Sheep

Sheep are among the most important animals that people have tamed because they provide both food and clothing. Long before people began to write history, shepherds watched flocks of sheep in the fields to guard them against attack by wild animals. Today, sheep are raised in all parts of the world. China ranks as the world’s leading sheep-producing country. Other important sheep-raising countries include Australia, Chad, India, Iran, Nigeria, and Sudan.

Sheep yield wool, meat, milk, and leather. They also furnish the raw materials for such by-products as glue, soap, fertilizer, cosmetics, and the catgut used in stringing tennis rackets. Moreover, sheep eat plants in areas that people cannot safely farm. Thus sheep enable people to raise food, wool, and other products on land that would otherwise be useless for human agriculture.

The body of the sheep

Domestic sheep vary greatly in size. The ewes (females) of some breeds may weigh less than 100 pounds (45 kilograms), while the ewes of other breeds may weigh more than 225 pounds (100 kilograms). The rams (males) are larger. Their weight, including a heavy coat of wool, ranges from 150 to 350 pounds (70 to 160 kilograms). Lambs weigh 3 to 13 pounds (1.4 to 6 kilograms) at birth.

Sheep are different from goats in many ways. They do not have the beard of the billy goat and do not have the goat’s odor. Sheep have a gland between their toes that is not found in goats. The horns of a ram usually curve outward. In some breeds, both rams and ewes have horns. In other kinds, only the rams have horns, or the breed is hornless.

Sheep walk upon hoofs that are divided into two toes. The ankles of sheep are slim. However, the upper part of their legs is muscular, helping them to move quickly and easily.

Sheep have no incisor, or cutting, teeth on their upper jaws, though they have eight on their lower jaws. They have six grinding teeth on the back part of each jaw. Sheep can bite off grass much closer to the ground than cattle can. In fact, where too many sheep are allowed to graze, plant life may become severely damaged. Most domestic sheep have tails, but these are cut off for reasons of cleanliness.

Sheep live for an average of 7 years, but some live as long as 13. Most ewes give birth to one or two lambs at a time. The mother’s pregnancy lasts for about five months. Ewes can begin breeding as early as six months of age, but most producers do not allow them to do so until they are about 1¹/₂ years old.

Wild sheep

Sheep may have come originally from the plateaus and mountains of central Asia. The largest wild sheep, the argali, lives in the Altai Mountains of Siberia and Mongolia. The male argali stands 4 feet (1.2 meters) high at the shoulders. His spiral horns are 20 inches (50 centimeters) around.

The great Marco Polo sheep of Asia lives in the Pamir mountains, the “roof of the world,” 3 miles (5 kilometers) above sea level. The Italian explorer Marco Polo first described this sheep in the 1200’s. The Marco Polo sheep is a little smaller than the argali, but it is remarkable for the wide spread of its horns. The blue sheep, or bharal, which is closely related to the goat, lives in Tibet. About half a dozen other kinds of wild sheep live in Asia.

Wild sheep look somewhat like wild goats. The sheep are high-spirited, daring, and self-reliant. They brave the fiercest storms of winter and climb higher than any other animals but mountain goats. Both wild and domestic sheep can consume plant foods that many other animals cannot consume. Wild sheep live in bands among the mountains and plateaus of the Northern Hemisphere.

All the domestic breeds of sheep are descended from two different kinds of wild sheep. These are the urial from southern Asia, and the mouflon, the only kind of wild sheep still living in southern Europe. Both kinds of wild sheep probably resemble their original ancestors. Many kinds of bighorn sheep live in North America.

Breeds of domestic sheep

Domestic sheep have been slowly and carefully changed from their wild ancestors. Originally, wild sheep were tamed for the sake of their hides and milk. They were also used to carry burdens. However, sheep soon became more important to people for their fleece. The coarse hair that covered wild sheep was replaced by a soft coat of wool through breeding. Only since the 1700’s have breeders developed the animals primarily for their meat. People often divide sheep meat into two basic types: mutton, the meat produced by adult sheep, and lamb, the meat produced by lambs.

Today, there are more than 800 breeds and varieties of domestic sheep throughout the world. There are five main groups of sheep, depending on their fleece. They are fine wool, long wool, crossbred wool, medium wool, and coarse wool.

Fine-wooled sheep.

Most fine-wooled sheep originated from the Spanish Merino breed. Spanish Merino sheep were developed in Spain. Their ancestors were probably brought to Spain by the ancient Romans. After the A.D. 700’s, Spanish Merino sheep became greatly prized. Until the late 1700’s, the Spanish government forbade taking them out of the country, but many were smuggled into Germany and France. It was in these countries that people developed the Merino into the modern type of sheep.

There are more sheep with Merino blood than any other breed. American Merino sheep have white faces and legs, with thick coverings of fine wool down to their toes and noses. Rams usually have horns.

