheep. For example, many ethnic buyers like hair sheep lambs because they are accustomed to similar-looking sheep in their homelands. Hair sheep and coarse, long wooled breeds are ideally suited to the freezer market, because their meat has a milder flavor than lambs from fine-wool breeding. At the same time, it is important to remember than diet exerts a larger influence on lamb flavor than genetics. Purebred rams are often favored over crossbred rams because
there will be more uniformity in their offspring. However,
crossbreed rams tend to be superior in their breeding ability. |
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Late updated
08-Feb-2010
by Susan Schoenian. Copyright© 2010. Sheep 101 and 201. |
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