Sheep 201: Breed Selection

Selecting a breed of sheep

According to some estimates, there are more than 1,000 breeds of sheep worldwide and more than 50 in the United States alone. More breeds are being introduced to the US all the time, mostly via imported semen or embryos. While only a handful of breeds are probably of economic importance to the commercial industry, all breeds have value, as they contribute to the genetic diversity of the species and worldwide industry.

Deciding which breed (or type) of sheep to raise is an important decision that each shepherd must make with thoughtful consideration. The reason(s) for raising sheep should be primary consideration(s) when deciding upon breeds or types. This is because if you are 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 should not choose "wool" breeds, if the majority of your income is going to be derived from the sale of lambs (meat) or dairy. If your children or grandchildren want to compete in 4-H or junior market lamb shows, breed will affect their competitiveness in the show ring, thus their satisfaction with the experience. Price and availability will also have a bearing on which breeds are chosen. Not all breeds are available in all geographic areas. It is not easy or inexpensive to import live animals, semen, and embryos from other countries

It is important to understand that there are no "best" breeds of sheep. All breeds have traits which may make them desirable or undesirable, depending upon the production system and marketing objectives. A breed may be "best" for one production environment or market and a poor choice for others. 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 of different breeds or breed types, while a purebred animal's parents are of the same breed or type. A registered animal has a known ancestry with a documented pedigree. However, it could be crossbred (percentage purebred) or purebred (fullblood), depending upon the requirements 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 animals to be recorded by the breed association. Percentage sheep are usually recorded as part of an upgrading program. Once they reach a certain percentage of purebreeding, they are eligible for full registration.

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 and especially productivity. In fact, crossbred animals tend to be hardier and more productive than their purebred counterparts.

The "superiority" of crossbred animals is due primarily to "heterosis" or "hybrid vigor," a natural phenomenon whereby the performance of the crossbred offspring is superior to the average performance of the parent breeds. Heterosis is maximized when a crossbred ewe is mated to a crossbred ram. The effects of heterosis are additive: individual + dam + sire. Traits which response poorly to selection generally have higher levels of heterosis. Heterosis still occurs to some extent in the newer "composite" breeds, such as Katahdin and Polypay.

Another advantage to crossbreeding is breed complementarity. Breed complementarity is when the weaknesses of one breed are offset by the strengths of the other breed and vice versa. When utilizing breed complementarity, it is important utilize breeds in their appropriate roles. For example: crossing a Suffolk to Katahdin to produce crossbred lambs balances the superior growth and meat type of the Suffolk with the outstanding maternal characteristics of the Katahdin. The reverse cross would be the same genetically, but it would not be using the breeds in their appropriate roles.

Unless the objective is to raise and sell purebred and/or registered sheep, it is almost always better to raise crossbred or unregistered sheep. This is especially true for beginners. It is better to "practice" shepherding with hardier, less expensive animals. As shepherds, we also tend to make excuses for purebred or registsered animals that we pay a lot for. Shepherds are more likely to cull a less expensive crossbred ewe or ram.

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. There are several ways in which sheep breeds can be categorized, including purpose, use, face color, fiber type, and various physical or performance attributes.

Purpose
The most useful way to categorize sheep breeds is according to 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.

**Classification of U.S. sheep breeds by their primary purpose**
Wool	Meat	Dual or Multi- purpose	Other specialty, rare
Fine wool American Cormo Booroola Merino Delaine-Merino Debouillet Rambouillet Panama	Hair American Blackbelly Barbados Blackbelly Dorper Katahdin Romanov Royal White St. Augustine St. Croix Wiltshire Horn	Wool Columbia Corriedale Finnsheep Icelandic Polypay SAMM Targhee Dairy Awassi East Friesian Lacaune	Black Welsh Mountain Calif. Variegated Mutant Clun Forest Florida Cracker Gotland Gulf Coast Native Herdwick Hog Island Jacob Karakul Kerry Hill Navajo-Churro Racka Shetland Soay Valais Blacknose
Long wool Bluefaced Leicester Border Leicester Coopworth Cotswold Leicester Longwool Lincoln Perendale Romney Scottish Blaceface Teesdale Wensleydale	Wooled Border Cheviot California Red Charollais Dorset Hampshire Ile de France Montadale North Country Cheviot Oxford Rideau Arcott Shropshire Southdown Suffolk Texel Tunis

