Question 1

Counting sheep

Accepted Answer

How many different kinds of sheep are there?

Sheep breeds

It is difficult to know how many breeds of sheep there are in the world, as only developed countries usually maintain breed registries. However, it is believed that there are more breeds of sheep than breeds of any other livestock species, with the exception of poultry. Worldwide, it is estimated that there are more than 1000 distinct sheep breeds. There are more than 60 breeds in the United States.

Sheep come in all different sizes, shapes, and colors, and there are many ways to classify sheep: according to their primary purpose (meat, milk, or wool), the type of coat they have or fibers they grow (fine, medium, long or carpet wool; or hair), the color of their faces (black, white, red, or speckled), and/or by specific physical or production characteristics.

Fine wool sheep

Fine wool sheep produce wool fibers with a very small fiber diameter, usually 20 microns or less. A micron is one-millionth of a meter. Fine wool sheep account for more than 50 percent of the world's sheep population. Found throughout Australia, South Africa, South America, and the western United States, most sheep of this type are Merino or trace their ancestry to the Merino.

The Rambouillet, related to the Merino, is one of the most common breeds of sheep in the US, especially the western states where the majority of sheep in the US can still be found. Fine wool sheep are best adapted to arid and semi-arid regions. Besides being known for their high quality fine wool, they are known for their longevity and strong flocking instinct.

Long wool sheep

Long wool sheep produce long-stapled wool with a large fiber diameter, usually greater than 30 microns. Long wool sheep are best adapted to cool, high rainfall areas with abundant forage. They are commonly raised in England, Scotland, New Zealand, and the Falkland Islands. In the US, the fleeces from the long wool breeds are popular among niche marketers and hand spinners. Popular long wool breeds include Border Leicester, Coopworth, Cotswold, Leicester Longwool, Lincoln, and Romney.

Carpet wool sheep
The coarsest grade of wool (usually over 38 microns) is used in the manufacture of carpets; hence, the name. Carpet wool breeds are usually double-coated, with a coarse long outer coat for protection against the elements and a short, finer undercoat. They are generally adapted to extreme environments. Carpet wool breeds found in the US include Icelandic, Karakul, Navajo Churro, and Scottish Blackface.

Medium wool meat sheep

Meat or "mutton-type" sheep produce wool, mostly medium (or long), but are raised more for their meat qualities. Medium wool sheep account for about 15 percent of the world's sheep population. The most popular meat breeds in the US are Cheviot, Dorset, Hampshire, Shropshire, Southdown, and Suffolk.

Hair (meat) sheep

Some breeds lack wool and are covered with hair instead, like their wild ancestors. Some hair sheep have "pure" hair coats, whereas others have coats that contain a mixture of hair and wool fibers that shed naturally. Hair sheep are found mostly in Africa and the Caribbean, but are also raised in temperate climates, such as the US and Canada.

Hair sheep account for about 10 percent of the world's sheep population and are the fastest growing segment of the American sheep industry. In fact, hair and hair x wool crosses now comprise 27 percent of the US sheep population. Katahdin and Dorper are the most popular breeds of registered hair sheep. Interest in hair sheep is also developing in other countries, including Australia, New Zealand, and Mexico.

Fat-tailed sheep

Fat tailed or fat-rump sheep are so-named because they can store large amounts of fat in their tail and rump. Fat-tailed sheep are found mostly in the extreme environments in Africa, the Middle East, and Asia. They grow wool, but are raised primarily for their meat or milk. Fat-tailed sheep comprise 25 percent of the world's sheep population. The only fat-tailed sheep in the US is the Karakul. The fat-tail was bred out of the Tunis. The Awassi, a fat-tail sheep from the Middle East was recently introduced to the US via semen and embryos.

Short or rat-tailed breeds

Short or rat-tailed breeds originate primarily from Scandinavia and Northern Europe. Their tails are thin and free of wool and do not need docked. They tend to be prolific. Examples of these breeds include Finn Sheep, Romanov, East Friesian, Shetland, Icelandic, and Soay.

Prolific breeds

Some sheep breeds are known for their prolificacy or high birth rates. Some were found to be naturally prolific, whereas selection has resulted in the high prolificacy of others. The first prolific breed identified was the Finnish Landrace (Finn). The Romanov was the next breed identified as being highly fertile. The Booroola Merino differs from the Finn and Romanov, in that its prolificacy is due to a single gene. The prolificacy of the Chinese Hu breed is also believed to be the result of a single gene. In prolific breeds, litter size usually exceeds 2.5 lambs per birth.

Primitive breeds
Primitive breeds have developed with minimal human selection pressure. They typically possess considerable genetic variation between members, but share characteristics indicative of a breed. A primitive breed will typically retain survival characteristics that favor production (and survival) with minimal human inputs.

Consistency among the products produced by the breed is somewhat lacking, but they are an important source of genetic variation that may not exist anywhere else. Many primitive breeds live in isolated mountain regions or on islands. Like some species of wildlife, many are endangered. Fortunately conservation efforts are underway to preserve these important genetic resources. Some producers niche market the meat from primitive breeds.

Question 2

Baa, baa black sheep

Accepted Answer

Why are some sheep black (and other colors)?

