Disease in Pigs

Pigs are subject to a number of diseases, and some of them can afflict humans as well. (See also Disease, Human.)

Anthrax is an acute, infectious, often fatal disease affecting all warm-blooded animals. In pigs the symptoms include swelling of the throat, weakness, and high temperature. Anthrax can be largely prevented by immunization.

Brucellosis causes infectious abortion in pigs. Its symptoms are not always evident; blood tests are the only reliable method of diagnosis. No known preventive medicinal agents or cures exist for this disease.

Hog cholera is a highly contagious virus that affects only pigs and is the most serious disease of domestic pigs in North America. The disease is marked by sudden onset, fever, loss of appetite, and weakness, though some pigs may die without showing symptoms. This disease has been largely controlled in most of the United States.

Foot-and-mouth disease , or aftosa, is a disease that affects cloven-hoofed animals. It is characterized by blisters and sores in the mouth and on the skin around the hooves. The disease is widespread in Europe, Asia, Africa, and South America.

Swine flu is an acute respiratory disease caused by the combined infection of a bacterium and a virus and can also affect humans. There is no known treatment.

African swine fever is a highly contagious, usually fatal, viral disease of pigs. Its symptoms and lesions resemble those of hog cholera. There is no known vaccine or treatment.

Leptospirosis is caused by a bacterium that is readily transmitted from one species to another and can affect both livestock and humans. Use of vaccines is an effective preventive measure.

Parasites affect pigs probably more often than any other species of livestock, with the possible exception of sheep. Internal parasites of pigs include large intestinal roundworms, coccidia, nodular worms, stomach worms, trichinae, thread worms, and whipworms. External parasites include hog lice, blowflies, mites, ringworms, and screwworms.

History

Wild pigs existed as far back as 36 million years ago. The hunting of wild pigs by early humans was often depicted in Western European cave and rock paintings dating back thousands of years.

Domestic pigs probably descended from one species—the Eurasian wild boar (Sus scrofa). Domestication of the pig coincided with the formation of the first permanent human settlements. The oldest known sites of pig domestication were established about 8,500 to 9,000 years ago in Iraq, Jordan, and Turkestan. The first domestic pigs in China existed about 6,900 years ago and in Great Britain as early as 2,800 years ago. The Vikings and, later, Spanish and English colonists brought swine to the Americas. Today wild or domestic pigs can be found on every continent except Antarctica.