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 excel in growth and carcass (meat) characteristics whereas ewe or "dam" (maternal) breeds excel in fitness (e.g. longevity, parasite resistance), reproductive traits (early puberty, prolificacy, milk production), and sometimes wool production (staple length, fiber diameter).

Sire breeds are often called "terminal sires" because the offspring from their matings are all marketed (terminated) whereas lambs sired by a maternal ram, such as Finnsheep, are usually kept as flock (ewe) replacements. The most popular terminal sire breed in the United States is still probably the Suffolk. Hampshires are also popular for this purpose. In Europe, the Texel is the most popular sire of market lambs. Texels are becoming increasing popular as a terminal sire breed in the US, especially if lambs are finished on pasture.

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 the Dorper, Dorset, Columbia, and North Country Cheviot.

Some breeds fall under the "landrace" category. A landrace is a breed that is locally-adapted, developing over time, under natural conditions. Landrace breeds are influenced more by natural selection than the artificiall selection that has shaped most of today's more popular breeds. Landrace breeds represent a valuable genetic resource. Many of the rare or heritage breeds are landrace.

Face Color
Wooled sheep breeds are often classified by their face color. Black or non-whiteface breeds (e.g. Suffolk, Hampshire, Shropshire, Oxford, and Southdown) tend to excel in growth and carcass traits, whereas the white-face breeds (e.g. Rambouillet, Targhee, and Polypay) tend to have superior maternal and wool traits.

In some countries, black-face sheep are strongly discriminated against because the dark fibers and hairs in their fleeces can contaminate a wool clip. In Australia, they developed the White Suffolk breed to prevent this problem. There is some effort in the United States to develop a similar whiteface terminal sire breed.

Fiber or Coat Type

One of the most common ways to categorize sheep breeds is according to the type of fibers they grow or type of coat they have. All sheep grow both hair and wool fibers. Hair breeds have more hair fibers than woolly fibers and usually shed their coats annually. Some hair breeds have few if any wool fibers in their coats, especially if they are being raised in a warm climate. Hair sheep usually do not require shearing, crutching, or docking.

In contrast, wooled breeds have more woolly fibers and need to be sheared, usually at least once per year. Ideally, wooled sheep should be crutched, if they are not sheared prior to lambing. Crutching is the removal of wool around the vulva area and udder. Originally, all sheep were hair sheep. The soft, short undercoat ("down") of hair sheep was favored in selection programs and led to the development of the wooled breeds of today.

Ideally, hair sheep and wool sheep should not be raised together in the same pasture or pens, if high quality wool is the production objective. This is because hair fibers from the hair sheep may contaminate the fleeces of wool sheep. The risk of contamination may be low, but because it is possible, some wool mills will not purchase wool from flocks that comingle hair and wool sheep. The fleeces from hair x wool sheep should be discarded to prevent contamination of wool clips.

Fine wool sheep
Fine-wool sheep grow wool fibers with the smallest fiber diameter (usually less than 22 microns). A micron is one millionth of a meter, too small to be detected by the naked eye. Fine wool fleeces tend to be shorter in length and contain the most lanolin (wool wax or grease). Though some fine wool fleeces are high yielding, fine wool fleeces usually yield a lower percentage of clean fiber than longer, coarser fleeces. Fine wool is the most valuable wool in the commercial marketplace because it is used to make the highest quality wool garments and has the most versatility of use. Fine-wool is less likely to itch when it is used in garments that are close to the skin.