The Rambouillet is another important breed that is descended from the Spanish Merino. This hardy sheep first appeared in the 1800’s. It is named after a town in France, but it was largely developed in Germany and later in the United States. The Debouillet breed, formed by crossing the Merino and the Rambouillet, was developed in New Mexico about 1920. People bred the Debouillet to produce wool and mutton under difficult range conditions.

Long-wooled sheep.

Four of the most important long-wooled breeds come from England. They are the Lincoln, Leicester, Cotswold, and Romney. Lincoln sheep rank among the largest domestic sheep and produce the longest fleece. The Leicester sheep is especially valuable to stock breeders for crossing with other sheep. It is the ancestor of most of the other long-wooled breeds. Ranchers have also used the Cotswold for crossbreeding. They often cross Cotswold rams with Merino ewes. Romney sheep originated in southeastern England and are popular in New Zealand, the northwestern United States, and other damp areas. Their bodies resist foot rot and parasite infections, common problems for other sheep in these conditions.

Crossbred-wooled sheep.

People have developed many modern types of sheep by crossing two or more of the accepted domestic breeds. Except for the Merino and Rambouillet types, probably all modern breeds developed from such crossing. The Corriedale is a crossbred sheep that has become popular throughout Australia, New Zealand, South America, and North America. In the Corriedale, breeders developed a kind of dual-purpose sheep that can produce large amounts of both wool and mutton. The Corriedale was developed from fine-wool and long-wool sheep in Australia and New Zealand. The breed was first imported into the United States in 1914. Similar crosses have helped create other breeds, such as the Colbred, Columbia, Montadale, Panama, Polwarth, Polypay, Romeldale, and Targhee.

Medium-wooled sheep.

These sheep are grown primarily for the meat they produce. They also provide a source of wool. The most important breeds are the Hampshire, Shropshire, Southdown, and Suffolk. Most farmers raise these sheep as purebreds. In western North America, people use them for breeding with white-faced range ewes of the Rambouillet, Columbia, Targhee, and other breeds. Such crosses produce black-faced market lambs sold for meat.

All four major breeds of medium-wooled sheep are popular on farms. These breeds originated in England. The face, ears, and legs of the Hampshire range in color from dark brown to black. The black face, ears, and legs of the Suffolk contrast sharply with its white wool body. The Southdown is a small sheep with a square-shaped body. The Dorset sheep produces lambs earlier in the year than do other breeds, thus providing lambs for the winter market. Other medium-wool breeds include the Cheviot, Clun Forest, Oxford, and Tunis.

Coarse-wooled sheep.

Karakul lambs have a glossy fur used to make fur coats. Lambs usually are killed and pelted when they are 3 to 10 days old, when the fur is most valuable. The Scottish Blackface, also called the Blackface Highland, produces a wool used in tweeds, carpets, and mattresses. Navajo sheep produce a coarse wool for rugs and blankets.

Other types.

Some sheep are not classified within the five main groups. For example, hair sheep have coarse hair rather than wool. Most hair sheep, such as the Djallonka breed, live in Africa.

Some sheep have been developed for milk production. East Friesian dairy sheep are raised in Germany. Milk from Roquefort sheep is used to make Roquefort cheese in France. Sheep’s milk differs in composition from cow’s milk. It contains more protein than cow’s milk and has a higher fat content.

People have also bred sheep to produce larger litters of lambs. Ewes of the Finnsheep breed, for example, average three lambs in a litter, and some have produced as many as eight living lambs at a time.

Raising sheep

People raise sheep in two different ways. The most important way occurs on the range, where sheep are herded in large bands containing from 1,000 to 2,000 or more sheep. The herds are moved about on large tracts of land that may be owned by the sheep owner, or may be leased from another owner or from the government. The sheep primarily eat range grasses.

The other important way of raising sheep occurs on farms. The farmer raises from 30 to a few hundred sheep, keeping them in fenced pastures. In winter, the sheep eat grain and hay grown on the farm.

It is usually more economical to raise sheep on large tracts of rangeland than on farms. On the range, where grasses and shrubs grow, the sheep owner does not have to provide feed for the sheep. Sheep can also live without water for long periods and can thus be raised on dry plains. In addition, sheep tend to herd together, and therefore they can be handled in large bands in open country with little labor. Throughout history, farmers usually have raised sheep far from cities and other thickly populated areas. Land costs in rural areas are lower, and the value of wool is usually high enough to offset the greater cost of shipping it over long distances.

Enemies of sheep

Sheep are attacked by various parasites and diseases. Foot rot and sore mouth are common diseases. Sheep suffer from internal parasites and also from a disease called sheep scab caused by mites and ticks. Meat-eating wild animals often attack sheep, and dogs sometimes kill sheep. Coyotes kill at least 4 percent of all lambs born in the United States each year. The kea parrot of New Zealand sinks its sharp, hooked bill into the sheep’s back, causing puncture wounds that can turn into open sores.