White wool

Most modern domesticated sheep grow white wool. This is because white wool is more desirable in the commercial market place because it can be dyed any color. However, sheep with white wool may have different colored faces and legs.

Natural-colored wool

Hand spinners, weavers, and other wool crafters often prefer "natural colored" fiber(s). Wool is naturally produced in many beautiful colors: black, gray, silver, brown, red, and moorit. Some sheep have spotted fleeces.

The Icelandic breed has the widest color range of any breed. The Shetland breed also produces wool of many different colors. Some fleeces have multiple colors. Sometimes, the inner and outer coats are different colors.

Fleece inheritance

It is not uncommon for black or colored lambs to be born in a white flock to white parents. However, in order for this to happen, both of the lamb's parents must be carrying a gene for color.

The inheritance of fleece or coat color can be quite complicated. Different genes control what color the fleece will be, what pattern it will be, and whether the fleece will be solid or spotted. Color genetics are also differ for different breeds.

Color change

The lambs of some breeds are born black or red and their fleeces lighten as they get older. When Tunis or California Red lambs are born, they are red or tan in color. As they grow, their fleeces gradually whiten, though they retain the red or tan color on their legs and face. Most Suffolk lambs are born black, but will eventually grow white wool. Romanov lambs are born black, but lighten to a soft silver grey as they make their fleece, a mixture of hair and wool.

Spotted sheep

One of the most uniquely-colored breeds is the Jacob. The Jacob's fleece is described as white with black spots. The white wool grows out of white skin. The black wool grows out of black skin. The Jacob's spotted fleece is mentioned in the Bible. Prior to the 20th century, Jacob sheep were referred to as "Piebald" sheep.

Coats of many colors

Hair sheep breeds also produce lambs with many different colors and color patterns. The genetics of hair color is also quite complicated.

Get your markers in

In the Old West, a few black sheep wandered the range. These colored animals were used as markers, one for every hundred sheep. The old timers counted the sheep and said, "Once your markers are in, your flock is in."

Question 3

Naked sheep

Accepted Answer

What are hair sheep?

The wild ancestors of today's domestic sheep breeds had long, coarse hair and a short, downy undercoat, which under domestication gradually became wool, while the long hair disappeared. Wild sheep, such as the Mouflon, still do not have wooly coats.

No wool

Some breeds of sheep remain true to their ancestors and do not have long, wooly coats that require shearing. This is because wool is a disadvantage in many environments and not profitable to produce in many circumstances.

Found in the tropics

It is estimated that approximately 10 percent of the world's sheep population is hair sheep, of which an estimated 90 percent are found in Africa and 10 percent in Latin America and the Caribbean.

Gaining in popularity

Hair sheep are increasing rapidly in popularity in the US and other temperate climates because wool is not as profitable as it once was and meat (lamb) is the primary source of income in the majority of sheep operations. Hair sheep are also valued for their production efficiency and "easy-care" nature. Hair sheep and hair x wool crosses now comprise 27 percent of the US sheep population.

Hair vs. wool

Hair sheep are not a cross between sheep and goats. They have the same number of chromosomes as wooled sheep. The primary difference between hair sheep and wooled sheep is the ratio of hair to wool fibers. All sheep have both types of fibers. Hair sheep have more hair fibers and wool sheep have more wool fibers. Wooled sheep need sheared. Hair sheep do not. Hair sheep also do not usually need their tails docked. Most wooled sheep have their tails docked for reasons of health and sanitation.

Differences

Like wooled breeds, there is considerable difference among hair sheep breeds, depending upon their origins. Some breeds and individuals have short, slick hair coats, absent of wool, while others grow thicker coats that contain a mixture of hair and wool fibers that shed naturally each year. Hair sheep tend to grow more wool fibers in cold climates, thus making them adaptable to different climate extremes.

Shedding sheep

Some of the newer breeds of hair sheep are composites or crosses between "pure" hair sheep breeds and meat-type wooled breeds. They grow more wool than traditional hair sheep, but shed their coats annually and do not require shearing. They may be more accurately identified as "shedding" sheep.

Other qualities

Besides shedding their "fleeces," hair sheep have many other outstanding qualities. Those with tropical origins have a high level of reproduction, are more resistant to internal parasites (worms) than conventional wooled sheep, and have a greater tolerance for heat and humidity. The breeds that originate from the more arid climates tend to excel in carcass traits.

Better leather

From the standpoint of leather, the closer a sheepskin approaches hair sheep, the tighter and firmer the fiber network, and, therefore, the better the skin for producing leather. This is the case because the numerous fine wool fibers, as opposed to the lesser number of coarse fibers of the hair sheep, cause the skin to be more open and loose in texture.

Lambs

Hair sheep lambs have excellent vigor. Their longer birth coats may enhance neonatal survival. Their growth rates vary according to their breed, genetics, and plane of nutrition. Many of the hair breeds fatten more like goats, depositing fat around their internal organs before laying on external fat. As a result, they should probably not be full-fed in a feed lot. As with goats, it is probably better to grow these breeds more slowly on a lower energy, higher-roughage diet.

Kinds of sheep

Counting sheep

Baa, baa black sheep

Naked sheep