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 climates, such as South Africa, Australia, and the western United States and Canada. Fine wool sheep (mostly Rambouillet) and their crosses are the most numerous sheep in the U.S. sheep industry. Worldwide, fine wool sheep comprise approximately 50 percent of the sheep population.

Long wool sheep
At the other end of the spectrum are long or coarse wooled sheep. They grow wool fibers that have a larger fiber diameter (usually more than 30 microns) and longer staple length. Their fleeces tend to yield more clean fiber because they usually contain less lanolin. Carpet wool is even longer and coarser than long wool. Long wool sheep do best where feed resources are abundant.

Long wool sheep are most common to cool, wet climates such as the United Kingdom, New Zealand, and the Falkland Islands. Many of the long wooled breeds in the U.S. can trace their ancestry to the British Isles. The fleeces from the long wooled breeds tend to be favored by hand spinners and weavers. Long wooled sheep are often favored by shepherds who want to niche market their fleeces.

Medium wool sheep
The length and fiber diameter of medium wool fibers is intermediate between fine and long. Most of the meat-type breeds grow medium wool. Medium-wool sheep comprise about 15 percent of the world sheep population and include some of the most popular US breeds.

Hair Sheep
It is estimated that hair sheep comprise about 10 percent of the world's sheep population, and their popularity is increasing in temperate climates such as North America and Europe. In the United States, there are two general types of hair sheep: "improved" and "unimproved" (or landrace) breeds. The unimproved breeds tend to be indigenous sheep breeds that have adapted well to the local environment in which they evolved. Examples include the Barbados Blackbelly and St. Croix.

The American Blackbelly or "Barbado" is believed to be a cross between the Barbados Blackbelly, Mouflon, and Rambouillet. The Wiltshire Horn is a shedding sheep native to the British Isles. The improved hair breeds are crosses between hair sheep breeds and meat-type, wooled breeds. Examples include the Dorper, Katahdin, Royal White, and St. Augustine.

Hair sheep can also be differentiated 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).

Specialty wools
There are many breeds which produce specialty-type wools. Carpet wool is the coarsest wool produced by sheep. As the name implies, carpet wool is used to make carpets. Double-coated breeds grow a longer outer coat and a short fine undercoat. Primitive breeds have similar types of fleeces (inner and outer) that naturally shed. There are a few breeds whose fleeces are a specific color or color pattern. The Shetland breed produces wool in the widest range of colors of any breed. Jacobs produce a spotted fleece.

**Classification of U.S. sheep breeds by wool or coat type**
Fine	Medium (meat)	Long (coarse)	Specialty
American Cormo Booroola Merino Debouillet Delaine-Merino Rambouillet SAMM	Babydoll Southdown Border Cheviot Charollais Clun Forest Dorset Florida Cracker Gulf Coast Native Hampshire Hog Island Ile de France Kerry Hill Louisiana Native Montadale North Country Cheviot Oxford Panama Rideau Arcott Romeldale Santa Cruz Shropshire Southdown Suffolk Texel Tunis	Blueface Leicester Border Leicester Coopworth Cotswold Leicester Longwool Lincoln Perendale Romney Teeswater Valais Blacknose Wensleydale	Carpet Awassi Herdwick American Karakul Scottish Blackface Colored Calif. Variegated Mutant California Red Black Welsh Mountain Gotland American Jacob Romanov Double-coated or primitive Navajo-Churro Icelandic Racka Shetland Soay
Medium (dual purpose)		Hair
Columbia Corriedale East Friesian Finnsheep Panama Polypay Targhee		American Blackbelly Barbados Blackbelly Dorper Katahdin Painted Desert Royal White St. Augustine St. Croix Wiltipoll Wiltshire Horn

Selecting a breed of sheep

Selecting a breed of sheep <== SHEEP 201 INDEX

Selecting a breed of sheep

<== SHEEP 201 INDEX